Plus-X vs. Tri-X for larger prints (16x20 or 20x24).

Oops, I meant *NOT* wasting my time or money. I'm already on the ramen-7-days-a-week diet. =)

I think that plus-X is an old and poor choice if image quality at that iso is your goal....Fuji Across seems to be the pick as the current 100 iso conventional B&W film....cheers, Bob

Choose a film because it fits your vision, the conditions that you must face when shooting or you are very familiar with it. If you want finer grain, use a larger film. Sure a slower film will give you less grain, but there are other considerations, such as using a larger aperture and/or a slower shutter speed, which in turn, may cause the image to be less sharp.
Keep in mind that a 4x5 print is viewed from a distance of about 18 inches, maybe less. A 16x20 or 20x24 print will be viewed from a distance of several yards. The amount of apparent grain at that distance will not be very different as you would see from a smaller print at a closer distance. What you will see is sharpness -- that is, a larger print will show deficiencies in sharpness more than smaller prints, so using a smaller stop and/or higher shutter speed when making a larger print is much more important than seeing grain. Moreover, there are more differences between films than just grain. Grain is only one aspect. The others, equally or more important, are ease of processing to your tastes, its tonal scale, its H&D curve and, well, you get the idea. Grain is simply the most apparent, but not, by far, the most important.
Since you say that your funds are limited, then I assume you are shooting 35mm. If that is the case, then I may also assume that a good number of your images will be done with the camera hand held. If that is so, then you would need the highest shutter speed possible while closing down the lens so that it can perform at its optimal. Since you are doing documentary photography, additional lights may not be possible. Thus, you would need the highest speed film possible. If all those assumptions are correct, then Tri-X may be the best choice, especially if that is the film that is most familiar to you. Do not worry about grain. Worry about the image. But if grain is still a consideration, then use a larger camera.
I hope this helps and good luck with your project.

Stick with the films you're familiar with. There's nothing wrong with Plus-X and Tri-X. Technique matters more than the film stock.

The trick to maximizing your negatives for very large, high quality prints is to minimize grain and control contrast. That starts with the exposure and ends with development. It's the old cliche: expose for the shadows, develop for the highlights. But too often the rationale and practical technique are glossed over.

Whatever the ISO rating, cut back a bit. For example, Tri-X or HP5+ at EI 200-320, developed in ID-11, D76 or almost any developer for the appropriate amount of time will yield much finer grain and better tonal range for easier printing.

Many folks (especially students) tend to underexpose their negatives and compensate with overdevelopment. This used to be called push processing. Now a lot of photographers new to b&w film photography approach it as standard practice rather than an exception, a special technique to be used only when needed or desired. And with some films, shooting at the rated ISO and developing according to manufacturers data *is* pretty close to push processing.

For example, the last time I used Agfa APX 400 it was nowhere near a true 400 film. I don't know how Agfa arrived at that rating but I have to assume they adhered to ISO standards. It was, at best, a 200 film, and pretty good at that speed. But pushing it to 800, even in a speed enhancing developer, looked like a 1600 push of Tri-X or TMY.

BTW, I'm a push processing fool. You name it, I'll push it. But it's a specific tool for a specific use or aesthetic. It doesn't make for the kind of fine results most folks hope to achieve.

Whew... 'scuse the digression.

Rate the film of your choice at 1/2 to 2/3 of the ISO. Expose carefully. You don't need to bother with Zone System arcana, just use a deliberate approach. When in doubt, use an incident meter - it takes the guesswork out of using a typical averaging reflective meter or even a spot meter when it's not clear which area to meter.

Depending on your enlarger type, adjust the development to suit the needed results. For a true condenser head, give it slightly less; for a diffuser, slightly more. Many countertop "condenser" enlargers of the past few decades are actually hybrids, using a diffuse light source above the condensers - typically an opal lamp or sheet of opal glass/plastic. I tend to develop for that type of enlarger as I would for a dichro head.

Do this and just about every negative on a 35mm or medium format strip will print without much fuss.

