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6/27/2015

Truss Dob Options for 12 inch mirrors and Larger



     In my last entry on the blog, I talked a lot about solid tube dobs, and spent a lot of time comparing a solid tube Orion XT10 to a Apertura 10" dob (which is out of stock).  I think I showed successfully that either dob is actually going to cost very similar, the only difference being do you want all the bells and whistles now, or do you want a base dob and add the modifications yourself over time?  I also touched on ATMing or making your own dob, though I didn't get into that too much, but can point you to the Wilhelm Bell site LINK if your wanting to look at some books to lead you into building your own. I also mentioned Rob Teeter's TT STS telescopes and though costing a premium dollar, they are premium telescopes that could last a life time if one wanted them to.

     Having said that, I touched on something that I believe comes to anyone in the hobby, and that is aperture fever. What is aperture fever? It is wanting to get a bigger and bigger scope to see more details in objects you observe, or to go fainter and see more objects.  The danger is that nothing ever is big enough.  The problem with it, is eventually, each observer has a limit to what they are willing to go in terms of costs, transportation, location, set up and take down time, and what they enjoy doing with the hobby. I own as I said last time a 4 inch refractor, a 10 inch dob, a 14 inch dob, a 17.5 inch dob, a 24 inch dob.  Everything is portable to me but the 24 inch. The 24 inch sits in an observatory built for it on property north of where I live. I had this noble idea that getting a 24 inch would mean going there more. It hasn't and then on top of it, when I do get there, I find that often I am tired from the 2 1/2 hour drive and when I use it, 24 inches is in truth too large for me.  My solution after owning it for 6 months, is to sell it off now and stay with the 17.5 inch. For me, my limit is a 18 inch scope or since I own a 17.5 inch scope, that is my limit.  I also found that being mobile and being able to go to various locations to observe is also important to me as I find it brings different people out to observe.  My point with this paragraph is aperture is not everything. One has to find their limit, find out where that is, and what it is they like to do BEFORE they make a decision on a scope. So get out, use scopes of different sizes, help set them up and tear them down.  Lift them, and decide what you like.  That has to be the first step when deciding to move up.

     So once you figure that out, then you have to begin to make some personal decisions.  I want to state something up front here, and that is if you ask someone about their scope, they are going to list what is great about, share a few things that need to improve, but leave you with the impression they have the best slice of pie in the area. I do it, and most people who observe that I have met do that. Why? To be honest, ego. We each want to think that the decisions we have made are correct, that we are right and that confirms the choices we have made. In the end, it really doesn't matter. I share that though because like buying a car, I would tell you I would NEVER own car x, or car y but I do own car a and my experience with car a is that they last forever, have low maintenance and are so much better than car x and car y. Yet a good friend may think I am crazy and swear by car x.  Telescopes are like that also.  Realize the bias involved, and ask some very serious questions of different owners and of the telescope makers themselves.  One advice I will give. I don't care what the instrument is used to observe, the key to this hobby is two fold.  First, if you don't use whatever you have, your not going to improve as an observer. You can have an average telescope with average optics, but if you use it a LOT, and learn how to observe, you'll see more than someone with a very premium scope who rarely observes.  Second, in the end, does it really matter? YOU have decide what you are going to use your telescope for and then do what makes you happy with it.  I have never met anyone in my area interested in what I do, observe and sketch what they see. That is what I LIKE to do.  Others like outreach in light polluted skies (I use to think they had lost their minds) or to take someone out and show them the brighter DSO's in the sky.  Others love splitting doubles, or viewing planets or comets.  There is no one thing that is right but if you know what you may want to do, that helps in deciding what dob to purchase.
     So who are the makers of telescopes in the 12 inch to 20 inch range?  I am not going to go over 20 inches as I don't think too many people go for anything larger than a 20 inch dob.  There are several key players in the dob business and I will be reviewing some of the most popular here.  I also will be examining the truss dob market here, not the solid tube market.

COMMERCIAL DOBS 

      To begin, in commercial dobs, there are several options in the truss like dobs that can be considered. Orion's XX12i model is a solid competitor. Orion's mirrors are a crap shoot, some are very good, many are average to slightly below average and some are below average.  Most observers who go this route will never notice an average to slightly below average mirror in my opinion.  Orion sells their XX12i model for around $1900.00 not including shipping LINK.  For that price you get the base, the intelliscope locating hand held computer, the bottom OTA, the truss tubes, the upper OTA, 3 bags for storing and transporting them and a shroud to block out light scattering.  It isn't a bad deal but I do feel there are better options.

     The next commercial dob that I have seen and looked through is SkyWatcher.  The 12 inch SkyWatcher Collapsible Dob sells for $999.00 LINK.  The tubes here slide down when not in use, or collapses to help store the telescope. Neither this scope or the Orion XX12i break down the base.  Mirror quality is about the same as the Orion and the major drawback to these two scopes and the next ones is weight. These are heavy to move around and if you have a bad back, you need to be careful to some extent. Then again, you can break them into pieces and move around but that will take a little more time than a solid tube dob.  The SkyWatcher and Orion XX12i and the next set of scopes, the LightBridge do not come with quality eyepieces and I still recommend the Explore Scientific 6.7mm, 11mm 82 degree and the 24mm 68 degree eyepieces (if you can afford it, the 24mm 82 degree eyepiece is also wonderful, but heavy and is a 2 inch eyepiece which all these scopes will handle. The 24mm 68 degree eyepiece is a 1 1/4 inch eyepiece as are the 6.7mm and 11mm 82 degree so you don't have to remove the 1 1/4 inch adapter in the focuser to view).  You also still need the collimation recommendations from my previous post for any of these telescopes.  This scope does not come with a shroud to cover the tubes, but they can be purchased in addition to the cost of the scope for about $89.00 LINK.  You do have to watch out for this shroud drooping into the light path though, so be careful.  Hmmm . . . . are you starting to see that there are more costs to owning a telescope than just the telescope?

