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# Thread: HELP ASAP! IR question before I fly out!

1. ## HELP ASAP! IR question before I fly out!

Originally Posted by MattKing
Stone:

This may be too late, but just in case it isn't ...

Your question about the effect of temperature indicates to me that there is something about (near) IR film that you are misunderstanding.

None of us use a meter that will tell us how much film sensitive radiation there is in the scenes we photograph.

All of our calculations are based on:

1) we know that the light we see reflected off our subject is accompanied by at least some IR that our film is sensitive too; and
2) we have or gain experience as we go about what the percentage is of IR light reflecting from the subject.

As an example, we learn from experience that in certain weather conditions, at certain times of day there is a relatively high percentage of ambient IR in the total ambient light available. We also learn that certain types of vegetation reflect more of that IR than other types do.

If we didn't use something like a very dense R72 filter, we would never see any IR effect on the film, because the film is much more sensitive to visible light then it is to IR.

We have no way to meter the IR. We do, however, have a way to meter the visible light, and through experience we learn how much IR is around when a certain amount of visible light around, so we do have a way of approaching the problem.

First, we put something like an R72 filter on the camera, which blocks out almost all the visible light, but transmits the IR. We do not meter through that filter - use a separate hand-held meter.

Next, based on our experience that indicates that for any level of illumination we see, there are about 6 stops less intense IR present as well, we measure the visible light, and extrapolate the IR by assuming there are 6 stops less available. We accomplish that extrapolation by metering at EI 6, which is 6 stops less than EI 400.

Finally, we expose the film through the filter, and bracket around that 6 stops less estimate, because it isn't nearly as accurate as our usual metering technology.

Hope this helps.
Thanks, this was the conclusion of the many posts above but much more concise

Ok zzzzz hike out tomorrow, just concerned the post office had trouble tracking the film today... Ugh....

~Stone

Mamiya: 7 II, RZ67 Pro II / Canon: 1V, AE-1, 5DmkII / Kodak: No 1 Pocket Autographic, No 1A Pocket Autographic | Sent w/ iPhone using Tapatalk

2. ## HELP ASAP! IR question before I fly out!

Update:

Just got back... So sad news is that the post office failed to both deliver the film, and deliver the newly bought filter on time so I didn't have any of it until after I hiked out.

I was exhausted from huffing it out EARLY because the post office closed on Saturday at 1pm so when I got out and finally got the film/filter I was really exhausted and decided it was smart to for sleep for a whole, which was good since now I'm super sick and probably would be worse if I had stayed to shoot more.

Unfortunately after all that I only shot one roll and only some random landscape on the drive back to the airport just to have shot something....

This is what we call EPIC FAIL.

Thankfully I thought ahead and brought a few rolls on the plane so I still got some shots of the canyon just no IR shots... I guess this is an excuse for going back....

As Dan suggested I'm going to order some of the B&W developer I don't have and I ended up shooting a lot of Velvia/provia/ektachrome so I'll have to order an E-6 kit anyway.

A decent haul even for a failure...

It will be a well at least before I can get anything bought, but I'll post, thanks for the last minute help.

~Stone

Mamiya: 7 II, RZ67 Pro II / Canon: 1V, AE-1, 5DmkII / Kodak: No 1 Pocket Autographic, No 1A Pocket Autographic | Sent w/ iPhone using Tapatalk

3. Sorry to hear about the trip.... I've learned the hard way, to use FedX / UPS for shipments, I want on a specific time.

4. Originally Posted by Pfiltz
Sorry to hear about the trip.... I've learned the hard way, to use FedX / UPS for shipments, I want on a specific time.
And now so have I ... sadly not only did the shipment from myself arrive late so did the B&H filter sent from the store so now I have to call B&H to see if I can get my money back... lol uh... phone calls all day, the worst part about the trip isn't that it's over its dealing with all the paperwork and things that have happened since you left...

5. Well, the results are in, sort of... stand by for scanning, but from the looks of the negatives everything is very ... not exposed properly. As I mentioned somewhere else, the post office did NOT deliver my film on time and neither did they deliver the IR filter even if the film HAD arrived, so needless to say I've gotten \$40 in refunds from B&H and will attempt \$40 recovery on Monday or Tuesday from my local post office.

So I only had a chance to shoot some of the scenery on the side of the road driving back to the airport... I did as suggested and measured for EI6, Dev in HC-110, few minutes pre-wet. Will let you know in 20 minutes or so... but it looks "miss-exposed"

6. Either IR film is really super grainy, or HC-110 is not the Dev for me. I've pushed Tri-x 400 to 3200 and gotten WAY higher accutence, it's like a mucky mess. Maybe I'm pixel peeping too much, the overall "look" is pleasing, but even the slightest zoom and there's an obvious muddy appearance. Some certainly were over exposed, some only slightly enough that they scanned with no adjustment. Even the few images I didn't have to adjust pre-scan look muddy, the actual grain in the soft areas seems "fine" but nothing is sharp and the falloff from light to dark is just bleh... now Dan don't take this in any kind of insulting way AT ALL, I had NO experience with this film so I think taking your advice was a valuable choice and I really wouldn't have had anything if it weren't for you and the others who gave input. Seems as far as exposure, the most natural exposure was the one I took as a joke out of my car door at a gas station while my GF was filling the tank (yep that's how I roll haha, no seriously it was just her turn to pay, we were sharing in gas expenses), I used my in camera meter instead of the spot meter. Really motivated to get better imagery and I wish I had actually stopped and taken some conifers in the snow and some close up shots rather than mostly wide's, I was kind of in a hurry to catch the plane, just wanted to kill a roll in the wide open landscape.

I set the camera to IR "infinity" in most all shots and I think I had it at f/11 the whole time, so it just shouldn't be this mucky the whole way through.

I'll be posting 5 of the 10 in my gallery but here is an example of the mucky grain I mentioned, is this normal?

7. It's never a good idea to travel to a location and use materials (or equipment) with which you're not familiar. This is especially true if it's very different than what you usually use, as IR is. You would have been better served by shooting about 10-12 rolls prior to your trip.

8. oh and the car window one...

The actual "nice" images will be for the subscribers in my gallery

9. Originally Posted by eddie
It's never a good idea to travel to a location and use materials (or equipment) with which you're not familiar. This is especially true if it's very different than what you usually use, as IR is. You would have been better served by shooting about 10-12 rolls prior to your trip.
Well that was helpful thanks... considering I only have 9 rolls of the stuff and it costs a boat load, that's not really very helpful. This was a last minute decision and I'm not really worried about the exposure issues or how not nice the images are, it was a test run so I'm not worried about that, I just want to understand the grain issue, that and I promised I would post the results for the helpful people who gave insight into this unusual film...

10. OK, re-reading that, I sound like a dick, my apologies Eddie, that was a snap answer, sorry, you were only making your own suggestions that you felt would be helpful, thanks for the advice and I'll take it under consideration.

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