The elephant trunk nebula. A lot of photoshop youtube tutorials later

[5haan_A]

Hi Guys,

 

I'm happy to share this one. After all the bad weather it was nice to get the rig set up and get some imaging done. I hadn't had a much of a chance to practice and improve since making some early headway around September time, so I was really excited when I saw that the weather was looking clear on the 25th/25th March. On earlier attempts polar alignment, short exposure time, and not enough data had meant that most of what I had done so far wasn't what I was hoping it could be. Which is fine, because there's been a lot to learn, there's that cliche about journeys and destinations that holds true for my own experience for sure. 

 

Of those things to learn, I have found the area of processing a little bit daunting, relying on the quick and easy solutions out there like a bit of DDP in Nebulosity and that's that. I had thought about photoshop but took one look and thought 'I'll come back to that one'.  So I came back to it for this image. I downloaded a free trial of Photoshop, watched a lot of videos and got to work.  I was blown away by just how much finesse you can have with a powerful bit of software. Hopefully over the next few months I can learn a bit more about PS and start putting that power to good use. 

 

For this image I took:

40x180 sec and 40x240 sec lights at -10celcius

49x240 sec dark frames 

Flats

 

The setup I use is:

Esprit 100 ED Scope 

ZWO 294 OSC cooled camera

EQ6 R Pro mount

 

Feedback is most welcome, I felt I struggled the whole way getting the colour true, and definitely struggled with noise reduction.

 

 

[MarkAR]

Not too bad, I think if you cooled your camera down further you would have lost some noise.

I like the colour tone, more orange gold than red makes it seem more natural.

[5haan_A]

9 hours ago, MarkAR said:

Not too bad, I think if you cooled your camera down further you would have lost some noise.

I like the colour tone, more orange gold than red makes it seem more natural.

What temperature do you think would be better? 

Re the colour tone thanks. It's just the way it came out in the end. I had a black and white reference point and all I did was make black black and white white.

A quick question for anyone that can help. When capturing this I used lights of 180 seconds and 240 seconds. Essentially I did 180 on the first night and 240 on the second night. The reason was because after a cursory check on the 180 second exposures I thought I could get more with longer. Now when I stacked the image I stacked all in one go. Does stacking them all together as one diminish the 240 second exposures, or does is it not matter?

 

Edited April 6, 2020 by 5haan_A
Typo

[MarkAR]

21 minutes ago, 5haan_A said:

What temperature do you think would be better? 

I would aim for -30º if possible. Might take a while with the warmer weather but see how it goes and if it seems to plateau out at say -27º then dial it back to -25º.

[Notty]

4 hours ago, 5haan_A said:

A quick question for anyone that can help. When capturing this I used lights of 180 seconds and 240 seconds. Essentially I did 180 on the first night and 240 on the second night. The reason was because after a cursory check on the 180 second exposures I thought I could get more with longer. Now when I stacked the image I stacked all in one go. Does stacking them all together as one diminish the 240 second exposures, or does is it not matter?

 

Stacking them together shouldn't be a problem as long as you stack them with their own calibration frames. Sorry if I'm teaching you to suck eggs but just in case you can use the groups tabs in DSS? Eg front group would have you reference frame (for alignment) and any common calibration frames (which I don't think would apply in this case unless focus and orientation was identical on both nights in which case you could use a common flat, and if it were multiple nights at the same exposure and camera temp you could use a common master dark) then groups 1-n would be each night's lights and unique calibs. 

That is a cracking image by the way!

[5haan_A]

23 hours ago, Notty said:

Stacking them together shouldn't be a problem as long as you stack them with their own calibration frames. Sorry if I'm teaching you to suck eggs but just in case you can use the groups tabs in DSS? Eg front group would have you reference frame (for alignment) and any common calibration frames (which I don't think would apply in this case unless focus and orientation was identical on both nights in which case you could use a common flat, and if it were multiple nights at the same exposure and camera temp you could use a common master dark) then groups 1-n would be each night's lights and unique calibs. 

That is a cracking image by the way!

Thanks. 

 

I hadn't actually done the above mentioned when I was calibrating so I appreciate that. 

Best,