lalou

23 minutes ago, sharkmelley said:

No, don't raw convert them first.  But white balancing should be one of the first operations you do after stacking - while the data are still linear.

Thanks for this reco! I'll try this out. I guess I adjusted the curves already before I did the white balancing. 

1 hour ago, Elp said:

Curves will give you more control on width of peak, or use selective colour.

This worked wonders!! Thanks for this suggestion. I believe this is better since I think this doesn't clip out the data but just lessens it compared to adjusting it via Levels

1 hour ago, sharkmelley said:

Those histograms do not look like the histograms of linear data.  White balancing cannot be performed on non-linear data.  It raises the question about what kind of workflow you are following.  For instance, are you raw-converting your images before stacking or do you put your raw files directly into DSS?

I don't raw convert my images before stacking and I just put the raw files directly into DSS. Should I raw convert them first?

11 minutes ago, Rallemikken said:

I've imaged with modified Canon's for several years. Firstly I'd suggest you try out Siril, and it's "Photometric color calibration" tool. If that fails, use the standard color calibration tool. This will most likely give you a neutral background. For fine-tuning I use the "levels"-tool in my image manipulation software (Gimp). Choose the channel you want to reduce or increase, and move the middle slider a little bit sideways. Easy does it.

I'll check out Siril. So far I'm only using DSS and Photoshop. For the levels, when you're choosing a specific channel do you clip the data if its more than the other colors? I.e. for my case should I clip the red data in the levels just to have them equal?

4 hours ago, Elp said:

What does the histogram look like? You can also use an auto colour calibration in most astro software, Siril is free.

Here are the histograms for  each photo. I'm thinking that the red hue/tint is because of the wider field of reds in the image. Not sure if I should clip it to get the original color of the target. 

Any tips on how I can balance the colors on my images from my astromodified Canon350d? I already tried balancing the colors on the histogram when I edited these photos but I still can't remove the reddish tint (specially for the Omega Centauri). 

It has been 1 year since I posted this topic thread and I only found out now what was causing the dark streaks. I disassembled my camera and I noticed that the dark streaks was actually inside the sensor itself and not in front of the sensor or inside the telescope. Just had to wipe it clean and voila no more streaks. Thanks to everyone that helped! See images below fyr.

I tried imaging M101 here in our Bortle 5 neighborhood and it was sort of tough due to the light pollution but I think I was able to pull off a bit of data. My problem now is that I was able to increase the visibility of the galaxy through stretching but in the process the background noise also increased. I also noticed that my galaxy and stars are a bit orange/reddish compared to the other M101 shots which are kinda bluish in color. Not sure if this is being caused by my astromodded camera but I tried correcting it via Photoshop and this is the best "white balanced" image that I got.

Looking for some help in this group maybe someone can have a go with my raw file and share some techniques on how to improve my post processing. The stacking was done via DSS and the processing via Photoshop. I also used Gradient Xterminator and also Astrotools.

Here's my edit and I also attached the raw file so maybe you guys can try tinkering with it also. Also open for any suggestions or comments with my initial edit. Thanks! 😁

• Light Frames: 189 x 1 min shots @ ISO1600 (yes I still don't have autoguiding)
• Dark Frames: 198 x 1 min shots
• Mount: Celestron OmniXLT CG-4
• Telescope: Celestron C6N
• Camera: Canon EOS Rebel XT Hap-Griffin Mod

Autosave.tif

Autosave.tif

Hi! I've recently acquired a new Astromodified Canon rebel XT and I've tried to take pictures of nebulas using it but I've noticed that there are these weird black artifacts that keep appearing in my images. Would like to know if anyone has experienced this before? Or are these dirt/dust specs on the camera, filter, and telescope glass? I've attached some of my edited and raw pictures for your reference. The black artifacts can already be seen in the raw image of the horsehead nebula and after stacking I think it got amplified. Anyway, advance thanks and I hope everyone's doing well.

Wow! These are amazing images! This inspires me to keep on trying shots. I've always thought that you can't get decent photos using EQ3 mounts.