     The next commercial end dob that I would really consider is the Meade Lightbride 12inch dob.  It is a commercial truss dob, rather heavy but usually comes with a decent set of mirrors and is a little easier to transport. The base for the 12 inch (and for the 16 inch which many people get as their first big dob) is heavy and made of particle board. It is NOT (and this is true for all of the commercial dobs) something you want to leave outside or store outside.  Particle board and moisture are not good companions.  If you want a lighter and better built base, there are people who build bases just for the Meade's to replace the ones that come with it and Dennis Steele at Dobstuff does this quite well. You can go to Dennis' webpage at Dobstuff to get his prices and see pictures of his base LINK under number four (4) on the left side of the page. Cost is $395.00 plus shipping. IF I had ever gone the Lightbride route, I would have purchased a new base just to reduce weight and to have a better overall quality product.  You can purchase a shroud for the 12 inch Lightbridge for $99.00 plus shipping at High Point Scientific LINK.  Again, you need the collimation tools and the eyepiece upgrades (of some sort).  So there are additonal costs but many, many observers are very happy with their Lightbridges.  The Meade Lightbridge also comes in a 16 inch model and that is VERY heavy. It is in pieces but the base is far more heavy than the 12 inch base, wider and takes up room to be transported if you take it in a car to a dark site.  It is a very reasonable price 16 inch telescope for $1999.00, yet you still need to collimate it so you'll need collimation tools (and at 16 inches, and at 12 inches I either recommend the Howie Glatter 2" tuBlug for $115.00 LINK with his 2 inch laser collimator LINK and you can decide on the $150.00 Standard laser (use in twilight) or the $175.00 635n High Power to use in the daylight.  These are two instruments that will last for ANY telescope you may purchase and are the premium for collimation.  The other alternative that is equal in performance are the Catseye Collimiators that are for use during the day.  The sight tube and cheshire combination 2 inch are expensive, but they are top premium for collimation tools.  LINK .  There are advantages to each, and a review of collimation tools is for another entry.  I do recommend one or the other (I own both and use both) if your going to use and have a 12 inch dob or bigger.

     After these commercial dobs, we now enter the realm of the semi premium to premium level dobs.  These dobs are going to cost more than a commercial dob because you are getting better quality components.  Mirrors are made by semi to professional mirror makers.  This means your mirror will be of a higher quality which means on those nights when sky conditions allow, you will have some outstanding views. Contrast is better on those mirrors as is the overall viewing experience I believe.  Motions on these telescopes are much improved, almost butter like, or in other words, very to extremely smooth.  Your able to customize what you want for your scope and the parts that go on your scope.  This is also where that bias that I spoke earlier comes into play.  There are advantages and trade offs for ALL of these scopes and you need to know that going in.  Owners will tout how awesome their telescope is, that is natural. They've paid a good amount for them, want their choice and money to have mattered, and in a way validated when others use it.  It's nice to have an ego inflated by others! On the other hand this is perhaps the KEY to this article and to all of them on telescope reviews. Get pass the bias, and if possible use a scope someone has purchased locally for a hour or so and see what you like, dislike, and what modifications they owner has made to the scope. Some of these will need modifications, they are built that way. Others come wonderful from their maker.  However, no telescope is not going to need some modification to make it your own.  The level of after support is also critical. So use the scope if possible, know what questions to ask based on what is important to you.

     Some questions to ask are (there are others that can be added) Who makes the mirror? What quality in the mirror are you looking for? What is the size of the secondary and why is that the right size for this telescope?  Is there a better option? What are the azimuth and altitude motions like? Will I need to modify the structure to improve those motions?  What is the upper OTA like? Is it a ring or a cage and which is better? Do I need a shroud and where would I get one?  How is the telescope collimated? Does the secondary have knobs?  What springs and knobs are used on the rear of the scope to move the primary during collimation? How are the vibrations when the scope moves? Does it hold collimation over an evening? What focuser is recommended and why? What options do I want, what options must I have, and based on those where I can cut some costs to increase costs on the build somewhere else?  What is my budget? Is it worth getting a well done scope and doing some of my own modifications over having something ready to go but costing more?  Do I need to install a dew system for the secondary mirror and for the eyepieces and Telrad or Rigel Quickfinder? Which red dot finder (Telrad or Rigel) am I going to use? Am I going to use a finderscope and if so, which one? Am I going to use the scope manually, buy a finding computer system with this scope or have it set up to add one latter?On   Do I have the eyepieces to fit with a telescope of this quality? What collimation tools am I going to buy? What is the weight of each component?  Is that weight too much, or just right for me (be honest).  How long is delivery, since you have to expect a relatively long wait time (up to 9 to 12 months in many cases).

