Designing T-Max Films: TMX speed; In response to David Williams' request

[David R Williams]

Ok, so confession time...my acutance issues may be due to an oversight on my part due to my much (un)loved Omega C760's negative stage and my ageing eyes.

When all fails, check everything....and maybe some other stuff too...

My C760 is bolted to the wall using a wall support base on the bottom of the column and top mount for the column head which together rigidly attaches the column to the wall.

However, that wall is subject to load from above and unfortunately part of that load is a torture test: our washer and dryer are on the floor above the basement darkroom and that wall is hung from the joists of the floor above.

So, the wall is subject to periodic vibration which shouldn't be a problem as long as I'm not printing while laundry is in-process, but it seems that the highly "adjustable" negative stage in the C760 shifts it's negative stage alignment as the result of it's less than optimal engineering.

Specifically, the negative stage is designed with a sprung base under the negative carrier and relies upon the lamphouse positioning to hold the negative holder in alignment using 4 adjustment screws at the back of the lamphouse. These screws are quite difficult to use to align the lamphouse and negative carrier (even with a laser alignment tool) and quite apparently, and I've now determined will shifting due to vibration.

After checking and re-aligning the enlarger last night and reprinting a 120 TMX neg developed in Perceptol 1:3, the 16x20 test size enlargement is crisp, sharp, smooth and detailed everywhere, especially in off-centre parts of the image that are best to evaluate acutance.

Lesson learned - I'll confirm alignment before any meaningful printing session.

 

[MTGseattle]

I just tried to google the date of transition from old tmax to TMY-II and I do not trust the results I am seeing. I have a chance to get some 2008 confirmed frozen Tmax 400 in 4x5 for a really attractive price compared to current retail.

 

[Milpool]

TMY-2 was released Oct 2007

I just tried to google the date of transition from old tmax to TMY-II and I do not trust the results I am seeing. I have a chance to get some 2008 confirmed frozen Tmax 400 in 4x5 for a really attractive price compared to current retail.

 

[David R Williams]

I just tried to google the date of transition from old tmax to TMY-II and I do not trust the results I am seeing. I have a chance to get some 2008 confirmed frozen Tmax 400 in 4x5 for a really attractive price compared to current retail.

Do you have an image of the packaging available?

 

[Milpool]

Here is the tech doc which also shows the packaging revision related to the reformulation.

https://125px.com/docs/film/kodak/f4043-TMAX_400-2007.pdf

I just tried to google the date of transition from old tmax to TMY-II and I do not trust the results I am seeing. I have a chance to get some 2008 confirmed frozen Tmax 400 in 4x5 for a really attractive price compared to current retail.

 

[David R Williams]

Here is the tech doc which also shows the packaging revision related to the reformulation.

https://125px.com/docs/film/kodak/f4043-TMAX_400-2007.pdf

That's exactly what I was thinking - great reference document that I couldn't put my hand on.

 

[Milpool]

125px is a pretty good archive.

That's exactly what I was thinking - great reference document that I couldn't put my hand on.

 

[chuckroast]

DK50 was called the poor man's HC-110, and in fact preceded HC-110 in certain graphics applications. I doubt you'll get the same effect without added salt. But might as well try just as long as they're not valuable shots.

Pan-F has such a miserably exaggerated S-curve, with such a brief straight line, that I only got a modicum of cooperation from it using a modified version of PMK pyro. It's really suited more for lower contrast scenes having a dynamic range equivalent to what's best for color transparencies too. But I have gotten lovely Pan F shots in misty conditions, and coastal fog, and mountain falling snow. TMax is just so so so much more versatile.... Speaking of fog, it's starting to lift, along with its chill, so I need to think about heading outdoors soon.

I have found DK-50 to give very low fog but tending toward more grain for a given film than, say, HC-110 or D-76. For MF and larger, it was never much of an issue, though.

 

[Augustus Caesar]

I have found DK-50 to give very low fog but tending toward more grain for a given film than, say, HC-110 or D-76. For MF and larger, it was never much of an issue, though.

