My way of removing the magenta cast manually

[martinb]

1. Open up the RAW or TIFF file in Photoshop, preferably in 16-bit.

2. Go to Image - Adjustments and choose Selective color...

3. Under Selective color you click "Colors" and choose "Magentas".

4. For this image I used about Cyan +40, Magentas -100 and Black +100 I think. You can tweak this the way you like, but the key is to bump cyan slightly, reduce magenta a lot and bump the black.

5. If you're having troubles with magenta in reds you choose red and reduce magenta there. If you're getting trouble with cyan after removing the magenta in blacks you choose cyan and adjust the cyan level there.

6. Finally I darken the black and shadows a little using curves or levels.

This example might not be perfectly done, but this only took a couple of seconds. If interested I can show my method on removing cyan corners as well.

Cheers,

Martin

[stunsworth]

The problem is when there are objects that are genuinly magenta in the image. Using a filter is more predictible.

[fursan]

Yes please Martin. Filters seem to be a long time coming!

Regards

Originally Posted by martinb

1. Open up the RAW or TIFF file in Photoshop, preferably in 16-bit.

2. Go to Image - Adjustments and choose Selective color...

3. Under Selective color you click "Colors" and choose "Magentas".

4. For this image I used about Cyan +40, Magentas -100 and Black +100 I think. You can tweak this the way you like, but the key is to bump cyan slightly, reduce magenta a lot and bump the black.

5. If you're having troubles with magenta in reds you choose red and reduce magenta there. If you're getting trouble with cyan after removing the magenta in blacks you choose cyan and adjust the cyan level there.

6. Finally I darken the black and shadows a little using curves or levels.

This example might not be perfectly done, but this only took a couple of seconds. If interested I can show my method on removing cyan corners as well.

Cheers,

Martin

[martinb]

Originally Posted by stunsworth

The problem is when there are objects that are genuinly magenta in the image. Using a filter is more predictible.

No doubt about it, but sometimes you may not have the necessary UV/IR filter or you get crazy cyan corners from your wide angles because of them.

[martinb]

Originally Posted by fursan

Yes please Martin. Filters seem to be a long time coming!

Regards

I'll do that in the evening.

[ChrisC]

Martin - I would do that on a separate layer. Then paint in only those areas which need the magenta correction; this can be done by utilising a filled layer mask on the new layer and mask removing to correct where appropriate, or by 'painting' back the correction using History Brush.

...................Chris

[Skippy Sanchez]

Originally Posted by ChrisC

Martin - I would do that on a separate layer. Then paint in only those areas which need the magenta correction; this can be done by utilising a filled layer mask on the new layer and mask removing to correct where appropriate, or by 'painting' back the correction using History Brush.

...................Chris

hi martin-
the idea of using layers is the way to go. most of my personal stuff is b/w, but when i'm using the M8s on assignments that require color, here's what i do. it works out very well when it comes to synthetic blacks:

create a new layer, desaturate 100%, bump up contrast a touch when needed, then click HIDE LAYER MASK, which brings the color layer to the surface.

then, with the background selected as black, use the paint brush tool (hard light/100%) to 'erase' or paint out the synthetic fabrics revealing the desaturated layer beneath. by switching the background/foreground colors, i can clean up any sloppy edges. the "["and "]" keys easily decrease & increase brush sizes.

granted, it can be a bit tedious if you have a lot of painting to do, but it really works well & the blacks are true black.

on the same subject, i shot some police officers talking with neighborhood watch folks, and their synthetic green shirts turned a muddy magenta/brown.

i desaturated my layer to gray, then adjusted the color in levels (it's still an RGB file) to the original moss green, then continued with the same technique noted above. it's a pain in the ass when you don't have filters, and i sure wish it wasn't necessary, but there are ways to correct most of the IR problems in photoshop.

it takes longer to explain how to do it than it does to actually do it in most cases.

[jaapv]

It is strange - I walked into my camera shop yesterday; Leica filters were freely available. I bought a 39 mm one.....

[Skippy Sanchez]

Originally Posted by jaapv

It is strange - I walked into my camera shop yesterday; Leica filters were freely available. I bought a 39 mm one.....

Well, I know they're out there, but I'm still waiting on two of four freebies from Leica for my 21f/2.8 & 90/f2.

I've got 2 M8s and a stable of lenses, but I'm not made of money. At least not any more.

[carstenw]

Another batch just got shipped. I bought a 46mm chrome one at Leica Berlin, and they have others in stock at the moment.

[martinb]

Wow! is there a thing called layers in Photoshop??? Didn't know about that.. Just kidding. For this image I found painting wasn't necessary and I'm not a perfectionist about color either.
But adding an adjustment layer + mask and paint is of course a way to improve this method if you have the time and find it necessary.

[martinb]

Fursan,
As you probably undertand you repeat the same steps in selective color, but choose cyan instead of magenta. Here you only have to play with the cyan slider. I put it on -50 on the shot below. When removing cyan in corners, an adjusment layer and mask will be useful and just paint away the cyan.
The lens here was an uncoded and unfiltered pre-asph elmarit 21mm.

[eyejockey]

I have found that Color Mechanic Pro is a very fast way of removing or adjusting magenta , cyan, or any other divergent casts within PS CS3. The CS3 Beta plugin has just been released.

Color Mechanic Pro 2.0 Beta

The software can differentiate betwween different shades of magenta which may look identical but in fact are not. It is also very fast. One filter, a couple of adjustments and you are done.

Stephen Goldblatt

[Ben Marks]

Just used the method that started this thread. Quick. Painless. VERY helpful. Thanks buckets.

Ben Marks

[martinb]

Thanks Ben! Glad it worked for you. If you look at the top example you will see that magenta just doesn't affect black fabrics. The ground is also slightly magenta.

[newyorkone]

Great thread guys. Thanks for the info and tips!

Even though I have received my two filters, I still prefer to shoot without them if possible.