Yeta-nother Eta Carinae nebula

[Camelopardalis (Dunk)]

Can we ever have enough of it

This was my first experiment with exposures of this kind of length, using my little WO Zenithstar 71mm (with reducer/flattener) and Canon 1100D on an EQ6 at SPSP. While unpacking my stuff back at home, I realised I hadn't used the spacer between scope and camera

15x 20s exposures, stacked in DSS, then tweaked to enhance the colours. I'd like to try longer exposures next but not sure what I should expect from my mount

Any tips/feedback appreciated!

[cometcatcher (Kevin)]

That's very nice. With a little 71mm and reducer you could easily get 2+ minutes with good PA.

[LightningNZ (Cam)]

Very nice, very wide field you've got there. What's the final focal ratio?
-Cam

[Camelopardalis (Dunk)]

Thanks guys!

I'll look forward to practicing longer exposures the next time I'm out of the City for sure

The scope is f/5.9 native and the reducer is 0.8x, so around f/4.7-ish. Not sure if it is altered by lacking the spacer, but I'll try some similar shots someday to see.

[raymo]

Yes, very nice Dunk, what ISO did you use?
raymo

[Camelopardalis (Dunk)]

Thanks raymo, oops I forgot to put the ISO...1600

[jsmoraes (Jorge)]

if you work with Photoshop, to realce the nebula you can use the filter minimum with blend mode luminosity and 20 % or 30 % of oppacity with background selected. This will reduce the presence of stars without loss of information from the Nebula.

[LightningNZ (Cam)]

I rather like that the stars are over-emphasized. I think it gives it more of a 'visual' appearance.
-Cam

[Camelopardalis (Dunk)]

Thanks chaps - I'm learning, experimenting with my processing workflow, so I'm open to any and all suggestions it's hard for me to grasp how things should look... natural colours and so on.

As an update to my previous comment about the spacer...I tried again last night with the spacer inline and got stretching (like warp drive) effect on stars from about 2/3 the way out getting worse towards the edge. I took some shots of the same scene as above for comparison, and I don't see that effect on my shots from SPSP...so I can only assume that without the spacer is closer to optimal

[Regulus (Trevor)]

Seriously like the colours in that version Dunk.

Can we ever have enough of it?

Can't believe u even asked: Nope!

[Camelopardalis (Dunk)]

Thanks Trevor! It'll be interesting to see what happens to the colours when I can get my paws on more subs

I'm more of a visual guy but have a good look at it every chance I can!

[Camelopardalis (Dunk)]

So...I've been playing around with different stacking and processing parameters and ended up with a...erm...different result.

I don't think I like it as much as the first, it's more yellowy-greeny and the stars are more pronounced than before

What colours should I be aiming for? I appreciate there's a limit to the data I have.

[cometcatcher (Kevin)]

Originally Posted by Camelopardalis

What colours should I be aiming for? I appreciate there's a limit to the data I have.

Blues and reds. Unless they're comets, greens are usually not a sought after colour in astro pics, hence HLVG.

[Camelopardalis (Dunk)]

I've just tried recreating the first image from the same settings and the only difference seems to be the source images...the first was direct from the raw files, the second from raw converted to tiff files in Canon DPP

[Camelopardalis (Dunk)]

Originally Posted by cometcatcher

Blues and reds. Unless they're comets, greens are usually not a sought after colour in astro pics, hence HLVG.

Thanks Kevin, I'll stick with my first pic then as that's got less green to it. Not sure what's going on with the tiff conversion. Weird.