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View Poll Results: Do you believe in true ISO rating 1/3 stop?
Yes! I believe in 1/3 stop difference, no matter the other variables. 86 34.40%
No! There are way too many imponderables for 1/3 stop to make a difference. 164 65.60%
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Do you really believe in exposing at iso 320?
Old 05-09-2008   #1
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Do you really believe in exposing at iso 320?

Based on the premises that:

If it is true that a film's ISO rating is an estimate, and that a camera's shutter speed is always off by a margin and irregular between clicks (if not electronically controlled), and if we agree that manual development is an unexact science (How do you inverse your tank? Are you 100% accurate and constant over time? Is your development time based from when the film is completely submerged to the tank completely emptied or when you start to empty the tank? Those two philosophies easily eat up or add up to 15 second of development time), and is your thermometer accurate down to 0.5 degrees Celsius or fahrenheit? Is your film very fresh? Has it been exposed to temperature variations? And when you meter a scene, are you sure your meter really understood the scene (because only a multi spot metered scene will give a definite accurate metering)? And is your meter really calibrated for 18% Gray? What if it's 12%?

In the end, what's more important: Being consistent and understanding our gear and personal development rituals or is it more important to rate a film at its "true" ISO rating? And is 1/3 stop visible in th end? What tells you it's the film and not your inversions?
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Old 05-09-2008   #2
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Hi NB23,
i do not really care about 0.5 degrees variations. What is the most important to me is understanding my gear and my way of shooting. By trying different process times, different ratings, different exposure metering, i've finally found the way i want the negatives to be
for example, i finally found that tri-x @ 250 developped in Rodinal is the best for me, i found the number of inversions i need per minute, development time etc...
another example : my metering technique is very special ( and may be considered very bad , but who cares, everybody does what he wants ) , i usually do an exposure metering of the ground of the place i'm in ( weird, isn't it ?! )
So for me, i will answer your question by saying that it's definitely being consistent and understanding my gear and personal development rituals that count for me
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Old 05-09-2008   #3
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If you are talking about Tmax400 (new) or TriX, no. I believe in exposing them at E.I. 250.

TriX at 250:



Tmax400 (new):

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Old 05-09-2008   #4
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Ned, I assume you mean exposing 400-rated film at 320? And then developing at the recommended times for 400. Right?

I have been vaguely aware that some posters here seem to advocate such processing. I'm not sure what the point is. To me that's the same as shooting a frame at 1/3 overexposure, except you're doing it to the entire roll. To me, underexposure, or overexposure is a decision I make for an individual shot. I'm not sure what the point is for an entire roll, unless you're using autoexposure (which most folks here wouldn't be caught dead doing), and you think the particular film is rated incorrectly by the manufacturer.

Unless you're correcting a "faulty" rating, it seems like a game you're playing, the point of which I don't get.
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Old 05-09-2008   #5
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John,

I find them slightly overexposed... But they look good, nonetheless.

Now, how do you develop? Do you compensate? If so, this defeats the whole purpose, don't you think?
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Old 05-09-2008   #6
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Quote:
Originally Posted by crawdiddy View Post
Ned, I assume you mean exposing 400-rated film at 320? And then developing at the recommended times for 400. Right?

I have been vaguely aware that some posters here seem to advocate such processing. I'm not sure what the point is. To me that's the same as shooting a frame at 1/3 overexposure, except you're doing it to the entire roll. To me, underexposure, or overexposure is a decision I make for an individual shot. I'm not sure what the point is for an entire roll, unless you're using autoexposure (which most folks here wouldn't be caught dead doing), and you think the particular film is rated incorrectly by the manufacturer.

Unless you're correcting a "faulty" rating, it seems like a game you're playing, the point of which I don't get.
We're talking the same language...
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Old 05-09-2008   #7
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I think it's possible to acknowledge all the issues your questions raise and still believe in 'true ISO speed'. However, for the kind of shooting that interests me (i.e. 'street'), true ISO is the least of concerns, with exposures in a roll all over the place but more often on the underexposed side. Knowing my propensity for underexposure, I rate my film as ISO 320 in the same way (and for the same reason) I make my watch run 5' fast: I prefer to err on the side of safety. Is it enough? Nothing disastrous has happened so far, and on a couple of occasions I got exposures (and made it to appointments) that otherwise I 'd have missed. And that's all.
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Old 05-09-2008   #8
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I've never felt the need to pull a film at all but pushing ... I do regularly as I actually like the look of a film taken in this direction. Aside from trying to compensate for the wrong choice of film for bright conditions when you want to use a particular aperture and have run out of shutter speeds I see little point in pulling. Not quite OT sorry Ned but can someone give me a valid reason for overexposing a 400 film to say 200 or 100 and then having to compensate in the developing.
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Old 05-09-2008   #9
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Ned,

I usually shoot my Tri-X at 400 but tend try to make my exposure errors in the side of over-exposure, so I could be rating my Tri-X at EI 320 in practice. When I am not shooting at rated speed, I would be pushing it, as high EI 3200.