STARSTRUCTURE TELESCOPES

     So here we go. We'll start with StarStructure Telescopes, on the premium makers on the market. You can find the website at this LINK.  StarStructure Telescopes are not made of wood, they are made of aluminium and are designed to be highly effective. The owner works and lives in Florida and makes a telescope that is extremely smooth in their motions, needs little modifications upon arrival, and is a pleasure to use. Astronomy Magazine had a nice review of the 12.5 inch StarStructure Telescope from 2009 at this LINK. The scope for being made of aluminium is light weight, and I have seen that for myself. Like the author in that article mentions though, that light weight can mean that in a wind, and the author states a wind of 20mph to 25mph, I would put that down to around 10mph to 15mph (gusts) that the telescope will move on its in a that breeze or gust.  The bottom mirror cell and bottom OTA is heavy, especially as you increase in mirror size and it can take two people to move a scope above 16 inches for the bottom OTA. That or have wheels installed and two ramps (think of ramps used to get a motorcycle or ATV up into the back of a car or truck) to get up into the back of your vehicle. My last observation or criticism is cosmetic (doesn't impact the structure or use of the telescope) is that the painting on the aluminum will be chipped easily and will flake off as you use the scope and move it. IF you use one in an observatory, that will minimize it but it still happens.
     Having said that, if you choose a StarStructure you are getting one of the best made telescopes in the market and you will not go wrong with one.  On pricing, Mike,  the owner is no longer making a 12 inch model. His smallest is 14 inches and he prepares them in 3 basic groups. Group 1 is with no optics installed, you are buying the structure only.  Group 2 is for manual use dob owners only.  Group 3 is for GoTo (computer hand controlled) telescopes.  Group 1 will cost based on aperture. A Dob made in the 14" to 20" is $270 per inch of aperture for a Group 1 Dob. So a 14" would be $3780, a 16" $4320 and a 18" would be $4860.  A Group 2 dob (using same sizes) is $310 per inch of aperture. So a 14" dob would be $4340; a 16" dob would be $4960; a 18" dob would be $5560; a 20" dob would be $6200.  Prices do not assume shipping I assume.  Finally if you want a computerized GOTO dob that finds objects in the sky and you follow the controller to get to the object, that is a Group 3 dob and the cost per inch of aperture is $480 per inch.  So a 14" dob is now $6720; a 16" dob is $7680, a 18" dob is $8640 and a 20" dob for fun would be $9600.  GOTO is nice, but costly! If your wanting a high end, premium dob for manual use, I would recommend either his 14", 16" model if weight is a concern for Group 2 or the 18" or 20" for the larger dob if weight isn't a concern and you want to go pretty big. Again if your interested in StarStructure here is the LINK to their website. You won't be disappointed when you get your telescope.

TEETER TELESCOPES

     If a wooden dob telescope is your thing, you won't find a better built telescope then Rob Teeter at Teeter Telescopes LINK.  These telescopes come in two styles, the TT Stark and the TT Classic.  The TT Stark is the "bare essential" telescope and is priced lower than the TT Classic that Teeter makes.  The Stark includes the following items:

Teeter's Telescopes Exclusive Clear-Gloss Wood Finish;
- Utilization of 5/8" and 1/2" Baltic Birch Plywood, professionally milled;
- Flotation-type Primary Mirror Cell (10", 9-pt; 12" & Larger, 18-pt) with sling;
- Astrosystems 4-vane Spider and Secondary Holder, tool-less collimation;
- Moonlite Single-Speed 2"/1.25" Crayford Focuser in Black Anodized Finish;
- Rigel QuickFinder or Telrad zero-power finders;
- Black Enamel and Tough Clear-Coat Finished Altitude Bearings;
- Virgin Teflon and Black pebbled FRP azimuth and altitude bearings;
- Rubberized feet on underside of ground board for a sturdy footprint;
- Moonlite Ball & Socket lower truss connectors;
- Aurora Precision locking upper truss connectors;
- Compatible with all of our most popular upgrades and accessories; etc.

     The TT Stark's come in a 10", 12" and 16" model. Prices depend on what mirror option you go with.  A mass produced GSO Primary mirror (like what is in most commercial dobs) means the 10" costs $2900, the 12" costs $3025 and the 16" costs $3925 (plus any extra's you want).  Go with a Lightholder mirror (excellent mirror choice btw) and those costs go up to $3825 for the 10", $4500 for the 12" and $5750 for the 16".  Want the best of the best or a Zambuto mirror, costs go up more but then you have the optics for life:  10" cost is $4250, 12" cost is $5025, 16" cost is $6450.  If you have your primary and secondary mirrors in this size then costs are much lower and can be seen in this LINK.

Size           GSO Mirror              Lightholder Mirror       Zambuto Mirror
10"               $2900                         $3825                          $4250
12"               $3025                         $4500                          $5025
16"               $3925                         $5750                          $6450

     If you want more of the bell and whistles and more of the fancier build from Teeter then the ir TT Classic line is for you.  The Classic line comes with the following which you can compare to the TT Stark line above. To see pictures of these features please go to this LINK on the Teeter WebSite.

-Truss Ring. Allows for the trusses and upper OTA to stay fixed together and then the the ring they are connected to on the bottom connects to the lower mirror box and bearings for easy and quick set up.
- Flotation Primary Mirror Cell Support that includes from the site "Our standard design allows the mirror cell to"tailgate" or "tip out" for easy installation and removal of the primary mirror. Our standard design also includes a Kevlar lower-edge sling support."
- Catseye Mirror Spot on the Primary mirror for collimation. This allows for use of the Catseye Collimation tools, considered by many to be the best method for collimating your mirrors.
- Astrosystems 4 vane spider
-Antares Optics Secondary Mirrors. An excellent secondary mirror.
- Moonlite 2"/1.25" Single Speed Crayford Focusers with 1.25" eyepiece adapters, and 2" and 1.25" brass compression rings.The dual Moonlite focuser is available as an upgrade and I personally recommend that.
- Rigel Systems Quickfinder. Some love the Rigel, I prefer the Telrad which you can get as an upgrade.
- Choice of Wood Stain, Natural, Cherry or Maple. Teeter is known for their Cherry finishes and they are beautiful!
- Internal Mirror Box Baffling. Rob Teeter explains it best (something I had to mod on my scopes) by stating on his site "Internal, velvet-lined, Mirrorbox baffling and structural component consisting of 1/2" Baltic Birch plywood "dado'ed" into place. This acts both to make your mirrorbox super rigid and act as a "knife edge" baffle to knock down stray light from entering the optical pathway."
- Dual Boundary Layer Fans:  From the site "Dual Boundary Layer 12-volt Cooling Fans which pull ambient air into the mirrorbox and vent through a pattern of ventilation holes on opposing side of mirrorbox, effectively "scrubbing" the boundary layer away."  This is an outstanding feature for a closed mirrorbox and helps to improve the time before your scope is ready to observe and while observing, ensuring that as heat continues tor radiate off your primary mirror, it doesn't impact your observation of whatever object your viewing.
- Kendrick Power Distribution System.  "Kendrick Astro Instruments DigiFire-7 Controller for organized splitting of 12-volt power to various accessories."
- Light Shroud to block out stray light
- Truss Pole Carry Case. Help to keep the truss poles in one place and ease of transportation.
- Engraved Brass Name Plate:
- Hardware Package Choice: Brass, Black or Nickel/Chrome hardware.
- Black Velvet Light Trap in Upper Tube Assembly. Keeps stray light from impacting your view in the upper OTA.
- Moonlite Ball & Socket Lower Truss Connectors.  Wonderful connectors on the truss components on the lower OTA as I use them on my own scopes and they are great and easy to use.
- Aurora Precision Upper Truss Connectors. From the site: "Aurora Precision's machined/anodized aluminum upper Truss Connectors are the latest and greatest product for making a rigid connection between the upper end of the truss structure and your upper tube assembly (UTA)."
- Moonlite Accessories  1.250" O.D. black-anodized Truss Poles on our 12.5"-20" scopes. Same poles I use and they work great.
- Virgin Teflon with Center Pad for Azimuth movement
- Black Fiberglass Reinforced Plastic (FRP), the new industry-standard now that Ebony Star laminate has been discontinued, is utilized on both azimuth and altitude axes.  When combined with virgin Teflon the motions are smooth and free.
- Custom Matched Wheelbarrow Handles

