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How to get grain-free black and white negatives?

No the parts you obviously haven't read where is says for T-MAX 100

This film features medium speed (ISO 100/21 in most developers)
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and for T-Max 400

It has high speed(ISO 400/27 in most developers), very high sharpness, extremely fine grain, and high resolving power
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I take it that's what you mean by:
there is absolutely no mention in the tech pub for Tmax that these films are “ISO xxx films
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So go back and actually read the publication so that you have a clue what you're talking about instead of mis-leading people with incorrect garbage. It's no wonder people get confused. You seem to be one of them yourself.
 
WTF?? RTFM???
 
The interesting bit is I have the ASA and DIN developer formulae somewhere, Adox Borax MQ which is very close to the ASA formula and an Agfa & Agfa Ansco formula all used to give box ASA (now ISO) with almost all films. It's similar to D76/ID-11 but with less Sulphite, in fact it's closer the optimum level for a fine grain developer and causes less speed loss and gives fine grain and better sharpness.

Tmax films did not work as well in D76 or the ASA developer, hence the ISO standard was changed to allow a different developer, Kodak had to work hard to introduce developers that worked better with the films, first with Tmax developer which gave better shadow detail and then Xtol which without doubt is the best film developer Kodak has made.

I'm fed up with being told my tests for personal EI are wrong, particularly when they mirror exactly what Kodak themselves recommended & published, it's time those that disagree come up with some factual truths and examples.

Ian
 
RobC said:
...So go back and actually read the publication so that you have a clue what you're talking about instead of misleading people with incorrect garbage. It's no wonder people get confused. You seem to be one of them yourself.
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That's the thing, “ISO 100/21 in most developers” is far from reality as far as TMax is concerned.
 

Personal EI should be taking out minor discrepanices with meter accuracy and personal processing technique so nobody can say a personal EI is wrong. They are just different and include a myriad of things which are different from a manufacturers lab test.
But its not necessarily safe to assume that they are different because of the way the standard has changed.
 

Actually the third document tries to answer “...why some Kodak films have ISO ratings while others have EI (Exposure Index ratings), or some may have neither...”.

And the actual, current ISO standard for speed was changed mostly because Kodak needed it.

and when people ask why Tmax 400 is more like ISO 200, Kodak fanboys look sideways.. lol

Epic!
 
Michael R 1974 said:
....
Again, who's asking "why TMax 400 is more like ISO 200"? That statement doesn't make sense. The people asking that clearly don't know what ISO 200 really means.

Epic indeed!
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Kodak are swapping EI 100 and ISO 100 for their films, so we can start using them this way, No?
Let me help you, according to my experience Kodak Tmax 100 is EI 50, Tmax 400 is EI 200; in D76.
 
georg16nik said:
That's the thing, “ISO 100/21 in most developers” is far from reality as far as TMax is concerned.
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I agree. There's absolutely no way Tmax 100 would be 21 DIN if subjected to the DIN testing methods, it's only allowed to use the rating because the ISO system allows an ASA speed to translate to 21 DI\n even after Kodak fiddled the ASA tests for Tmax films.

Some of us were around at the time, I have the articles from US publications which made it clear that Kodak's ISO speeds for Tmax films were inlated.

That doesn't make them bad films Tmax 100 was the 2nd placed film for many years but lost out as it was a full spo slower than APX100, that's from personal experience and later magazine tests, the late Peter Goldfield a UK photographer and educator who assisted Minor White found the same.

It's time that those that do (use and shoot film) made sure that those spouting off their unfounded statements and theories back them up woth hard facts or examples.

I find it very interesting that the theorists who are ALWAYS right don't post images. There's no room for deceit.

Ian
 
Michael R 1974 said:
Regarding Kodak tinkering with the procedures (ostensibly because the TMax films did not work well with the specified developer), the speed/contrast criteria did not change. That point keeps being missed.
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No the point that's constantly being missed is that by changing to a different developer you can influence the speed and contrast to meet a specific criteria.

An example would be Ilford's 3 powder developers Perceptol, ID-11 and Microphen all give different speeds with the same film processed to the same contrast. In Kodak's case it's now D76 in the absence of Microdol-X and then Tmax developer and Xtol that give slightly beter film speed and shadow detail.

The point being if Ilford were to use Microphen instead of ID-11 to test their ISO speeds then they could claim higher figures in the case of FP4 it woould be 200 rather than 125 ISO.

I think the down rating films by a stop (to half box speed) that Xmas (Noel) refers to and uses comes from Ansel Adams "The Negative" where he recommends careful exposure of the shadows and N-1 development (reduced development) with 35mm and Roll films, his reasoning is that way you can cope with most types of light including when it's quite contrasty. That's not an approach I've ever used and is not the same as the Zone System, BTZS or even the old addage exposuse for the shadows, develop for the highlights.

