[X] My Assistant

[DDAVIS]

http://www.donaldedavis.com/2002_addons/SSYCOLRS.html

A new set of color samples at the bottom of the page. links to other planetary color related sites as well as to my updated pages concerning Mars.
Any corrections, reactions, etc. welcome!

Don

[NGC3314]

For telescopic observations, I've tried various things with groups at our campus observatory. Many people see more vivid color on Jupiter if I leave the white dome lights on - apparently that puts typical adaptation in a much better place instead of having the eyes try to adjust for some kind of mean brightness including lots of dark space, and get dazzled. This fit with a comment that (IIRC) T.W. Webb made in his "Celestial Objects for Common Telescopes" about 130 years back - that the level of naked-eye detail on the Moon is enhanced if there is a lamp in the field of view at the same time. I concur, using street lights for the purpose - plus it gets more contrast than the daytime view. When it's just at the sunrise line, there are times when you can just about convince yourself you can pick out Clavius as a dimple in the terminator this way.

[JRehling]

I've got 20/13 vision or so, and I have definitely seen the evidence of individual craters on the Moon. Promontorium Laplace also casts an impressive profile which I believe I can see in the right circumstances. That is, you can really notice when it is sticking out into the darkness.

http://farm1.static.flickr.com/109/2609560...00dd14c.jpg?v=0

Keeping both eyes open while observing planets has also been my way of determining the apparent size of the object. I've drawn circles onto pieces of paper that correspond to the image my eye in the eyepiece is seeing. A smarter way, now that I think about it, would be to pre-draw many circles with precision and make find the best match.

If someone wanted to get really crazy, they could make a jpg with the same little Mars illuminated with many color balances, gammas, etc., look in the eyepiece with the right eye and simultaneously scan a laptop monitor with the left eye looking for the best match. Make sure that the graphics program commands the whole screen so that white menu bars aren't disturbing things. Then it would probably be best to switch eyes and see if the same match exists -- it's possible for the two retinas to be at very different levels of dark adaptation at the same time.