does my M42 look too red?

[Pete Presland]

i have been playing with this for a while, its only an hour of data and i wish i had taken a shorter sub for the core.fairly pleased with the look of my first modded DSLR image, if a little shocked by just how red it looks.

canon 350d (modded) 20x180 secs, 6 darks, 6 flats stacked in DSS, tweaked inCS2

all comments very welcome! converting it to JPEG has not done it any favours

[stargazerslivingroom]

Now I'm definitely no expert as I've just started AP and can't even get focus but you did ask for comments....I absolutely LOVE the red...I can see a charging wild boar but (Sorry) can you tone down the white? It seems to be masking inner detail.

Remember what I wrote at the start!

Well done

Steve

[Pete Presland]

Now I'm definitely no expert as I've just started AP and can't even get focus but you did ask for comments....I absolutely LOVE the red...I can see a charging wild boar but (Sorry) can you tone down the white? It seems to be masking inner detail.

Remember what I wrote at the start!

Well done

Steve

i wish i had taken a shorter sub for the core, i have toned down the white on another image, i have been playing with it a while

[mart rich]

Beautiful detail outside the core area. I too LOVE the red. But I can see why you might think it is quite full on.

I am comparing it to my (very recent) first M42 (unmodded DSLR)

What did you process with out of interest? - I am just getting to grips with Nebulosity

Martin

[mart rich]

What did you process with out of interest? - I am just getting to grips with Nebulosity

Obviously I have now seen your reference to CS2....

Apologies

Martin

[Pete Presland]

until the recent photoshop cs2 freebie i have been using GIMP, this is the first image i have processed using photoshop cs2

[Pete Presland]

What did you process with out of interest? - I am just getting to grips with Nebulosity

Obviously I have now seen your reference to CS2....

Apologies

Martin

you posted that while i was typing

[earth titan]

Looks good. Nice image.

I find the modded cameras give lots more red than unmodded ones. Perhaps fiddle with the colour balance to drop it back a bit.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[Gina]

Nice start

[stem1989]

I think your core is over exposed, you would be better taking a series of 30 secs for the core detail and blending it in.

With you modified camera, the colours are always going to 'redder' than the purple hue that you see very often with unmodified cameras on this target. But I would suggest taking the saturation down a tad.

A great start and keep posting.

[Gina]

The colour is mostly a matter of personal taste and personally I like it When you get a bit more experienced, particularly with processing. you could take some short exposures that don't saturate the core and blend the stack of those with the stack you already have. M42 has an enormous brightness range and needs special treatment - it may be nice and bright but it's a difficult object to image. I have spent ages on this one and still not happy with what I've got - but that's normal enough, most astrophotographers are never satisfied As I said before I think your M42 image was an excellent start and I congratulate you

[Shibby]

That's nice - good detail and star shapes! You will need to restore the colour balance with a modded DSLR as the colour correction filter is no longer present. The easiest way (and what I do) is to enable RGB background calibration in DSS when stacking your images together. Give it a go!

Also might be worth mentioning that 6 darks isn't really enough and you might be better off without them.

[Pete Presland]

That's nice - good detail and star shapes! You will need to restore the colour balance with a modded DSLR as the colour correction filter is no longer present. The easiest way (and what I do) is to enable RGB background calibration in DSS when stacking your images together. Give it a go!

Also might be worth mentioning that 6 darks isn't really enough and you might be better off without them.

not heard of the "enable RGB background calibration" in DSS when stacking your images together. i will Giving that a go. surely the darks are a must for the hot pixels, or will DSS sort them as well?

[Gina]

You will need to restore the colour balance with a modded DSLR as the colour correction filter is no longer present.

Not for astro imaging you don't!

