I'm pretty happy with my progress so far. Things are going well. There's always challenges but I'm getting on top of them.
The problem I have is my reds. I'm barely getting any. I recently did 1 1/2 hrs on lagoon. As much as it came out as a beautiful image it's missing the big red cloud.
Determined to capture Eagle, I did 2 sessions totalling nearly 3hrs. I've got the core, I've got the pillars, but very little red nebulosity. It's there but it's just not that bright like every other colour.
Am I doing something wrong ? Is it a white balance thing ? Is it a setting in DSS that I'm missing ? ( my Bayer matrix is set on canon 5d ) or is it as I was first suspecting, light pollution washes out that end of the spectrum. If so, is there anything I can do to compensate ?
I will note that in the photoshop histogram the red section is clear, has the same rough amplitude and is aligned with the other channels.
Any suggestions are welcome before I start the trial and error method
What I found was to play with brightness and contrast ...it was at extremes but I found if its there it poped out. GIMP same ...I don't know why..it may not work for your stuff..
alex
Is your camera astro modded? An unmodded dslr is not very red sensitive, you have to do a lot of processing to tease the reds out.
Hi Rick,
No it isn't Astro modded so I know that isn't helping the situation but I'm sure I should be getting more than I am. Early on when I really had no clue what I was doing and when I had my 350d on my smaller scope, my photos were coming it too red. I'm not sure what I did to change it but I did start to get the better balance. Now I have the opposite problem.
I have my cameras white balance set at 6000K, however, looking at the data on one of my subs I noticed that the white balance was 4250K. I've just realised that my camera was on auto white balance, so it's been taking the photos still in a colder range. I have cloudy skies tonight so I can't test the theory, is it possible that this has caused my camera to be less red sensitive?
Hi Ryan, You are behind the 8 ball from the word go with either of the two scopes you have listed. Being so slow, they require long subs to image
DSOs which have their light spread over large areas, as opposed to bright objects such as planets and some planetary nebulae whose light is
concentrated in small areas. It won't matter how many subs you produce,
you still won't get to see much red[except in the few objects where the red is very bright such as M20] if the individual subs are not long enough. You don't
say how long your subs were.
As already stated, non modded DSLRs are not very sensitive to red, which
further exacerbates your situation. Just saw your reply, set your white balance to daylight.
If your previous images were too red, it is most likely that your colour balance was off.
raymo
Last edited by raymo; 09-09-2018 at 08:21 PM.
Reason: more text
Ryan, are you using RAW files or the JPG files from the camera?
If you are using the RAW files (which you should) the white balance should not matter. JPGs are compressed which will reduce the final quality and also have the white balance applied to them.
Ryan, are you using RAW files or the JPG files from the camera?
If you are using the RAW files (which you should) the white balance should not matter. JPGs are compressed which will reduce the final quality and also have the white balance applied to them.
Hi Luka,
I am using RAWs from the camera. So it can't be the white balance then.....thank you for clearing that one from the possibilities. Any suggestions ? Is there maybe a setting in DSS that I have ticked wrong and it's cancelling the Reds out ? As I said before, blues, cyan, magentas etc are no problem at all, they come out clear.
My canon’s get almost no red also. I read somewhere that they are basically designed to filter out the red hydrogen. I’m very new to this myself but I do recall reading something like that.
Can you post a few raws somewhere so I can have a play I can then work out a workthrough for you
That would be great thank you Nikolas. Given that they are about 12mb each, the only way I can think to ge hem to you is email. If it is ok with you, can you PM me your email address and I'll send some though when I get a chance.
My canon’s get almost no red also. I read somewhere that they are basically designed to filter out the red hydrogen. I’m very new to this myself but I do recall reading something like that.
My old canon 350d captured the Reds but maybe the far superior 5d has a far superior IR filter. I'll look into that some more. Thank you for your suggestion.
I actually imaged the same target last night with my unmodded Canon 600D - ISO1600 180sec @ f4.8. I have attached a single sub that has been debayered, rough colour correction and mild stretch.