Example: the best results I've gotten with FP4+ were attained rating it at EI 64 and developing in ID-11, 1+1 dilution, for 9 minutes. The scenario was very tricky, bright sunlight dappled through heavy tree cover. Contrast was perfect, no need to fiddle with dodging and burning or selective use of magenta/yellow filters. Grain was remarkably fine - even a 16x20 from 35mm would stand up to most scrutiny. It wouldn't rival medium format, but came awfully close.

For even finer grain you might try Perceptol, or just use ID-11 or D76 at full strength. This might reduce acutance a bit but grain will be finer. Actual detail won't be reduced, just the impression of fine detail due to the difference in edge effects. Depends on the subject matter. For landscapes and subjects demanding critical detail, lean toward more acutance; for portraits, or subjects will large expanses of same/similar tones (large bodies of water, skies, etc.), acutance is practically irrelevant, so develop for the finest grain.

And be careful with that diet. By January you'll be a mutant hybrid noodle-person. At least toss some cilantro, chives or red pepper in there. Or find a good cheap place for pho. Ask 'em for tips on making noodle soup enjoyable to live on.

Sounds like you got some good responses. I say go with Tri-X. Actually, I say buy a roll of Plus-X and a roll of Tri-X, shoot them both on a test subject and make some prints. You don't have to make 16x20 prints - just set the enlarger as if you were going to make a print that size and then use a sheet of 8x10 or 4x6 just to test to see if the grain is objectionable.

I like Plus-X. It's a good film. I think it mixes well with Tri-X and have no problem using it when I want a slower film. Then again, a couple of my cameras only have a max shutter speed of 1/1000, so Plus-X lets me back off a little bit when its bright out.

IMO, Plus-X is not an old or poor choice for any outdoor photography. It is a very different film from Acros, but not worse. Acros is a t-grain/new technology film and is very fine grained. Plus-X is a convention grain film. It's more a question of what look you like, not a better or worse contest. Try some of both.

Tri x at EI 200 with reduced development, yields beautiful negs. D 76 stock 4.5 min at 68. or D76 1:1 6.6 min at 68. When you show the prints, they will not believe it is tri x usless you show the neg.

Plus x is better at 125. D 76 1:1 7.5 min at 68. I don`t have a time for D76 stock, but .65 x 7.5 will be really close.
If you can work at EI 64, plus x times are 3.4 for stock and 5.6 min for 1:1 at 68.

These times are for well calibrated meters, shutters, thermometers, condenser enlarger and for D76 that is stored in full bottles less than 6 months. One week with air in the bottle and the times are off, first too long, then it dies fast and times are too short. I mix a liter and decant into 4 oz bottles immediately upon cooling. I either use it up or throw it away after 6 months wichever comes first.

Like Lex explained, these will be negs you will not believe for quality. I only wish I know this much when I could get Panatomix x now long discontinued. Tri x and Plus x are different films now so maybe it would have not bee nso good.

Regardless, the key is sufficient exposure and minimal development for best quality. Brand and speed of film do not matter.

Test your equipment first and print a section of 16z20 to see how it is working.

To work at the short times, drop a tempered reel and film into the tank already full of developer, cap and agitate. Start pour out at 15 sec before the end of time. Use NO water or stop bath and go straight to fix. Either has the effect of diluting the developer and increasing grain. The penalty is shortened fix life. So what! Agitate 30 sec on immersion, and 5 cycles up and down every 30. Don`t get into some crazy scheme of gentle agitation.
The tri x will scan fine. the Plus x will print perfectly on #2 paper just like tri x, but the highlights will block somewhat if you scan. Recucing the time somewhat will improve scanability, but not fix it. This is all for darkroom prints on condenser enlargers. Add 10% for cold light of diffusion.
The best film I have used for both print and scanning is Delta 100. All the same rules apply.

If you are enlarging to 16x20 or larger and shooting 35mm expect the grain to be prominent. I also disagree plus-x is poor choice. Shot at 100 and developed in D76 it's one of my favorites and certainly finer grained than Tri-x.

Plus-X is an excellent film.
I shoot it @ EI 64 and develop in Perceptol 1+2, 68F, 10min, agitation every 1 min. I had absolutely no problems with printing the negatives (grade 2).
The film is very sharp. Grain will not be a problem.