Horrible NGC55

[iceman]

Hi all

I took this on Sunday night from home, after spending considerable time drift aligning and getting the balance right.

I was able to get 2 minute exposures without trailing. Perhaps I could've gone longer but didn't try.

The sky wasn't very dark and there just isn't much dynamic range in the image. I took 15 subs @ 2 minutes each, and took 10 darks.

Saxon ED80 on EQ6, Canon 350D at prime focus. No guiding.

Focus wasn't spot on, either. Stars are slightly bloated.

1. Where's the colour? It's almost greyscale.
2. Using IP to subtract the darks ends up with black "spots" on the light grey background. ie: my avg'd darks seem to have white spots on them. I'll post an example later. Anyway so I have to use DSS which doesn't have this problem.
3. The second attachment shows the dynamic range problem? It shows up worsed when scaled down (50%). I left the background lighter to show it. What is this from?

Anyway I'm not very happy with it but I am continuing to learn so one day it'll all come together.

[[1ponders]]

The black spots may have indicated a temperature difference between the time you took youir lights and the time you took your darks. It may also depend on how your darks are combined and then subtracted from the lights. Do you combine your darks and then subtract from individual lights or do you subtract the dark after the lights have been combined. Also do you use median combine or average?

It's not unusual for galaxy shots to come out looking like a greyscale image. The IR filter in the camera does a pretty good job of filtering out the more subtle low end red colours.

[Garyh]

Good go at it Mike! If you can go longer Mike that wouldn`t hurt..maybe 4-5min if possible?
I usually have to add up too 15% saturation to get my stacked image to where I am happy with it (in deepskystacker).
there is color in there but very subtle..
Don`t know image plus but with DSS under stacking settings make sure you have auto detect hot pixels checked this might be those little white spots?
Don`t know why you have that bad dynamic range but? did you save as a 16bit tiff?
cheers Gary

[[1ponders]]

Good call Gary. I'd forgotten about that sneaky little catch. When I first installed DSS the default setting for saving TIFFs was 8 bit. :mad2:

[Dennis]

This irregular galaxy does have a low surface brightness so you’ve chosen a difficult target! However, you have captured it vey well, especially for 2 min subs with a DSLR. I also get black pixels with my SBIG ST7, even though it is temperature regulated. In CCDSoft (camera control software for the ST7) there is a “Remove cold pixels” function which can be set to Weak, Medium or Strong and this usually gets rid of these pesky critters.

Cheers

Dennis

[zipdrive]

that's pretty good for 2min subs.. definitely on the right track.

[PhotonCollector]

Actually I don't think the image is "horrible" as you describe it, Mike. Rather, I would describe this image as "a darn good start". We all start near the bottom of the ladder and we are all alike in that we wish to make our images look better. The next time you do a deep sky object, you'll refine your techniques based on what you have learnt this time, and produce a better image than this one! (when all things go well).

This is what I call the hobby of Astro-photography. Its fun and challenging, sometimes a little disappointing. If you produced a "perfect image" everytime there would be little challenge, I think that would make the hobby less attractive.

So keep up the good start and remember that your image does show NGC-55 well, along with that major dark dust lane and those bright starburst regions.

cheers
Paul

[davidpretorius]

well done planet boy!

[Alchemy]

i think Photon Collector said it well, the day i get the Perfect image will be the day i give up. Theres always something to learn and improve on...
Even the A league imagers would agree with that. Its nice to see everyone trying to improve their images no matter where youre at.

Cheers AL

[Lee]

I think it's a great image Mike - you are too hard on yourself.

[Ric]

Hi Mike, I have read that this is a toughy to image. I think you have done a fine job with this one.

Cheers

[iceman]

Thanks all for your feedback.. I know there's a huge learning curve and i'm just at the beginning.. I guess it's just the perfectionist in me trying to jump too far ahead of myself. I like learning but I like to be in more control, and I feel at the moment that there's too many things out of my control. I'll just have to work on them one at a time.

Deep space image processing is a whole new ballgame and I feel i'm just not doing this right, or as well as they could be. I'll need to seek the advice from some experts to get me on the right track.