Monochrome, IR filters and Confusion

[RichardJ]

Can anybody please explain to me what the effect of the M8 IR problem is on black and white capture. How does the magenta casting manisfest itself on a greyscale?

If Leica decides that fitting an IR filter is the pro tem solution pending a more permanent resolution, would that effectively preclude me from rectrospectivley converting any raw image into monochrome without creating an IR effect?

Am I being stupid here or would the potential solution of a filter to overcome the IR issue simply mean that I would have to remember to dismount the IR filter if I wanted to shoot in monochrome?

Any advice appreciated.

Richard

Just thought of another question, can one mount an IR filter directly on top of an existing UV filter? Cheers

 

[Steve L]

Monochrome will still have IR effects - black gets lighter, green goes almost white in some cases, and skin gets red. Tonalities are jumbled and can't be extracted...

Also the fuzzy focus due to both IR and visible light hitting the sensor at different points will cause lack of focus in monochrome as well as color. This is still anecdotal, haven't seen examples, but people claim sharper images with filter on.

So it looks like you need filters bor both color and B&W, except there are problems with them on lenses wider than 24mm (cyan corners, red center, ???)

I'm still trying to sort all of this out myself, haven't gotten the last word yet from people who have M8's to test on....

 

[John Camp]

I don't think it would have much effect on monochrome. What's happening is that the IR frequencies that normally do not register with a sensor are registering. That means that objects that reflect a lot of IR are registering as more red than they really are. This is most notable on neutral colors like black or grey, although you can see the shift in other colors, too; it seems to me that the most noticable effect that you would have with monochrome is that your blacks might be a bit darker, and the greys a bit deeper, which could be easily fixed in almost any RAW-translation program like Photoshop. (It'd actually be like having a very pale red filter on your camera, and lots of B&W shooters use red filters anyway, by choice.) You'd probably not even notice the effect, though. If it were still light here, I could go out and shoot something black with IR reflection, and then post both the color and the B&W from Photoshop. If I get time tomorrow, I'll try to do that.

The IR cut filters that everybody talks about here (B+W 486) is actually an IR/UV filter which cuts both. You wouldn't have to put the IR over the UV.

JC

 

[J. Borger]

Now we want "TRUE BLACK AND WHITES" ?????
It gets sillier every day ..... since the filmdays we use green filters, infrared filters, red filters, blue filters, orange filters, different filmtypes an developers ... for what??
The digital age opened another box for us .... channel mixer .... just to name a way conversion ................ yeahhh the m8 captures unrealistic B&W tones ..

 

[RichardJ]

Thanks Steve and John for your comments on this. John, I would be interested in seeing an unprocessed B&W conversion posted alongside the colour original. Perhaps you could post a third image, that being the identical image but shot in monochrome mode, just out of curiosity.

I'm not sure of J. Borger's point amidst the seemingly minor rant. I'm aware of the characteristic of most filters in film use because I have been using film for quite some years. However, I don't yet know the characteristics of the M8 sensor. I thought the idea of a forum such as this was to exchange info and experience. I'm just trying to glean a bit of knowledge from others on how this particular camera reproduces monochrome while I await the arrival of my own.


Cheers

 

[J. Borger]

Thanks Steve and John for your comments on this. John, I would be interested in seeing an unprocessed B&W conversion posted alongside the colour original. Perhaps you could post a third image, that being the identical image but shot in monochrome mode, just out of curiosity.

I'm not sure of J. Borger's point amidst the seemingly minor rant. I'm aware of the characteristic of most filters in film use because I have been using film for quite some years. However, I don't yet know the characteristics of the M8 sensor. I thought the idea of a forum such as this was to exchange info and experience. I'm just trying to glean a bit of knowledge from others on how this particular camera reproduces monochrome while I await the arrival of my own.


Cheers

Richard you will be delighted with the B&W tonality....... believe me!
Look forward to your M8 .......