There are upgrades available at this LINK for additional costs. LINK.  One that I HIGHLY recommend is the filter slide.

Costs: Here are the costs for the TT Classic and the TT Classic comes in these sizes;
10" F/6, 12.5" F/5, 15" F/4.5, 18" F/4.5 and 20" F/4.5. Structure only assumes you provide the primary and secondary mirrors. Prices are for 2015 and are subject to change according to Teeter Telescopes.

Size                 Lightholder Optics                Zambuto Optics               Structure only

10" f/6                    $4475                                 $4900                            $3100

12.5 f/5                  $5250                                 $5775                            $3300

14.5" f/4.5              $6175                                 $6675                            $3475

15" f/4.5                 $6350                                $6925                             $3500

16" f/4.5                 $6700                                $7450                             $3600

18" f/4.0                 $8000                                $9675                             $3800

18" f/4.5                 $7625                                $8725                             $3800

20" f/4                    $9500                               $11450                            $4000

     The one thing I really like about Teeter Telescopes is Rob does an excellent job of trying to appeal to as many consumers as possible and providing them with a telescope that fits their needs. All of the scope makers do this.  So if you love the look of the Teeter and go with them, you have to decide what is your price point and what options you want or don't want and which model fits your budget. There is a good review of a Teeter Telescope on Astromart from 2010 at this LINK.  I don't think I like the notion of pulling the mirror out everytime I transport, because with my own 14" and 17.5" I only transport them to view. Not a major issue, but I have premium mirrors in my scopes and I don't want a chance of touching them.  The not going to the horizon is a mute issue for me. The only object that low for me is Omega Centauri and that is only in the spring.  Most scopes that arrive, especially dobs, need tweaking. As John B. said on that Astromart Review, the Teeter he had did not require much tweaking and that means the build was a good one. It should be if your buying a TT Classic, but from what I have read, Rob puts into the TT Stark line the same level of care and detail for what you are getting and paying for. There is another solid review located at this LINK from a white paper by Phyllis Lang.

NEW MOON TELESCOPES

     The next builder and company I will mention is one I came within a hair from buying from, but changed my mind at the last minute.  New Moon Telescopes.  New Moon is relatively new in the business, just a few years but they have an excellent reputation and make a tremendous product. Relatively speaking though if you look at their Web Site at this LINK and their prices, you'll find that their prices are about the same or slightly higher than other companies like Teeter Telescopes.  On their website you will have to go to their Telescope section, drop down to the scope you want to review and then scroll down, click on that scope and review the details and price.  For me personally, the shipping of a telescope from New York was one factor why I opted not to go with them. The second was I was unsure of some of their builds.  If I had read this review (PDF) at this LINK I may have opted to stay with my initial decision. They and Teeter would be the ones I would consider for any rebuild down the the road.  I haven't seen or used a New Moon Telescope where I have used the other scopes I have mentioned or reviewed so far.  I hope someday to remedy that.

OBSESSION TELESCOPES

     The next company I think I have to mention is Obsession. Obsession Telescopes have been around for quite a long time, have a stellar and solid reputation and are the scope/dob that most ATMers build/model their scope after.  Obessisions come in a Classic Model or the Ultra Compact or UC model.  I have seen one UC model, a 18" UC and I have to say that some of the reviews I had read about them were spot on. The bottom mirror cell was indeed heavy, it took two of us to lift it out of the back of a pickup.  The scope assembled quite easily but it did show some collimation shift that the owner was working on correcting. Thus the UC seems to be a very solid scope, once you work out the modifications for making sure some of its issues are resolved.  There are other models that you do the same with that don't quite cost as much though which I'll cover later.

     The Classic Obsession though is a rock of the Dob market.  They arrive in solid shape, usually needing some modifications to make sure they are balanced, that the components they ship with fit and work, and perhaps needing a little bit of an ATMer in the purchaser to maximize their potential. There are two older reviews that I will share on them, and if you go through them, you'll see what I mean about having to make minor adjustments.  They are both found on CloudyNights:  Link 1 is a PDF and Link 2.  Please know that Mr. Gage in Link 2 sold his 15" Obsession in 2013 after owning it for 4 years.

Here is what you get and the price.
12.5" f/5   Price: $3495 plus shipping and crating.
Included:
Primary Mirror
12.5" - 317 mm OMI 2 inch thick mirror (2 inches is THICK for a mirror in today's world. That will mean a lot of cooling of the mirror for good observing.
96% reflectivity
Enhanced Aluminum Coating and Dielectric Overcoat (a supreme coating)
Center marked for precise collimation
plus Interferometry certification
Secondary Mirror
2.14" - 54 mm United Lens 1/10 wave or better
Interferogram included
96% reflectivity at 550 nm
Mirror Cell
9 Points
Other
Wheelbarrow Handles
Focuser is a basic JMI EV3 single speed focuser. Probably want to upgrade at least to the dual speed JMI EV1 for $195.

