Rollei IR 400 development timings

[Noemifil]

Hi! I am currently shooting on Rollei IR 400 (120mm) using a standard red filter (3 stops) in order to get both visible and infrared light. I am metering the light considering the 3 stops of the filter, so the exposure is already correct before the processing. I am developing using Xtol (1+1), but I found contradictory timings online and on the film box. On the box says 17min, but online I found 7min 30 sec (pre soaking the film in water for 5min). I shot 2 rolls and developed the first for 7 and half minutes, which came out nicely but needed a little "push". I tried 8min for the second and the mid-tones were awesome. What is you experience with this film? Has anyone tried to develop it for 17 min as Rollei suggest?

 

[Andrew O'Neill]

I use this film often but develop it in Pyrocat-HD 1+1+50. I almost always use it with a 72 filter. My normal time is 7:00 @ 21C. I've generated my own data as I usually do with a film. If 8 minutes works for you, then that is great.

 

[Andrew O'Neill]

...and I should add that I only use sheet film version, continuous agitation in BTZS tubes...