Formal Review of Dobstuff 14 inch with Zambuto Optics

I have been swamped! After pneumonia, I still have a lingering cough that I am going in for on Friday afternoon to find out why I still have a chronic cough! Next, both work and my own courses are keeping busy as are family commitments. Last, the weather over the last 3 months here has been less than favorable and that has extended here into October. Okay, let me qualify that by saying the weather over the last couple of days has been wonderful. Of course that is during the full moon period. I am hopeful to get a full session of four to six hours in with Daylight Savings time allowing me to observe from 6:30pm until around 12:30 or 1:00a.m.

So, as I have recorded here, I got my new 14 inch Dobstuff telescope and I did manage to get it out a couple of nights under dark skies.  So without any further ado, here is my review of this telescope, along with pictures I took in the garage. Sorry, my SD card was full when I got out to the dark site so I couldn't take pictures. The ones here are from my garage. First is the assembled scope with the Telrad on its riser and the 9x50 finderscope off.  You can see the large bearings that Dennis provided that ensures wonderful motions with the ebony star on them.  The struts are around 53 inches long I believe and make for an easy insert into the lower OTA. They are both attached to the bearing by a a wooden clamp that has a bolt that loosens and tightens the strut so you can fit it through. The struts screw into the bottom OTA.  If you look closely you can see the counterweight that Dennis provided but which wasn't enough for some of my eyepieces. More on that latter.

Here is the scope looking from the upper OTA where you can see the twist bolts that attach the upper OTA to the top and where I have a dew heater attached to the secondary.  Here you can see the clamps that connect the struts to the alt bearings and the mirror cover.  The build of the scope is wonderful.  I like how the counterweight easily moves up and down the strut and the same would be true for the 9x50 finder scope if I had it attached.  The most important one to move is the counter weight. As I attach a shroud to this scope, it will be critical to allow for enough movement to move the counterweight when I need it and then ensure the shroud covers that up. I have two embroidery hoops coming that should allow me to attach one just down from the focuser, and another about half way down that when combined with some bungee type cords will keep the shroud from falling into the light path.  The shroud won't go to the wooden part of the upper OTA here, but it should work well allow me access to the parts of the scope I need. With the secondary heater, I am not afraid of dew and as I don't run into dew except at one observing area.  I want the shroud to mainly protect the mirror.  My wife plans to use Velcro (we got the type that irons on which she feels will work better as we make the shroud in 3 sections.  As soon as the hoops arrive we will begin construction.  Now having said that, in using the scope, even with a 14 inch Zambuto mirror, I am not afraid of dropping stuff on the mirror.  I have never dropped anything on my old XX14i shroud and the open design here should help me to cool the primary rather quickly.  I'll make the shroud, but we will see how often I use it. Yes, that is Pepsi Max and Diet Squirt on the bench in the background. And yes, I have an older style grinding table I need to modify to grind some mirrors I have and that is another project for this winter.

Here you can see the upper OTA with the spider and the secondary.  My secondary mirror, after centering it , is still loose and I need to use the Bob's Knobs and the central bolt with a spring on it to tighten down the secondary mirror a little more.  The design of the upper OTA is a wonderful design in my opinion. It allows for open access to the secondary, with the spider in place and easy installation of the struts. Unlike the XX14i which as an awkward attachment, though I never had a problem, Dennis design is wonderful. I install the struts to the bottom OTA, and then to the upper OTA and then tighten them down.  The wood work on the upper OTA is terrific with no flaws showing.  The focuser, a 2 speed Moonlight is as smooth as a baby's backside  It's mounting allows for quick work for focusing and using.  The Telrad is a little bulky, and I may replace the 4 inch riser with a 2 inch riser, but for now, it works absolutely perfectly.  I just have to adjust to using it with my left eye over my right eye but that is coming. I do highly recommend a secondary mirror dew heater because of the openness of the design that Dennis uses.  I need to use some black electrical tape to secure the white dew wire to the spider and then so it can easily access either my 2 six volt batteries or my one 12 volt battery that I will use to run it via my Thousand Oak controller.  If you live or observe with dew, then you need one in this design. For me, that means fall and winter when I face not the dew others face in the MidWest or the Eastern United States, but the frozen dew I face during these two seasons.  Funny, since I have purchased or made my dew heating system (its a combination) I haven't needed it that much.  Hmmm. . .

This picture shows the mirror cover, the sliding counterweight , the connections between the alt bearings and the struts and the dew cover that fits into a wonderful groove that Dennis makes if you get this feature. Now the Zambuto 14 inch I have in here is no way as thick as the 2 inch primary that I had in the XX14i.  The brand new mirror is 1.4 inches thick and weighs significantly less.  However, I am not afraid for where I live and observe of the primary dewing up on me. I did want the dew cover though to protect the Zambuto primary as I observe.