The only thing I try to do consistently is take lots of photos. I set my exposure by eye, I shoot all mechanical cameras, so exposure can easily be off by a stop or two. I have simplified things to shooting Tri-X most of the time and I soup everything in D76 Stock or 1:1. I do use a digital thermometer which is accurate(supposedly) to .1°C, have a consistent agitation method, and use a timer on my laptop. I do not sweat the details.

I am at a point in life where I want things to be simple and uncomplicated and I have applied this to my photography as well. My photography is not the greatest or even as good as it could be if I spent more time and care. But I am enjoying photography now more than ever. I figure that is all that really matters.
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Old 05-09-2008   #10
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Quote:
Originally Posted by Keith View Post
...can someone give me a valid reason for overexposing a 400 film to say 200 or 100 and then having to compensate in the developing.
I shoot HP5+ at 200, but I develop it for the recommended time for 400. I do this because for the way I shoot, with the cameras I use, it gives me a fuller tonal range and a look that I like.

I test every film that I use to find the ISO that works best for me. Some are close to the manufacturer rating, some aren't. I don't worry so much about 1/3 or even 1/2 stops, because most of my lenses only have full stops. But there is a difference, and it might matter, or it might not.
It does to me, but it doesn't to a lot of people. YMMV.
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Old 05-09-2008   #11
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NB23, yes, I'll like them over developed, but that is me. I just don't like the blocked shadows that you see so much on the web. I don't develop so much that the highlights are blown. And no to whoever asked I don't do compensating development. You can do compensating development with HC-110 and Rodinal, the two developers that I am using now, but these are not images done that way.

Nice photos Lynn and Wray.

Keith, you do it if you test and you're testing to get a certain shadow detail (without blown highlights). It is the only way to arrive at the time/temp/agitation that works best for you.

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Old 05-09-2008   #12
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I used to expose 400 ISO rated film at 320 (1/3 stop over) and developed for 400 ISO. This way I was more on the safe side when using a hand held meter at night (having some bright light sources and otherwise lots of dark areas in the frame) With the M6 (and Hexar), I found that exposure is more accurate (and consistent) so I set to 400 ISO.
About developing ... to many variables to keep it consistent when "home-developing". Making repeatedly a solution of an exact concentration is already at laboratory (with exact balances and graduated cylinders) a difficult task and this is only one requirement (agitation, constant temperature are additional erratic factors).
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Old 05-09-2008   #13
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Ray,

I firmly believe shooting 320 instead of 400 would show no real difference in real life. Same as shooting Plus-X 125 at 100. I often forget to adjust ISO settings and end up mixing up the ones I rated at ISO 125 and 100. Once developed, there is no way I can differentiate them. That's mainly because of the case by case metering for each shot as well as the different cameras I use as well as the shutter speeds probably reacting differently from shot to shot.

However, ISO 200 is very far from 1/3 stop difference, and I find this interesting. Your shot is on the lighter side with good contrast.
One thing all of us noticed is Kodak's stupid way of updating their films over the years. Like the old Tri-X 320 becoming the new 400 and a change in developing times which is seriously underrated. If people would follow Kodak's instructions they'd all end up with unusable underdeveloped negatives. The funniest part is they recommend the same developing times for TriX 400 and 800 (same for Plus-X 125 and 250). They claim the film's dynamic range is within the developing time tolerance. That's unbelievable and it drove me to test a whole 100ft roll rated at 100, 200 and 400 with HC110 with different dilutions. I came to a personal conclusion that ISO 400 was valid but the developing times needed to be prolonged.
Kodak's erroneous developing times is well documented all over photo.net.

