Metering for Rollei IR400 using the R72 Filter

[Inayat Noor]

I started using Rollei IR400 and am seeking metering advice.

Current advice is to set the ASA on 6 - 12. I always use my Pentax spotmeter through the filter and take a reading per the film speed, ie 400.

So, do I set the meter on 400 and meter through the filter?
Or, do I just set the meter at 10 and use that result?

Thanks

Jim

[John Olsen]

I started using Rollei IR400 and am seeking metering advice.

Current advice is to set the ASA on 6 - 12. I always use my Pentax spotmeter through the filter and take a reading per the film speed, ie 400.

So, do I set the meter on 400 and meter through the filter?
Or, do I just set the meter at 10 and use that result?

Thanks

Jim

Don't meter through the filter, just set the ISO at 6-12. At least, that works for me. (I use a Pentax Spotmeter also.) ISO 6 seems to wok better for HC110 "B" development, whereas ISO 12 works for Rodinal.

[Inayat Noor]

Thanks John, I use D76, so I'll use the big digital chart for times/agitation. I'll set my meter at 6.

[paulbarden]

No, do NOT meter through the filter. Meter at around 6 ASA (or wherever you feel comfortable as a starting point) without the filter.

[Sandro]

As previously stated by other users, meter normally, set the iso to 6-12 depending on developer, and don’t forget the IR72 filter!
If you use a stronger filter, iso could be lower.
If you take an average metering, consider you will get very light green foliage, and dark/black sky.
Foliage effect depends a lot on, well, the trees. Light green foliage have a stronger effect.
I measure the light green foliage and add 1 stop to avoid getting them white, but your preference could be different.

Welcome to the IR photography!

[Andrew O'Neill]

When using the 72 filter, I set my metre at EI of 3. I never metre through the filter.

[agregov]

I've had good success using a IR 092 filter (4 stops). I believe the R72 is 5 stops. So, far I've been shooting with a Leica M7 and simply screw on the 092 and meter through the camera. Works excellent. I probably wouldn’t meter through a spot meter but you could try it and compare to adjusting exposure manually. Note, I rate the film at 200asa. So, my effective speed is 12asa. I'd go to 6 or 3 with an R72.

[jim10219]

I would say iso 6-12 with an R72 is a good place to start. But I always bracket IR film if the shot is important. The amount of infrared light isn't directly proportional to the amount of visible light. So, since what your meter sees is just the visible light and what your film sees behind the filter is pretty much just the infrared light there remains the possibility for your readings to not line up with your results. And without a good way to accurately measure the infrared light (that you meter likely wouldn't read correctly even if you did put the filter in front of it), the best you can do is take an educated guess. Therefore, if the shot is important to you, it's probably a good idea to bracket, especially in the beginning while you're getting to know the film. Eventually you'll figure out when you can trust the film, like at noon on a sunny day, and when you can't, like at night under street lights.

There are a lot of interesting uses for IR film other than just the wood effect. For instance, IR film cuts through atmospheric haze extremely well. So it can make mountains in a distance pop that would otherwise look very soft and low contrast.

[murr]

Be brave: meter trough the filter and without it and compare the results.

[Jim Andrada]

I haven't used IR film in ages, but I remember that I didn't meter through a filter since the spectral response of the meter element is almost certainly not exactly the same as the film.