Note Upgrades I would recommend with costs.
Telrad:  This scope does not come with the Telrad so you will need to get one.  You can buy them for $39 from places like ScopeStuff or for $45 from Obsession.
Dew Heater for Secondary: If you live where it is muggy or observe come fall or winter you'll need this for $75.
Shroud: Depends on size of scope. Two options, get the Obsession shroud for 12.5"=$179; 15"=$189; 18"=$199; 20"=$209
OR
Go to Shrouds by Heather (from TeeterTelecopes, Heather is Rob's wife) at this LINK and you can provide your dimensions and get a shroud for a lot less. Get the shroud in black unless you want to pay extra for the black liner.

12.5" to 15" for the Classic Obsession (NOT THE UC) $85.00
16" to 18" cost is $105
20" to 24" cost is $135

     Obsession charges $35.00 for a counter weight kit to attach to the back of the mirror box. You can pay that or go to Lowes or Home Depot, get 1 inch PVC pipe and end capes, glue one end cap on the end (need PVC glue) buy some lead shot or BB Pellets from Walmart or a sporting store, fill up the PVC Pipe, put the other end cap on, you can spray paint it black if you want and then use some zip ties to attach it yourself to the back end. Your choice but you will need to counter weight and with the Obsessions you may need up to 2" PVC pipe to counter balance the scope.

     Obsessions are premium scopes that need some tweaking by their new owner to make them totally ready for observing. I almost purchased a used one but didn't it.  You won't go wrong if you get one, you just to plan to put some lovin into the scope.

Price for the 15" f/4.5 Classic: $4995 plus shipping and crating.
Price for the 18" f/4.2 Classic $6995 plus shipping and crating
Price for the 20" f/5 Classic $7695
Price for the 20" f/4 Classic $9495

     Basic components are the same as the 12.5 and you will need some of the upgrades I mentioned .  Plan on a TeleVue Paracorr for all of these scopes (including Teeter and New Moon and the others).  That is another $475.00 and don't forget that none of these scopes come with eyepieces. You still will need at least the three beginning eyepieces I recommended.

WEBSTER TELESCOPES

     I have to state up front that a Webster Telescope is one of the best telescopes I have owned, used and reviewed here now.  The 24" is a tremendous scope with outstanding motions, is light with about 75% of the weight in the mirror box, and as the reviewer posts and I concur, moving that bottom OTA is a pain and not something at 20" or above you want to do by yourself.  Nor do you move it a long distance, at least not without the wheels attached to it.  The whole build of this telescope is a minimalist feel, something that I really enjoy (see my other scopes) while maximizing the design for efficiency of use. Again, motions are perhaps the best I have ever used and I enjoy both star hopping and observing manually with this scope as it is so easy to track objects. Sketching with it has been great also because of the motions. The large bearings help with this.  One thing about a Webster is that their truss poles (at least mine are) came marked, so I can easily fit them and align them in the same location, helping to minimize collimation and that helps to maximize observing time.  The rear mirror cell is very basic and open, allowing the large mirror to cool down. The mirror cell is 18 points on 3 bars, and the bear metal steel on the back can rust when exposed to moisture so the my mirror cell was coated in a clear coat to protect it from staining the mirror on the back side.  The secondary mirror holder works with it s four bolts and collimation is secure throughout with this scope. The upper OTA is painted black to help minimize light reflecting into the optical path as is the mirror box. The shroud is okay, fine at a dark location but not great in a suburbia or urban location.  Do I like the ServoCat and ARGO on it? Yep, the tracking works well and I do enjoy that for sketching.  Having said all that, for me a 24" scope, even a Webster is too big so out it goes. My plan is to replace the 24" with a 20" Webster with a Zambuto Primary as that scope is only at 76 inches for the eyepiece height which is slightly more than the 17.5" dob I have now, but not as much.  The bad part on Webster has always been their lag time between ordering and delivery.  They are great at answer questions and stuff, but don't expect this telescope right away. Give it 9 months to 15 months and your good to go. Order it, pay for it, and wait. Here are the prices for their dobs from their Website and prices can change over time so always check with them.


THE FOLLOWING IS A LIST OF OUR MOST POPULAR TELESCOPES.  OUR FACTORY HAS THE CAPACITY TO CRAFT ANY TELESCOPE FROM 14 TO 60 INCHES.

Please consider our newest D series scopes powered by Zambuto Optics:

14.5" f/4.5 for only $6,899  ($109 month*)

18" f/4 for only $10,300 ($147 month*)

20" f/4 for only $11,599 (172 month*)

The following C series telescopes feature Kennedy Optics:

22" f/3.3 for only $14,100 ($190 month*)

22" f/3.6 for only $12,599  ($177 month*)

24" f/3 for only $16,899  ($230 month*)

24" f/3.6 for only $14,899  ($211 month*)

28" f/3.3 for only $20,399 ($324 month*)

28" f/3.6 LUNAR $18,499  ($275 month*)

28" f/3.6 for only $18,899  ($282 month*)

28"  f/4  for  only  $18,199  ($280 month*)

30" f/3.3 for only $24,100  ($353 month*)

32" f/3.6 for only $27,199  ($428 month*)

OPTIONS:

ARGONAVIS:  $1000 - Installed including 10K HD Encoders, Hidden Wiring, 12v Power run to Switchbox, and all Hardware.  We have the cleanest Argo installation anywhere.

SERVOCAT GOTO:  Installed and Tested, Hidden Wiring, 12v Power run to Switchbox and all hardware.  Servocat is installed in protected location, no switches or wires exposed to step upon.  We have the cleanest Servocat installation anywhere.  Servocat requires Argonavis or Sky Commander for GOTO.

12-18" scopes - $2400 includes stalk for mounting controls

20-28" scopes - $2500 no stalk needed, controls on UTA

30-40" scopes - $2600 no stalk needed, controls on UTA

Wireless Hand Pad - $275

POWERED GROUND BOARD:  $200 -  (FREE for a limited time with purchase of the Argonavis + Servocat combo on your new Webster telescope!)  Allows scope to spin without tangling wires.  Allows remote placement of battery.  Included Switchbox controls fans, Argonavis and Servocat.  Supplies 12v system power to telescope.

