MaximDL - First RBG image all blue?

[uptmor]

Hello all,

Well, I tried my hand at my first RGB image last night of M33. I'm using an Orion Parsec Mono camera and filter wheel. I took a simple set of images (2 each binned 2x2), followed the tutorial, and my image turned out all blue. I'm not talking it was heavy on the blue, I'm talking it looks like everything is the same shade of bright blue.

I'm not sure what I'm doing wrong here. I've looked everything over, and it looks correct. Anyone experience something similar or have some suggestions? Image attached (yikes).

Thank you in advance,

Ryan (Dead Rising Observatory)

[Spikey]

Can you attach the individual RGB frames you produced Ryan ?

[uptmor]

Hi Simon. Yes I can. I am at work right now and will do that when I return home. Thanks, Ryan

[Spikey]

Nice one, just post up jpg's of the individual stacked colour subs. I use Maxim to stack & calibrate the individual sets of subs but not for combining the RGB image, I taken care of that in Photoshop.

[uptmor]

I can't believe they pulled my little icon from playing Battlefield3.... It was funny there, not as much here

Yea, I just got MaximDL Pro, and the mono camera with filter wheel. I was doing DSLR pics before this, so this is a lot to bite off and chew. Maxim seemed to do really well with the stacking. I only took a few darks with no binning, so I was only able to calibrate the Lum. As expected (and I wasn't thinking about this), the sofware with not utilize those darks with the 2x2 bined color images.

Any reason you don't use Maxim to combining the RGB? Just curious. I'm trying to find a good starting process, as there is a lot to remeber and do through all of this as a beginner color filter wheel user. I'll post the images as .jpgs tonight. I'm assuming I just normalize the stretch before sending them? Thanks.

[Spikey]

You're right it is a very steep learning curve going from DSLR to mono CCD but well worth the effort. I just prefer to have more control over the combining in the different channels. The colour for my images might be captured over multiple nights which means dropping the frames into Registar to align. I don't bother with darks on the CCD it's not noisy enough, just BIAS and flats at the same bin as the lights.

I was going to drop your seperate RGB images into Photoshop and see if they combine OK, you can post the Lum up if you want as well. You can send them stretched if you want, they might come out a bit better as theres only so much you can do with a jpg.

[uptmor]

Well Simon, I'm pretty sure I figured it out. When I brought up all the L,R,G,B stacks and 'Equalize Screen Stretch'ed them, the blue image came out the brightest by quite a bit, and the Lum came out the most dim (by quite a bit). Obviously, this should not make sense.. So I organized the images from brightest to most dim and figured it should be Lum, Blue, Red, Green. This turned out to be perfectly one rotation off of my filter wheel. So, when I stacked the RGB using the FITs data, it came up VERY blue (due to it using the lum data for blue). If I stack them how I see correct, I actually get some result that looks correct, although dim and cruddy due to only taking 2x8 min lum. I'm attaching the result. I'm noticing a pretty extreme vignette, but that can be fixed...Still a 'reddish/blue' to some of the stars and center of galaxy..

[steppenwolf]

I'm tempted to think that you are on the right track now but that you still have the blue and green channels swapped over - try re-arranging the composite with blue and green swapped.

The vignette is pretty strong but taking flats for each filter will make a huge difference.

[steppenwolf]

Here is a down and dirty I did by separating out your channels, re-arranging them and dealing with the vignette a little using your JPEG.

[uptmor]

Thanks Steve! I'll take a closer look at the filters and the position settings. How did you work the vignette out? You did a pretty good job with a pretty rough image.

Thanks again for the help. Hey, if it were easy, it wouldn't as much fun

[steppenwolf]

My pleasure - Gradient Xterminator is your friend if you really, really need to fix a gradient although it does have its limitations.

[ollypenrice]

Well done Steve. Even more powerful than Gradient Xterminator, in my view, is DBE in Pixinsight but you have to buy PI for that. However, DBE is also the best automatic colour calibration tool I've come across as well.

Olly