Failing Miserably!

[Herzy]

I stacked 21 x 30s of M42, no darks or flats.. I see virtually no noise in the final stacked photo, so this means I should be able to stretch the data to get some nice detail... right? Well when I bring the image into nebulosity the histogram peaks in the middle, rather then the left side as I see in most tutorials. Why is this? It seems no matter how hard I try (I've been trying for the past 3 hours) I can't get a good photo. I simply don't know what I'm doing.

The best results I could get was using the digital development tool, and it still was not much better then the original photo. Help please!

-Hayden

Edited April 25, 2016 by Herzy

[wxsatuser]

Can you post what you have got?

[Joel Shepherd]

Yep, please post what you have. Also, Nebulosity's display by default auto-stretches images. It doesn't always get it right. Make sure the auto-stretch is disabled before working with the image.

[Herzy]

I tried to post it, but the file is too big. Tomorrow morning I will post it elsewhere and link it.

[Herzy]

 

Here is the stacked image. I know it's a lot to ask but if anyone has some spare time can you process this for me? I feel like something is wrong with my image because I can't process it.

Edited April 23, 2016 by Herzy

[Scott]

@Herzy

You'll be needing to post a link to the untouched stack as the image you have posted is quite small (file size not image size)

Dropbox is a good way to share large files

 

[Herzy]

Thats it. Thats straight from stacking and I posted to flickr.

[Scott]

Hmm, don't know what to say, when I downloaded it from flickr at origional size, it was only 304Kb. my stacks from dslr are 69Mb.

[Herzy]

Im uploading on dropbox but the file size 117MB. 

[Scott]

Just now, Herzy said:

Im uploading on dropbox but the file size 117MB. 

Thats much better . Post a link to dropbox when its downloaded   

[Herzy]

https://www.dropbox.com/home/Stacks?preview=M42-Stack.tiff there you go!

[Scott]

Sorry Hayden but I cant see it. To share an individual image I usually open where thefile is and on the right click share and then copy and pste the link that  comes up

[Herzy]

Can you explain more Im confused. It says its uploaded and when I click the link I can see it. :/

Never mind this might work.

https://www.dropbox.com/s/rf72fnt2pto6a4r/M42-Stack.tiff?dl=0

Edited April 23, 2016 by Herzy

[Owmuchonomy]

I had a quick play with it.  The blue channel is shifted quite substantially so bringing the colour balance back shows up the lack of flats and darks.  There is a lot of vignetting and some dust bunnies so I would urge you to apply flats before trying to process it.  Did you apply any histogram or colour adjustment during stacking?  Its best not to.

[Herzy]

No I didn't I simply stacked them. So I took all of those for no reason?  You can't bring out detail?

[Scott]

22 minutes ago, Herzy said:

No I didn't I simply stacked them. So I took all of those for no reason?  You can't bring out detail?

Downloading now so I'll have a play after  I feed my face

 

[Owmuchonomy]

What camera are you using? If a DSLR did you take your lights in RAW.

[Herzy]

I am using a Nikon D3200. Are calibration frames necessary? I know they are helpful, but couldn't I still get a good image from all of those pictures? 

Last night I took 60 x 30 seconds of M81 & M82 (still no calibration frames). I'll see how that goes.

[Herzy]

Which one?

[Joel Shepherd]

You want NEF raw. JPEG compresses and loses data. I'll play with your stacked image later (and give my self a break from my RGB frustrations :-). It looks like you should be able to get something out of that.

AP is hard and if you aren't regularly frustrated by it, you're not learning. It's just all part of the fun.

[Owmuchonomy]

Nikon's own RAW format is NEF I believe.  As long as your stacker such as DSS will read NEF files then that is the one you should be using. So pick NEF(RAW).  Yes, calibration frames will help immensely.  You have a lot of vignetting in your image so take flat frames to use and counteract this when you stack.

[Scott]

I'd just take raws. no need for jpgs as well. Flats are really important as you can see in my pic there is loads of gradient. Its not too late to take flats, as long as you get the camera/scope set upthe same as it was. Raws make a huge difference. what iso setting were you using? Try for 800 if possible and if you have the option for a histogram on the camera, keep it 1/3 from the left. anyway, here it is

[Herzy]

I took everything down and my camera screws in so theres no way I can get it aligned perfectly again. Oh well, practice makes perfect! Great job processing, mind if I steal that? It looks clear today so Ill get as much data as I can (including calibration frames). Thanks everyone!

Edited April 23, 2016 by Herzy

[Scott]

27 minutes ago, Herzy said:

I took everything down and my camera screws in so theres no way I can get it aligned perfectly again. Oh well, practice makes perfect! Great job processing, mind if I steal that? It looks clear today so Ill get as much data as I can (including calibration frames). Thanks everyone!

Mate,  you did all the hard work, it's yours to do what you want with. It's all about learning from our mistakes... If it were easy, visual guys would be doing it 

[Marky1973]

Hi Herzy, I had a fiddle as well and over-stretched it a bit as well as clipped it, just to show you there is plenty of data in there (and I am an amateur) - you really need to get some calibration frames in there though - DARKS/FLATS and LIGHTS will help you - there are a couple of "dust bunnies" that will benefit from FLATS. You will also need to start upping the length of exposure (and more of them) to get more detail, but there is a lot in there for just 30 second exposures - get some calibration frames in there and you should be able to start getting some nice images. (Thanks for posting the image, I'm still learning, so nice to have a play!)