I am personally happy with this result out of an unmodded camera, are your subs similar? https://www.astrobin.com/365983/0/?nc=user
definitely sound like the built in IR filter in your camera, chucking out too much red end of spectra. i know it doesnt and shouldn't matter but i set white balance to daylight and my jpegs give me good star colours without tinting. processing i use raws of course to process. do you have any other filters in the optical train? light pollution maybe? could be blocking some of the red end as well. What about other camera settings like noise reduction? long exposure noise reduction? scene modes? I donmt trust all cameras to not modify the raw data a bit based on other settings. I manually set everything I can and disable everything that does auto-anything at all. But still thinking the ir filter in that camera is stronger than other models you've used. You may have to look at spliting your integration frame into colour channels and create a lightness mask to apply a boost to your red channel (probably each) then recombine to colour. just like with regular photography you could adjust histogram levels for each channel to get a good overall exposure. you'll have to deal with noise perchannel as red will be swamped since you're retaining so little.
I actually imaged the same target last night with my unmodded Canon 600D - ISO1600 180sec @ f4.8. I have attached a single sub that has been debayered, rough colour correction and mild stretch.
I am personally happy with this result out of an unmodded camera, are your subs similar? https://www.astrobin.com/365983/0/?nc=user
Being that my scope is an f10 and my mount has monstrous PE limiting me to 25 sec subs. My subs are considerably darker and appear to contain very little.
This is my Lagoon. To be honest I think its a nice photo but I cant ignore the fact it has no reds. I wasn't game to post it before but seeing as you're all being so helpful...... please go easy....
definitely sound like the built in IR filter in your camera, chucking out too much red end of spectra. i know it doesnt and shouldn't matter but i set white balance to daylight and my jpegs give me good star colours without tinting. processing i use raws of course to process. do you have any other filters in the optical train? light pollution maybe? could be blocking some of the red end as well. What about other camera settings like noise reduction? long exposure noise reduction? scene modes? I donmt trust all cameras to not modify the raw data a bit based on other settings. I manually set everything I can and disable everything that does auto-anything at all. But still thinking the ir filter in that camera is stronger than other models you've used. You may have to look at spliting your integration frame into colour channels and create a lightness mask to apply a boost to your red channel (probably each) then recombine to colour. just like with regular photography you could adjust histogram levels for each channel to get a good overall exposure. you'll have to deal with noise perchannel as red will be swamped since you're retaining so little.
I'm really thinking its a combination of light pollution and the IR filter.
My setup is camera to scope with nothing else. I'm thinking that maybe I should work towards a focal reducer to increase the brightness of the objects. It was an idea I had a while ago and I just haven't done anything about it. Are UHC/LP filters worth it for photography ? As far as the camera goes, I have done the same, auto everything off. I shoot in Bulb and store in RAW. About as Raw as I think I can make it.
Ive seen plenty on here about shooting different channels and luminescence but I have no idea how to go about it ? I'm certainly interested to learn.
Going off what you said about f10 with 25sec subs I think that is going to be the main reason you are not seeing much red - there just isn't enough light getting in.
Like you mentioned I think a good investment would be a focal reducer, also an autoguider setup would be highly recommended.
Once your guiding is sorted out and you can get some 3-5min subs + a faster optical system I think you will start to get the colours you are chasing. That is where you are going to see the easiest wins and biggest gains.
Going off what you said about f10 with 25sec subs I think that is going to be the main reason you are not seeing much red - there just isn't enough light getting in.
Like you mentioned I think a good investment would be a focal reducer, also an autoguider setup would be highly recommended.
Once your guiding is sorted out and you can get some 3-5min subs + a faster optical system I think you will start to get the colours you are chasing. That is where you are going to see the easiest wins and biggest gains.
Thank you for the friendly advice David. Time to start saving the pennies I think
I'll look into that some more. Thank you for your suggestion.
