Log in

View Full Version here: : Mars over Miami 2: use 12 bits or 8 bits?


Doodles23
23-01-2010, 06:41 AM
As Trevor and my wife Gail pointed out, my Jan 20th image made Mars look like it is laying on a slab in the morgue. So I redid a set of 1500 frames taken at 30fps using the 12 bit mode of my new Dragonfly2 camera. This is the image on the left. Does this image capture more detail than the image on the right which was from a set of 1500 frames at 60 fps (8 bit)? Maybe. Maybe not. You be the judge. :shrug:

The awful color was the result of a Photoshop screw-up. Now things are under better control. I would like somebody's opinion on whether it makes sense to use 12 bits @ 30fps vs 8 bits @ 60fps under average seeing with a bright planet? I am under the assumption that the larger grey palette at 12 bits only becomes important with dimmer images that will have to undergo stretching.

Quark
23-01-2010, 11:48 AM
Hi Dave & Gail,

I reckon the colour is an improvement, as for the difference in detail, frankly they look the same to me. The detail in your new attempt looks slightly sharper, but it is at a smaller image scale.

Any image will look better resolved at a lesser image scale.
I think Bird or Paul would be the ones to talk about the pro's and con's of 12 bit & 8 bit but I recall Bird saying that he was going to be away for a while.

Regards
Trevor

davidpretorius
26-01-2010, 01:12 AM
Hi Dave, nice work

I always use 12 bit on my lu075m with Lucan recorder/

For my 10" scope, 30 fps is a nice rate to get the data down the pipe and record roughly 35 seconds each channel at good histogram exposures.

Cant say I can really point to a good example where 8 bit is compared to 12 bit, but in theory, you should get a better result due to the number of gray scales/