TMY film and Xtol developer

[Bruce Watson]

Other suggestions?

Ah yes. XTOL did have a problem years ago that was traced in the end to excessive iron in the mix water. Search for "sudden XTOL failure" and you'll probably find those old threads. The cure for this is to buy a gallon or two of steam distilled water at your local supermarket and mix with that.

I've had XTOL stock last over a year when mixed with distilled water, and stored in old wine bottles using a Vacu Vin stopper. An excellent way to store stock developer; I've never had it fail.

[HartleyFalbaum]

Thanks for all the prompt help! Much appreciated.

[Pere Casals]

This is... odd. Everything I've read since TMAX came out in... what? 1978? shows that the Tmax films don't really shoulder at all, and I have no idea what you mean by clipping.

I remember reading a Kodak tech. bulletin from the 1980s where Kodak was reporting that Tmax (probably Tmax 100) was good for 20 stops linearly. In the lab. Because Kodak had lab equipment that could read through a negative that dense. You couldn't print it in the darkroom, nor scan it on a drum scanner. But Kodak said it was flat and linear out 20 stops.

The point they were making was that the Tmax films don't shoulder off. They have a short toe and no shoulder. The most linear films made. I can only think that TMY-2 is exceedingly linear.

Hello Bruce,

This is way easy to be clarified, just look datasheets and charts that show Lux·Second to Density, Lux·Second is in a logarithmic scale, so one unit more in the scale is x10 more in linear magnitude. See charts, please, the graphs just tell it.

http://www.kodak.com/global/en/profe...4016/f4016.pdf
http://www.kodak.com/global/en/profe...4017/f4017.pdf

I like Kodak products because technical information is concise and exact. Another thing it's what aesthetic application one do with each film properties... of course !

Also see that T-Max has higher blue sensitivity in the spectral graph, this leads to something: by using a filter one can make work a film like the other in what colour to BW conversion concerns, and by placing a pale yellow with T-Max, or a pale blue with TX they will be similar in that sense, the graph explains it.

By clipping I mean saturating to DMax, so the point where highlight details cannot be recovered because the information is not recorded.

Regards

PD: 20 stops is with POTA developer, that one used to photograph nuclear bomb explossions, chart in pdf shows the lux·seconds range for common developers, and it is way, way far from 20 stops.

[Pere Casals]

Thanks for all the prompt help! Much appreciated.

Not at all, it was a pleasure to share it, anyway check all information : )

[Bruce Watson]

By clipping I mean saturating to DMax, so the point where highlight details cannot be recovered because the information is not recorded.

Not recorded? Just because you get to the edge of the graph doesn't mean that the physics stops there. Kodak is showing you what is practical to everyday photography. The curves continue well beyond the edges of the graphs.

I think your interpretation of those graphs and my interpretation of those graphs, are (very) different. My interpretation comes from reading what PhotoEngineer (Ron Mowry, teaching emulsion coating classes at Formulary's workshops in Montana last I heard) over on APUG had to say years ago. He straightened out some of my preconceived notions about what films will and won't do, t-grain films in particular. If you want, head on over to APUG and have a go with him. He's a retired Kodak research chemist. Loves to explain this stuff to anyone who asks.

My other main source (besides the usual of Haist, etc.) is emails I exchanged with Silvia Zadwicki and Dick Dickerson, KODAK research chemists (retired of course) who are generally credited with the creation of XTOL.

[Pere Casals]

Not recorded? Just because you get to the edge of the graph

Hello Bruce, I've also seen that the T-Max 400 curve was truncated at the edge of the graph and I asked my self if it was something beyond, if you look to T-Max 100 graph it is not truncated.

Let me explain why I made extensive tests, I'm focussed in reversal process to obtain slides for projection, for personal joy
and beyond contrast control I wanted to see how maximum static contrast could be obtained with projected images, this is something related to DMax and DMin... (Maximum Density will end in deeper projected shadows).

I reached maximum densities with well known exposures, calibrated with an Ocean Optics spectrometer (http://oceanoptics.com/product/usb4000-vis-nir/) and a Teflon target, perhaps with a 1% probable error, I use that at work.

Well... with TMax 400 there is nothing beyond what Kodak shows in their own datasheet, or very, very little, IMHO, as it can be guessed. Kodak, you know, gives precise and complete technical information.

This is why TMax 400 charts of Lux·second vs Density end 1.5 Stop before than Tri-X, IMHO.

At some 0.8 Lux·second T-Max has all of it's grains having lost electrons enough to be fully signaled for the developer reducer action. So at 0.8 Lux·Second TMax is well saturated, IMHO, when processed with common developers.

I'm talking about normal developers, we later can discuss what happens with POTA applied to TX and T-Max, even this developer is recommended for slow films, it looks.

I'm not saying TX is better than T-Max 400 or the counter: never, never, never: This is not like this...

But (IMHO) by grain formulation TX has an additional 1.5 Stops advantage over T-Max 400 with strong highligts, and both can work better highlights from their initial performance depending of exposure-process modifications from "standard usage".

Both have cubic and tabular grains (TX since 2007 also has tabular ones) but in different shares and total content.

[interneg]

(TX since 2007 also has tabular ones)

On the basis of what evidence are you making this claim?

[Pere Casals]

On the basis of what evidence are you making this claim?

"In 2007, Tri-X was extensively re-engineered, receiving the new designation 400TX in place of TX or TX400, and became finer-grained."

I had read that this finer grain was due, in its new grain formulation, to the grains of the bigger size being of the tabular type. I read that a couple of years ago and I don't remember the source, I remember that it was made clear to me, let me search it, also it is possible that I'm mistaken about this.

What is complete clear in that T-Max has a layer of small cubic grains, let me search for the other, this is something that's not in the datasheet...

[Pere Casals]

On the basis of what evidence are you making this claim?

I don't find the source of the information I had, I've posted a new tread to clarify this information, I'd like to know about it

http://www.largeformatphotography.in...77#post1341577

[interneg]

"In 2007, Tri-X was extensively re-engineered, receiving the new designation 400TX in place of TX or TX400, and became finer-grained."

I had read that this finer grain was due, in its new grain formulation, to the grains of the bigger size being of the tabular type. I read that a couple of years ago and I don't remember the source, I remember that it was made clear to me, let me search it, also it is possible that I'm mistaken about this.

What is complete clear in that T-Max has a layer of small cubic grains, let me search for the other, this is something that's not in the datasheet...

Shanebrook's 'Making Kodak Film' has the image of the TMY emulsion I recall.

Many films today have some degree of mixtures of 'flat' and '3D' grain types - all part of controlled crystal growth technology.

http://www.harmantechnology.com/DotN...0/Default.aspx

Re the TX change, I think you might be confusing it with the TMY to TMY II changeover - the TX change happened a few years before, and it'll almost certainly have some degree of crystal control technology in the emulsion.

Ron Mowrey (Photo Engineer) over at APUG might offer more precise enlightenment.