Narrowband help wanted please!

[swag72]

I have been trying to get a nice hubble palette image for ages, but just can not get there.

I have the following data 12x1500s Ha, 12x1500s O3 and 12x1500s S2. I have put them into PS as S:Ha:O3 as I read on the Starizona site that gives the classic hubble palette for starters.

I have attached a screenshot of what I am getting once the data is mixed as above as well as all the layers down the side that are open and attiributed to each colour / filter. Is there a layer I am perhaps missing in all of this? Should I be blending it all differently? Everything is just very green and I can't get rid of it.

I would really welcome some pointers, perhaps it's as simple as not having enough S2 and O3 data?

[steppenwolf]

Hi Sara, what you have right now is the standard 'Hubble Palette' in that you have combined the channels mapping SII to Red, Ha to Green and OIII to Blue. However, the most popular representation of the palette is the 'yellow and turquoise' style that I suspect you are looking for? The image below is my attempt at it using your data - is this what you were looking for? If so, I'll show you how to do it. If not, thanks for the opportunity to play with your data!!

[dmahon]

I got some tips from Martin_H in a thread I started about Hubble processing (of the same target) a fortnight ago.

http://stargazerslou...elp-processing/

Which would end up with something like this:

[swag72]

Brilliant, brilliant both - Just what I was after, although they are both different

Steve - Can you tell me how on earth you got there and now I'm off to read the thread mentioned above. I can't believe you got both of those from the screen grab I had.

Thank you, thank you!!

[steppenwolf]

Steve - Can you tell me how on earth you got there

it's never easy working from data that has already been stretched and so on but the basic principles worked OK on the screen grab!

1. I opened the 'Levels' dialogue box and the histogram view with Channel set to 'Colours' and adjusted the green and blue to overlap the red thus equalising the colours

2. I applied the colour noise filter at 100%

3. I reduced the magenta level in Colour Balance.

4. I applied the 'Selective Colour' settings from my image processing article in S @ N magazine:-

(1) Selective Colour Adjustment 1

Convert the green colours to a warmer, more yellow colour. Select Image – Adjustments – Selective Colour then choose ‘Greens’ from the drop-down menu. Reduce the Cyan level to –100% and the Magenta level to –30%.

(2) Selective Colour Adjustment 2

Enhance the fairly light yellow detail further by making it more gold in appearance. Select Image – Adjustments – Selective Colour then choose ‘Yellows’ from the drop-down menu. Reduce the Cyan level to –100% and increase the Magenta level to +40%.

(3) Selective Colour Adjustment 3

Shift the cyan components towards blue. Select Image – Adjustments – Selective Colour then choose ‘Cyans’ from the drop-down menu. Increase the Cyan level to +10% and reduce the Yellow level to -100%.

(4) Selective Colour Adjustment 4

Adjust the cyan components by the reduction of both magenta and yellow. Select Image – Adjustments – Selective Colour then choose ‘Cyans’ again from the drop-down menu. This time, Decrease the Magenta level to -30% and the Yellow level to -100%.

5. I boosted the colour saturation

I hasten to add that this is not my own special method, it is a well documented process but I use my own percentages to suit my taste (or lack of it!) in colouring.

[swag72]

Thanks so much for that excellent detailed explanation Steve. Here's what I got from there.

[martin_h]

Well done! looking good so far, but don't forget basic processing! I took a screen grab of your image and aligned the black points to get this...........

[Spikey]

Great work Sara, I get the following; pretty similar to the others.

[swag72]

Thanks for those edits and thanks for the pointer about the black points as well Martin - Duly noted and edit completed.

How do you get the pictures to be thumbnails until you click them? I've tried all ways and can't work it out!!

[Spikey]

You've got a fantastic image there now Sara, really well done.

The thumbnail tends to work when the pic is an attachment and not an embedded link from your gallery or album.

[steppenwolf]

Well done, Sara, you are so getting there!

[Black Knight]

I love this image Sara. As one who is soon to embark on narrowband imaging with my new 314L+, I've found this thread to be invaluable.

[swag72]

Thanks Simon, Steve and Andy.

I have to say that once I'd mapped the images into the hubble palette, Steve's written account was brilliant. I then adjusted the black point as Martin said and then just went back to the selective colour palette and got more yellows and cyans.

I followed http://starizona.com/acb/ccd/software/ps_clipping.aspx to the letter and changed the mapping to SHO as per this page http://starizona.com/acb/ccd/advimnarrow2.aspx

Hope that helps and others find that useful.