Colorize inverted image issue

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Jordan Konisky
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Colorize inverted image issue

Post by Jordan Konisky »

Image15_25_47Z_l4_ap2195imppg1.75invcolor by Jordan Konisky, on Flickr

When I invert an image via imppg and then colorize in photoshop, the background remains white (see attached). How do I convert this background to black? Thanks for suggestions and help.

Jordan


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Re: Colorize inverted image issue

Post by Montana »

Unfortunately if you invert black, it becomes white ;)

You would need to select that portion of the image with a mask and only invert the disc space. I can't imagine it would look nice. This is one reason I am never a fan of inverted images. I don't like white sunspots, they just look wrong to me. I did once colourise an inverted image so that it had a blue background. I would love to remember how I did that :? even better, where is that picture?

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Re: Colorize inverted image issue

Post by nicspenceryork »

I’m with Alexandra in finding inverted white sun spots less easy on the eye! I do however like an inverted spotless disc edge/limb with a white prom and darker sky and there’s a ‘double inversion’ technique in Simon’s video which was a game changer for me.

Watch this about 32 minutes in:

https://www.youtube.com/watch?v=-zD4EIGBess

Good luck with it


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Re: Colorize inverted image issue

Post by Montana »

That's a video gem, thanks Nic. I never knew you could twist the histogram on its head like that. You learn something new every day!!

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Re: Colorize inverted image issue

Post by Ivan »

Jordan Konisky wrote: Fri Sep 24, 2021 4:56 pm

When I invert an image via imppg and then colorize in photoshop, the background remains white (see attached). How do I convert this background to black? Thanks for suggestions and help.

Jordan
If I need a dark background on inverted photos, I use roughly the same curve settings in ImPPG. The light spots look a little odd though.
1.jpg
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Ivan


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Re: Colorize inverted image issue

Post by Merlin66 »

Alexandrs,

The blue background etc usually happens when you invert only one colour of an RGB image.


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Re: Colorize inverted image issue

Post by DeepSolar64 »

In GIMP I use select-by color and then use black to replace the white background with black.

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Re: Colorize inverted image issue

Post by GregA »

In Gimp, I use curves on the grayscale first, ramping up from black towards white and then back down. One trick is to move the starting point to the right a bit to blacken the glow a bit more without harming the prominences. Then I tweak the RGB curves.
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Re: Colorize inverted image issue

Post by Radon86 »

Jordan Konisky wrote: Fri Sep 24, 2021 4:56 pm Image15_25_47Z_l4_ap2195imppg1.75invcolor by Jordan Konisky, on Flickr

When I invert an image via imppg and then colorize in photoshop, the background remains white (see attached). How do I convert this background to black? Thanks for suggestions and help.

Jordan
Hi Jordan,
I tend not to work on inverted images, but my understanding is like that of Alexandra. If you can make a selective mask of the area you are working on, you can make changes only to that area. The background can be worked on separately in Photoshop, you can do almost anything you like.

If you have not done so, getting a grip on selection and masking in layers - see :
https://brierleyhillsolar.blogspot.com/ ... rials.html

(Ken Crawford tutorials).
Me? I have tried to teach myself from scratch all the basics of Photoshop including selection, brushes, masks and alpha channels, including Photoshop layers book - excellent for general photography if you have not mastered this !

Magnus


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Re: Colorize inverted image issue

Post by Radon86 »

Jordan,
I could not access your image you indexed in your original post. Do you want to show us what you are working on/having problems with ? Maybe one of us can show you the steps towards the goal you are aiming for.

Good imaging and may I wish you the Season's Greetings!

Magnus


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