Testing film + developer in 35mm, for both 35mm and 120??

As I get back into the swing of things with B&W film development, I am looking at ways to keep the number of variables to a minimum. With this in mind, I decided to choose just one film, which is available to me in both 35mm and 120 film sizes, and one developer.

I have been wandering through the many posts here, and am interested in the possibilities of using one of my old favorites - HC110 - at higher dilutions, for longer times, with reduced agitation. I had planned to use HC110 at 1/2 dilution "B", which I understand to be referred to as "unofficial" dilution "H".

I have also seen a fair number of examples of photographs using TMax 100 which remind me, at least generally, of what I used to like about Plus-X (in D76 1+1 if I recall correctly), but with reduced grain. I have tried a couple of rolls, with a couple of different approaches to development, and I like the possibilities.

With all this in mind, I have assigned myself a project - develop some new protocols for myself for exposure and development, using TMax 100 and HC110 (dil H).

I have TMax 100 in 120 rolls, and in bulk 35mm. I plan to do my initial testing in 35mm, so as to take advantage of the greater flexibility that bulk loads provide, plus a number of other practical benefits. In the interests of repeatability, I will use my hand meter, rather than my in camera meters.

Although somewhat out of practice, I have a reasonably well developed ability to read a negative and guage its "printability". As I have limited access to printing facilities, I hope to be able to get my times and techniques within the ballpark first, and then fine tune them by printing and then evaluating the prints.

Here is my question. Is it likely that I will be able to use the results of my 35mm testing for the 120 film and cameras, or should I treat the MF film as entirely separate, and start right from scratch with my tests with it?

I look forward to your thoughts.

I think the 35mm results will put you in the ballpark for the 120, but the 120 will probably need fine-tuning due to the other variables involved (from camera exposure thru development technique to enlarging methods) For example, different cameras most likely (unless your using a 35mm back on a MF camera!), you'll probably use a different enlarger lens for each, and development will be done on different reels. Depends on how picky you are... of the films I use in both these formats, I do use the same times, however I've never analysed if they print comparably.

I very recently was given a Bronica SQB to use. I didn't know what development to give the negatives as the last time I used 120 film was with FP4/FP5. These days I use FP4+ a lot, so I used my 35mm bulk loaded FP4+ times as a guide.

I found the times to be extremely close for full development. I also use a hand held meter.

I think you will get a close figure from your first 120 roll, using the 35mm film results.

Mick.

I know that there are some advantages of having a combo you are good with but I find that different films do better in different situations. I like TRI-X for scenes with huge SBR for its compressability and its ability to save the shadows and not block up the highlights. Pyrocat enables this quality. If I am shooting a flatly lit scene, I find FP4 of APX100 to be much better. If I need greater film speed, TMY has nice grain even if pushed - especially if developed in XTOL. This combo has wonderful tonality and crisp accutance. I would not head into the field with one film - I would not head into the darkroom with one developer. I use at least 3 - more often 4 combinations. For sheet film it is simpler.

Since you are establishing your own times, instead of using dilution H just dilute the HC-110 1:50 and your volumes will be easier.

It's never a good idea to assume that just because two film formats have the same name that they are the same emulsion. For example, Plus-X 35mm and 120 format are not the same film.

I work with HC-110 and use it at dilutions of 1:100 with 35mm Tri-X. On my first roll of 120 HP5+, I had no idea what timings to use with HC-110 (water temperature here is around 27DC) and decided to use my 35mm Tri-X timings, since I read somewhere that Tri-X and HP5+ were similar in formulation (I have no idea if this is really true.).

The HP5+ turned out beautiful. Conclusion: it is possible, but don't risk a particularly valuable roll of film on it?

There was actually a similar thread on PN recently:

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00Dxuu

There are differences in film _bases_ which can account for needing slightly diferent times. However, as others have said, there's no reason you couldn't use your 135 times as a starting point for your 120 ones. That's what I did. BTW, I have found I need to add maybe 10-15% to my 135 dev times to get the contrast I want with 120.

Also, I think it's just fine to go with a single film/dev combo for now. You can always add later.

allan

I have found that 120 Tri-X and Delta 400 need radically more development than 35mm - they're not even close. Tri-X needs about 50% longer time, D400 up to 100%. This is for a sulfite-rich ascorbic acid developer similar to Xtol. I have no explanation for this. They should have the same emulsion in both formats but act as if they don't.

I can only recommend you to do test strips with 120 before developing anything important.

Depends on the film/developer combination, but usually you should be pretty close, as long as the emulsions are really the same across formats.

One potential issue that might account for some variation, if you're using daylight tanks, is that with 120 you've got twice the volume of solution for the same area of film as a 35mm roll.

Thanks everyone for these useful replies.

I am certainly not adverse to trying other combinations, but I thought it would be useful to step back first and systemize (re-systemize?) my approach. I figured that if I could get the results I wanted from procedures standardized in the one format, that it would ease the setup of procedures in the other, but it is helpful to have your outlook on the issue.

One of the reasons that I considered the issue, is that I understand that the 35mm and 120 versions of TMax 100 are very similar. I did realize that the two versions of Plus X are quite different.

I have used steel reels and small tanks for 35mm since the 1970s. I am struggling with the steel reels for 120, but practice seems to be helping. I intend to persevere, in the interests of consistency and efficiency, and because I understand that if I have to go back to my previous system (Kodak Developing Aprons for 120, in tanks designed for steel reels), the 35mm to 120 equivalencies may be thrown way out of whack.

Out of curiosity, does anyone else here still use the Kodak Developing Aprons?

Thanks again,

Matt

I'd be surprised if anyone does, but I think Freestyle sells a similar product, manufactured in Spain.

David A. Goldfarb said:

I'd be surprised if anyone does, but I think Freestyle sells a similar product, manufactured in Spain.

Click to expand...

Thanks David - I would never have thought to look for a new product.

Now I just have to resist the temptation to backslide.

I have always been able to use the 35mm steel reels, because you can, in essence, load film on them with one dexterous hand. The 120 steel reels require more of an interplay between two hands, and are therefore very hard for me to use, because I have limited dexterity and range of motion in my right hand. It is basically impossible for me, for instance, to actuate the clip that is designed to hold one end of the film at the core - I have to position the end of the film just right, so the slot in the core of the reel provides just enough friction and resistance to allow the film to feed on to the spiral, without pulling out of the reel.

I am practicing though, and things are improving.

Matt