Denkmeier Binotron 27 Super System Review

By: Vlad Fedosov


My binoviewer journey began years ago when I bought a used Meade LX-200 8” classic that happened to included a binoviewer. The bino looked like a quality unit, but I’m not sure that I ever figured out who it was made by. One thing that I did quickly figure out is that I was hooked on the comfortable, more detailed views of the planets! Since then I have owned a standard Denkmeier(Denk), two Denk II’s, and finally my current Binotron Super System in my quest for the perfect binoviewing experience. My Binotron Super System is the top of the line model that includes the D21 eyepieces, OCS, power switch, and filter switch. So how does the Binotron Super System work out in the field, and is it worth the price? Let’s dive in and find out!


I have used the Binotron on many, many nights of observing for both planetary and deep sky objects. I have also used it in all the major telescope designs including refractors, SCT’s, and dobs. This review is the compilation of my thoughts on how I feel the Binotron performs in the real world, and how I find that it fits into my observing style.

I will start out by discussing the most obvious and most common use for a binoviewer witch is planetary observing. I guess I kind of gave up my opinion on binoviewer and the planets in the intro, which is that in my humble opinion there is no substitute for the comfort and the amount of detail that a binoviewer will show on the planets. I say this even though I do sometimes prefer to use my 5” APO fitted with an Ortho eyepiece for that ultra-pure view of the planets(I always compare it to a religious experience). But when I do reach for my Binotron, I always see at least as much detail and in most cases more! Again I think that the main reason for this is that it is just so comfortable to observe with both eyes. I also really enjoy the power switch for planetary observing as I find that I can adjust to the seeing a lot quicker by just going either up or down in power as conditions dictate. The filter switch is also a very useful tool for planetary observing as you can have two filters preloaded and compare the filtered and unfiltered view very easily and quickly. With the filter switch, you do need to keep in mind that you will likely need to switch out filters depending on the planet being observed. Russ does sell additional 2” and 1.25” filter holders which make this task much easier and enjoyable(I typically have light pollution reduction filters loaded in one set of holders, and color planetary filters in a second set). The filters are not too difficult to change in the holder as they are held with some set screws but this is not something you will want to do in the field.

Another category of objects that I enjoy observing is double stars. This is my object choice when I’m in my light polluted backyard and have no planets to observe. I have tried on many occasions to compare the view that I get with a binoviewer vs a single eyepiece and for some reason I do prefer the single eyepiece view to a binoviewer on doubles. I think for me this is just a personal preference as I also really prefer the view of doubles in a good refractor to any other scope design.

Moving onto deep sky observing, this is really where the Binotron shines and one of the primary reason I wanted to upgrade to it from the Denk II. The Binotron utilizes 27mm prisms and Dielectric Coatings so that you can attain a very wide, and bright field of view(FOV) without having vignetting. This is especially the case when the Binotron is mated with the d21 eyepieces. I find that the d21’s are excellent performers and more comfortable to use than my old 20mm Explore Scientific 68° eyepieces. The views of DSO’s with a binoviewer compared to a single eyepiece is a subject of some debate. From my personal experience, I believe that most of this debate is due to folks using entry lever binoviewers with prisms that are small and inefficient. The Binotron produces images that at least equal a single eyepiece view on all but the very dimmest DSO’s! In most cases, in fact, I find that I can see more detail on DSO’s with the Binotron then without. This is no doubt the result of the fact that it again is much more natural and comfortable to see anything with two eyes. The added benefit of using a good binoviewer on DSO’s is that it really does give the object a more 3D look. I also hear a lot in the astronomy community that a binoviewer is only a toy for big scopes especially when it comes to DSO’s. While I do feel that really anything will look better in a larger scope, the Binotron is marvelous to use on larger DSO’s from a dark sky site on objects such as the Pleiades.

I will never forget the first time I saw m13 through the Binotron at high power mode with my Meade Lighbridge 16”. It was like I was flying right past it in a spaceship, just a magnificent view! Another very memorable observation was made with a new to me 18” Obsession clone. I was using the scope for the very first time in my light polluted backyard and had m57 centered in the Binotron in high power mode right when it was overhead. I could not believe my eyes that the central star was right there in the middle of the ring in plain sight! Now I think that I might have caught glimpses of the central star in my old 16” but I was never 100% sure. This time with the combo of the new 18” and the Binotron, it was unmistakably and easily seen.

The overall mechanics, fit and finish, and quality of the Binotron is second to none. All of the components are made to a high tolerance and nothing feels “cheap”. I particularly like the fact that it comes with high-quality metal caps all around. Both the filter switch and the power switch work as advertised, and I do feel that they make my observing time more productive. One of the major features of the Binotron over previous generations is that the unit is easily user collimatable. I have had to do this when I first received my Binotron(I bought it second hand) and it is as easy as pie. The hard case that the binoviewer comes in is of good quality and I like the fact that it has room for a set of eyepieces(I would prefer if it was black and not green). My only real complaint with the Binotron is that it is heavy! I really do not think that there is much to be done about this as from what I understand it is already made mostly out of aluminum. I do not have an issue balancing it even with my 80mm refractor, but I do need to use a longer than standard dovetail bar. I have had to get help from Russ on a cap that I lost, and he was more than willing to help replace the item at no cost to me! That is customer service! It’s a pleasure to know that you can reach out directly to the owner of the company for help.


Overall, I’m very impressed with both my Binotron Super System and the service that I have received from Denkmeier. If you are someone that is new to binoviewers and have the funds for a Binotron or someone that currently has an entry level unit that is looking to upgrade I would highly recommend it! I strongly believe that if you give observing with two eyes a serious try, you will be quite surprised by what you were missing out on!