Jupiter GRS with shadow Transit

[Josh Wilson]

I got this image last night with my newly modded Xbox Live Cam.

One would think that if you can get the highest resolution photo then you can get the best image. I've been thinking of going down to the lowest resolution image to get more detail on Jupiter because Jupiter will appear larger on the smaller sensor?. I can also get up to 60 fps at the smallest resolution. Is this logical? Or not?

Thanks for looking

Josh

[Josh Wilson]

I almost forgot the settings...

Frame Divisor=1

Resolution=640x480

Frame Rate (fps)=30.00

Colour Space / Compression=YUY2

Exposure=-7

Brightness=128

Contrast=44

Hue=4

Saturation=93

Sharpness=0

Gamma=180

WhiteBalance=5322

BacklightCompensation=0

Gain=0

[JamesF]

You're doing very well there.

It is possible to calculate the theoretical best setup for imaging, which is basically where the maximum resolution of the scope matches the resolution of the camera. Interestingly that works out to be independent of the aperture or focal length as long as you have the optimal focal ratio. For the Xbox camera that should work out (from memory) as between f/30 and f/40. I went through all the maths of this here:

http://www.tanstaafl.co.uk/2012/03/focal-ratio-capture-length-planetary-imaging/

If you're not into the maths then it's enough to note that whilst this might be the ideal range of focal ratios there are other factors that come into play such as whether the sensor is sensitive enough and whether the seeing is good enough on the night.

If your case it may well be that keeping the image size down is actually allowing the camera to work better by concentrating the light on fewer pixels.

James

[Josh Wilson]

Thanks for that, James. Given that I don't have a barlow (yet), would I be better off cutting down the aperture to increase the F/ratio or should I wait to get my Barlow?

[JamesF]

If you reduce the aperture then you reduce the limit of resolution for the scope, so I'd stick with what you're doing now I think.

James

[Josh Wilson]

Ok, thanks. And how am I getting blue and red/yellow refraction if this is with a reflector telescope? My best guess would be the camera, but I have no idea how...

[JamesF]

The refraction is due to the atmosphere. There's no easy cure for that other than to have Registax do an RGB align for you.

James

[Matt Scunthorpe]

Loads of detail on there. Nice to see the Moon on it as well.