I've spent a number of nights mulling over the same questions on various optical configurations. As many here will tell you, it all varies by the optical configuration used and experimentation is always the best means of proving it all out. Still, I think much can be learned from others successes (or failures)! Here's my 2 cents worth of experimental results from last night:
Skys were reasonably steady and I spent nearly three hours playing with the same mix of gamma, saturation, brightness and gain while imaging Jupiter with a C11 and a 4x Powermate. The 4x on a C11 using a ToUcam should be a reasonable match, matematically speaking. Though I captured a fairly good image of Saturn using this configuration with a Baader UV/IR filter, I've had difficulty getting good contrast and color results on Jupiter with it. The relative light level is quite low at this magnification. I found it difficult to reach 140 at the K3CCD meter without pushing the gain such that the noise became noticable. I did have a True-Tech IR block filter in at the time.
Conclusion - I saw similar results you post above with regards to various settings and the effects they have on color, contrast, noise, etc. No matter what combination of settings I tried, I still could not capture a decent, low-noise image of Jupiter. The contrast was low and the color looked washed out.
The only thing I didn't get around to before the clouds rolled in was to remove the True-Tech IR filter - I need to repeat the same experiment with it removed. There is quite a bit of opinion expressed here that it isn't needed for Jupiter.
Past results C11, 2.5x Powermate:
I have had good results imaging Jupiter using a 2.5x Powermate on the C11 without an IR filter using the following camera setup procedure:
Set Shutter speed to 1/25th second
Set white-balance to auto
Saturation set to max
Brightness set to ~40%
Gamma ~20 - 30%
Gain set to ~20% - 30% Gain & Gamma are adjusted to optimize the color and signal-to-noise ratio keeping the K3CCD "Brightness" scale around 140. This seemed to work well when stacking the 600 or so frames.
Uncheck white balance
Frame Rate at 5fps
Skys were reasonably steady and I spent nearly three hours playing with the same mix of gamma, saturation, brightness and gain while imaging Jupiter with a C11 and a 4x Powermate. The 4x on a C11 using a ToUcam should be a reasonable match, matematically speaking. Though I captured a fairly good image of Saturn using this configuration with a Baader UV/IR filter, I've had difficulty getting good contrast and color results on Jupiter with it. The relative light level is quite low at this magnification. I found it difficult to reach 140 at the K3CCD meter without pushing the gain such that the noise became noticable. I did have a True-Tech IR block filter in at the time.
Conclusion - I saw similar results you post above with regards to various settings and the effects they have on color, contrast, noise, etc. No matter what combination of settings I tried, I still could not capture a decent, low-noise image of Jupiter. The contrast was low and the color looked washed out.
The only thing I didn't get around to before the clouds rolled in was to remove the True-Tech IR filter - I need to repeat the same experiment with it removed. There is quite a bit of opinion expressed here that it isn't needed for Jupiter.
Past results C11, 2.5x Powermate:
I have had good results imaging Jupiter using a 2.5x Powermate on the C11 without an IR filter using the following camera setup procedure:
Set Shutter speed to 1/25th second
Set white-balance to auto
Saturation set to max
Brightness set to ~40%
Gamma ~20 - 30%
Gain set to ~20% - 30% Gain & Gamma are adjusted to optimize the color and signal-to-noise ratio keeping the K3CCD "Brightness" scale around 140. This seemed to work well when stacking the 600 or so frames.
Uncheck white balance
Frame Rate at 5fps
-Gary
There is only one constant in our infinite universe; it is change.
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