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Getting "Ektachrome Infrared" colors out of the M8

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OK, so I was shipped a 39mm Leitz IR filter (deep red, almost black) by mistake for a Leica UV/IR filter - and decided to keep it.

 

Playing around, the first thing I noticed is that while the M8 replicates B&W infrared film quite nicely, color IR shots are nothing like color Ektachrome Infrared. They are either red all over, or, with a strong bias of the white balance towards the left (yellow, + green tint), a weak approximation of EIR shot without a filter - pastel purples, magentas and reds.

 

Where were all the rich greens and cyans and flaming red foliage I remembered from shooting film EIR? You know, the colors the CIA would analyse to figure out the Soviet crop forecast, and so on.

 

I've now figured out how to get those colors back - and it basically involves replicating how Kodak sensitized the three layers of EIR. What Kodak did was to mismatch the wavelength sensitivities of the layers to their color dyes, so that infrared light created a red image (cyan dye layer), red light created a green image (magenta dye layer), and green light created a blue image (yellow dye layer). Blue light affected all the layers, and created that purple look if no filter was used, so the normal way to shoot EIR was with either a yellow or a normal red filter (not IR-only) to block all blue light.

 

So - what I've done is to shoot TWO exposures of these scenes - one with the Leitz IR-only filter, and one in "normal" RGB.

 

I open the normal color shot in photoshop, and swap some color channels. Green channel gets copy/pasted into the blue channel, red channel gets copy/pasted into the green channel. Then I open the IR exposure, and copy THAT red channel and paste it to the red channel of the "normal" color image. So I've now got Infrared>red, red>green, green>blue.

 

This replicates the look of EIR shot with a yellow filter - firey red grass and trees, cyan skies, and some neutral tones that look almost color-correct.

 

For the look of EIR shot with a red filter (which produced IR and red images but no green exposure) I just take the additional step of filling the blue channel with black (no exposure). This gives the same intense red/yellow/green pallette.

 

It takes a bit of further processing with "selective color" and "HSB" to get the colors precise, but that is pretty easy once the basic palette is in place.

 

I figured this was M8-specific, even if it is a post-processing technique. Unless you do surgery on a DMR or D-Lux 4 to take out the IR filters, it doesn't apply to them.

 

------

 

P.S. You'll notice the clouds moved between the IR and normal color exposures, thus the cyan/red/white effect. I also shot this first set of pix hand-held, but it really requires a tripod for the two exposures to match - amazing how a fraction of an inche can change how things align even at 50-60 feet away!

Edited by adan

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OK - a couple more, this time showing the difference between a simulated yellow and red filter. The yellower picture is the red-filter simulation (yeah, I know - but that's how color infrared works). The leaves blew in the wind, adding to the headaches of shooting without a tripod.

 

Here's a link to some "real" Ektachrome EIR (R.I.P. 2007): http://www.vividlight.com/articles/3113.htm

Edited by adan

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.....I've now figured out how to get those colors back - and it basically involves replicating how Kodak sensitized the three layers of EIR. What Kodak did was to mismatch the wavelength sensitivities of the layers to their color dyes, so that infrared light created a red image (cyan dye layer), red light created a green image (magenta dye layer), and green light created a blue image (yellow dye layer). Blue light affected all the layers, and created that purple look if no filter was used, so the normal way to shoot EIR was with either a yellow or a normal red filter (not IR-only) to block all blue light.

 

So - what I've done is to shoot TWO exposures of these scenes - one with the Leitz IR-only filter, and one in "normal" RGB.

 

I open the normal color shot in photoshop, and swap some color channels. Green channel gets copy/pasted into the blue channel, red channel gets copy/pasted into the green channel. Then I open the IR exposure, and copy THAT red channel and paste it to the red channel of the "normal" color image. So I've now got Infrared>red, red>green, green>blue.

 

This replicates the look of EIR shot with a yellow filter - firey red grass and trees, cyan skies, and some neutral tones that look almost color-correct.

