First LRGB Image

[Colorado CJ]

Last night I set up the scope to try out my first LRGB image. I decided on Bodes Nebula since it was pretty high in the sky. I set all the settings in APT to shoot through the filters and then slept until the images were finished, then shot 5 dark frames for each setting.

I can see all ready that I will need to focus for each filter in the future as the focus wasn't correct for blue and green filters, even though they are pretty expensive (parafocal) filters. The FWHM for the red filter was around 2.5-3 and for the blue was all the way up to 10.5-11.

I can also see that my field flattener isn't at the optimal back focus. I am going to have to find a way to fix that.

Anyway, I decided to go ahead and edit the image to see how it turned out. There are a lot of things to fix, as I stated above, and I should have shot more lights and more darks, but this is how it turned out. 20 Lum at 120 seconds and 111 Gain and 20 R, G, B, at 180 seconds at 111 Gain.

 

[Ben Egbert]

Wow, if this is flawed, you could not prove it by me.

 

[JimFox]

Wow, if this is flawed, you could not prove it by me.

Andrew, I will second Ben’s comment that if this is flawed, you sure have fooled me. I guess that’s the difference with Ben and I not really knowing what you are doing and you clearly knowing what you are doing.

 

[JimFox]

Congrats on the Daily Featured Post Andrew!

@Colorado CJ

 

[Jim Dockery]

This web image looks great. I'd imagine you see the flaws at higher magnification.

 

[Mike Lewis]

Andrew,

A very nice rendition. As always, things improve with more data, more dark frames, etc. but this looks good. The different focus through different color filters can be an issue, although if advertised as parfocal should not be a large issue. Do you take your sequences changing your filter between each subframe, or do you take your desired subframes with one filter before going on to the next type of filter? if you use the 2nd approach, your focus issue could just be focus shift over temperature as the night wore on, instead of an issue with focus shifting between filters used one after the other. of course, swapping to the next filter for each subframe has the added bonus that you usually end up with enough data to make some sort of an image if you get interrupted before the full data collect is completed, instead of getting all your LRG but then the clouds roll in before you can take any of your blue frames, just as one example.

Most astro collection software also has provisions for filter focus offsets for each filter, but of course to use that unattended you need to have some sort of an autofocuser present. That is something I hope to add to my setup this year at some point.

ML

 

[Colorado CJ]

Sorry guys, for some reason the displayed image is small. Here's a link to the full size image (click photo)

 

[Kyle Jones]

Very cool - especially since things will only get better from here!

 

[Kurt Harrigan]

Interesting image! Is it possible to make a chromatic aberrations adjustment and remove some of the yellows/cyans from the larger stars? The smaller red stars look kind of cool.

 

[AlanLichty]

Wow - glad I was late to the party so I could see the full sized link. Seriously cool image and the idea that what we see you make is going to get even better is tantalizing

 

[Dean]

Always love seeing these Astro images..so much effort and energy goes into making them and the output is incredible or should I say outer worldly Really beautiful!
Regards , Dean

 

[Colorado CJ]

I reworked the data to improve the image. The last one looks like garbage by comparison. I still need to shoot some flats to get rid of the ring in the center and some of the noise.

Here it is:

 

[JimFox]

This sure is looking good Andrew!

Did you get your dome finished? Are you set up shooting out of it now?

 

[AlanLichty]

This just keeps getting better.

 

[Colorado CJ]

Thanks everyone!

This sure is looking good Andrew!

Did you get your dome finished? Are you set up shooting out of it now?

Thanks Jim. No, I still don't have the dome finished. I am still working on the shutter area and shutter, then it needs to be fiberglassed. The shutter design had me stumped for a little while since I didn't know what type I wanted to build. I am going to basically split the dome in half with another two half circles of wood and make an "up and over" shutter that pushes up vertically.