Slow films have inherently lower latitude.

 

[John Wiegerink]

I have found DK-50 to give very low fog but tending toward more grain for a given film than, say, HC-110 or D-76. For MF and larger, it was never much of an issue, though.

I remember using DK-50 with some old Ultrafine Extreme 100 film in 120 and it worked very nicely. I figure that with 120 Tmax and its fine grain DK-50 might just be the cat meow.

 

[djdister]

I remember using DK-50 with some old Ultrafine Extreme 100 film in 120 and it worked very nicely. I figure that with 120 Tmax and its fine grain DK-50 might just be the cat meow.

I recall using DK-50 for 4x5 and 5x7 Ektapan and Tri-X many years back - it was an easy developer to work with and clean working.

 

[mshchem]

Grain helps with the mostly subjective phenomena of apparent sharpness because it contributes some edges.
Acutance - observable edge contrast - is a major component of what we perceive as sharpness.
Resolution contributes to perceived sharpness, but they are not the same.

This is too technical for my feeble mind.

I just go back to 1940's Kodak "brilliant negatives" "fine grain" "snappy" or good old Ilford Hypersensitive Panchromatic. That's proper film speak.

 

[MattKing]

This is too technical for my feeble mind.

I just go back to 1940's Kodak "brilliant negatives" "fine grain" "snappy" or good old Ilford Hypersensitive Panchromatic. That's proper film speak.

Think of it this way: a little grain gives some "bite" to the image!

 

[Doremus Scudder]

It wouldn't be the worst option in the world to use TMY for everything either.

Especially if you find you need the faster shutter speeds available from 400 vs 100 ISO films.

Doremus

 

[GregY]

Especially if you find you need the faster shutter speeds available from 400 vs 100 ISO films.

Doremus

or to compensate for using filters.....

 

[mshchem]

Think of it this way: a little grain gives some "bite" to the image!

Perfect! Now you're talking!

 

[Lachlan Young]

Lesson learned - I'll confirm alignment before any meaningful printing session.

What you've found is the reality that a very big percentage of the claims from home darkroom users about acutance often boil down to people failing to identify intermittent vibration or alignment problems in enlargers, or using consumer grade scanners that are fundamentally unsharp.

regarding the chromogenic B&W films but my two cents is they are way underrated

I'd agree that XP2 Super (having printed and scanned a lot of images from it in adequately tightly controlled conditions, and in comparison to many conventional BW films and developers) is very sharp and fine grained in the highlights (just with more apparent granularity in the shadows as usual for chromogenics) - I think the main reason people don't like it is that it very firmly demonstrates the abilities of real photographic engineering to deliver an actual compensated highlight curve without mucking up the toe or midrange (assuming the end user has the baseline ability to expose it sensibly enough to get a print with decent highlights on less than G5) and they deliver their most optimal results in utterly normal C-41, not something cooked up in a garden shed by people in active denial of post-1945 photographic science. What's more amusing still is that there's an article to be found in the depths of some US photo magazine or other from the early 1980s where one of the creators of cookbook-repeated POTA derivatives for Tech Pan states that he's given up on technical films and specialist developers in favour of XP1...

Perceptol 1+3 is unlikely to promote a meaningful increase in edge effects. Presumably the idea behind this is (loosely) based on dilute metol-only / low sulfite developers enhancing edge effects, but it's not quite as simple as diluting Perceptol 1+3. It would really need to be further diluted, not to mention alkalinity is an important factor (and based on the research I've seen, the pH of Perceptol is less than ideal for enhancing edge effects with metol although to be fair that research pre-dated tabular and/or core/shell iodide etc.). The attributes of a developer that generally promote edge effects also tend to increase granularity.

The big discovery seems to have been that specific PQ ratios could do what very dilute (0.5g/l) metol only developers could do, but with the ability to be used across a much wider array of circumstances (and especially in replenished systems), with an easier choice of pH optimisations for fine grain or sharpness. And emulsions changed to maximise developer interactions for beneficial inhibition effects in the manner of the DIR couplers in chromogenic/C-41.

