Eagle Nebula

[RyanJones]

Hi All,

My first attempt at the eagle Nebula for the year. Mainly used as more learning time with the STC Duo Filter.

I resisted the temptation to go for a high ISO to really test my theory that my camera has better dynamic range at ISO 400 rather than 800 and I think I’m right. The colours in my recent images have been quite washed out where as I found it easier to get saturation with this one.

I’m not super happy with this image. The last time I imaged it it was with my C5 and I think this object responds better visually with the longer focal length. I am hoping I can attempt it with my 9.25 at some point framed on the pillars which are somewhat lost in this wide field version.

36x600 sec @ ISO 400
Astromoddified Canon 350d
STC Duo Filter
Vixen R130sf
HEQ5 pro guided with Nextguide SAG
Bortle 8 skies

Thanks for looking

[casstony]

Looks good Ryan, the 10 minute exposures helped to capture more extensive nebulosity. I've only gone up to 7 minutes myself - have to give 10 a go. I suppose it's easier to do longer exposures with the filter since the bright stars won't blow out.

Common wisdom is that ISO 800 is best for the canon's.

I'm not familiar with narrowband images but I guess the lighter area is dominated by OIII.

My L-enhance filter arrived yesterday and we had a few hours of clear sky in the evening but I didn't get home until 11pm - too late to start setting up.

[Startrek (Martin)]

That’s a nice image Ryan , seeing conditions ultimately govern your resolution so don’t be to critical about your attempt there’s heaps of detail in there and colour is of course spectacular
Also the general consensus about ISO 800 being the sweet spot for Canons SNR is true but can differ especially with focal length , exposure time and whether your running a standard DSLR or Astro modded
Mine 600D is standard and ISO800 is definitely the best all round setting for my set up but everyone’s set up is different
Great work keep it up !

[raymo]

There is no general consensus Martin, each Canon model has its own sweet
spot where the two noises intersect on a graph; some are 800, some are 1000, and some are 1600, and so on.
raymo

[Startrek (Martin)]

Raymo,
Totally agree, each camera has its own parameters, efficiencies, deficiencies and performance levels at various exposure lengths, environmental conditions and so on....
I just used the term “general consensus” as a majority of literature you read on Astro forums , websites, technical journals and the like, mentions about Canon cameras and that “magical” ISO800 !
This is the case for my 600D and few others in regard to long exposure AP

Cheers

[RyanJones]

Thank you Martin and Tony, I really appreciate the feed back.

With regards to the camera settings, I’m purely referring to the dynamic range not the SNR. This particular camera seems to prefer a lower ISO to retain colours. At 800, my reds aren’t deep red but more of a pinky colour.

[ChrisV (Chris)]

Nice Ryan. Keep at it! I'm finding it's taking a while to get the hang of this filter.

And I find a lot can be done in the processing - split out the red and green, and work on them separately. Although I'm finding it a bit of a rabbit's warren.

[ChrisV (Chris)]

And I've ended up dropping exposure back down to 5-6min with this filter. I'm still swamping read noise by about 5x. But maybe you need to go higher with the DSLR?

[RyanJones]

Thank you Chris,

There’s no doubt it’s a fantastic filter but the processing is very different. I haven’t been processing the channels completely separately but I have found myself doing selective stretching of the blue and green channels after my initial global stretch I’m hoping to be able to pull back a little on the exposure time too now as I have just bought myself an 8” f/4 Newt. I’m finding that at this exposure length I’m getting amp glow in the corner of my sensor so I think I’ve found the limit of this particular camera.

P.s. - I’m sorry to anyone in Melbourne that was hoping for clear skies. The clouds are my fault this week.