How will Ilford SFX 200 and Rollei Infrared 400 differ when used with a 720nm IR filter?
Asked 5/18/2018
5 views
2 answers
0
I’ve only used Ilford SFX 200 for infrared work and I’m trying to understand how it compares to Rollei Infrared 400 when both are shot behind a 720nm IR filter.
My understanding is that a 720nm filter blocks most shorter wavelengths. If SFX is sensitive to about 740nm while Rollei IR reaches roughly 820nm, does that mean SFX is recording a much narrower slice of the spectrum and Rollei IR a wider one?
In practical terms, what differences should show up in the negatives or prints? For example:
- brighter or more “glowing” foliage
- stronger skin smoothing in portraits
- darker eyes or deeper skies
- different exposure requirements
I’m especially wondering whether Rollei IR would tend to produce a stronger infrared effect and need less exposure because healthy leaves reflect strongly in the near-IR.
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
8y ago
2 Answers
3
A brief note on history of both films:
- Ilford SFX 200 has roots in law enforcement - it used to be fitted in traffic cameras, together with IR flash, to capture drivers of speeding cars.
- Rollei Infrared 400 has nothing to do with the famed brand of medium format cameras (it is produced by Maco of Germany, which acquired rights to Rollei brand after the company bankrupcy), but descends from Agfa Aviphot. It comes from a long and distinguished line of aerial surveillance films.
Both emulsions were optimized for surveillance, and using them for artistic purposes was a distant afterthought to their original makers.
I am personally a fan of Rollei, but I know some very fine photographers who have mastered the Ilford SFX.
In my humble opinion both emulsions are capable of very fine and in the end quite comparable results. Both are tricky though, requiring non standard exposure metering and negative development. My suggestion would therefore be to stick with the devil you know, and rather put your energy into tuning your process.
I am quite certain there is more to be gained by optimizing your process with your current brand (no matter which one it is) than by switching and starting anew.
Originally by user62463. Source · Licensed CC BY-SA 4.0
user62463
8y ago
0
Generated from our catalog & community — verify before relying on it.
Yes—using the same 720nm filter, Rollei Infrared 400 will generally show a stronger IR effect than Ilford SFX 200 because it remains sensitive farther into the near-infrared. In practice, that usually means brighter foliage/wood effect and potentially easier exposure at the same filter strength.
But the result is not just about the cutoff numbers. Film speed, contrast, filtration, lens hot spots, development, and the subject’s actual IR reflectance all matter. So don’t expect a simple “20nm vs 100nm” look calculation.
A useful way to think of it:
- SFX 200: extended-red film with a milder infrared look
- Rollei Infrared 400: more IR-sensitive film, typically capable of a more pronounced effect
Portrait and foliage differences can happen, but they depend heavily on scene and technique. If you want the classic dramatic IR look, Rollei IR is more likely to give it. If you want a subtler, easier-to-control effect, SFX is often preferred.
Both films were originally designed for surveillance/aerial uses, and both can produce excellent artistic results when matched to the look you want.
Recommended products
UniqueBot
AI8y ago
Your Answer
Related Questions
What exposure compensation should I use with Ilford SFX 200 and a Hoya R72 filter?
Why does a FOTGA variable IR/ND filter give weak or mostly red results on an unmodified Canon 7D Mark II?
Why aren’t green leaves turning white in my infrared photos?
What’s the difference between an infrared filter and an ND filter for photography?
Why can some cameras still shoot infrared without removing the internal IR-cut filter?