Exploiting IR with the M8

[craigrmurray]

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I got my M8 back in November, and have gone through all the whining and growing pains that most everyone else seems to have done, too. I know the augmented IR thing had vexed many on the Forum (me too, but I put the 486 on and just forget about it).

 

Then I thought, "Why not exploit the increased IR properties, for free?" Fuji now offers their Finepix camera without IR filter for law-enforcement use, plus many other DSLRs can be modified to do the same.

 

So I bought a 49mm B&W 092 IR filter, which is the dark red one that blocks most visible light (heretofore abbreviated to VL). In the M8 the filter factor (in black and white) is about 5 stops more exposure than for visible light.

 

Here's my question: has anyone else on the forum played around with this? Most of my pix seem a little soft, but isn't that the nature of IR photography vs. VL photo?

 

I know that the focus point shifts closer than VL does on the focusing scale, and it's been 25 years since I tried shooting IR B&W film (boy, was that a pain in the ass!) Plus, here in the Midwest, most of the foliage is dead, so you don't have all those beautiful hazy-white trees that you do when it's warm. I haven't tried any portraiture yet, but that's next.

 

If anyone requests it, I could post some side-by-side pix shot with and without the IR filter.

 

Heigh ho.

 

Craig

[wstotler]

That sounds really, really cool. Can you please post some examples?

 

Thanks,

Will

[grober]

You've given me the idea to pull out my old, dark red Leica 39mm filter and fool around in B&W too tomorrow when the sun's up.

 

Sure: post 'em! We'd love to see what you're getting.

 

-g

[Hans Roggen]

Could you post some examples?

 

Hans

[leicajh]

Sony got into some hot water a few years ago when some clever photographer experimented with their "Night Shot" video camera. When a dark IR filter was placed on the camera in the Night Shot mode, the camera could see thru bathing suits.

[lars_bergquist]

Günther Osterloh gives this recipe: Tape a narrow strip of millimetre-squared paper along the focusing scale, with one division exactly on the ? (infinity) mark. Now put the camera on a tripod and an IR filter on the lens, and do a series of exposures of a sharply delineated subject at optical infinity (= at least 1000 X the focal length). Begin at infinity and then move the focusing helical around 1 mm for each exposure. Later, mark which exposure was sharpest. The distance is where you put your own IR focusing mark FOR THAT LENS. This is the distance that you adjust the focus for every subject distance.

 

The old man from the Age of Adhesive Tape

[Vivek Iyer]

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I don't have an M8. Here are some snaps from the Epson R-D1s and a 700nm IR filter.

 

For focusing, use the the red dot (IR mark) for IR focus. This, in fact, will vary according to the thickness of the filter. Since it is digital capture, it is easy to calibrate it by trial and error.

 

You can also use a flash!

 

The outdoor examples are from Kijkduin last week.

 

BTW, the 700nm filter I used is an equivalent of your B+W filter