 

For the look of EIR shot with a red filter (which produced IR and red images but no green exposure) I just take the additional step of filling the blue channel with black (no exposure). This gives the same intense red/yellow/green pallette.

 

It takes a bit of further processing with "selective color" and "HSB" to get the colors precise, but that is pretty easy once the basic palette is in place.

 

 

 

With a lot of help from various people here, I've gotten much better at doing IR shots, but none of them remind me of what I used to do with film. Your examples up above pretty much match what I thought I was going to be getting.

 

So, I guess the next step is to get out the tripod, and shoot two frames with the M8 as described above. I assume when I'm using the IR filter, I leave the white balance as "auto" and don't do a custom white balance, right?

 

Here's my question. You said "Green channel gets copy/pasted into the blue channel, red channel gets copy/pasted into the green channel. Then I open the IR exposure, and copy THAT red channel and paste it to the red channel of the "normal" color image."

 

I'm not all that great at using Photoshop. I've just learned how to use the "Channel Mixer" function. How do I copy one channel to another, especially if it comes from another image? I don't even know where to start.

 

(Can this be done in Lightroom??)

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Andy--thanks for the pointers; looking forward to trying them.

 

... one with the Leitz IR-only filter, and one in "normal" RGB ...

Is "normal" RGB with or without UV/IR-Cut filter?

 

 

 

There was also an LFI article spread over two issues maybe a year or so after the M8 came out, giving some hints for "creative" IR color. IIRC the images were interesting, but not as stunning as what you're getting.

 

 

... the colors the CIA would analyse to figure out the Soviet crop forecast, and so on ...

Aha! So that's why EIR is discontinued! Once the Soviet Union disappeared, Kodak quit getting all those big CIA film orders...

Edited by ho_co

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...So - what I've done is to shoot TWO exposures of these scenes - one with the Leitz IR-only filter, and one in "normal" RGB.

 

I open the normal color shot in photoshop, and swap some color channels. Green channel gets copy/pasted into the blue channel, red channel gets copy/pasted into the green channel. Then I open the IR exposure, and copy THAT red channel and paste it to the red channel of the "normal" color image. So I've now got Infrared>red, red>green, green>blue.

 

 

I've been trying to figure out how to do this, but things are not working too well. My problem is that I don't know Photoshop well enough. Specifically, how do I copy one channel into another?

 

I'm also not sure how to copy a channel from one image to another image. I assume the camera needs to be on a tripod to take these two images, so things will overlap properly (unless they're clouds...).

 

I thought I figured out how to do this - select the window for "channels", then click the small button at the bottom left to select a channel, and then do a control-c to copy. Then deselect it, select the next color channel, and do a control-v (paste). Maybe this is how things are to be done, but my results don't look anything like the example posted above. I think I'm just not doing this properly....

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Mike, I think your channel-copying technique is correct, but I'm with you in needing instruction here. Maybe some Photoshop Masters will clarify.

 

There may be some difference in using this sequence instead:

Choose "Channels" tab.

Select the channel you want to copy (from) by clicking its name.

(This step is apparently optional: ) Select all (Cmd-A).

Copy (Cmd-C).

Select the channel you want to modify (copy to) by clicking its name.

Paste (Cmd-V).

 

(The "Load channel as selection" icon and "Save selection as channel" icon seem to behave a little differently from this method.)

Edited by ho_co

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There may be some difference in using this sequence instead:

Choose "Channels" tab.

Select the channel you want to copy (from) by clicking its name.

(This step is apparently optional: ) Select all (Cmd-A).

Copy (Cmd-C).

Select the channel you want to modify (copy to) by clicking its name.

Paste (Cmd-V).

 

 

Thanks!!! Apparently the step I didn't realize I needed, was "Select all" (ctrl-a), before I did the "copy". Now that I've got that working, things are looking better. My trial photos were taken just before sunset, which I thought would give me even more IR, but apparently that's not the case. Will take another pair of photos tomorrow. In the meantime, I'll see if I have another pair of images I can practice with.