Slow films have inherently lower latitude.

Not really, at least not those made with reasonably modern technology. They do tend to develop faster (and may go to higher max densities), so it's more accurate to describe some as being rather less resistant to gross user error (and some have engineered-in components to regulate the development time for this reason).

 

[flavio81]

I thought chromogenic XP2 was the least versatile,

Can be developed in C41
Can be developed in B/W chemistry
Can be used at iso 50, 100, 200, 400, and even beyond that.

How can it be the "least versatile"?!

I also wonder how long those dyes will hold up.

If you develop it in B/W chemistry then the image will not be formed from dyes.

Lachlan could comment in more detail regarding the chromogenic B&W films but my two cents is they are way underrated (for lack of a better word).

I found XP2 pretty good but I only used it with C41 process. Now i've seen online the results one can get in regular B/W chemistry and... WOW! such fine grain and image quality!

Ilford is underpromoting XP2.

 

[Lachlan Young]

I found XP2 pretty good but I only used it with C41 process. Now i've seen online the results one can get in regular B/W chemistry and... WOW! such fine grain and image quality!

I've seen the results in the flesh, and people are misleading you about what XP2 looks like in regular B&W chemistry vs C-41, possibly because their means of digitisation is so poor in terms of accurately reproducing XP2's qualities in the first place. There is no comparison. C-41 enables the DIR couplers to work, which is a very large part of how fine, sharp grain and the large density-handling latitude are created. Without them, it's not got any advantages whatsoever over a competently developed regular B&W film. Ilford are correct in stating that you can develop XP2 in B&W chemistry if essential, but it will have none of the qualities that make XP2, XP2.

 

[pentaxuser]

It doesn't! We're not talking about "full strength" Perceptol here, but diluted 1+3 or even 1+4. It's not so much the Sodium Chloride doing the grain softening in Perceptol, but the high Sodium Sulfite content that softens the grain more. When you dilute the stock developer it also dilutes the high Sodium Sulfite content, which in turn enhances the sharpness/edge effects.

So if Sodium Chloride does nothing then presumably D23 which is Perceptol minus the salt will produce the same effect at 1+3 or 4?

pentaxuser

 

[chuckroast]

So if Sodium Chloride does nothing then presumably D23 which is Perceptol minus the salt will produce the same effect at 1+3 or 4?

pentaxuser

I've never tried it with salt, but I routinely use D-23 1+9 and add 0.5g/l of NaOh (lye) and semistand develop film from 25-40 min in it.***

This combination will give you razor sharp negatives. (It's also really inexpensive. A back of the envelope calculation the other day suggested something like $0.10 to $0.15 per roll.)

Here are a couple of scans of silver prints from recent 35mm FP4+ negatives processed that way:

(FP4+ @ EI 125, Nikon F2, 50mm f/1.4 AIS Nikkor, handheld)


***Lye should be handled with care because it can burn skin, destroy eyesight, and generally is nasty to human tissue. It is also exothermic and will get very hot if liquid is added to it, rather than the other way around. Hence eye, skin, and clothing protection is mandated as are ventilation and masking to prevent inhalation of the dust, not to mention good lab safety practices.

 

[Milpool]

So if Sodium Chloride does nothing then presumably D23 which is Perceptol minus the salt will produce the same effect at 1+3 or 4?

pentaxuser

Basically yes, although D-23 would likely be slightly coarser grained than Perceptol and perhaps give very slightly higher emulsion speed.

 

[MTGseattle]

Do you have an image of the packaging available?

That's a good point. The film may have sold, or the sellers ad expired. I couldn't find the listing again. Thank you for that link.

 

[MTGseattle]

TMY-2 was released Oct 2007

Thank you

 

[DREW WILEY]

Perceptol without salt isn't Perceptol - it's integral to the formula itself. And dilute D-23 doesn't give the same effect as dilute Perceptol, so there's that. Some of the comments on this thread seem like armchair quarterbacking - opinions without the experience to back it up (and I don't mean smudgy web scans as alleged "evidence" for this or that).