Lagoon nebula

[thegableguy]

Shot this of M8 tonight. 20 x 2mins unguided, 10 darks, 10 flats.

I focused the scope as normal (by using Live View and zooming way way in) but the images turned out slightly unfocused. Like an idiot I didn't tighten RA properly before mount alignment, whoops - so it moved around a lot during the alignment process. Guess all that slewing threw it very slightly out of focus.

Anyway. Cautiously happy with the processing & editing - there's a fair bit more detail in there than any image I've yet done. Not sure if that's more to do with shooting at ISO 400 as opposed to 1600 or if I'm just getting better at the whole process. Either way, bummer about the focus but at least I feel like there's some progress being made. The fact I was able to drift align well enough for reasonably round stars at 2 mins is a small triumph.

[glend]

That's a nice start. There is a central coast casual star party coming up at the Pony Club on Saturday, see the thread in the star party section if your interested.

[Atmos]

It's still a pretty good image :)
Where running at ISO400 helps over ISO1600 is being able to process the light and dark areas. The higher the ISO the mor compressed the dynamic range becomes.

A lot of people image at ISO1600, stacking more images increases the dynamic range and if there are blown out areas you can always take some shorter exposures to bring them down.

[Somnium]

Nice one Chris, looks like you have sorted those polar alignment issues ! Great work

[thegableguy]

Would love to but I work every Saturday night for the foreseeable future! I imagine you're all long gone by 2am yeah?

[thegableguy]

Is there any more to the process than just taking a few lights and corresponding darks at a different ISO, and chucking them all in to be stacked together? Is there a certain setting in DSS that will lend itself to different exposures?

[thegableguy]

Thanks mate! Getting there. Last night I did two iterations of drift alignment - think it made all the difference. Just realised that when you change one, the other changes slightly too. Gotta go back and forth a little. It's a nice feeling when you get it right though.

Also used barbell weights, ie 5kg weightlifting discs, to put the tripod legs on on the grass. Finally found a use for them (I certainly don't use them for exercise!).

[Mickoid]

Chris, amazed at your 2mins unguided for this shot. Stars are pretty round, your PA must have been really good. Well dine. At 2 mins you should be getting more detail than your processed image shows. I downloaded your picture and did a quick edit on my phone using the picture editng software and came up with this.

[thegableguy]

Thanks! Yeah drift aligning was a major headache when I started a few weeks ago, but I seem to be getting the hang of it.

Agree that the editing of this one isn't the best. It was about 1am when I did it and after a particularly exhausting weekend I wasn't exactly at my best (several beers may have been consumed during data collection)... had another shot at editing now, attached, but I think it's more to do with how I'm using DSS than the editing. The final TIF always comes out way too high contrast (very very black sky) and no colour. TIFs are nice and rich in dynamic range but there's only so much you can do.

Also think ISO 400 was a little ambitious. I think one stop will possibly lead to some blown-out stars, but I'll make that sacrifice to get some more of the fainter nebulosity.

[Atmos]

Don't forget, you can always take some 15 second exposures to blend into the longer ones. If you blow out the brighter parts you can salvage it :)

[Edison]

Excellent shot! Great job! Congrats Chris.:thumbsup:
Regards,
Edison.