SUPER FANS:  $150 - Four high power fans for quick cool down.  Installed and Wired to Switchbox allowing all on, one on, or three on.  Powerful but quiet operation.

All of our telescopes come standard with Telrad finder, Dual Speed Feathertouch focuser, Transport Wheels, and Light Shroud.  Necessities that we would not even think of charging you extra for.

 This is not a cheap option, but it is a very well built option and one I think most people would enjoy.  I will be owning a 20" Webster in the near future (2 years for ordering and lag time).

Webster C24



DOBSTUFF

     I have to admit, and you will pick it up in the Webster comments and here, that I like minimalist designs. Legendary telescope designer and innovator Albert Highe designed the first set of scopes that eventually came to be made by Dennis Steele at Dobstuff. Albert Highe has a PhD in Physical Chemistry from Cal Tech (1981) and loves to figure out how things work and to make them better. A couple of shots of Albert Highe with scopes he has built.




     As you can see in the first photo, Albert has his 12.5 3 strut scope in the background, and his 17.5 strut scope in the foreground with him.  You can read about these builds at this LINK.  In the bottom picture you can see how he continues to push the boundary for a minimalist approach design to making telescopes. Albert has shared his designs and thoughts on telescope making in two books from Wilhelm Bell which you can see at this LINK and purchase if you wish to. Fascinating mind, fascinating thoughts on telescope making and how to avoid collimation shifts and other problems some of these designs have thought to have.

Michelle Stone in California used her woodmaking skills to take Albert Highe's design and create Plettstone Telescopes, based on a 3 Strut Design.  You can see Michelle in this picture with one of her scopes (image is taken from the net):


     Michelle was very successful with her telescopes and sold a lot of them, before exiting out of the business and not making telescopes to sell.  Her telescopes are frequently found on the used market and the quality of the scope is fantastic. She offered Zambuto mirrors with her telescopes so if you find one with one of those mirrors, that would be a catch! Michelle lives I believe in the Sierra Nevada Mountains of California and she and her husband have invited from time to time, several of the clubs from California to observe with them on their property.

     After Michelle exited or about the same time, Dennis Steele came out with his company DobStuff.  Dobstuff has been making 3 pole Strut telescopes and kits that you finish for sometime now.  Dennis has also veered into making truss dobs now by modifying his techniques to fit those telescopes. I have to state up front that I have a major bias to these scopes as my 14" is a 3 Strut from Dennis with a premium mirror, and my 17.5" is also a Truss Dob from Dennis and I enjoy both scopes.  So before I get into why I like them, here are the services Dennis offers.

First off, Dennis will make you a kit and then send to you for you finish and assembly the final Telescope. From his website he says:

"If you can drill your own holes, use sand paper and varnish some wood, you can save a bundle building a telescope.. The kit includes EVERYTHING.
All the wood pieces and hardware (nuts, bolts knobs and focuser bracket).
All Teflon bearings and Ebony Star.
All aluminum tubes for struts and the mirror box (includes tube inserts).
All wood is furniture grade Baltic birch 13-layer plywood.
Delivery times for kits are typically 30 days (usually less).
Truss kits 8-tube single upper-ring configuration. Full UTA available.
Fine sand, stain and/or varnish as you prefer, then assemble the telescope -- Finally, complete the scope by mounting your own mirror cell and primary, mount the focuser and install the secondary and aluminum tubing."

Need a mirror cell? Dennis will build you and customize one for you if you call, and he'll let you know his pricing up front. Now as with ALL prices on this entry, they are subject to change and DO NOT tell one of the makers I said they would sell you a scope at the price on my blog. YOU MUST contact them to find out their current pricing, since you may want something extra.
Complete Kits‡:
                  Strut          Truss**
 6" - 10" ............... $595 $CALL
12"-14"................. $795 $1395
 15" - 18".............. $995 $1495

You can see all of this from Dennis' DobStuff site at this LINK.

Have a mass produced dob like an Orion, a Zhumall etc. that you want made over into a truss or a strut dob? Dennis will do that using existing parts. You do need to call him though as you need to decide what he will use, what will be new and the total cost. Dennis keeps that very private between you and him as do all the scope builders.  Here are the prices on the rebuild minus any extras you may want:

                                 Strut Truss**
  6" - 8".................. $895 $CALL
  10" ....................... $995 $CALL
  12" - 14" ............. $1095 $1595
  15" - 18"............. $1495 $1995

Want a new telescope? EDIT: Dennis contacted and let me know the following which I am editing here:

"When someone purchases a complete telescope from me DO NOT need to supply the optics. I provide everything they need -- optics, mirror cell, spider, secondary and focuser."

 Complete Telescopes‡
                   Strut Truss
  10"................ EMAIL EMAIL
  12"................ EMAIL EMAIL
  16"................ $3995 $4495

These telescopes include:

1/16-wave 16" or equivalent.
Matching secondary mirror.
Destiny "observatory-trade" curved-vane spider.
Moonlite 2" crayford focuser with 1.25" adapter.
Custom mirror cover included.
Custom clamp for your finder
1.25# counterweight on clamp.
Focuser Baffle.
Truss telescopes 8-tube, single upper ring. Full UTA, add $150
Click here for some weights and measures.
Delivery times for telescopes are typically 60-90 days (usually less).
Plus shipping on ALL scopes listed above.

