Dev times: roll film in tanks to tubes

Possibly a silly question!

I have finally bitten the bullet and am about to start shooting LF film in my ebony rsw45 rather than shooting 6x7 with a roll film back all the time.

I have my dev time for 120 acros in pyrocat HD pretty well sorted - how should I adjust it for 4x5 in tubes?

What type of tubes do you mean, e.g Jobo vs. BTZS?

In any case, I suggest that you purchase the film testing service at The View Camera Store (they advertize on APUG) which costs $45. It will save you money in the end and will give you a wealth of information, even if you do not strictly follow BTZS methods.

Good Morning, M Liddell,

Generally speaking, manufacturers of sheet film give recommended times for small tank or continuous agitation. Continuous agitation times are typically shorter of course. I don't use pyrocat HD, but I suspect that reducing development time for about the same percentage as that recommended for other developers should give you a good starting point.

Konical

Tubes are the usual BTZS with no jobo involved. Since I'm in the UK I think I'll just have to burn some film testing using my spot meter to read the density difference above b+f. Thanks guys.

I am also working with 120 roll and 4x5 FP4, the sheets done in tubes, like BTZS but home made with black ABS tubing. Your agitation method with the tube, whether constant, or some form of stand, whatever, will likely differ from you roll film tank method, as mine does.
I think you just need to test and find the right combo.