Jump to content


Photo

Is M33 Really in there? :)

  • Please log in to reply
6 replies to this topic

#1 ddanley

ddanley

    Explorer 1

  • -----
  • Posts: 77
  • Joined: 08 Aug 2013
  • Loc: Friendswood Tx

Posted 06 October 2013 - 04:34 PM

So... I purchased the Orion SS autoguider and used it last night to capture M33 from my light polluted back yard... I too about 20 240 second lights and stacked them with DSS...

I used levels and curves in PS but keep on starting over. I can see hints of the galaxy, but can't seem to bring it out. I would LOVE to see what it would look like from someone who knows how to extract the data!

Here is the 32bit Tif from DSS if anyone wants to show me :)

http://danndanley.com/M33.tif

#2 Phil Hosey

Phil Hosey

    Surveyor 1

  • *****
  • Posts: 1634
  • Joined: 29 Oct 2008
  • Loc: LaGrange, GA

Posted 06 October 2013 - 05:49 PM

Looks like you have some pretty severe vignetting and the object is off-center. I just did an initial histogram stretch, converted to .JPG and reduced it so I could post it. I'll crop the vignetting out and see if I can do anything with the galaxy.

Attached Files



#3 Madratter

Madratter

    Fly Me to the Moon

  • *****
  • Posts: 7135
  • Joined: 14 Jan 2013

Posted 06 October 2013 - 06:41 PM

The potential is there. Some problems with this image are:
1) Not centered.
2) Vignetting - you didn't specify telescope and camera so not sure what can be done here.
3) The need for calibration frames (darks, flats, etc.)

Attached Files



#4 timtrice

timtrice

    Viking 1

  • -----
  • Posts: 643
  • Joined: 01 Aug 2013
  • Loc: Katy, TX

Posted 06 October 2013 - 06:47 PM

Dann! Good to see some stuff from you again!

I messed w/ it a bit too after doing some cropping, DBE (which didn't remove much other than the vignetting), stretch and bit of curves. Got pretty much the same.

Dann, what sky map are you using? Before I start my imaging, I use the live view if I have stars visible and identify where I'm at the center. If I don't have any stars visible, I just try to take as short exposure as possible with the ISO cranked. This way I can assure I'm not cutting anything off that I don't have to.

I'm not sure it'd save you in this image, but something to keep in mind.

I know you're in a heavier LP zone than I am but all I can suggest to help would be to try and get that histogram between 1 and 2/3. I think you can probably go all the way up to half and capture the finer details while also being able to not completely overexpose. The LP can come out in processing.

Looks like your auto guider really is working out for you! Glad to see that (feels good, doesn't it :)). I don't think you need to toss this data. Maybe someone more experienced would disagree. But try to center it better and put a couple more hours worth of data on it. If you can do that I'd imagine you'll get much more pop out of it.

#5 CounterWeight

CounterWeight

    Cosmos

  • *****
  • Posts: 8237
  • Joined: 05 Oct 2008
  • Loc: Palo alto, CA.

Posted 07 October 2013 - 10:12 AM

I just want to put in my usual plug for taking flats being Critical to the calibration process and therefore Anything that comes after. Processing (stretching and gradient removal and the basic image balancing) and post processing (color balancing and contrast, making it pretty) all depend on a good calibrated sub exposure. Flats are Key to all of this. Flats are not convenient or even fun to learn to take - but they are extremely vital.

#6 ddanley

ddanley

    Explorer 1

  • -----
  • Posts: 77
  • Joined: 08 Aug 2013
  • Loc: Friendswood Tx

Posted 07 October 2013 - 05:24 PM

Thanks guys!

Tim... I used ISO 200 since I was taking 240 second exposures... I didnt even check the damn histogram in BYEOS! I am pretty happy with my first attempt at guiding... It wasn't perfect but is was very windy too! I may try again tonight since our fine members of congress have given me a vacation :)

Jim, Thanks for the input... I need to learn how to take flats... That is on my list of things to learn!

#7 timtrice

timtrice

    Viking 1

  • -----
  • Posts: 643
  • Joined: 01 Aug 2013
  • Loc: Katy, TX

Posted 07 October 2013 - 05:51 PM

Ha! Yes, I was wondering how you were doing with that but didn't know if it was a touchy subject for you or not. Surprised you didn't take the RV out of town.

Regarding flats, put your camera on AV and switch BYEOS to AV-Flat. If you don't have a light box yet just point it towards the sky during twilight. I've been doing that and had mixed results (bad results when I wait too late). I won't say it's perfect but I many people do and you can run them off while you're setting up. Doesn't take too long.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics