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Burgess Optical Focuser



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Date: NA
Price: ?
Design: Focusers for both refracting and catadioptric telescopes
Description: Custom built focuser for telescopes.


I purchased my Burgess focuser about two months ago. It has been mounted to a Celestron CR-150 refractor. From what I have seen, most all refractors coming out of the Synta factory employ basically the same focuser. The stock focuser is okay and will suffice for most who simply want to go out and look at objects once in a while and are not concerned with the actual quality of the image they are looking at etc. For those whoever that are, the stock focuser is going to be a source of frustration for most after a time with it has passed. Mine started out being okay but as time passed I noticed it getting more and more "sloppy". When racking in and out, especially with heavier diagonals and eyepieces, there would be image shifting and points where the focuser would seem like it wanted to bind up or drag a bit. Objects would jump about when focusing especially at higher powers. I finally bit the bullet and ordered the Burgess unit. What a difference it made! Like going from a slightly out of tune Ford straight six to a finely tuned Ferrari. This is one beautiful "precision focusing instrument" as Bill Burgess likes to call it. It is buttery smooth in operation and is rock solid from full inward focus to as far out as it will travel, which by the way is about 1/2" further than the stock unit. Now to the icing on the cake. This focuser has a fine focus adjustment knob which allows you to focus so finely you won't believe it until you try it. When you think you have reached as fine a focus as you can using the regular 
focus knob, you simply reach over and tweak the fine focus knob a bit and what was clear as a bell becomes even clearer! The fine focus has a 500:1 reduction ratio which accounts for the ability to focus down on the walls of craters on the moon! Burgess made a special adapter for me so I could use my JMI motofocus with it. This combo is absolutely dynamite. I was also sent a small cable control which attaches to the fine focus knob so you don't even have to touch that knob when adjusting the fine focus. Works like a charm. There will soon be a motor control to use with it also and it will work right along with the JMI unit. Mine is on order now. In a nutshell, this is one of the best made and most precision focusers available on the market, period. There are others out there that cost even more than this one but they cannot be any better made or work any better either. Machined from solid billet aluminum with all brass trim and fittings this unit draws attention wherever I set up my scope. I've even had AP and TV owners come by and walk away very impressed with how it works. It's not cheap at $395 for the 2" version, and more for the 2.7" and 4" models, but it is worth every penny to anyone who wants to have focusing become a joy instead of a headache. Check out the Burgess site at and read about it for yourself. If you are considering replacing that Ford six for a Ferrari, you will be very pleased with your decision to do so. Oh yes, by the way, the 2" version takes all of 3-4 minutes to install. Simply unscrew the 3 screws that hold the stock focuser in the reduction adapter and take out the old focuser. Replace it with the Burgess, put the screws back in and you are set to go. It is fully collimated and will eliminate those focuser collimations everyone goes thru with the stock unit. Congratulations to Bill Burgess for producing a product that lives up to being called a "precision focusing instrument". 

Submitted by Terry Oquinn - - USA - 7/13/200


Anyone looking to upgrade their focuser on their 120mm or 150mm Chinese refractor, look no farther. This has got to be one of the best focusers on the market today. Iíve always wanted one of those super smooth focusers like the ones you find on a Tak or AP refractor, and who wouldnít. Well after many months of looking Iíve finally found one and did not have to spend $6000+ to get one. Astronomer Clint Bach a skilled Optician and telescope builder along with Amateur Astronomer Walter Denton also a Design Engineer and Tool and Die maker with 38 years of experience, have designed such a focuser. It is designed in such a why that all you have to do is remove the three screws that hold the original 2" focuser and place the new focuser in and replace the screws. Thatís all folks.

Now on to the over all design and the unequaled quality of this focuser. This focusing system is a CCD user and astrophotographers dream. The focuser has a fine focusing knob that enables adjustments of the focus tube by .0025" per revolution of the fine focusing knob. This resolution is essential for easy CCD focusing and the advantages it brings to visual observation must be experienced to fully appreciated. There is a clutch assembly incorporated to fix the position of the optical train after adjusting the focusing knobs. This clutch eliminates the drifting problem exhibited by some Crayford type designs.

These focusers are available not only for Refractors but also for Reflectors and SCTís. They are available in 2", 2.7" and 4" sizes so vignetting, in the fastest large aperture scopes can be avoided by proper selection. My CCD work has never been as good as it now is using this focuser. The inside of the focusing tube is as black as it gets, not even the focusers on Tak. scopes are as black. I can not get over the smoothness of these focusers, and I once thought that no focuser in the world could be as good as the ones used on AP and Tak scopes. You never have to worry about how much weight you are going to put on the focuser. I put this to the test by putting on about five pounds of imaging equipment on the optical train of the focusing tube. There was no slipping of the tube at all, and every thing stayed centered. If youíve ever had a hard time with getting that perfect focus for CCD and film work or for visual observing, no more is it a problem. The fine focusing system takes care of that, and when I say it takes care of it boy does it. Iíve never had such contrast and detail hit my eye so hard before when observing deep sky objects and the Planets. As for my CCD and film work, my imaging has never been as good, and I must say I do good imaging, but now its great.

If you want one of the best focuser out there, ask for more info at:  The owner Bill Burgess is a good person to do business with and every question will be answered.

I will be updating this review on this focuser very soon, as I want to get more feed back from my astronomers at the observatory on their testing of this focuser. So far two out of three what to replace the focusers on their $6000.00+ AP 6" APO scopes. As for myself, Iíve found the best focuser to put onto my 6" custom made APO scope.

Review by Don Regan, Director of the Deep Sky Observatory, and also new Director of the Deep Sky Observatoryís planetary section. Main scope is a 12" SCT and two 6" APO refractors and a 9" APO.

Submitted by Don Regan - - New York

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