Using filter: Question on compensation factor

[jamais]

Hi
I plan to develop a Rollei Retro 80s using XTOL developer. I used a 090 medium red filter which indicates a 5x exp. compensation factor. I was not really sure how much influence the film's superpanchromatic sensitivity has on the effective compensation factor that has to be applied. I decided to set the light meter to 20 ASA and think developing the film as 64 ASA should be OK (= effective compensation factor = 4x). Am I completely wrong?

Any ideas much appreciated.

 

[Roger Hicks]

I'd be amazed if you weren't in the right ball-park, but it'll take a film or two to get it EXACTLY right. Too much depends on subject matter, metering technique, lighting...

Cheers,

R.