Multiple film types in same processing batch

[robert_cardon]

I�m seeking your collective wisdom on a seemingly obvious answer film

development question because my local expert, a veritable walking

encyclopedia of photo knowledge, was unavailable when I mulled it

over.

 

I�ve read this forum for a year and have noted all the different

development and film combination possibilities available, and how

devoted folks are to their favorite mix. Thus I�m contemplating

expanding my B&W film options after reading how many of you

successfully exploit the unique characteristics of the various films

and developers available. To date I�ve shot only FP4 and HP5, but

wonder what I could be �missing� when it comes to different emulsions

and development procedures.

 

If I start using other films in addition to FP4 and HP5, trying to

standardize a development regime for all films I shoot would be

tempting. Since time (and chemistry) is at a premium, ideally one

could run several different emulsions in the same Jobo batch. Let�s

say I do tests to determine each film type�s EI to achieve adequate

zone III shadow detail given a *** standard *** development regime

(for the sake of discussion, assume no contrast altering procedures

are intended, no N-1 or N+1). For example, let�s to achieve the

proper shadow detail at 8 minutes in D-76 1:1, I rate FP4 at 80, HP5

at 180, and Tri-X at 100. My questions are: 1) What are the

downsides for doing this; and 2) have any of you tried to establish

exposure or development strategies to allow processing different film

types in the same batch and come up with satisfactory negs for all?

 

I would assume that if you rate and process your films as I suggest

above, you are in effect pushing or pulling at least some them in a

multiple-film-type-per-batch-run.

But it seems that for emulsions with the same �true� speeds (versus

stated film speed), e.g., FP4 and Plus-X in the same batch, that an

acceptable compromise development and EI for each film could be used

to obtain good negs all in the same batch.

 

Any insight on this matter would be appreciated.

 

THX in advance

 

Robert

[bruce_barlow]

I think life's too short to be frugal in the way you seem to want to be. If I'm going to spend all that time in the field making negatives, I want to make sure I process them to maximize their potential. I want to know the true film speed and development time to make the most of each one. I haven't found development times to be the same for different kinds of film, and since I tray develop I can't really combine them. Are they acceptable if I put them together? Yeah, maybe, since the times are only about 30 seconds different, and I can pull out those with longer development times sooner and they'll just be a little flat. But I think it's bad for my head. So I keep exposed film in old boxes until I have enough to make a batch worthwhile (6 minimum, unless I'm using PMK, then it's 4). I even bought some boxes of 25 sheets (rather than the usual 100) just to get small boxes for storing exposed film...

 

Doing any less does a disservice to the guy in the field (me!). We gotta be tough on ourselves and only let ourselves get away with doing the best that we can!!

 

Good luck. I just got a decent stereo for the darkroom, which makes all those minutes in the dark much more pleasant.

[Troll]

Consider using DIAFINE. All films are developed the same time and temperature. The stuff lasts forever, and is very forgiving, with extremely sharp details and nice grain.

[david_karp]

I second the use of Diafine, but do your own speed tests. I find that my film speed is lower than those suggested on the Diafine box. Diafine is a 2 bath developer. The A bath has the developer in it, with little or no activator. The activator is in the B bath. No stop or rinse in between. It is also a compensating type developer. The developer that soaks into the film is depleted more rapidly in the highlight areas. When it is exhausted, development stops. There is less silver to reduce in the shadows, so development continues after the highlight development is complete.

 

There are other 2 baths that allow you to develop different films together for the same time. Barry Thornton developed a 2 bath that works nicely with sheet film. A bath: 750 ml distilled water, 6.5g metol, 80g sodium sulfite, water to 1L. Bath B: 750 ml distilled water, 12g sodium metaborate. You can increase the sodium metaborate to 20g for plus development (it works). Another trick for plus development is to intensify the negative in selenium toner diluted 1:1. Time is 5 minutes in each bath for sheet film. 4 minutes for roll film. Here is a good discussion by Thornton: http://www.barry-thornton.co.uk/2bath.htm. Note that the formula changed in his book a bit from this web article. He e-mailed me that the version in the book is the most current. Adams also discusses 2 baths in his book "The Negative."

