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With very many errors. The Massive Development data is deficient in two regards: first it accepts user experiences which, in my opinion are ill founded, full of poor practices and second: many charts are simple numeric extrapolations, and we should know that is a wrong way.Quote:
Originally Posted by Pere Casals
Ooops I thought you meant the Zone System as covered in The Negative. Noted! Took a peak at the preview and TOC on Amazon and yes this looks quite fantastic for the subject at hand (latest revision was updated in 2013 as well!?). Added to my list of must-have books, thanks!Quote:
Originally Posted by Pere Casals
Ok... don't consider the Development Chart, let me correct my statement: just see recommended developments in the TMX datasheet for diverse speeds:Quote:
Originally Posted by Jac@stafford.net
> 100 speed is ISO, it is for sure that the toe is at -3.3 stops with recommended standard processing, and it delivers standard contrast.
> 200, 400, 800 EI are film Exposure Index, non ISO, and not speeds. With the recommended development by kodak the toe may not be at -3.3 so it isn't with a new speed, but a way to make a printable negative. For this reason the say EI and not Speed:
Attachment 186477
> Somebody saying he rates TMX ISO 80, this is not a film speed if he made no calibration, this is how he shots... , this is also for sure.
> Using a high speed developer would modify the film speed, this is: it modifies the required exposure for a spot to be in the linear region and outside the toe.
If you follow Adams' recommendations in his book The Negative, and don't take all his disclaimers into consideration, you will make nothing worth printing. Ever see that photo of him dressed as Moses with the Ten Commandments done by his followers? The highlights are all blown out and the shadows are opaque because the negative was so thin they had to print on #4. At least Davis reveals in his complicated system that the effective speed of TRI-X developed in HC110 B for 5:00 at 68* is 64. Picker claimed some complete understanding of Adams' system and offered to give you your personal EI for $5 if you send him your test negative to measure. Adams hated Mortensen , probably because of all the beautiful women that posed for Mortensen, but his book "Mortensen on the Negative" shows you how to read a negative without a densitometer and make the appropriate adjustments.Quote:
Originally Posted by Pere Casals
Yes... one thing is a recipe to get a working method and another one is BTZS. There are many good recipes out there, everyone is good if we make some personal adjusments for it.Quote:
Originally Posted by Neal Chaves
But basicly BTZS is not a recipe, it's a compendium about technical sensitometry. It (primarily) not tells you how to expose/process, it tells what we'll obtain depending on how we expose, process and print.
With a calibration and a spot meter we can predict what particular density we'll obtain in the negative for an scene spot, and the same for the printing process. So it opens the scope of photographer's mentality.
BTZS is advanced knowledge that may not be necessary most of the times, but if we want to adjust (for example) a reversal processing it will save a lot of repetitive testing.
You know, all the information above is correct. It just seems to me that we often dump more information and techno-babble on to someone looking for a basic, halfway-easy-to-comprehend answer that we risk overwhelming them with detail.
Let me attempt a simpler, albeit less-detailed, reply directed at the OP's questions:
First, as mentioned above, standard ISA film speed is determined by lab testing with specific parameters for exposure, developer and amount of development.
In practice, any of these parameters can be different for us.
1. If we use a different developer, it might not give the same film speed as the lab standard. This happens all the time. Differences are in the range of one-stop slower to a bit faster (the extremes being attainable only with more specialized developers). For example, HC-110, according to Kodak, will give an E.I. about a third of a stop slower than ISO standard.
2. We more than likely all meter differently than the lab standard, whatever type of metering we use. This affects where the low values get placed on the film. We may have to add more exposure for our way of metering to get the shadow detail we like.
3. We often don't like to develop as much as the ISO standard, usually to keep highlights from becoming difficult to print, etc. Changing development time has a small effect on film speed; less development = slower E.I. and vice-versa. We may need to adjust our E.I. to match our desired development time.
4. Finally, some smaller manufacturers don't rate their films so precisely to ISO standards, so they may be overstating their film speeds a bit. We need to test and adjust for that.
Yes, you should judge your film initially at published box speed and using the developer and developing time recommended by the manufacturer. But then, be aware that some of the above discrepancies will likely come into play and you'll have to make adjustments. If you don't feel like learning the Zone System or whatever right away, just follow Kodak's age-old advice: "If your negatives consistently have too little shadow detail, increase your exposure (i.e., slower E.I.). If your negatives are consistently too thin (i.e., underdeveloped so you don't get light enough highlights), then increase development time (and vice-versa)."