Ian
 
Hi Ian

Yes overexposure is not like under exposure. It is well difficult to print clear film, spent weekends trying to.

But if the OP does not like grain then XP2+ does not have conventional grain unless you underexposed it say 1600 ISO when it shows 'digital' noise in shadows. At 50 ISO there is no grain and all you need is a c41 lab where they look after your film, or c41 kit.

Noel
 

You mean white noise [I know it is not white but the noise is called white noise] not digital noise. Digital is not always the problem for everything, even though it seems like it sometimes.
 
Sirius Glass said:
You mean white noise [I know it is not white but the noise is called white noise] not digital noise. Digital is not always the problem for everything, even though it seems like it sometimes.
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Yes maybe.
Digital grain occurs predominately in shadows.
XP2's noise at 1600 EI is similarly biased.

Silver grain appears more noticeable in mid tones.

So maybe that is what I was trying to say...

I was trying to stay away from theory.

XP2 won't show grain normally.
 

Yes, tabular grain films so much less grain than traditional grain. Less grain but not grain-free.

By the way if you avoid grain completely you are endanger of become gluten free.
 

I have a slightly different view.

Most (or all!) continuous-tone B/W films work perfectly fine in D76 and I dare to say that it's a generally accepted practice that "real speed of the film" = "required speed for developing in D76 in such a way shadow detail is fine".

There are speed-increasing developers as well, which enhance speed in any film. For example Microphen. Example: HP5+ gives "real speed" 400 using D76; with Microphen, even faster.

If Tmax 100 does not appear to give full "100" speed in D76, is not because it "does not work well in D76", but because is slower than 100 "real speed". And thus a speed-increasing developer is preferred. Xtol being the ultimate developer ever made. But TMX does work well in D76 since it can give beautiful results, just not when rated at "100".

In the same way, Fomapan 400 does not give real 400 speed in D76 not because it does not work well in D76, but because it's "real speed" is about 200-250.

In short, i do suspect Tmax is not real "100" speed, from my limited experience with it, as well.
 
Michael R 1974 said:
In your experience, how specifically did you find your EIs?
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My EI is pretty content, thanks for asking.

flavio81 said:
...In short, i do suspect Tmax is not real "100" speed, from my limited experience with it, as well.
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Flavio, to some extend Kodak Tmax 100 reminds me of Kodak P3200 TMZ, the Ilford Delta 3200, the Foma you mentioned, etc.
These films carry misleading optimistic numbers on their boxes, so that they appeal to customers.
The ISO standard call this “...the tradition of associating a specific speed value with a particular product...”

The price to read the whole ISO poem is 38 Swiss francs.
http://www.iso.org/iso/home/store/catalogue_ics/catalogue_detail_ics.htm?csnumber=3580
 
Sirius Glass said:
Yes, tabular grain films so much less grain than traditional grain. Less grain but not grain-free.

By the way if you avoid grain completely you are endanger of become gluten free.
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XP2 is not a tabular grain film. The image is made up from dye molecules (zero grain).
 


You've got it 100% right there Flavio, and that's what some can't grasp, it's nothing new I remember discussions about ASA/BS speeds in the late 1960's and early 1970's and nothing has changed. The reality back then is we knew what EI and dev times gave the best results under different conditions.

It's far more important to do your own speed and development tests to optimise your work flow, That way you can be confident of repeatable high quality results. From memory it took me less than two hours to test Fomapan 100 & 200 and determine the best EI for normla use and the optimum dev time.

A few quick simple tests will cut your film wastage, make sure you get the best possible results and help you have negatives that are easy to print in any way you want (or scan).

Ian
 
I'm going to throw something out here ......

Speed arguments are intriguing, because they are a little bit like religious arguments. There is rarely agreement, because people want different things.

Ian has stated inumerable times that Kodak took steps to change the ISO standard because TMax didn't score well under the old standard. While that might explain it, I think it is more likely that Kodak and others were generally unhappy with the older standard.

Many of the posters here on APUG do fine quality work making use of techniques that rely on Zone System or similar procedures. Those systems are oriented to people who exercise extensive controls over their materials, including printing controls. They were also developed with older materials.

Kodak, and other mass market manufacturers required a system that was suited to commercial processors and high volume applications. They needed something that was matched to more modern materials, and delivered a greater percentage of pleasing prints to a large number of users.

The more modern ISO standard appears to have been developed with tools that factored in perception of prints. I would hazard a guess that those prints were relatively un-manipulated prints.

