Kodak Plus X film speed

[ymc226]

Does this seem right. I followed Ansel Adam's instructions in his Negative book for determining film speed.

Plus X in HC 110 5 minutes with EI 250, a full stop faster.

For Fomapan 200 in HC110 3.5 minutes I got an EI of 160 which seems more plausible.

 

[Ronald Moravec]

All the shutter speeds, meters, and f stops need to be calibrated for you to say 250 is the real speed.

Feel free to use 250 if that is the tolerence stack up with your equipment, but call it EI not ISO.

 

[DWThomas]

You don't give any much detail here as to dilution and temperature. I've only gently scratched at the edges of this personal exposure index business, but the Kodak sheet for Plus X suggests 3 1/2 minutes in HC110 Dilution B at 20ºC for a small tank, so I'd think 5 minutes could approach a stop of pushing? I've ended up going with HC110 1+63 to avoid those ultra short times when I use it -- too hard to time accurately.

DaveT

 

[Harry Lime]

Hmmmm, not sure that is right. I've always guessed (and read) it to be more around 75-100asa...

But of course I could be wrong.
;-)


HL

 

[htmlguru4242]

Interesting, I've done no formal tests, but throughout my experimentation with it, in D-76 1+1, EI 100 is dead-on.

 

[Nicholas Lindan]

Does this seem right. I followed Ansel Adam's instructions in his Negative book for determining film speed.
Plus X in HC 110 5 minutes with EI 250.

Sound right? No. It sounds like you are going for higher contrast - "N+1" in AdamSpeak.

Five minute and under developing times with hand developing can be problematic: minor variations in agitation, pour in/out speeds, tank and reel type etc. etc. can make significant differences in the results.

Try something a bit slower and more foregiving for a developer: D-76 1:1 used 1-shot is a very stable process around which to base your tests.

I find when my "EI" doesn't agree with Kodak's it is because I am doing something wrong. Rather than change EI I change technique.

 

[Gerald Koch]

So many people ask about help with film speed. Unless you have the testing facilities of Kodak you really can't determine someone else's speed. There are simply too many variables and personal preferences involved.

Really, isn't this the purpose of the box speed. Film manufacturers spend a considerable amount of money to publish speeds for the average user with the average scene. If you are getting something wildly different then you are doing something wrong. I'm always suspicious when someone is adamant that Tri-X should be exposed at 64 or 1600.