M42 and NGC 1977 re-process

[Carole]

This was my image from 31.1.2010 my first guided image (as we all know slightly out of focus but good enough to practice processing on)


Reprocessed using some new processing skills, including RC astro gradient Exterminator, separating levels and nebulosity, and also including some shorter images which I took in November to try to reduce core over-exposure). Bit too pink maybe?


I also thought I'd have my first go at NGC1977 while I was at it.


Still room for improvement, but Rome wasn't built in a day.

[MarkS]

Carole,

You've made a good job of the core but I think something has gone wrong in the outer faint "wispiness" which has become noisy and "posterized".  Previously, though noisy, it wtill looked quite smooth.  One possibility is that you're desampling down to 8 bits a bit early?

Mark

[Carole]

One possibility is that you're desampling down to 8 bits a bit early?

You're absolutely right there Mark.  Unfortunately the version of Photoshop I have does not allow you to do a lot of the processes in 16bit, so it's very annoying I have to change down to 8bits at an earlier stage than I really want to. 

I think I need to try to get myself an more up to date version of PS on my desktop.

Carole

[MarkS]

Your explanation makes sense.  It's really important to do the whole processing sequence in 16 bit to avoid exactly those effects you are seeing.

[Mac]

What version do you have??

[Carole]

I've got PS 7 on my desktop.  I think I've got CS3 on my laptop but I don't really like working on laptops except when there's no choice, guess I'll have to do so until I can upgrade my desktop.

Carole

[Mac]

ps7 allows full 16 bit editing.
have you selected the 16bit mode?

[Carole]

It's always in 16bit mode after stacking, and will only allow me to do some or two things

Will allow:
Levels
Curves
Some filters inc High pass

Won't allow:
Marquee and cut/copy (therefore cannot make any layers)
Select and copy
select colour range
Desaturate
selective colour
Replace colour

I guess it's the cut/copy/making of layers that is the real pain.

Carole