So Dennis will rebuild from your existing dob, build you a kit at a cheaper price if you can sand, stain and assemble or build you a new scope. The key to getting started is to call Dennis and/or email him.  My experience is that Dennis has always been forthright, open, and communicates regularly through the build process.  Dennis builds a remarkable scope that works extremely well. I am rough on my scopes. I use them from three to five times a month, weather cooperating. I use them all four seasons of the year and thus they see a lot of use. My 14" strut design with Zambuto optics performs outstanding today. Okay I will admit I made modifications on the build I got from Dennis by adding some counterweights, moving where the bearings connect to the struts thus decreasing the over height without impact the view.  I improved the motions by decreasing the amount of Teflon on the bearings thus reducing friction and using Sailkote to make azimuth motions improved.  On my 17.5 I added counterweight, adjusted the Teflon again, and am moving where the finder connects to the upper ring. I numbered on both scopes my struts and truss poles to improve collimation and I faithfully use my string variant to ensure no collimation shifting during observing on the 14".  I also have darked the lower OTA's now to help improve contrast. To be upfront though, I tend to mod any new scope that I get over the first 10 or so observing trips to make it my own. You should do the same with yours!

Now one thing I have had a few people question, especially on my 14"  strut is what about collimation shifts. They expect I have them but using the Howie Glatter barlow collimation set I have with the 2" 635n Laser collimator and tuBlug, I do not suffer in my 14" from any collimation shift.  My 17.5 also has no collimation shift.  The design is open, very open and both mirror are thinner, and cool rapidly.  I have a shroud for the 17.5 but at my dark sites I do not use it as I don't get hardly any stray light in the optical path and I find by keeping the mirrors open, the radiate their heat away. Critical is a black shield across from the focuser and I did notice an improvement by darkening the inside of the mirror box. I also use a black round shield that Dennis made for me around the mirror to protect it and that helps to improve contrast as well.

     What do you get from Dennis/Dobstuff for the price you pay? You get an excellent scope that in some ways like the Obsession (but in truth like any new dob), needs a few TLC' mods to improve it and make it an outstanding scope. Understand, an outstanding scope to me, is one that performs the way I want it to, not how someone else feels it should be. I am the observer, so the scope has to work for me, my way, and that usually means some modifications.  I mentioned the main modifications I have done that improved motions for altitude and azimuth, improved collimation and contrast on the scopes.  These are highly functional, and excellent scopes and if you know how and what to do to them, they work extremely well, as good as the ones listed above. I haven't sold mine nor will I. Dennis is in California, and the shipping for me in Utah is reduced from back east and I like that. I also observe in a dry climate and though I have used my dew heater on my secondary in the fall and winter, more often than not I don't need it. His design based on Albert Highe's design, is a highly  serviceable scope that with a few mods, works as well as an Obsession (and yes, I have owned one of those) and the others above.  The biggest personal praise I can say about Dennis' products are that they are for me, my choice for a personal scope and each one works at a high level I demand and expect of my equipment.  I do a ton of observing, more  then most, and a Dobstuff Strut or Truss, will work outstandingly well with a few tweeks for the personal touch one likes.  I currently own a 17.5 Truss Dobstuff, a 14" Strut Dobstuff, a XT10 (all 3 with premium optics) a AR102 by Explore Scientific (refractor) a L35 Lunt Solar Scope and I am content.

    So those are the major telescope manufactors here in the U.S. that I know of.  They are the ones I have purchased used or new, and the ones that I would purchase new from.  You cannot go wrong from either of them. Again though, it comes down to the questions you ask, what is important to you, what trade offs in their designs your willing to accept, what price point you'll accept and finally, what YOU want.  None of these builders are going to give you junk.  Amateur Astronomy is a hobby, and as such, it does require equipment to go observing with. The main part of that is a telescope. A dob is a wonderful choice and if you choose a commercial dob or a premium built dob, or choose to follow Albert Highe's model and make your own and design your own, you won't go wrong. Just make an informed decision for yourself by talking to multiple of these people, asking them the questions that matter to you, and then going with who your comfortable with and whose price your comfortable with.

     I said it above and I will end here. I would be honored to use a telescope from ANY of these makers in the field. Now if I only had another 150 years to observe so I could try them out over time! Good luck and I am sorry if I don't point out what you should do. I own two Dobstuffs, I have owned an Obsession and another scope from a manufacturer above and I would love to own a Teeter, a New Moon, a StarStructure, a Webster again.  Nothing would please me more. Unfortunately I don't have an extra $50,000 to $100,000 to spend on equipment right now and stay married (27 years this past week!).  I love astronomy, I just love my wife and family a little more so I can't purchase one of each and review them.  Again, the key is knowing what questions to ask, and then ask them to at least two if not three or four of these builders that fit in your price range.  I hope this has helped in some way, and good luck if your in the market to buy a telescope and though I stated above our ego's make us bias to our equipment, if we can admit that and remember this is but a hobby, we can enjoy what we do have, regardless of what others have around us and do what is the heart of this hobby, view, observe and most of all enjoy all those wondrous objects up in the night sky. Equipment in the end is but a tool to do that so don't get caught up in the equipment but do stay caught up in observing the objects up in that majestic night sky we call our universe.

9 comments:

  1. Hi -
    Thanks for the great article. A question: how does the stiffness of you 17.5" truss and 14" strut + string 'scopes compare? I'm trying to decide between struts + strings vs. truss for a 16" from Dobstuff. Thanks in advance!

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  2. Hi -
    Thanks for the great article. A question: how does the stiffness of you 17.5" truss and 14" strut + string 'scopes compare? I'm trying to decide between struts + strings vs. truss for a 16" from Dobstuff. Thanks in advance!

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  3. Hi Mike,

    I have no flex that impacts collimation in either my 14" or my 17.5" dobs. That comes from checking at the beginning of a session and then about 4 hours later using a Howie Glatter Laser collimation. Anyway, with the string variant on the strut I show no collimation shift. I would not do a non-string variant with the strut through, as I would expect flex and thus an impact to the collimation, perhaps a shift during observing. My 8 pole truss performs outstandingly with no flex. At f 4.5 it is a little big and I would prefer a 3.5 to 4.0 in the focal ratio. In terms of breakdown my 14" strut breaks down a little quicker than the 17.5". If you look at pics of the 17.5 though I have put pipe foam around the tubes to ensure that the cold doesn't impact me too much in fall, winter and spring. You won't lose either way. I use my 17.5 the most now.

