Filter for red objects using FP4

[Jmarmck]

Visable light: red=red green=green, blue=blue
False Color (IR)- Remember, you cannot see the IR so it is represented in the next closest band, Red.
So it goes like this.
Red=IR, green=red, blue=green........blue is not visible. This is partly why water (particularly clean water) in IR imagery is black, no return from any of the bands. Muddy water will be cyan (green and blue so red and green respectively)

So the red in the meat will should go to a greenish color.

[bob carnie]

There is no blue in the original scene so I am ok, and I am shooting infared BW so I assume as you are indicating I will see detail . Yes ? No

Visable light: red=red green=green, blue=blue
False Color (IR)- Remember, you cannot see the IR so it is represented in the next closest band, Red.
So it goes like this.
Red=IR, green=red, blue=green........blue is not visible. This is partly why water (particularly clean water) in IR imagery is black, no return from any of the bands. Muddy water will be cyan (green and blue so red and green respectively)

So the red in the meat will should go to a greenish color.

[bob carnie]

I wanted to consume this project afterwards - price of meat is crazy - what about spraying with an edible dye .
Is not glycerin just clear? I get the specular thing. but the meat will need to be rendered in the final print as the darkest object with detail. not a lot of specular highligh, I will leave that to the bone matter.

That would be interesting. I am going to predict that you will get black meat. infra red in not the same as red. It is in effect heat given off as a wavelength. Because IR penetrates through the skin it comes up white on people as it records the IR radiation from within. I expect room temperature meat to be the same image tone as room temperature anything else. In this web site there are colour infrared pictures of cold blooded animals.
http://coolcosmos.ipac.caltech.edu/i...zoo/index.html
I think Drew's idea of spraying a glycerin solution is a good one. The problem is similar to black animals, they need specular highlights.
Since your meat is red in the highlight surfaces and in the shadow creases (albeit different tones), filters won't distinguish one from the other.
Perhaps the appearance might be different if the butcher can cut cross grain or end grain or side grain, or saw grain or scalpel slashes
Regards

[Jmarmck]

With BW I honestly don't know. I would hazard that it would not. But if you add a green filter to increase the range of tones from the green spectrum then I cannot see how IR would bring out the reds. Again, it is just a guess.

Of course by the time you figure this out, the meat will be gray.

[Drew Wiley]

Another meat counter trick - red dye? Yeah, they do that too, even though it's illegal here. I just don't know exactly how common food dye responds to film.
Easy enough to try. But gosh, if your prints are anything like what comes over the web, a really dark print with a lot of deep tone gradation plus specular highlights
looks impressive. I only seem to get away with that kind of thing when using true old school "straight-line" films like Super-XX, Bergger 200, or Foma 200. Otherwise, I gotta overexpose then mask. Do you intend to eat the meat raw or cooked, Hannibal?

[Andrew O'Neill]

Wratten #11

[Drew Wiley]

A Wratten 11 or equivalent Hoya XO merely makes typical pan film sensitivity analogous to that of normal human vision by leveling out the minor dip in the green part of the spectrum. In other words, the effect is relatively minor. A deep green filter, on the other hand, would significantly darken the red of meat and accentuate the highlights via greater contrast. Looks like an interesting photo project, if indeed a bit Medieval.

[LabRat]

So it seems you mostly want to lighten the reds, so try a #25 or #29 red gel + warm cast lights... (I use a #29 to create a "pseudo" IR effect sometimes...)

FWIW, you better get cracking with this project, before the baby maggots start wiggling and waving at 'ya... ;-) Maybe a better winter project in a COLD studio... And don't let the neighbors see this... (Momma told 'ya, "never play with your food") :-(

Steve K

[EdWorkman]

Red filters will lighten red a lot, plus you will lose a lot of speed.
I've used yellow K2 to separate red from gray without turning the red to white

[Jac@stafford.net]

Red filters will lighten red a lot, plus you will lose a lot of speed.
I've used yellow K2 to separate red from gray without turning the red to white

Yeah, but remember the red filter is a Contrast filter which implies that it lightens compared to the rest of the colors in the frame.
.