Posts Made By: Roland Christen

Lovely! Sharp! Excellent. I would love to see the entire first quarter done at this level.

Rolando

Heavy equipment attached to AP 3600 mount at Dome C. Definitely not carry-on size.

http://e.bondoux.free.fr/imagesforum/t300.JPG

We are also shipping a large number per month, more then ever since we increased our production facility.

Rolando

>>A laser showed that the diagonal seemed to be collimated so I am guessing I need to adjust the objective cell which I believe is threaded on>>

Generally a refractor lens is designed and constructed to be coma-free. This means no matter how you tilt the lens with respect to the optical path, you will not see coma. You will see astigmatism off-axis, but this is not coma.

Therefore, if you have coma in the image, it is not because the lens is tilted, or the lens cell is tilted with respect to the tube. The only way to get coma in a doublet is to shift one of the lens elements sideways with respect to the other element, or to have a wedge in the airspace that exists between the two elements.

The fact that you have coma means that you have one of the above two problems, but you do not have the first problem, which is a tilt of the objective lens or cell. Therefore tilting the cell in the other direction will not solve the coma problem.

Collimation for a doublet or triplet lens means lining up the elements (sideways shift) until the optical centers align, plus eliminating the wedge in the airspace. Both of these are critical. Wedge in the airspace must be less than .0001" or 2.5 microns, and the sideways tolerance is on the order of .0005" or 5 microns.

Rolando

That's a beauty for sure!

Rolando

By the way, today's image by Peter Lardizabal was taken with the 130GTO. http://www.buytelescopes.com/PostComments.aspx?id=38341

Rolando

>>I have a 1959 3" Unitron 155 that is in pristine condition.>>

Post a picture of it. I would love to see what it looks like.

Rolando

>>My questions: Is the haze a result of the oil "going bad" and needing to be replaced?>>

I doubt that the oil is to blame. Hold the lens up to a bright fluorescent light in a darkened room. You will probably see haze on the front or rear surfaces. This is weathering and is impossible to remove by any cleaning method. You will most likely need to repolish these surfaces to get back the original clarity of the glass.

Rolando

Gorgeous

Rolando

Fabulous shot!

Rolando