Q about agitation

[btgc]

Wanted to ask if 1+1 is 2 all the time or sometimes it's 1 or 3. I did my first 2 stop push development (LegacyPro 400@1600, LC29 1+29 20C for 18minutes). Tank I use is with twirl knob.

Like for Neopan400 I slowly twirled for first minute, then 3-4 sec. each minute. After 10 mintes, that is, for last 8 minutes, I twirled knob each 30 seconds, just shorter, about 1 slow turn instead of 2-3 as up 10th minute. Don't ask me why I did so, I had strong feeling I have to, and took notes as usually.

So my question is did I get about same results as little longer twirls would do, but once per minute?

 

[Chris101]

It's hard to tell from your description exactly what you did, as I agitate by inversion (3 inversions per 5 seconds.) I agitate exactly the same way when pushing, which I do by extending the time of development only. So to repeat, I do not change the agitation when pushing.

I think that is an answer to your question.

 

[charjohncarter]

Everybody has to find their own total process: development time, developer brand, EI of the film speed, film, agitation, dilution, temperature, metering technique, etc. The main thing is to only change one variable at a time, and keep all the others constant; you will never get any sensible results if you change too many (or just two) of the variables at one time.

Most of these variables are not as critical as you think, but you have to be consistent. We have all done the opposite, but try to be, well sensible.

 

[btgc]

Basically, I should have asked more clearly - do 2 inversions each 30 seconds result in same as 4 inversions each minute?

I agree about consistency, same as with performance tuning - change two factors at a time and who knows which one did the change...or both.

 

[Roger Hicks]

Basically, I should have asked more clearly - do 2 inversions each 30 seconds result in same as 4 inversions each minute?

I agree about consistency, same as with performance tuning - change two factors at a time and who knows which one did the change...or both.

Not exactly, but the difference is far smaller than some people would have you believe, especially on a 10-minute developing time. Two inversions every 30 seconds probably equates to slightly more agitation than 4 inversions every minute, and you might see a slight difference (more toe speed, slightly more contrast) at a 5-min dev time -- or you might not.

Cheers,

R.

 

[ChrisN]

I just hung a roll to dry, dev'd with two inversions every minute as opposed to my usual four inversions. Looks identical at this stage.

 

[sepiareverb]

When pushing I cut back on the agitation for the additional time of the development. Has always worked for me.

 

[btgc]

Thanks all. I see it's kind of a magic, what to say. I were worried if generic suggestion for pushing (x2.25) taken from MDC will be enough to develop film undexposed by two stops so I felt urge to add a bit of agitation. For first time it were quite OK to my eye.