A speed rating that yields slightly less shadow detail but better rendering of highlights may very well yield a higher percentage of pleasing un-manipulated prints.

It may very well be true that the "new" ISO film speed standard is not as well suited to Ian and George's needs as it may be to others. While at the same time being better suited to a whole bunch of other users - particularly those who use labs.

And the same may apply to the more modern films.

It certainly seems likely that a standard based on fractional gradient would yield very different results than one based on base fog + 0.1.

Because they measure different things.
 
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ISO 6:1993 is the standard for determining the speed of negative black and white material. It deals with "how to" as does most standards. You will need to read the scientific papers behind the standard to understand the theory. Start with Loyd Jones' seminal papers and the concepts of limiting gradient, fractional gradient method, and print speeds. Two papers that relate to the 1960 standard are Simple Methods for Approximating the Fractional Gradient Speeds and Safety Factors in Camera Exposure. These two papers will explain the reduction of the safety factor, exposure constants, and the Delta-X Criterion of speed determination which the current standard uses. They can be found at http://64.165.113.140/content/benskin/.
 
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Ian Grant said:
I'm fed up with being told my tests for personal EI are wrong, particularly when they mirror exactly what Kodak themselves recommended & published, it's time those that disagree come up with some factual truths and examples.
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A person's EI is just that. It's an approach they determined to work for themselves. The concept of film speed and the standards and the what the manufacturers say is different.

I've shown you the source for the Sexton quote. He wrote, "As with most black and white negative films I used an Exposure Index (El) that is less than the manufacturers' suggested film speed." This is because he does Zone System testing which I have repeatedly shown has a different methodology. There's nothing wrong with Sexton's EI, but it's not film speed. And that's the point. Being right or wrong about film speed doesn't have anything to do with a personal EI. People need to understand there is a difference between film speed and their own personal working methods and shouldn't conflate them intentionally or not.

As for the Kodak source, I'd love to see the factual example you keep sighting.
 
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This is awesome!
 
> Digital grain occurs predominately in shadows...
> Silver grain appears more noticeable in mid tones.

It is most present in the highlights but less visible there: The difference between white and nearly white is small. But when you bring the highlights to mid densities the grain is very prominenet. Mostly this happens by burning the sky.
 

Essentially you're saying the same as I am, that personal EI is a different approach to using the film's box ISO. I've never seen the article were John Sexton said that, but the use of the word most is interesting. I don't really agree with his statement as it doesn't mirror my experience.

I'll try and find the original Kodak Tmax Datasheet, it's not where it should be but I've not got totally straight since moving house last year. I have an early datasheet and in the Exposure section Kodak refer to the Nominal speeds of Tmax 100 & 400, at the bottom there's notes on adjusting exposure if negatives are too light, or dark, flat or contrasty. I have a feeling the other Kodak A4 Tmax publication was more of a sales brochure than a datasheet as it was illustrated and that's definitely the one that suggests using Tmax100 at 50EI for better shadow detail and tonality (longer tonal range). I'll scan it when I find it.

There's a possibility that some of Kodak's UK publications differ from the US ones, I notice the Tmax datasheet in front of me which I'd guess is from 1986 was published by Kodak's Professional Photography Division in Hemel Hempstead in the UK. I say 86 because there's a reference to T-Max developer being available mid 1987.

Ian
 

Try again then - in 1961 'they' changed the speed of HP3 from 200 ASA to 400 ASA, the technical article justifying the change would not have passed my peer review.

The box in the local shop still said 200 ASA.

The change did not account for normal photo practices, or how silver halide works.

The 'zone' people did not change either so I'm in good company.

So which para did you not understand?
 

Speed methodology has changed multiple times over the last 100+ years (since Hurter and Driffield's Inertia Speed). What made the fractional gradient superior is that it was rooted in psychophysics. In Berg's Exposure: Theory and Practice, he writes, "With this criterion, we complete the circle which started from a purely academic linking of the speed with an almost entirely arbitrary property of the characteristic curve, then led us to the purely practical concept of speed, to end up with what appears to be the most successful attempt so far of connecting print quality with a characteristic of the negative material."

The Zone System methodology didn't change because Adams probably didn't understand. The correlation between the ZS EIs and the fractional gradient speeds wasn't a coincidence. Adams corresponded with Mees and credits him in The Negative. Let's not forget Adams thought the K factor was some sort of conspiracy so the company you find yourself in is questionable.

Saying the 1960 standard didn't account for normal photo practices is simply an opinion based on personal taste. If you don't like the change, fine. It's up to you how you like to expose. The fact is, the reason why it was changed was to update it to reflect the current general use with the newer technology and the greater use of 35mm format.
 
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