Rollei infrared developing suggestions

[Cabledog]

Anyone developed rollei infrared film? I developed a test roll at ei 12 and 25 with an R72 filter. I'm using replenished Xtol. The massive dev chart only has ei50 so my question is if I'm shooting at ei 12 or 25, would my development time be less or more than at ei50? Thanks!

 

[charjohncarter]

I know this isn't what you want but you might be able to get something close by extrapolating with the Massive Chart.

I do Efke 820IR at 14 minutes, 68 degrees, normal agitation, HC-110h. I also shoot a one half of the normal speed for an R72 filter. This is very slow at 1 EI: f16 @ 1 second.

 

[Moto-Uno]

You would develop it for less time . If, for instance you could get some HC-110 , you'd find the chart gives times for ISO 12 and ISO 6 . I didn't have much luck trying to get that IR glow at ISO 12 with the same filter . It was suggested to try ISO 6 . I then bought an R820 filter and thought using an ISO 6 exposure would get me the goods (so to speak) .
Let's just say that wasn't so well thought out . Further inspection showed that the R820 filter passes significantly less light and left only traces of any exposure on the negative.
You live and if you're lucky , you learn ! Peter