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  4. Anonymous7/12/2016

    Jay:

    Now that you have had your Dobstuff scopes for a couple of years are there any modifications you would have had Dennis build in?

    Grant

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  5. This comment has been removed by the author.

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  6. Adjustments I would have Dennis make? That is probably presumptuous on my part because I am sure for 90% of his buyers, they are totally content with their scopes as they come. What I have done and would recommend is to increase motions, I reduced the size of the teflon pads on the alt bearings on the rocker, and the size of the circle bearings that contact the apple board on the bottom of the rocker for azmuith motions. That helped but if he leaves them the way they are, others can make them the size they are. My 14" had a way to transport the upper ring to the field sitting on top of the truss and it fits in my Outback. The 17.5 doesn't, though Dennis has made that adjustment with another client now. I would want to see a safer way to transport and store my upper ring on my 17.5" scope. I am not sure if this is possible but if the Astrosystems holder for secondary could be used, I think I would prefer that than the method used currently, glue. No problems with my secondaries, just something to perhaps consider. Dennis glued the primary of the my 17.5 down and I have released it and used a sling that is basically my design or modification. Having an option for that would be good. I didn't detect via a star test any negatives to gluing the primary down, just again, something I would probably inquire about. Other than that, I have just made some adjustments to the scopes that are my adjustments, not anything I would inquire to Dennis if he made another for me so I won't go into those here. I love my Dobstuffs. You can get the motions where you want them to be, they are lightweight compared to other premium scope makers and that weight is critical for me. I wanted a couple of scopes that would last into my 60's. I got them. They are portable, even the 17.5" I can lift for 5 to 10 feet with no issues on a bad low back and the views are incredible. They cool quickly which is important to me, since I really hardly ever have to deal with dew. In Utah with its seasons that means I can be enjoying my views as quickly as the mirror cools and in the winter that is important to maximize my time in the field. I use them because of these factors and others, and to be honest, they are basic, functioning scopes that were prices right and added my optics to them. Dennis made the scope exactly how I wanted them. I have made them mine by what I have done to them after I received them. I truly believe moving forward, you'll see less traditional dobs and more light weight, non-traditional dobs as space for Millennials in terms of where they live becomes an issue, the need to cool the mirror quickly (they can be impatient it seems, not all, but many) and the desire to set up quickly and tear down quickly. Dennis fills a wonderful niche I believe by offering an excellent product, that is useful, practical and provides great views. I only wonder how long he'll keep going as he is getting into his mid 70's now I believe. Hope that helps. If I think of anything more, I'll reply again.

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    Replies
    1. Anonymous7/13/2016

      Thanks Jay. The beauty of dobs is the ability of the owner to make minor tweaks as they see fit. Even those who have purchased very high end, custom made dobs seem to add their own tweaks after some use. I am leaning to a 14" as well. What is the final weight of your Dobstuff 14"?

      Grant

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  7. Weight of my 14" is as follows (from memory, I have it listed exactly somewhere):
    Rocker Box: 26lbs
    Mirror Box: 36lbs (the 14" is smaller and thinner)
    Tubes: 2-3 lbs if carried together?
    Upper Ring: about 3-4lbs; depends on your spider. 14" is a traditional spider.

    17.5"
    Upper Ring: 8-10lbs (spider is a curved professional/observatory grade, heavy but good)
    Mirror box: 50lbs
    Rocker Box: 36lbs

    The mirror box on the 17.5" is close could be 48lbs to 54lbs. I took the reading I got the most which is 50lbs.

    The 14" is a lifetime scope. If you do a strut and don't want collimation shifts, then do the strings, they help. I never had a shifting issue on my 14" though I did slightly on the 17.5" due to weight I believed. My sling fixed that. I like the plain color of the scopes, and they do look great in the field, but in considering looks, if you desire you can pay more for a stain. I put that money into other things. I felt I had to have the Kydex shell that goes around the mirror. I am constantly walking back and forth to my scope when I sketch etc, and it gets dusty in the desert or in the mountains for that matter. I can lift it out if I want to cool faster but I usually leave it in. I did think of something else I would want Dennis to do. He puts rubber feet on the bottom of the mirror box, and whenever I load the 14" or the 17.5" in the back of my Outback, and scoot the mirror box forward, the front rubber foot ALWAYS comes off. Yes, I want to be able to replace them, but I don't anticipate ever having to do that for as often as I put the feet on the ground. I am not sure if it is better to perhaps glue, or in my mind look for a hose clamp that could lock the rubber feet on while still letting me remove them when I want. Hmmm, I may have to look into that.

    A few more items as I went out and looked at my scopes. On my 14" on the bearings, Dennis use a small screw with a large head, to secure the bearing material. He also glues but the glue on my 14" wasn't done well. I took the screws out, then re-glued the material down again and then put the screws back in. No problem. My 17.5 was fine so I think he has corrected that issue. The mirror cover handled on my 14" was just a knob, and small at that. I have small hands and fingers that are fat and at times it is hard for me to grasp that handle. Once time the cover slipped and went cascading down to my Zambuto mirror. Luckily it just got an outer edge with no real damage. I changed the handle after that. On my 17.5" I have a regular handle and that premium mirror has never had an issue with the mirror cover slipping. Make sure you get a cabinet door handle on your mirror cover.

    My only real compliant is the 17.5" came with the fan support on the bottom of the mirror box loose and I have been able to secure it. I need to take the time this Friday and do that.

    Make sure on your secondary you get a cover for the mirror. I have used the extra socks that come in sheets for my coverings and they have worked great.

    One more popped out and its important. I put felt stops where the mirror box advances to the rocker box in the front of the scope as a bumper. If not you'll wear the wood in the front of the rocker box. I have made that adjustment to both scopes. It means I am a 1/8 of an inch from true zenith, but I am just fine with that as long as the wood is protected. That is something you can add yourself after you get your scope.

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    Replies
    1. Anonymous7/13/2016

      Jay:

      Thanks for the detailed response. I will be following up with Dennis.

      Grant

      Delete