The rocker box is wonderful, the only flaw I found was a small dent in the very bottom of the box that wasn't filled in and sanded prior to the coating. This is the same on the hole in the middle of the Alt Bearing on the right in the picture. There was a small flake where the wood broke away slightly when the screw went in. This wasn't filled and sanded and only distracts from the visual view of the scope but in no way impacts the operation of the scope which is tremendous. I am picky here. When I made my chair and was finishing I filled the holes and flakes of wood that had occurred during the build, sanded them down and then applied my coatings.  Again though, not a big deal, but I would mention it as the only slight critical evaluation of the scope. Overall the build quality is fantastic, and Dennis does an outstanding job. Also, in this picture in the bottom OTA you can see the two metal holders where the wired strings attach to ensure that there is no flex in the struts from horizontal to zenith.  Personally, if you are getting a scope under F5, I would recommend going with the strings over the travel version, though the argument could be made that a travel version is better since the struts probably won't flex with such a low F ratio. For my scope, ensuring no flex was more important than a travel version because I want to maximize the the views the Zambuto gives so I can sketch. From what I've seen, having the wired strings ensures absolutely no movement and if collimation is spot on using my Catseye System, the view of the DSO's were beyond description.  The travel version would help one to travel in a smaller car (I use a Pathfinder SUV) and allows for the strut poles to not be as long if I understand it correctly. This is something each purchaser from Dennis will have to decide which way to go after consulting with Dennis.

Here is a view of the left Alt Bearing. Again, there is Ebony Star on the actual Alt Bearing and on the bottom of the rocker box are the Teflon pads that ride on a orange peel like substance that I am guessing is like FRP Wall Board as you can see at this link. I have the counterweight all the way down and you'll see why soon.

Here is the right Alt Bearing and a close up of how strut is connecting to the Alt Bearing, and the clamp for the 9x50 Finder which I hadn't removed at this point.  The beauty of this design ensures that I can use this scope with a quick cool down with premium optics.

Bottom of the mirror box with the modified mirror cell from the XX14i, the three new collimation screws and the rubber feet so that if you remove the mirror box from the rocker, you can put it on the rubber feet keeping the structure off the ground. Wonderful adaptation. An even better adaptation is Dennis has removed the locking screws from the Orion mirror cell. I and my friend Mat who has been ATMing for 17 years or more see no reason for the locking screws. If the mirror is secure, there is no need for the locking screws.  You can see the back of the mirror and the mirror completely covers the opening in the back so there is no need of a baffle here.  I put a mirror on the back and with the way it is mounted, there is no vibration. To be honest though, I haven't had to use it so far except in the backyard one time.  I am hoping that changes this next Friday. You can see the Ebony Star here on the Alt bearings and you can see the outstanding quality that Dennis puts into the scope.

Now here is where I ran into problems.  This is the Explore Scientific 30mm 82 degree eyepiece. It's a monster at just over 3 lbs if I remember correctly.  When I put this on the scope the counter balance went out the door! Even trying several positions with the 1 1/4 counterweight I just found I couldn't use the scope. Well, its not quite a TeleVue 31mm Nagler, but it is close and I REALLY like the views from this eyepiece. So much that I knew I had to figure out how to make this happen. So I left the Telrad on, removed the 9x50 RACI finder and would use the ES 30mm 82 degree or my TeleVue 27mm Panoptic as my finder eyepiece.

I struggled to figure out how to get this to work when I remembered something I had purchased to help for balancing the old XX14i or the XT10 I own. So I went to my office, pulled out the two 2 1/4 pound ankle weights I had, attached them using their velcro around the end of the truss poss and yes, when the eyepiece was in, I had no balance issue. However, when I took the eyepiece out to insert a new one, say my 10mm Pentax XW, the scope was largely out of balance and I would lose the object I had found in the 30m ES 82 degree. So I removed one of the ankle weights and it seemed to help.

Dennis reading about this sent me an email and made and sent me at no cost two more 1 1/4 lb counter weights to add to the one I have. That is 3 3/4 lbs and that should more than balance the scope. I haven't had the weather or time to try it but I am looking forward to a trial run perhaps this Friday or Saturday in the backyard again.  I expect that this will resolve the issue and is just one of those things of getting use to a new scope.  Again, not an issue, Dennis helped me out but one if I am solely using the ES 30mm 82 degree I could have solved with the ankle weight as shown in the picture below.  The counter weights are the major difference! Thanks Dennis for again, showing outstanding customer service.  You can see the dust from using it the night before (its been wiped out now).

