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ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Optical Clarity of Spotting Scopes (1 Viewer)

HI Dd61999,
That is a very nice collection of instruments at your observatory.

What are the last three.
The Ross 7x21. Maybe 21 inch or 530mm f/7 lens?
I don't recognise this. I had several 6 element Ross Xpres WA EMI (Extra Marginal Illumination) 20 inch f/6.3 lenses. They covered 7x5 inch very well and at a push 10x8. They were soft coated internally c. 1955. I sent one to Australia. I don't know if it is still in use.
I had a Ross 24 inch f/5.6? telephoto, but this wouldn't cover 10x8. It went to a photographer doing theatre work using a Pentacon 6.

What are the last two SCTs?
Is 8 inch the aperture or the focal length?

The largest refractor I have is a shortish 135mm aperture, but it isn't good having zonal problems and bad ghosting.

B.
 
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HI Dd61999,
That is a very nice collection of instruments at your observatory.

What are the last three.
The Ross 7x21. Maybe 21 inch or 530mm f/7 lens?
I don't recognise this. I had several 6 element Ross Xpres WA EMI (Extra Marginal Illumination) 20 inch f/6.3 lenses. They covered 7x5 inch very well and at a push 10x8. They were soft coated internally c. 1955. I sent one to Australia. I don't know if it is still in use.
I had a Ross 24 inch f/5.6? telephoto, but this wouldn't cover 10x8. It went to a photographer doing theatre work using a Pentacon 6.

What are the last two SCTs?
Is 8 inch the aperture or the focal length?

The largest refractor I have is a shortish 135mm aperture, but it isn't good having zonal problems and bad ghosting.

B.

Good questions, I am just a casual visitor at the observatory. I knew the large refractor was from the U.K. So when I saw your comments, I went to the webpage to get more info and realized there are even more telescopes I haven’t looked through.

I had no idea they had a 10” binoculars telescope, which I would love to look through. I’ll have to go back soon and be more attentive to their other equipment on hand. Although from memory I believe the SCT were 8 inch in aperture. They had some big SCT's but not sure if they belong to the observatory or if the telescopes belonged to the locals
 
Hi,

not sure if the original poster still reads this or still has the scope in question, but a 664 definitely should be sharp up to 60x with the zoom (unless you got the old 80s style zoom with the rubber eyecup - that one is awful), let alone at 30x.

If you still have the scope please do a star test and take an image of what you see - one can see all kinds of optical problems from that and can then ask Kowa to fix it.

Joachim
 
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