Quote:
Originally Posted by RickS
A good first attempt! The KAF8300 sensor has shallow wells so it takes some effort to get good star colours (adding some short exposures with HDR is worth trying). Surprising how much Ha you got in 10 mins.
The big dust donut isn't going to be from your secondary. The dust will be much closer to the sensor than that. Here's a calculator that will help you determine where it is:
http://www.ccdware.com/resources/dust.cfm
Cheers,
Rick. |
Thanks Rick,
When I sampled all the bright stars in Photoshop curves -
none reached the top of the curve so I assumed that I had not saturated
any of the pixels - I therefore expected the star colours to be there.
I also ran the recommended gain of 5% & offset of 100.
I just checked all the bright stars on the curves eyedropper function
& they all read 217 out of 255 gray scale.
I checked the same strength levels on a particular medium brightness star on an 4 original RAW frames & I got:
Red = 72
Green = 76
Blue = 70
Lum. = 150
I'll have to think about those results as that's telling me that the stars are actually white.
Thanks for the dust mote calculator link.
I put in correct values & for the giant dust mote
I got 3.029 mm from the sensor.
For one of the small motes I got 0.68mm from the sensor.
That's telling me that I have dust most likely on the sensor itself or very close to it.
I'll check that out.
cheers
Allan