Efke 50 sheet film, HC110, Jobo Drum

Hi all,

I have just bought one pack of Efke 50 (4x5) sheet film, and have done
some tests. The result is strange for me.

ND (@ISO25): 6min, HC110 1:99 (Yes, 1:99) in Jobo 2840
paper drum, approx 10 rpm hand rotation (@20 DegC)

N+1 (@ISO40): 11min, HC110 1:99 (@20 DegC)

Anyone got any similar result ??

Thanks, Jack

I take it you mean you are getting N(ormal) at 6 min and N+1 at 11 min. The N+1 sounds a bit long, but this could be due to the high dilution and that the developer is starting to give up (oxidize) after reaching normal. How much developer do you use/per sheet? (A common problem with e.g. Rodinal at 1:100, where people forget to use a larger drum to accomodate the 1/2 liter of developer/roll needed.)
If you have tested other films with that diluted developer, what is your result there? Similar or is N+1 only some 20-25% more than N.

//Björn

For 4x5 sheet film, I put at least 3ml of HC110 (ends up with 300ml), and for 8x10 sheet film, I use 6ml (ends up with 600ml).

The weird thing is that, the dev. time from Efke, it states something like HC110 (B) 7 min (??) @ ISO50.
I have no idea how this film could dev under (B) and jobo drum.
I will shot some film and see the actual result in coming week.