 

[foxwhelp]

As J. Borger's reply suggests -- black & white is inherently unreal -- it's a translation of what we see into something we don't. It's a plastic thing and the relevant question is not whether you get accurate results (you don't, obviously -- you get black, white & greys) but whether you get pleasing results. I don't think anyone has claimed, yet, that the M8 does not give pleasing results.

Another question is whether you can get predictable results -- and yes, you largely can but it requires some thought. The analogy between the M8 and film is very close here -- both require a knowledge of the interaction between emulsion/sensor sensitivity and what you're shooting.

The IR-fuzzy focus thing is a bit of a red herring. Yes, it is true that most lenses do not focus IR light and visible light to the same point. Yes it is true that putting an IR cut filter in front of your lens may increase resolution for that reason. <i>But</i> the only point there is that the resolving power of the M8 with a filter can be higher than its resolving power without one. Even without one, though, it is extraordinarly good.

 

[RichardJ]

Thanks, J. Borger, I am. Tell me though, (I'm fairly new to digital) is it possible to digitally capture in monochrome the "perfectly" exposed shot with every tone behaving as you would expect? This ideal was something we all worked hard to acheive with film. I suspect that this is a redundant question but it "bothers" me that I have to work less hard with digital capture because of the overwhemling latitude I'm offered in post production software packages. I suppose the ideal of the "perfect" exposure is still something I will crave for because whenever I try to use channel mixers, or whatever, I end of with posterised spots or I lose detail in shadows or generally just make a real mess of things. Cheers

Actually, Foxwhelp's reply landed why I was typing this and his second paragraph eloquently anwsers my question, so, thanks.

 

[J. Borger]

Thanks, J. Borger, I am. Tell me though, (I'm fairly new to digital) is it possible to digitally capture in monochrome the "perfectly" exposed shot with every tone behaving as you would expect? This ideal was something we all worked hard to acheive with film. I suspect that this is a redundant question but it "bothers" me that I have to work less hard with digital capture because of the overwhemling latitude I'm offered in post production software packages. I suppose the ideal of the "perfect" exposure is still something I will crave for because whenever I try to use channel mixers, or whatever, I end of with posterised spots or I lose detail in shadows or generally just make a real mess of things. Cheers

Richard .. there is a workflow starting from raw available.
It uses B&W profiles in capture one. These profiles cost less than 25 dollar.
For a complete B&W workflow you set rour camera to capture in jpeg & Raw and set the monitor saturation on B&W ... so you see B&W on your LCD instead of color.
Now if you use the profiles in C1 you also see the raw files in monochrome.
You convert to B&W with these profiles .. using settings without or with "digital" filter (ged, green orange etc. in differet strength).

This is your ticket ..... http://jfilabs.com/ ..

(impressive Contax gallery you have out there BTW: Chapeau!)

(no relations to seller.... etc.)

 

[RichardJ]

Thanks for the link. Incredibly I was just about to post a glowing rave on your gallery too. Very very beautiful photography. Now nobody will believe I meant it.

 

[pfogle]

J B - as per Richard, I find your B/Ws incredible - you seem to get the tonal depth that I've only seen in Ralph Gibson's work - and he never touches digital! I'd love to look over your shoulder one day to see how you do it.

As for IR in B/W - my personal taste is to use the green channel exclusively for IR monochrome - you get a lot less bleed from the overexposed red channel and the contrast in foliage seems to be better to my eyes. Of course this means that the effective ISO is greatly reduced (as the extra sensitivity is mainly in the red channel) and it also means the M8 would no longer have much advantage over other digitals, eg the R-D1.

Still, I think the results are worth it. If you want to try it, you can either shoot RAW and use the channel mixer to extract the green channel, or shoot jpgs with the camera set to monochrome/green filter.

ps in case I misunderstood the OP, and the reference is to whether the extra IR sensitivity of the M8 is an issue for normal B/W work; well, I haven't tried one, but I'd expect the effect to be very slight - a small decrease in shadow contrast perhaps...