 

I don't think you will be disappointed with your negatives developed in either developer.

[aaron_van_de_sande]

Try developing by inspection.

[scott_walton2]

Your choice of films perfectly matchs Diafine. I have used it for years and with

"standard films" (read non t-grained film) you can process all together. I find,

for my system, I use the film at speed and have perfect negatives for my cold

lights. You might also want to consider Divided D76 also! I have a copy of the

recipe but you can also get it from Photo Formulary. DD76 isn't as sharp albeit

a extremely fine grain formula but Diafine is a high acutance developer

making your grain edges sharper giving the illusion of sharper prints. Highly

recomend both soups!

[dk_thompson]

Well, you could get a copy of Pub Z-133E (Kodak) "Monitoring & Troubleshooting Black and White Processes" and a box of control strips (and a densitometer) and establish some batch times for those film types.....or you could just run your own "eyeball" experiments however you wanted to and figure out good times that are either a compromise acceptable to you, or maybe they'll work out just right. fwiw, I run a deeptank line where I work with TMAX RS and find that I can run just about any modern film type through it with just one or two times. Usually 7 minutes at 75 degrees for the t-grain stuff, and 5 min. for the trad. emulsions. I do some slight push & pull times for ortho films and different types ogf contrast ranges, but for everyday stuff and studio work, these times give us really good, consistent negs--so much so, that I run a smaller 1 gallon tankline in my own darkroom (replenished too) and use about the same times. I shoot alot of Tri-X, HP5+, FP4, TMX, and TMY. The HP5, TX, FP4 goes for 5 minutes. The TMX/TMY is run for 7 each, and I shoot Delta 3200 at 800EI for 7 minutes. All times are for 75 degrees and I use liftrods with steel reels, and baskets with sheet film hangers. I process in the dark, by hand....if you run enough film, replenishment is a good way to go, if you can keep accurate logs and pay attention to process control....btw, this is the way most commercial labs run b&w film--all at one time--aiming down the middle or hopefully for the best contrast index and film speed. The control strip made by Kodak is based on TMY, and you apply factors to it for different film types.

 

Might not be the best answer, but it's a different way of doing it and it works.

[michael_kadillak6]

The short cut expected is not proportional to the expected results. Each film will react differently with the chemistry in the drum. Unless you expect to continue to load the same film in the drum each time you process, the results you will get with a drum of just brand X versus will vary and frustrate you.

 

Kodak's new coating machine is supposed to take the variability of emulsion thinknesses out of the equation that previously necessated buying lots of the same manufacturer to maintain consistency.

 

Sexton stated a while back that when he processed in Jobo, he tried for a full drum of film but used exposed blank film to compensate for normally exposed film as 1 sheet exposed blank to two sheets of photograph exposed film to make up a drum. Consistency os the key.

 

Lastly, if you are not dissatisified with your Ilford results, why change? I find that the over emphasis of energy and time spent on materials is not where the answer is at. I will take a great image on even average materials any day of the week.

[henry_a]

I can run FP4 and Delta 100 in Xtol 1:3 together and get OK results but why would I want to do that? If I'm carting around a big camera its because I want GREAT image quality so I'll give the film I use the best combination of technique, time and developer I can. In the case of the two films the FP4 wants a bit more time than Delta so I give it what it wants. If I want more convenience I'll use roll film in a smaller camera. Granted films do look different but not so different that I'd need to carry everything made. I say pick a slow film and a fast film and be done with it - or maybe just one film! Not that you shouldn't experiment at all, but adding more films to your work may cause confusion and maybe create a bunch of OK negatives, not necessarily GREAT negatives. The simpler you make it the higher the number of GREAT negatives you'll get.