Instruction: Answer the given question using the supporting document.

Input:
Question: Why doesn't it work with a reflector telescope
Document: Bought this before the end of fall last year. It started to get too cold to star gaze, but I did attempt to set it up once and wasn't successful. Plus you need to buy another set of lenses to make this work. I hope to put it to good use this year.
I'm just a beginner with my telescope, so I don't know of a lot of the little things that experts say about this product. All I know it is great looking at the moon and planets with what amounts to a very powerful set of binoculars! I also love the soft rubbery feeling of the housing.
Having been an observer most of my life, I knew the time had come to buy this. The build quality is very good and I have no complaints. Be aware that you will have to rebalance your telescope when you use this, so while that is not a big deal, it does need to be done. Also this viewer can get into the way of your mount, so you may need to remove it before using a computer controlled slewing system.
Most people really don't need this, but I purchased it due to some vision issues that are coming on as I get older. Being able to integrate images from both eyes can be helpful in improving apparent contrast and reducing eyestrain in older folks. However, buying this also means having to invest in an extra set of eyepieces, so this is a luxury and not a necessity. I suppose being a luxury could be said about having a telescope system in the first place!
YOU CANNOT BEAT THIS BINOVIEWER FOR THE PRICE YOU PAY.I HAVE USED THIS NUMEROUS TIMES NOW SINCE PURCHASED AND THE VIEWS ARE PHENOMENAL. I CHECKED OUT MANY BINOVIEWERS BEFORE PURCHASING THIS ONE AND COULD NOT BEAT THE PRICE AND NOW AM VERY SATISFIED WITH MY DECISION.FRIENDS ARE ALSO AMAZED WITH THE QUALITY AND EASE OF ITS USE.
I am a novice nightsky watcher, I found that one eyepeaces strained my eyes very quickly, limiting the extended of my viewing sesions. I than order the Binocular Viewer and immidiatly felt the relief in my eyes especially since the eyepeaces can be adjusted to different widths. I highly recomended.
Answer: Hello Patty, Honestly I dont know. It might have to do with the total focal lenght, I ran into a problem with attaching a reducer then the diagonal then the bifocal then the eyepiece, and i could not focus properly. You best bet is to call Celestron on Monday, sorry I could not help more, Jim