So, how please am I with my new scope? Extremely pleased. I have thought for 2 years now whether to go with Dennis or another Telescope maker. I choose Dennis because of the open design of his telescope, and for the quality and quick turn around he offers.  The other maker would have meant a year long wait, and I had waited long enough. Do I feel I lost something by going to Dennis? NO WAY! The build is excellent, and the quality superb and the motions are outstanding.  This scope surpasses what I had in the XX14i by light years. Don't take me wrong, the XX14i was a good scope and I used it extensively 3 to 12 times a month for over 2 years. Yet it was starting to show the wear and tear of that use and I feel now I have a scope that will last a much longer time and one that as I want, I can modify and play with as I want.  Here is my final review:

Transportation:  The mirror stays in the rocker box, is stable in the car. The three strut poles fit nicely either laying across the back seat or if I want to lay the seats down, I can fit them on the side. I do need to make a carrying case for the strut poles so they don't scratch up as much. The only thing I need to figure out is how to comfortably transport the upper OTA as the secondary is sticking out. I have tried to see if it will fit on top of the mirror box but that hasn't worked. For now I lay it on a seat (I fold 3/4 of my back seats down, leaving one seat up) with nothing near it.  Weight is another huge saver as this scope is so easy to move.  The rocker I can carry by one hand if I have to and the mirror box, though still a two handed job doesn't break my back like the XX14i's lower OTA did.  So for ease of transport, 9/10 (just need to figure out the upper OTA and then I'll change it to 10/10, but this is more my issue I believe).

Setup/ tear down - Setup takes 10 to 15 minutes, realizing I'm still adapting to the scope. I pull the rocker out of the car, put in the mirror box, drop in the struts and secure them, attach the Telrad base to the strut I want to have it on, the 9x50 IF I want it (need to make a lighter one), put on the sliding counter-weights.  I then attach the upper OTA to the struts, attach the light baffle that Dennis included and works wonderfully (I am adjusting just a little), collimate with the Catseye System and I'm ready to go! Tear down is even quicker! I am also making a removing pad though that will go around the struts when I remove them in cold weather so my hands aren't frozen (yes, I wear gloves, but for break down it can be more like the lining I wear under the gloves so I have traction).  Score: 10/10

Telrad: Works well, no problems outside of weight. I may move to a Rigel Quickfinder (someone not knowing what they were at one of Mat's ATM sessions called it a Telrad 2 so now we call it that with affection and a term of endearment).  8.5/10 (not scope issue here, I am thinking the Rigel might be a better piece of equipment on a scope like this just due to the weight difference).

2", 2 speed Moonlight Focuser.  This focuser is a joy to use. I'm sure it adds weight to the OTA, I love this focuser and it is a keeper.  It focuses precisely, and holds focus every time.  It has a very precise hold on the eyepieces, thus keeping the eyepieces well aligned with the scope. The only thing I didn't like is that my 27mm Panoptic lips drew the brass compression ring out of the structure. I was able to insert it but I would think for the cost, this wouldn't happen. Again though, I think this is part of my learning curve. We'll see over time. Focuser: 9/10 Brass Ring popping out I didn't expect and my heart sank until I realized I had grasped it and it wasn't heading toward my Zambuto primary!

Upper OTA Design. Works outstanding. The Spider is a 4 vane system from my old XX14i and works just fine here with a minor adaptation from Dennis.  There is a spring and central bolt that helps collimation and I have Bob's Knobs on the scop. I just need to figure out how to make the secondary more secure so that after observing, it doesn't move around.  That is how my old XX14i was, how the 20" Obsession is.  I may email Dennis for advice on this one.  Again, not a problem with the design, just my learning curve on the scope.  The Baltic Birch here is beautiful as is the entire design.  10/10.

Struts:  - These are as solid as iron and the ends work quite well. I am close to figuring out which strut is the best fit in each section so when that is done, I'll number them so they can't be seen and set up will go even more quickly. The virtual spring truss made of wire are absolutely what I wanted. There is not flex in the scope.  10/10

Collimation: Due to the virtual springs collimation is easy and with the Catseye System, dead on. This ensures that the Zambuto primary is giving its absolutely best views when observing. 10/10 No variance once I am done, I don't have to redo that night. 10/10 (9/10 until I can figure out how to secure the secondary).

Mirror box - I am extremely pleased with the mirror box, the dew shield, the mirror lid and all that goes with it.  The box allows for a quick cool down, even without the fan, the dew shield protects from both dew and those pepples and sand in the desert and mountains where I observe, and the mirror cover is wonderful to protect the primary.  10/10

Mirror cell - The mirror cell works wonderfully.  It is the old, 18 point mirror cell from my XX14i minus the locking bolts and I haven't had a problem. Mat has suggested a slig around it, and I will probably add that just to make me feel secure with that investment.  Collimation bolts work great and are much easier to use than the Orion or Chinese systems I've done.  Rating: 10/10.

