First processed image with a CCD

[Spookyer (Brett)]

Hi all. Here is my first processed image from my new ccd camera.

I have had it a couple of months learning the ropes and trying to get enough data around the clouds that have been a feature of the Brisbane weather since Xmas.

On the processing side certainly a big step up from the DSLR processing world. It has taken me most of the day to come up with this on the back of watching dozens of tutorials over the past two week and getting some tips on Pixinsight last week from Geoff and notes from RickS.

Image is composed of 15x20min Ha subs and 18x20min OIII subs so about 11hours worth all up. I think I managed to collect reasonable data, it is my processing skills that need to improve.

I wanted to get a bicolour type effect between the Ha and OIII but was unable to do so. I mapped the colours in PixelMath to something I think was okay just by trial and error. (still don't understand how this actually works) It looked okay stretched with the STF unlinked but when I linked the channels to stretch it the colours change quite a bit to very similar tones and just creates a one colour type image. I could do yellow, red or green but all basically the same tone in each image. Couldn't see how to get around that. I don't understand how that link/unlink channel concept works in theory.

Any comments are appreciated on the result.

Image details are on AstroBin with the image.

http://astrob.in/89863/0/

Cheers

[SimmoW (SIMON)]

Damn good first effort I reckon.

I'm pretty sure you don't need to use pixelmath to nominate the channels. I'll let the experts chime in though, I've only just started playing with PI and watching heaps of tutorials.

[rcheshire (Rowland)]

Great work, Brett. Post it in the Deep Space forum. I don't know if LRGB combination, substituting with your colours will work. Perhaps someone else can comment.

[raymo]

Stunning; nothing to add from a digital newbie's perspective.
raymo

[scagman (John)]

Hi Brett,

Great looking image.

With the STF function I use unlink and then do an auto STF then make adjustments usually linked but can unlink to make adjustment.
If you use auto again it will undo any previous adjustement uyou have made using the STF function. Any adjustments made in the STF aren't permant either. You can drag the new instance icon from the STF bar to the bottom bar in the Hist. transformation function.

Hope this helps ad makes sense.

Cheers

[RickS (Rick)]

Brett,

Detail looks great. Well done!

The reason there is not much variation in colour is that the Ha signal is much stronger than the OIII and the red is overpowering everything. When you do an unlinked screen stretch it will apply a stronger stretch to the blue and green channels to match the red. There's no reason why you shouldn't apply this as a permanent stretch if you like it. As John said, you can drag the new instance icon from STF to the bottom bar of HT and then apply that stretch to your image.

This mismatch in signal levels is very common with narrowband data.

I mangled the colour a bit just to show it can be done. I applied a clipped luminance mask to protect the background and then boosted blue and green with CurvesTransformation. Then just for the hell of it I tweaked the CIE a* and b* a bit. I wasn't aiming for anything in particular - just trying to make it a bit less monochromatic.

BTW, the colour profile attached to your image file looks like it came from your monitor: "Wide viewing angled high density FlexView Display". You might get more consistent results from using AdobeRGB or ProPhotoRGB while processing and then convert to sRGB at the end for web display.

Cheers,
Rick.

[ChrisM]

Brett, that's a magnificent effort for your first image with the new gear. The backlit Bok globules look fantastic and the composition is good.
Chris

[kosh]

Very very nice Brett. You should be proud.
Rick, I love the colour in the reprocess.

Goran.

[Spookyer (Brett)]

I appreciate all the comments. Nice to finally get an image together after months of trying.

Thanks for the reprocess example Rick, I like the colours better. I will go back and try the stretch again and copy down the auto results and fiddle with them, I should be able to get a better spread of colours. I understand that process better now I think. I had the idea in my head from some tutorial or another that you had to have the channel matching for it to "work" and all the colours had to line up on the histogram.

Not sure what happened with the colour space. I normally work in ProPhoto and save out to sRGB for web stuff.

Do you set a colour space in Pixinsight somehow? If not then something must have gone wrong when I did a couple of small touches in photoshop at the end.

Brett

[Spookyer (Brett)]

Here is my revised image. I just stretched each channel separately in the Histogram Transformation tool rather than using just RGB like I did last time. Definitely less monochromatic. I think it is better than my original and closer to what Rick posted.

Must say as a newbie to it the AstroBin site is pretty good to use. I like how you can upload a revised image. On the right side of the page you can click on the original and switch between original and revised images.

http://astrob.in/89863/B/

What do you think?

Have I graduated to the Deep Space forum yet?

[ozstronomer (Geoff)]

Very nice image Brett, nice tight stars and great detail

Colour in narrowband can be tricky, i like your repo.

Cheers Geoff

[Spookyer (Brett)]

Cheers Geoff.

[RickS (Rick)]

Originally Posted by Spookyer

Thanks for the reprocess example Rick, I like the colours better. I will go back and try the stretch again and copy down the auto results and fiddle with them, I should be able to get a better spread of colours. I understand that process better now I think. I had the idea in my head from some tutorial or another that you had to have the channel matching for it to "work" and all the colours had to line up on the histogram.

Not sure what happened with the colour space. I normally work in ProPhoto and save out to sRGB for web stuff.

Do you set a colour space in Pixinsight somehow? If not then something must have gone wrong when I did a couple of small touches in photoshop at the end.

Brett

Your repro looks great, Brett. I think it would do fine in the Deep Space forum

It looks like the image I downloaded didn't have an ICC Profile at all. Under "Edit" you'll find the PI colour management settings. You can set your working colour space there. Use ICCProfileTransformation to convert an image to sRGB colour space and make sure you have ICC Profile ticked in the Embedded Options in the JPG save dialog.

Cheers,
Rick.

[Spookyer (Brett)]

thanks Rick

[SimmoW (SIMON)]

Damn nice update there Brett.

I have no power here, but I'd vote you to be banished to the 'pro' forum!

[LewisM]

Yup, wrong forum. Descend to the lower depths now.

WONDERFUL image!

[cometcatcher (Kevin)]

That's quite spectacular!

[raymo]

You'll make me not want to bother posting my puny efforts.
raymo