[cosmojaydee]

I find that no matter what comments you get , yes you may get help or advice on how to improve this , how to improve that , but if you are happy with the image that's all that matters, personally I love it , and I don't mind an over exposed core, the core has 4 stars its supposed to be bright ,to me it looks more natural than a core that has been toned down to much

so two thumbs up from me

[Gina]

I find that no matter what comments you get , yes you may get help or advice on how to improve this , how to improve that , but if you are happy with the image that's all that matters, personally I love it , and I don't mind an over exposed core, the core has 4 stars its supposed to be bright ,to me it looks more natural than a core that has been toned down to much

so two thumbs up from me

I agree with that. I don't like the core flattened too much either.

[Shibby]

Not for astro imaging you don't!

Sure, you don't have to do anything at all but if you're gonna balance the colour in a daytime image, why not do it in an astro image too? It'll reveal the wonderful colour variations between emission (red) and reflection (blue) nebulosity that pervade M42. This is not to take anything away from the image, which is already fantastic. But bunnygod did ask for advice and specifically on colour balance.

Actually, looking at your image bunny, I'm guessing (and I might be wrong) that you've already taken steps to balance the background but you may have done this after stretching the levels (or, at least, just to the background and not rest of the image?)

With regard to hot pixels, yeah stacking can eliminate them with enough subs and if sigma clipping is used. 20 might juust be enough - not sure... Darks can actually add extra random noise to your final image if you have too few of them; I have a library of dark masters that I can use for any image by matching temperatures.

[Uranium235]

That almost looks exactly like my M42 when it first came out of DSS. It needs to be rebalanced, I found it easier just to split the RGB master into separate components, then recombine with the ratio Red = 0.9, Green = 1.00, Blue = 1.25. That will get you closer to a more agreeable colour, but you will probably need to do some additional tweaking with the levels function.

Take your time with this one, its harder than it first looks

[JKB]

Well this looks very similar to my first M42 after modding the 30D

I reset the white balance (google how to do it) then retried. Next image was a lot better. After putting through DSS I aligned the three curves R G and B so they were on top of each other and put the Saturation up to about 20%. Then saved with adjustments.

Quick tweak with PS and done. Yes the core is over exposed but you know that as others have said but still a good image so well done. This is what I got from the instructions just given with a modded EOS 30D through 150P. 20x3min exposures plus around 30x90s and 30x15s (plus a few darks and bias) I used the blending technique here http://www.astropix....GIT/LAYMASK.HTM to combine the core with the rest.

Hope that helps?

Cheers

Jamie

[Pete Presland]

thanks for all the advice, i will certainly be re-trying this.i have a play with the image but not re-stacking which will try. resetting the white balance looks like a must looking at JKB's image, so i will try that i think as well.i am quite pleased with the amount of red, but does seem a bit "biased" to the red channel

[earth titan]

i am quite pleased with the amount of red, but does seem a bit "biased" to the red channel

My shots of Orion before the camera was modded are purpleish and with modded DSLR, they are RED. Nothing wrong with that though.

Typed by me on my fone, using fumms... Excuse eny speling errurs.

[ollypenrice]

Not for astro imaging you don't!

I don't agree, though I'm really a CCD imager of course. All the modded DSLR images I've seen, and the few I've been sent to work on, have been overly red straight from the stack. I feel that this image is typical of the breed. Whether or not one likes the colour is personal but it wouldn't be that colour in an accurate colour calibration. There's a fair amount of blue reflection contributing to M42.

I use Pixinsight to colour calibrate, these days, but a good Ps rule of thumb is to have the top left of the histo peak aligned in each colour channel. Here's the histogram from a quick screen grab of the OP's image.

The fact that the red is far fuller may arise from the object itself or from the camera collecting more red. You can't tell just from the hisogram, though I'm sure it does collect more red. What you can tell, though, is that the colours are misaligned. Poor old blue is almost black clipped (careful to take nothing whatever off that black point!) while red is well over to the right and needs clipping back. Green too, but watch out for the magentas getting too strong if you take off too much. (I think Jamie's green balance needs a tweak, myself.)

It's a nice image, very nice indeed, in other respects and I'm sure it can be sorted. Personally I'd shoot core subs well shy of 30 seconds, though. Maybe half that? I used 11 seconds in CCD at F5.3.

Olly