What exactly caused this...? Xtol & Tri-X

[daveozzz]

I shot a pile of Tri-X 400 exposed at 800 and have been working my way through developing it. The last roll I developed came out very differently to the rest - quite fine grain and extremely low contrast - which I kind of liked because was very easy to scan.
Previously they had been high contrast to the extent the highlights were almost blown.

The difference was, with the first lot I developed in 1:3 xtol (if I remember correctly) and a tad warm (22 degrees). The last lot (low contrast) was in xtol 1:1 at 19 degrees so a shorter development.

I used the MDC for dev times and adjusted for temperature according to the Ilford chart.

Which do you reckon caused the contast change? The temperature or the dilution?
(The rolls were all exposed the same).

 

[markinlondon]

Dave,

can't explain the contrast change, but the finer grain is to be expected due to the higher sulphite concentration at 1:1. How's the shadow detail, Tri-X @800 in Xtol is hardly a push at all? Was your agitation consistent throughout? If anything I would expect lower contrast from 1:3 due to local exhaustion. Kodak no longer recommend that dilution due to unpredictable failures. I know a lot of people still use it successfully though.

Mark

 

[gns]

Shorter development time will bring the highlights down, lowering contast (and minimize grain). But since dilution and temp are different, it might be hard to say for sure what is going on.
If you want to control the contrast, do some tests with the different times, but keep dilution and temp consistent.

Gary

 

[daveozzz]

What about the temperature difference then? Irrelevant?

Agitation was 4 inversions for the first 10secs of every min... each time the same.

One other thing I did do different the last time (low contrast) was to give my 5 litre container of xtol a swirl before using it. The times before I just picked it up and poured out of it... xtol's not inclined to"settle" if you know what I mean is it..?

I'd just like to know how to do this on purpose!

 

[daveozzz]

gns I'd say what you describe sounds like what I got. Dunno - maybe I didn't measure the xtol temp right and didn't develop as long as I meant to or something.
I've only ever developed 3 rolls of Tri-X so a *lot* more experimentation is needed!
Cheers.

 

[Todd.Hanz]

Are you sure your metering was the same, I rate Tri-X at 200 and develop 1:1 and get great shadow detail and lower contrast negs.

Todd

 

[daveozzz]

Yip. I incident metered with a hand held and kept the same exposure all night. It was dark outside and the lights never changed.

 

[pbjbike]

Definitely the !:3 dilution is the main case for the difference. 1:1 will give you greater contrast, all other factors being equal. To be a member of the LUG, you have to use XTOL 1:3, but we'll let you stay no matter what your dilution preference. 😉

 

[gns]

Daveozz,

Todd describes a good and well known solution for dealing with high contrast situations (like 5th avenue in bright sunlight). Rate your TriX at 200 (or even 100) to make sure you get shadow detail, and cut dev. time by 30% or so to keep highlights under control. You can up contrast later if needed, but you cannot add detail where it does not exist. Sort of a poor man's zone system approach.

Gary