Mirror cooling -Not a problem here. The openness of the mirror box and cell ensure a rapid cooling and if I engage the fan, that only helps. Dennis design for what I wanted (quick cool down to maximize viewing time) nailed it. 10/10

Rocker box and baseboard. Wonderful design, light weight enough to easily move, strong enough to support the scope. Only critical were two pieces of wood work I personally would have filled and sanded but that is me. See, I have to nick pick to really find issues with the scope.  9/10 because nothing is totally perfect! ;)

Vibration - Not an issue. None. 10/10

Baffling - The baffle across from the secondary works great.  I will be adding a shroud more to protect the primary though I am getting very comfortable using te scope without one and this build truly doesn't need one. In truth, this scope has made me more aware at the scope than any other scope I've used and that is a wonderful thing. I make sure everything is done right.

Motions: Altitude is a charm, never a problem. I did have a problem in azmuith that it took an initial bump to get it to move, but then it was like butter. I added some Pledge Lemon Oil to the bottom and that worked wonders to the point it is not an issue.  9.75/10

Mirror: Okay, if you've never owned a Zambuto Mirror then your missing a lot! The contrast in the mirror for me is one of its key features. That contrast brings out more detail that I have seen in any mirror save one or two perhaps,made by my friend Mat.  I know that M103 was just downright STUNNING as the Blue Giants, the Red Giants and the oranges and yellow stars just popped out of that cluster. M31 from a dark site! My eyes were bulging out as I saw dark lanes, globulars and bright HII regions far easier than I ever had before. Faint objects? Yep, more contrast means more detail in my experience so far. The mirror was more than worth the weight and the cost.  Now I just need one good night to get out under the stars and really work the mirror and the scope. I need to spend 4 to 6 hours working a list quite hard, sketching quite hard and going there. The mirror scares me because I think I may have to start over and redo over 1200 sketches I have! Thank you Carl and Chuck for the outstanding and unbelievable product you provide and deliver. You make a huge difference to those who view through your products I believe. Rating: 15/10! if not more.

Build cost - I believe the cost for this scope (the structure) from Dennis would be just over $1800.

Overall Rating: I have to give the scope a 10/10.  There are a few things but those are more my issues than Dennis's build. I am having to adjust to a new scope and that takes time. The scope is wonderful and for the cost, offers one of the best values out there. Dennis' customer service is second to none. I have another good friend who has ordered a premium scope well over a year ago and has only heard from the builder two or three times. I had no such communication problem. Dennis and I talked via email daily and Dennis kept me entirely in the loop.When I wanted one thing different than his recommendation, he went with what I wanted. The turn around time was also tremendous, just over 5 weeks I believe to get the scope.  I have a new quality mirror and a quality first rate structure to house it and now just need the weather and my schedule to cooperate.

So, if you want a quality build scope, with the highest quality build and motions, and yet don't want a huge lag time, Dennis at Dobstuff is the way to go. I am glad I went that direction and I know there are many out there who are also glad.  Your build will last far longer than a Chinese scope, the quality is worth the build and to be honest, after I refigure my XT10's mirror, I think that scope is going to be off to Dennis for anoher remake!  Dennis, thank you for your patience, your communication, the outstanding craftsmanship and quality that you provided. I'm proud to be a Dobstuff owner!

So those who have gmail are aware, I created a hangout for Dobstuff owners or those who may want to be where we can hangout and chat via video or chat, answer questions etc.  Email me at JayLEads at gMaiL doT cOm with your gmail account and I can add you to the circle. I think you can add yourself since the Circle is public. The name of the Circle is Dobstuff Owners.


  1. Anonymous11/01/2012

    Good, detailed review Jay!

    I am also impressed by the scope. The views were outstanding that night in your backyard, and the motions of the telescope were far superior than your original 14".

    I fully expect you to get many years of great enjoyment out of that scope.


  2. Wonderful review. I think you are in love with your dobstuff more than I am with mine ;). I will agree that his scopes are close to perfect (a few small issues, as you've mentioned), but all the important stuff are done right. One quick comment about the shroud. The more I observe, the more I'm convinced a shroud is necessary -at least in the areas I go to- where stray light can be an issue. I'm looking forward to getting mine from Heather at Scopeshrouds.

  3. Yes, the important stuff is done right and that is the most critical. I can tweek the other stuff myself and no dob is a finish project, they are just that, a project. If I were observing in my backyard I might consider the shroud more necessary, but where most of my observing is done at a dark site locations (weather allowing). I am still proceeding to make my shroud with my wife's help, and the two things I am waiting for are at the post office so my son will pick them up tomorrow and then we'll go from there. November is very busy so it may not be til December til we get to making the shroud. I would be very interested in seeing what Heather does for you.