Keep in mind that exposure determines how much shadow detail is recorded on the film. This is a function of the built-in speed of the film and can't be changed very much by development; just by a little as mentioned above, and that usually on the slow side.
Development controls the contrast spread from the more-or-less fixed shadow details to the highlights. We can increase the contrast (difference in density on the negative) between low and high by increasing development and vice-versa. We fine tune our development time to find the best compromise for us. Zone System users have different development times for scenes with different contrasts, but many just find a good middle time and use the contrast controls available when printing to make up the difference (especially roll-film users who can't easily switch development times for different frames). The idea is to be in the middle of your adjustments for a "normal" situation so you have room on either side to deal with more or less contrasty scenes.
One comment about "pushing": As mentioned above, this is basically intentionally underexposing the film (i.e., losing shadow detail and placing the highlights somewhere on the usual mid-range of the negative) and over-developing (to get those muddy highlights up to where they should be!). This results in a printable negative with a lot of separation between tones and no detail in the darkest shadows. This is fine for many low-light situations where making the shot would have otherwise been impossible; it is even a "look" that people have learned to like and so gets used for "normal" situations as well. If you want full shadow detail, however, you need to make sure you have enough exposure. How much shadow detail is enough for you determines your E.I. for any particular situation.
Hope this helps,
Doremus
Required shadow detail also determines the effective film speed because the low value densities (Zone I-III) are set largely by exposure with development having very little effect on them. As noted, if you don't get the information on the film, no amount of development is going to bring it out. Use the film speed that will give a Zone I density approximately 0.1 density unit over the film base plus fog (fb+f). Develop the film to give a Zone VII exposure a density reading of approximately 1.15 over the fb+f. This requires a densitometer, however and I think I've offered to ready anyone's negatives who sends them to me for the cost of a SASE (as long as it doesn't get out of hand which I doubt it will). Cheaper than Fred's $5 cost as Neal noted. For the same $5 you can buy a used copy of Picker's the Zone VI workshop, which is more readable and easier to understand than Adams' the Negative. Just PM me for the address if you want me to read your negatives.Quote:
Originally Posted by Doremus Scudder
I'll stay on the sidelines chuckling this time.
Thanks for the discussion folks! I ordered Beyond the Zone System as it seems like a great read but also learned quite a bit just right here. In regards to the offers to do density testing of films, it sounds like to do that I would need to shoot a gray card or a test card in expected lighting setups to get good data from that? I'm not sure I'm quite ready for that but I do think it's a worthy exercise.
For now I am still seeing that Pancro 400 seems to work better more at 200 given my meter, lens, and subject combinations so far. I get better shadow detail. Admittedly I'm not properly using the zone system in these cases and it's been in shade or artificial lighting. I suspect a bright sunny day with a very wide dynamic range will be different (from what I've read, Pancro 400 provides a bit more shadow detail than HP5 in this regard). I definitely like it, not sure if I like it more than HP5 yet though. I still need to do some portraits with it and more shooting in general, but will probably shoot it closer to 200 until I work my way through BTZS, The Negative, and am able to consider doing some testing.
I do agree with some of the sentiments that one can over-complicate this to the point all I'm doing is taking lab shots. I don't want to go that far, and I do have a tendency towards over complication :) But I think getting a better handle on negative exposure and evaluating things would be helpful. I'm not applying it particularly well but I do think I favor the zone system, at least when doing serious shooting in 4x5. For 35mm, I think just adopting a pull/push mentality tends to work better for me since the photos are more snapshots and tend to be taken with haste. HP5 at 800 tends to work well for me - I like the look and I get good negatives so I'm not too bothered by it. 4x5 is certainly another story - part of the reason I shoot it is because it's methodical and it stands to reason being more calculating about exposure makes a ton of sense to me.
You don't shoot a gray card, but work with either a transmission step tablet or reflection gray scale, containing a full range of gray values from black to white. This is then measured with a densitometer and plotted. All a gray card does is indicate "middle gray" (Zone V), which might or might not indicate the middle of the true film scale. Simple gray card readings work better in color photography.