Problem: Repeated overdevelopment with Kentmere 100 in Flic Black White and Green at published time/temperature/dilution

[Premier]

Hello all,

I am having a problem that I think is not due to typical user error. I have been using Flic Film's Black White and Green film developer for about six months, mainly with Kentmere 400 at published dilution (1:49) and times (both from Flic's documents and the Massive Development Chart of 16min 15 seconds with good/expectable results of a straightline showing a nearly .65 gamma. I recently started shooting and developing Kentmere 100, shooting it at box speed, and using the corresponding dilution and times published by both Flic and the MDC, 13 minutes and 30 seconds at dilution 1:49. The stouffer's tests I have been doing have both show a nearly 1.0 gamma, and negatives that I have found way too contrasty to reliably print the highlights from. I have tried to reduce agitation from a 1 minute initial agitation scheme and 5 seconds every 30 seconds down to a 30 second initial agitation and 5 seconds per minute. I have closely monitored the temperature and dilution, wondering if I had messed something up there. I was at the bottom of a bottle of Flic BWG developer and opened a new bottle, after having read someone else having a similar experience with Kentmere 100 and a different developer (HC110?).

I am still aware that it may be my error, and hope that some of you may be able to identify a problem either in my description or assessment of the testing. I am attaching the scans of the most recent Stouffer step wedge and the chart I made using a Macbeth 500, which gives readings more reliably than, but still close to those of an X-rite 331 transmission densitometer.

Is it possible that the published times by both Flic and the MDC may be in error?

I am considering changing to a different developer. Ideally I should be able to adjust my time and/or dilution to get better development with this developer, right? What can anyone suggest as starting/adjustment times/dilutions? I have considered semi-stand development, but don't want the problem of bromide drag that seems to come with it. Is there a highly recommended developer for Kentmere 100? Has anyone else encountered the same problem with this film developer combination?

I have included scans of the stepwedge, H&D chart, and shot exposed using a Pentax 67ii set at box speed, for illustration.

Thanks for all of your comments, in advance!

 

[thinkbrown]

Is it possible that the published times by both Flic and the MDC may be in error?

Sounds like you've determined it is for your setup. If the contrast is too high I'd reduce your development time.

IIRC black white and green usually has similar developing time to d76 1+1, which Ilford calls out as an 11:30 developing time for kentmere 100, so that's probably where I'd start.

 

[Andrew O'Neill]

I probably don't need to tell you this but, make a few more exposures of your step wedge. Develop them at different times. Makes curves. Graph the data to determine your N times.

 

[Premier]

I probably don't need to tell you this

Thanks, as your gentle suggestion goes a long way! It will be my first attempt at experimenting with alternative times.

 

[Premier]

IIRC black white and green usually has similar developing time to d76 1+1, which Ilford calls out as an 11:30 developing time for kentmere 100, so that's probably where I'd start.

Thanks, this is also a helpful suggestion.

 

[MattKing]

Is it possible that the published times by both Flic and the MDC may be in error?

Absolutely!
Particularly the MDC.
However, I would hazard a guess that you may have already applied as much or maybe even more rigour in your testing methodology then Flic Film have available to them!
A lot of the "data" floating around the industry and the internet is very anecdotal.

 

[retina_restoration]

I tend to avoid using the times published on the MDC as I have found many wildly inaccurate times listed for some film/developer combinations. I wish it was more reliable.

 

[MattKing]

The biggest challenge with the MDC is that information on it comes from all sorts of sources.
There is no reliable way to tell if a submission came from someone who prefers negatives like the ones that @Premier finds problematic - as I would.

 

[oneeyedpainter]

The biggest challenge with the MDC is that information on it comes from all sorts of sources.
There is no reliable way to tell if a submission came from someone who prefers negatives like the ones that @Premier finds problematic - as I would.

I think MDC would be much more useful if the entries included at least a note about typical negative usage (e.g., silver print vs scanning vs alt-processes). We cannot ask contributors to report the actual densitometry results, but typical usage would already be a helpful indication.

 

[tcolgate]

I think MDC would be much more useful if the entries included at least a note about typical negative usage (e.g., silver print vs scanning vs alt-processes). We cannot ask contributors to report the actual densitometry results, but typical usage would already be a helpful indication.

Some entries do mention it on a note, but it's very rare. (I've seend it on some of the pyrocat entries where it'll say it's suitable for a palladium print). I just assume they are a very vague starting point now.

 

[MattKing]

In some rare cases, there are notes that do help - e.g. details about development to X gamma.
But as the sources for the information are rarely identified ......
I consider the MDC most valuable as a source for info about what experiments people have tried with unusual film-developer combinations.

 

[P C Headland]

13.5 minutes feels a bit long.

I use the home brew version of BW&G, PC-TEA for many films. I'd start at 1+50 for 11 minutes at 20C. I do 15s inversions (6-8 inversions) for the first three minutes, then two gentle inversions every minute there after.

If it's a new-to-me film, I'll cross-check against a time thats an average of the D76 1+1 and Xtol 1+1 times.

(This is for scanning.)