Posted 24 January 2013 - 03:40 PM
It was more a proof of principle - the conditions weren't great. The image was boiling in the eyepiece and clouds were going in and out. It took about half an hour to collect the six images that went into this mosaic (three for the disk, three for proms).
I shot in 16-bit mode with the Flea3. Should this help (vs. 8 bit) in solar imaging? I mostly do planetary imaging with this cam and have to use 8 bit. I like the result so if that is thought to be better, I'll stick with it.
Posted 24 January 2013 - 03:43 PM
Posted 26 January 2013 - 11:03 AM
If you are shooting in 16 bit I would imagine that you don't need to do the proms and disk separately. I can capture both in 12 bit so you should be fine with 16 bit.
Posted 28 January 2013 - 09:30 AM
Tony: It's the Flea3, mono with ICX618 - in other words, the 1/4" chip. I have the GigE version. I know there is a Flea3 with a different chip that is USB3. Just sayin' in the event we have different cameras.
David: that's interesting. I have no sign of the proms on the disk image and on the prom image the disk is completely whited out. Perhaps I didn't really get a 16-bit (or really 12-bit, right?) image?
Posted 28 January 2013 - 10:12 AM
If it is 12 bit or more you should be able to play with your settings while watching your histogram and max/min levels to make sure you don't clip any data and get both disk and proms. That is, stop the disk going white. You might not see the proms clearly in the raw image, but the info is hidden in the shot to be pulled out in processing. You do need to be careful to not set up as you normally would to get the most disk contrast or you will tend to lose the proms. For me, this means keeping the contrast relatively neutral and the gamma not too high or too low (positive gamma best for proms, negative gamma best for disk). I then play with shadows/highlights or selection tools in Photoshop to process the disk and proms separately in the single image. It initially takes a bit of playing around to see what works, but for me it is easier than trying to merge two separate shots. If the proms are very faint then it is probably still best to do two exposures, but for bright to moderate intensity proms, you should get decent results. Good luck!