Still, your shot looks good...
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Old 05-09-2008   #14
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Ned, I have to agree that a 1/3 of a stop is so narrow as to be within metering error of measurement! When you say lighter, are you referring to the midtones? Everything is there from pure black to white. The odd thing is that now I prefer a little more contrast to my images!
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Old 05-09-2008   #15
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Quote:
Originally Posted by NB23 View Post
Based on the premises that:

If it is true that a film's ISO rating is an estimate...
Dear Ned,

You are of course absolutely right that an awful lot of people look for a precision which is not only absent, but impossible to achieve. You are also absolutely right that in many pictures, quite grievous overexposure and a certain degree of underexposure can be corrected at the printing stage.

On the other hand there are a few points I'd like to challenge.

First, it's not true that ISO speeds are an estimate. They are a compromise (for the reasons given below) but they are also fully replicable, which stops them being estimates. And they vary with developers. HP5, for example, is a good ISO 650 in Microphen and maybe ISO 250 in Perceptol.

Second, the losses in quality with over- and under-exposure are very different.

With a conventional film, increased exposure leads to reduced sharpness and bigger grain in direct proportion to the overexposure. With a colour neg or chromogenic B+W film, 'grain' (dye cloud) actually gets finer.

The loss in ultimate sharpness can be significant; an extra stop can drop resolution from 80 lp/mm or better to 65 lp/mm or worse. Those are actual figures from when I was reviewing a new film for a magazine a few years ago.

Decreased exposure has the opposite effect, but sooner or later, quality falls off the edge of a cliff: empty shadows, lousy tonality.

The ISO standard is therefore a compromise to give good tonality along with the best sharpness and minimum grain achievable with that tonality. It also incorporates a small safety margin against underexposure; until 1959-60 the ASA standard had a full extra stop of safety margin.

Most in-camera meters are designed to give optimum exposure with slide films (exposure keyed to highlights) and will therefore underexpose negatives of subjects with a long subjecy brightness range (exposure keyed to shadows). This is an encouragement to rate neg films slower than they are. With a 1 degree true spot meter, I find I can rate films at or very close to their true ISO speeds. But hand the same meter to ten different people and ask them to meter the same scene, and you'll likely find up to a stop difference between their readings.

Conversely, few shutters run fast, and many run slow, which gives the film more exposure. One of my old Pentaxes is a full stop slow at most of the useful speeds, so I could rate ISO 400 at EI 800.

Many people prefer the tonality with a small amount of extra exposure: 1/3 stop, 1/2 stop, 2/3 stop. This gives a starting point.

As a result of all this, I would say that yes, 1/3 stop or 1/2 stop changes are worth worrying about, but only as a starting point.

In other words, if I set the meter on my MP at 125 when shooting Fomapan 200 (true ISO about 180 in the developer I use), then even after allowing for cumulative errors and my own metering technique, preferences, etc., I will get better pictures, on average, than if I set it at 160 and significantly more good pictures than if I set 200. I could equally well set 100 but then I'd be losing more sharpness than I need to and I'd be getting more grain.

A couple of references from my site that some may find interesting, on ISO speeds and subject brightness ranges, are:

http://www.rogerandfrances.com/photo...%20speeds.html

http://www.rogerandfrances.com/photo...s%20range.html

Cheers,

Roger

Last edited by Roger Hicks : 05-09-2008 at 23:16.
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Old 05-09-2008   #16
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Dear Roger,

I have one question now, when you slightly over exposure a film (1/3 stop for example), do you develop this film according to its "true" speed or the actual speed ?

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Old 05-09-2008   #17
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Quote:
Originally Posted by maddoc View Post
I have one question now, when you slightly over exposure a film (1/3 stop for example), do you develop this film according to its "true" speed or the actual speed ?
Dear Gabor,

These are in effect completely different questions, and well illustrate the truth of what Ned says.

I develop films so that the majority of negatives on a roll print well on grade 2-3. This is a simple iterative process. If you find yourself needing 3-4-5 all the time, you are under-developing; increase your development time (in 30 second or 1 minute increments) until most go onto 2-3. Likewise, if you need 0-1-2 all the time, you are overdeveloping and need to cut dev times.

If I scanned, instead of making what I persist in regarding as 'real' prints, I'd cut dev time to give a thinner neg with smaller grain, and adjust contrast in Photoshop -- but as I regard the vast majority of inkjet prints (unless made with specialist ink sets, especially Piezography) as grossly inferior to real ones, I'm not the best person to ask.

The above is for conventional monochrome neg only. With colour neg or chromogenic, the standard processing time is fine.