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If someone who knows Photoshop well is reading this, maybe you can help explain how to do the following step:

 

"For the look of EIR shot with a red filter (which produced IR and red images but no green exposure) I just take the additional step of filling the blue channel with black (no exposure). This gives the same intense red/yellow/green pallette."

 

 

How do you fill a channel with black (no exposure)? I don't understand what this means, let alone how to do it. If it's "no exposure", I can understand why that color channel should be black, if it were film, but how do you make that happen?

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How do you fill a channel with black (no exposure)? I don't understand what this means, let alone how to do it.

It just means “Make it all black”. There are probably dozens of ways to achieve this; for example, you could select black as the background color, select the blue channel, select all, and delete.

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Mike--

As a follow-up to Michael's post, I just learned at one of the Kelby traveling Photoshop seminars that:

opt/alt-delete = fill with foreground color

cmd/ctrl-delete = fill with background color

 

If you've changed your foreground and background colors from black and white, you can restore them by pressing D ( = 'Default' ).

And to exchange foreground and background colors, press X.

 

 

 

So far, I've been trying to follow this thread mentally and haven't had a chance to put it into practice. So maybe you could help me on this:

 

When Andy says:

... one with the Leitz IR-only filter, and one in "normal" RGB ...

for the "normal" RGB picture, are you using the UV/IR-Cut filter or not?

 

Thanks!

Edited by ho_co

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Thanks for the new information - that will be the next thing I try.

 

As to how I'm doing this, I've got a fifty-year-old filter that looks black until you hold it up to the light, when it looks like a very, very dark red. I think its an IR filter I bought way back when, but I've got no idea what it really is.

 

I'm not using any other filter. I'm taking the "normal" shot with no filter on the lens, and then taking an IR shot using only what I think might be my IR filter. Neither am I changing the white balance - I've been leaving it on "automatic".

 

I'll attach a pair of images here; the first is the "normal" shot, and the second is after trying the above technique, and then bumping the saturation quite a bit. I'm not sure if this is what I'm supposed to get or not, but it's... well, different! Obvious problems I learned today are that if the tripod moves at all, the photo is ruined. Also, if I'm not very quick at taking the second photo, the clouds move, and again things look "wrong". I don't like bumping the saturation as much as I've been doing, but if I don't, the photos don't look like what I remember - or the examples of IR film posted earlier in this discussion.

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Thanks, Mike! I think you've got it, and you've got me interested in getting out and trying it!

 

 

Technically, the filter you've got isn't a true IR filter, but it's what everyone uses for the purpose. A "true" IR filter is opaque to the eye. The problem with it is that it transmits only IR, and most if not all IR films had sensitivity into the red portion of the spectrum.

 

What that means is that a true IR filter (also called a "black" filter) was fiddly. It let through only IR, and no exposure meter was calibrated for IR. That meant guessing and bracketing. And since it didn't pass any of the visible spectrum, exposure times tended to be long to boot. The red sensitivity of black-and-white infrared films meant that the deep red filter was much more convenient.

 

That's why what you and Andy and I have is a filter that looks black till you get it to your eye, when you discover that it does transmit some red: So far as I know, the only use a 'true IR filter' had was technical and scientific. I think most photographers refer to this extremely dense red filter as an IR filter.

 

 

Sorry that sounds so pedantic.

I never used a true IR filter, but I did read about them many years ago as a child.

Edited by ho_co

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It is really a matter of degree. A 720 or 715 nm filter will block virtually all the visible light while a 780 nm filter will look just as black, but held against the sun reveals that it is actually a very dark red. A 830 or 850 nm filter will let even more of the red light pass through. All these filters (and there even more, both stricter and less strict) are advertised as IR filters, and that’s what they are; there is not a single kind of filter that was the real, genuine IR filter.

 

The filter used in the series of articles in LFI was a Heliopan RG 780, btw.

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A 720 or 715 nm filter will block virtually all the visible light while a 780 nm filter will look just as black, but held against the sun reveals that it is actually a very dark red. A 830 or 850 nm filter will let even more of the red light pass through.

