Read noise?

[swlloyd3]

Hi,

Does anybody know what the little diagonal lines are in this image? They seem to be consistent across the whole picture but just wondered if this was read noise or something else?

Noise.tif

[pete_l]

My guess would be either tracking errors in one or more subs, or internal reflections from somewhere inside your imaging train?

Is it possible that the scope hadn't finished slewing before the first sub was taken?

[swlloyd3]

Thanks Pete,

I have checked each sub and there does not seem to be any tracking errors on any of them - I thought it was tracking to begin with due to the fact it looks like small stars 'wiggling' around a bit during the exposure but there are a lot of stars that do not show any movement and it seems consistent across the frame.

I have loaded a single sub into Photoshop to examine and cannot see the same pattern once stretched, do you think it could possibly be something to do with the way they are being stacked? 

ste

[swlloyd3]

Ok I have solved the issue it was to do with the stacking settings! Phew! looks much better now... I will be posting the full picture in the forums very soon!

Thanks again for the help! 

Ste

[msh1]

i get the same problem how did you fix it

cheers

[swlloyd3]

Hi msh1,

This seemed to have been an error with the stacking. I played with the settings and it disappeared. Obviously I don't know what type of image you are getting the same error on but when you are about to stack go into the recommended settings and select all suggested settings (there is a handy little description next to each one).

I had to change 1 or 2 that were not selected and it sorted out the issue with the frame.

Thanks,

Ste.

[msh1]

Hi msh1,

This seemed to have been an error with the stacking. I played with the settings and it disappeared. Obviously I don't know what type of image you are getting the same error on but when you are about to stack go into the recommended settings and select all suggested settings (there is a handy little description next to each one).

I had to change 1 or 2 that were not selected and it sorted out the issue with the frame.

Thanks,

Ste.

are you using dss I'm using nebulosity 3 i get the same marks now and again not been able to fathom out why

[swlloyd3]

Yes DSS. I looked back at one of my old horsehead edits and can see the same defects. I think it has something to do with shooting in Ha and not using the correct settings on DSS because when I edited the horsehead I think I just used default settings and not the recommended for Ha.

Ste