Which has better contrast?

[Canopus Lim]

http://img511.imageshack.us/img511/7069/funly9.jpg

I have done a simple (quite ugly ) drawing of #1 Jupiter and #2 Galaxy. This is to simulate what is seen through an eyepiece. In A, it shows the view with a dark sky background and lower brightness of the object. In B, the background is brighter but has also brighter object.

The question is....which one has better CONTRAST?

My definition of contrast is Signal to Noise Ratio (SNR). It is the ratio between the brightness of the object and the brightness of the sky background. Therefore i would pick 1B and 2B as having higher contrast even though the background is not as dark. In my opinion, a higher contrast view is one where details are better seen.

How about you all? Which would you pick as having better contrast?

[rcj]

this is a rather interesting question, canopus. was rather surprised there was no takers for this yet. anyway, I would choose 1B and 2B as well, where like u said there are greater expected details to be seen during those simulated conditions. However it may not agree with having a better "accustomed" view as it does not have a "black" sky background, which to some, it may be more pleasing (and yes, it is rather subjective). Of course, it would be perfect to have 1B and 2B and with a black background. I would also like to add to my version of contrast definition with an additional clause that states "the quantisation levels between the shades from black to white are more distinct".