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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Montana
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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?

Alexandra


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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
1.jpg (127.55 KiB) Viewed 351 times
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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