Posts Made By: Mark Brown

HELP ! I know it is not good to clean optics, but I have no choice. I have a couple of achromats with oily finger prints on them, (skin oil) and a couple of large eyepieces, that look like they have oily brush marks on them. (from eyelashes?) It's very nice used equipment that came like this. What is the best way to safely remove this stuff, without effecting the multicoatings. Is there a " best cleaner " or " best cleaning pad " Please help me out here. Thank you very much for any help you can give me. Mark.

Does anyone know what differences there are between micoscope and telescope eye pieces ? Are there different type of lenses inside ? or are they reversed or something ? Does anyone have an idea ? Thank you very much for any help you can give me. Mark

I started off with many pairs of binoculars. Then came the Edmond astroscan, the Meade 4.5 goto reflector, the 90mm meade refractor, and finally my Orion XT-8. All were bought used, at an affordable price. I have recently sold one of my posessions and have the money to finally move up to a more serious performer.(about $3000 to spend, maybe a little more if I have to.) I was always told, aperture aperture aperture. As much light grasp as I can afford. Yhe choice seemed obvious. The biggest Dob I could afford. Until I finally got a chance to look through a 20" Dob. My first impression was, man this thing is big and bulky. My second impression was, I really don't think I like latters all that much. And finally, the faint fuzzies I see in my 8" are much easier to see through the 20", but, I was not that impressed with the back ground glow or skyglow. In my little 8", you get that," diamonds on black velvet" effect. Not with the big scope. Now I'm confused on what to buy. I would like a good scope for deep sky objects, but with the ability to do some planetary observing also. I guess, seeing stars on a black background was more important to me then I ever thought it was. PLEASE help me. I need your opinion. Should I just go with the ever popular 4" apo ? Or would I be better off trying one of the newest craze Russian Mak - CAS or one of the MAK - NEWTs Please give me your opinion. I need it. I have between $3000 to $4000 to spend. (less is better) And I'm NOT apossed to buying used equiptment. I hope you can help me out. Please. Kindest regards, Mark.

I have a few telescopes, and a few pairs of binoculars.
I've always wished I could merge the two. I love the perseption I get with two eyes, therefore I wish I could try binoveiwing, with my scopes. I have a couple of reflectors, and a refractor. All home made. I really can't afford the name brand scopes, unless I settled on one, which I don't wish to do, because I love all of my scopes.
What I do wish to do,is try binoveiwing. I can't however, afford hundreds of dollars for a binoveiwer. What I do have though, is a nice bino-microscope head. I know it wouldn't compair to those fancy, professionally made veiwers, but is there anyone out there that can help me convert, or find information on converting these for use with my telescopes ? What parts I need, how to make them, or who can make them for me, or where I can buy them ? At least until I can save up enough money for a good pair someday. Anybody ?

Does anybody here have any idea what brand of bino head this is, by looking at the symbol on these ?
Anybody ?
If not, know where I might be able to find out ?
Thanks for your time, and any info.
Kind regards, Mark.

Ettore.
Do you have a picture of the eyepiece end , looking in at the eyepiece holders ?

I would go with the high eye relief eyepieces from "Hands on optics" There cheap, have 20mm of relief, provide a good image, and are made by Anteres, I believe, at least that is what I was told on the phone, when I called them. All sizes also on ebay.

Gerry, these make GREAT bino viewers.
They are East German, Zeiss Jenna. Great optics, and coatings.

What seems to be very popular, is to use one pair of good quality, widefield eyepieces, with comfortable eye relief, in conjunction with a few different size correctors, to achieve different magnifications. The zoom eyepieces are also an interesting option. especially the 8 - 24.
Not only is the click-stop an advantage, the longer focal length eyepieces are going to give you the best view.What I mean by this is,if you want high power, it is better to produce this before the prism, than afterwards. The rewards are many, including longer eyerelief, less sensitivity to tiny miscollimations and much lower amounts of optical aberrations due to the long prism path itself. It doesn't make much sense to use 5mm, 4mm or 3mm eyepieces to get up to planetary powers. You will magnify not only all the prism aberrations, but also any image offsets that might be in the eyepiece barrels or the prisms themselves. You may even have trouble merging the image. It makes more sence to use focal lengths no shorter than 10mm, preferably 12mm for high power viewing. Insert a Barlow element ahead of the Bino to achieve a long focal length. This will narrow the beam considerably over prime focus, with the result that the active area for each object beam will occupy only a tiny portion of the prism faces. This will really cut down on aberrations in the optical path. This applies to any Binoviewer.