NGC 300 - longest integration yet attempted

[thegableguy (Chris)]

Around 3 1/2 hours' worth in total, taken from two nights (Mon & Wed just past).

Mon was 14 x 4-min exposures at ISO 400; Wed was 49 x 3-min exposures at ISO 800.

On Monday my alignment was pretty terrible so the guiding was struggling. On both nights the collimation was off.

Flats, darks and bias used, however there were some corners cut; I used older master darks with the right ISO but shorter exposure times (my intervalometer died last night). The flats may *possibly* be from another, different brand 8" f/5 Newt, not 100% sure.

I'm reasonably happy with it; it's pretty noisy, but I'm not expecting much from my little D3300 considering what I paid for it.

My main complaint is that I don't really know what I'm doing with DSS. Once the TIF is created I'm reasonable at editing it, but I'm sure there are better ways to stack than just leaving everything at default settings. This is the first time I've tried combining different ISOs & exposures.

I also don't know how to tweak it in Photoshop. I know my way around Photoshop for portraits but this is a VERY different game and I don't really know what tricks to use.

Any tips very welcome! Thanks for viewing.
~C

[Somnium (Aidan)]

best yet, galaxies are a tough target for DSLR imaging.

[thegableguy (Chris)]

Originally Posted by Somnium

best yet, galaxies are a tough target for DSLR imaging.

Thanks mate. Yeah I'm learning that fairly rapidly...!

[mikeyjames (Mick)]

Hi Chris,
This looks great. I hope one day I get there.

A quick question. Whenever I ty to do an exposure longer than 8-10 seconds it looks really washed out with skyglow. How do you deal with this with longer exposures?

Thanks
Mick

[thegableguy (Chris)]

Originally Posted by mikeyjames

Hi Chris,
This looks great. I hope one day I get there.

A quick question. Whenever I ty to do an exposure longer than 8-10 seconds it looks really washed out with skyglow. How do you deal with this with longer exposures?

Thanks
Mick

Besides light pollution / lunar cycle etc, it's all about the processing. Even with my better than average skies and no Moon, my individual subs don't look like much at all - very washed out and you can barely tell there's a galaxy there... but after stacking a whole bunch of subs with darks flats etc the resultant TIF has a huge dynamic range, from which you can pull quite a lot of detail if you know how. (I only sort of know how! Need to get better at it.)

[ZeroID (Brent)]

Originally Posted by mikeyjames

Hi Chris,
This looks great. I hope one day I get there.

A quick question. Whenever I ty to do an exposure longer than 8-10 seconds it looks really washed out with skyglow. How do you deal with this with longer exposures?

Thanks
Mick

Levels and curves in Photoshop ( or your preferred Graphic program )
With particular attention to the r (red) channel in levels to start with.

[RickS (Rick)]

Congrats, that's a nice result.

[mikeyjames (Mick)]

Originally Posted by thegableguy

Besides light pollution / lunar cycle etc, it's all about the processing. Even with my better than average skies and no Moon, my individual subs don't look like much at all - very washed out and you can barely tell there's a galaxy there... but after stacking a whole bunch of subs with darks flats etc the resultant TIF has a huge dynamic range, from which you can pull quite a lot of detail if you know how. (I only sort of know how! Need to get better at it.)

Thank you. I've had a bit of a play with PaintShop Pro this morning and did make some things look better. Photoshop has always seemed complicated but I guess I'll need to learn it for best results.

[mikeyjames (Mick)]

Originally Posted by ZeroID

Levels and curves in Photoshop ( or your preferred Graphic program )
With particular attention to the r (red) channel in levels to start with.

Thank you.