After reading an article on Emulsive about Fomapan 400's spectral sensitivity going into the near IR realm, and seeing some of the results posted there, I decided for June's roll to put my cheap 52mm R72 filter on the front of my lens and shoot the roll. The EZ400 film I've been using is commonly known to be re-badged Foma 400, so I thought this would be a no-brainer. If you’ve spent any time reading my blogposts, you’ll know that I shoot a lot of IR, mostly in digital but some recently on Rollei IR 400 with my Rolleiflex 3.5E . So this isn't new territory for me, or at least it shouldn't be.

I set out last weekend on a bright sunny Sunday, and shot the entire roll at a few different locations. I rated it at ISO 1.5 with the R72 filter on, and zone-focused @f/16 to help alleviate the focus difference between normal and IR light. Afterwards, I finished the last 6 shots left on the roll with no filter as normal 250 ISO B&W film, then developed the roll in Rodinal 1+25 @ 20C.

I thought it was a gamble on whether or not it would work, with the outcome being 1 of 2 possibilities.

1. FAILURE - No images at all, if the film wasn't really sensitive at or near 700-720nm, because the R72 filter blocks everything below that.

2. SUCCESS - IR images with white foliage and black skies - the typical IR look.

What I ended up with was somewhere weirdly in-between.

The skies are black-ish, but there is little to no Wood effect in the foliage. I assumed that the filter works as it should, because I had shot with it the prior week with Rollei IR 400 and it worked like a champ. This result was completely unpredicted, and I'm not certain how it happened.

It doesn't make much sense to me.

Looking on Foma’s website, their data sheet for Foma 400 shows the cut-off just below 700nm, maybe around 695nm. So in theory, people who have had good results with the film using R72 filters should not have had any results – just a blank negative. If one assumes the R72 filter doesn’t let ANY light in below 720nm.

More digging.

The cheap “R72” filter that I purchased on Amazon may not really be a true IR filter. I read a few reviews where the users have used it with digital cameras that still have their IR filter on the sensor and they can’t get the white foliage Wood effect with it, and have stated that they think its just a deep red filter like a 25A plus some ND coating.

I also read where people have had success with Rollei IR 400 with just deep red filters.

So, I think the bottom line is that my cheap “R72” filter allowed me to just “get-by” with the Rollei IR 400 film, but because it’s not really an IR filter and probably lets light in that sits in the normal spectrum, it allowed for images on my recent negatives that didn’t have any white foliage.

Would a true R72 filter get results with the Fomapan/EZ 400? I guess if I want to find out, I’ll have to bite the bullet and buy a Hoya or some other real R72 filter and try out my theory. We’ll see.

At least I managed to get some images in spite of myself. I also shot a 3-image pano that I’ve been wanting to do for a while. So there’s that.

Stay away from cheap R72 filters kids. They’ll rot your brain.

Thanks for reading.

Jeremy