Oops, of course it’s the other way round: A 830 or 850 nm filter will block virtually all the visible light while a 780 nm filter will look just as black, but held against the sun reveals that it is actually a very dark red. A 715 or 720 nm filter will let even more of the red light pass through. Sorry about the confusion I might have created.

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Just a few random thoughts...

 

The Leica M8 seems ideal for taking both "real" IR photos (which to me seem to look best in black-and-white), and also replicating the "look" of Kodak's IR Ektachrome, at least for stationary objects. The biggest problem I had, was in learning how to get Photoshop to process the images.

 

"Real" IR Photos

I'm not so sure I understand what's going on behind these processes. In the case of a "real" IR photo (a single image, taken through an IR filter), I'm guessing that a photo taken by IR light won't have any color in it, and the only reason my IR photos look red is because they're letting some visible red light through. So, once the photo has the color removed, the result is a true IR photo (and using the "black" filters might get a more accurate result). The colored images I've gotten from these seem interesting, but not as colorful as those to replicate what the IR Ektachrome produced.

 

 

IE Ektachrome simulated images

I think what we've decided is that Kodak's IR Ektachrome isn't really what I used to think it was. Apparently it's designed to display certain colors, based on the type of light reaching it. Certain types of light create a "red" color, and others create different colors. It's like a "fake" photo, that happens to look quite strange - and as was noted, these false colors can provide a lot of information to someone who knows what they mean. The choice of what colors were produced by IR film is simply what Kodak decided they should look like, based on the light reaching the film. (If that's the case, nowadays there's nothing wrong with playing with Photoshop until the colors look the prettiest. Why be limited to what Kodak decided on.) I'm following the technique described up above, taking two images, one "straight" and one through the IR filter. I've been letting the M8 figure out the exposure, and I've manually been adjusting the focus setting for the IR image by an amount that seems to work best for me. I've been trying to exclude anything in my images that moves between the first and second image.

 

 

B&W

Next steps for me are to figure out the best way to convert "real" IR images from the purplish images I'm now getting, to b&w. Is this best done in the camera, or in Photoshop? ...and what's wrong with simply using the "saturation" tool to remove all the color information? I read that above, but now I've got to read up on the best ways to convert color images to b&w. This isn't really an IR question - I should probably do this several ways, and see which looks the best.

 

 

Lightroom

I've recently started learning and using Lightroom. The "channel" modifications I've been using up above were done in Photoshop. Does anyone know if Lightroom includes the tools to do this?

 

 

Behind the scenes

At some point I need to figure out the "why" of what I'm doing to replicate the IR Ektachrome. It's like a menu - follow these steps, and you get the finished photo. I guess I need to understand more about what the IR Ektachrome film was doing, so I can then understand why I'm moving the information around between channels. I wish there was a way to do this with a single exposure, as working with two images means you can't shoot anything that moves - for example, people. This is explained in a lot of detail earlier in this discussion, but I need to read and study it long enough so I understand what's going on.

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Michael--thanks for the clarification! I knew I was on shaky ground, and you moved me back to solid!

 

 

Mike--

In regard to EIR: Yes, it's simply a false-color film.

 

In regard to color: A DNG has all the data the sensor caught, so it's always in color with the M8. The red-sensitive cells of the sensor will be interpreted as red by your DNG converter.

 

One quick way to get a straight IR image from the camera is to use JPG set to black-and-white. That won't give you the control you have with the DNG, but is simple and direct. And if you save a DNG as well, you still have flexibility for the future.

 

You could also use just the red channel and convert to monochrome in the channels panel. Or do the same in Image > Adjustments > Channel Mixer....

 

In regard to black-and-white: Desaturation is one route. A couple years back, LFI included a very sophisticated methodology that CS4 Image > Adjustments > Black & White... emulates but greatly simplifies.

 

You're right, experimentation is the way to get it right.

Edited by ho_co

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Hi - on vacation, so not keeping up every day - looks like you figured out the channel copying and filling issues. Hoco - I used uvir filter for my normal color shots just for maximum differentiation from the pure-IR shots.

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