Cygnus at 50mm

[Adrena1in]

After a seeing a few Milky Way and North America Nebula images yesterday I decided to forget the scopes and just do a bit of camera+lens imaging last night.

Started off with a few 18mm shots of the Milky Way, 60s per shot, but these didn't turn out as well as I'd hoped. (Got Deep Sky Stacker to stack five images and three darks, but didn't get good results. DSS counted 16,000 stars per image. I'll try the RAWs later.)

Then I tried some 200mm shots towards the NA Nebula, and I'll process them properly in a bit, but got major vignetting. (DSS counted 9,700 stars.) Pointed towards Jupiter for a few shots at 200mm. (Oh yeah, while shooting the NA Neb at 200mm I saw a spectacular meteor going south to north. Quite slow moving really, lasted nearly two seconds I would say, changed colour several times and just missed my frame. Beautiful!)

Best result for me was a single 120s exposure towards Cygnus, with my nifty fifty at f/2.8 and using my Astronomik CLS filter. I had the aperture wide open the last time I tried this area and the result was poor. This is a lot better I think. Still some "smudging" of stars towards the edges though. (I did try stacking one image with a dark, but doubt it made any difference. DSS counted 31,234 stars though!! What's the most you've ever had DSS count?)

http://img291.imageshack.us/img291/8517/cygnus1x120s50mmsm.jpg

[Catanonia]

Very nice mate and good for a single exposure of 120 mins.

Can see some trails in there.

Try 1 min and stack more and more of them, you will be amazed.

Since you had image processing OK switched on, I couldn't resist.

Remember this is 5 mins processing with a JPG and not your RAW. Imagine what you could do with about 30mins of 1 min subs and processing.

http://extraview.dnsalias.com/temp/Adrena1in.jpg

The problems you are getting near the edge of the frames are vinegretting as the lense is not designed for this at affinity focus. This is why we use field flatteners on scopes.

Also try going 1 F Stop up on the nifty fifty, as the lowest is not always the best quality. Edit : Ah just reread your post and you are doing all this :)

The DSS count is not just stars mate, but noise as well at times.

Adding 1 dark will do nothing, infact make it worse. You need at least 5 darks to balance out and work out the average noise to remove from the images.


Keep them coming mate, this is a great start.

[heladepela]

VERY impressive results, but then I'm a noob in this area of photography so anything shiny is impressive to me :)
Do you still need a tracking tripod/mount to shoot these kind of shots ?

[Catanonia]

Do you still need a tracking tripod/mount to shoot these kind of shots ?

Not if you keep the focal length low and the exposure time short.

Ie this one was 50mm at 120 seconds.

[heladepela]

Cool, must try this the next time I'm somewhere suitably dark and without light pollution. I currently only have a 24-105 f4 and a 16-35 f2.8, is either of those usuable ?

And then you just stack shots using DSS ? Sorry for the noob questions, but these shots have really peaked my interest :)

[Catanonia]

Use your 16-35 at around 30mm and around F3 for 30 second exposures on a tripod with a shutter release and mirror lock up.

Take loads and stack them. Good luck.

[Adrena1in]

Nice edits there Cat, thanks. My image editing skills are terrible really, but here in the office I only have Google Picasa, so I just fiddle with the overall light and the highlights. What did you use to do your edits, and what exactly did you do?

As for RAWs, I've never had much success, but I'll upload one somewhere, (where?), if you want to show me what you can do with it?

And hela, you definitely need tracking to take a 2-minute exposure at 50mm. I've got a tracking mount, which is pretty good at wide angles really. There's no trailing in the image above...the streaky bits around the edges are due to the lens. (I think.)

[Catanonia]

I used PhotoShop and Noels Actions which is worth an additional $20

a. Balance the rgb channels using levels.
b. Lighten enough to get whole histigram
c. Use Noels to enhance DSO structure, brings out reds and other colours.
d. Re-level to adjust darks and lights.
e. Copy to new layer and add softlight and opacity to 40% to give nice contrast.


Pretty much it really, takes about 5 mins.

If you are serious about processing, you need to play with RAW as JPG contains loads of appromixations and compressions to reduce the size and ruins the data.

Cat




Nice edits there Cat, thanks. My image editing skills are terrible really, but here in the office I only have Google Picasa, so I just fiddle with the overall light and the highlights. What did you use to do your edits, and what exactly did you do?

As for RAWs, I've never had much success, but I'll upload one somewhere, (where?), if you want to show me what you can do with it?

And hela, you definitely need tracking to take a 2-minute exposure at 50mm. I've got a tracking mount, which is pretty good at wide angles really. There's no trailing in the image above...the streaky bits around the edges are due to the lens. (I think.)

[Adrena1in]

Got Adobe PS at home and Noel's Tools. Havent' used it for months and months.

Never got anywhere with RAWs either. Obviously always doing something wrong, because they were always so dark that whenever I tried to bring things out a bit it just made the image look terribly noisy and dirty. So I gave up.

[Adrena1in]

And then you just stack shots using DSS ? Sorry for the noob questions, but these shots have really peaked my interest :)

Yes, use DSS. It's really easy. At 16mm you should be able to shoot for 30s or so without too much noticeable trailing. Take 20 or 30 images, load up DSS, select your 20 or 30 images as Light Frames and click Stack. It's suggest some settings to go with.

Between the first and last images there'll be a lot of movement and some twisting, but DSS can handle that. You'll get a weird frame around the end of the final image, and in DSS it might look very bright and grey, but don't worry...just save it (have to save it as a TIFF I think) and then load it into PS or something to adjust the contrast and colours and stuff. You should be able to get a semi-decent Milky Way shot.

[adsayer]

noob question alert... but this is fascinating!

what is DSS? searches don't really provide any indication as to what it is? :(

thanks!

ads

[adsayer]

whoops after than I found it! :D

deepskystacker...

[Adrena1in]

what is DSS? searches don't really provide any indication as to what it is? :(

Stands for "Deep Sky Stacker". Free download, specifically for stacking multiple space images to produce a (hopefully) superior final image. ;)

[MintMark]

I use deep sky stacker with raw files and it does a great job. You can see faint features in the stacked image that are lost in the noise of the individual frames.

The resulting image does need stretching afterwards and the colours are usually different compared to digital photo professional, but it's so easy to use.