To answer a couple of questions you didn't ask, but many do (for the benefit of lurkers), there is a significant difference between overexposure and 'pulling' or reducing development time. The latter has far less effect on film speed (the speed point, 0,10 above fb+f) than most people think, but it does give you a low contrast negative. This may suit subjects with a long subject brightness range but for normal subjects it's a pain in the bum because you have to use hard paper to compensate.

Hope this helps,

Cheers,

Roger
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Old 05-10-2008   #18
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Dear Roger,

thank you a lot for the information. It helped a lot for sure.

Cheers,

Gabor
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Old 05-10-2008   #19
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I was going to give a confused explanation of the relation between a reflected-light reading and what was really going on in the scene regarding shadow areas, but thankfully Roger came along.

I would say that precise and repeatable "home" processing conditions are, in my opinion, certainly achievable regarding the usual variables time, temperature, agitation and chemicals mixing. The only thing which could be tricky in some parts of the world is the water quality - and that may not be consistent from day to day. In that case you will probably know about it already (especially if you drink the stuff) and mix developer with distilled water of some sort. There is no need to have magical darkroom equipment to achieve consistency !
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Old 05-10-2008   #20
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One more thing to add is that while ISO films speeds are replicable, they are not always the speed that will suit a particular photographer best, which is why they are recommended as starting points. All manufacturers tell you to make adjustments based on your own needs -- adjustments that are necessitated by the variables Ned lists, and more.

Exactly the same is true of dev times: the manufacturers advise you to change them as needed, in order to get negs of your subjects, shot with your kit, that print the way you like.

At this point it is easy to attack the manufacturers for giving wrong speeds or dev times but it is important to remember that ISO speeds are the best we have, and the best we have ever had -- far better than the days when film speeds were set by the marketing department. Generally, too, the manufacturers' dev times are the best starting point: far better than the maunderings of a self-appointed expert.

When I started out, I always felt I was doing something wrong if I didn't stick slavishly to the ISO (in those days, ASA) speeds and manufacturers' dev times. Realizing that they meant what they said, and that both ISO speeds and dev times are starting points and nothing more, was an enormous liberation.

Cheers,

Roger

Last edited by Roger Hicks : 05-10-2008 at 03:52. Reason: typos
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Old 05-10-2008   #21
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Quote:
Originally Posted by MartinP View Post
I was going to give a confused explanation of the relation between a reflected-light reading and what was really going on in the scene regarding shadow areas, but thankfully Roger came along.

I would say that precise and repeatable "home" processing conditions are, in my opinion, certainly achievable regarding the usual variables time, temperature, agitation and chemicals mixing. The only thing which could be tricky in some parts of the world is the water quality - and that may not be consistent from day to day. In that case you will probably know about it already (especially if you drink the stuff) and mix developer with distilled water of some sort. There is no need to have magical darkroom equipment to achieve consistency !
As I read down the thread, I was trying to remember all that I used to know about exposure and development. Silly me! I should have known that Mr. Hicks would chime in and give a lot more and more correct information that I could have. Thank you Mr. Hicks. It was enlightening to me too.
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Old 05-10-2008   #22
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Indeed, the difference is lost in the "noise" i.e. the inconsistency of the metering, development, etc.
BUT
the noise is centered around a alue. This value is the EI you are using.
It can be centered at iso 400 or iso 320 - and this might slightly matter, on a scale that statistically makes sense(i.e. thousands of films).

So i went for no because, what usually happens is, people advise others to expose the e.g. C41 black and white films at iso 320 instead of 400, because that seems to work for themselves (or because so they've read on internet). This is a worthless advice unless they KNOW how you meter, how you develop etc.

Finally, for c41 film, 1/3 stop hardly matters, even if you are 100% consistent. For slide, it might make a difference.
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Old 05-10-2008   #23
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What a great thread!
Thank you, Roger, for your easy to understand explanation.
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Old 05-10-2008   #24
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Warm up that dustcloud where you keep your developer, skibeerr
Or shake it a bit more.
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Old 05-10-2008   #25
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Quote:
Originally Posted by skibeerr View Post
I have not yet experimented, if I want to try in wich direction should I go?

Your own. Most people just randomly tweak around with a variety of settings garnered from manufacturers, websites, internet forums etc. But that just leads to the circumstance NB23 is pointing out. Way too many variables and you don't know if they are canceling each other out.

Few people standardize and test their own because that is more difficult than getting it off RFF. So, I'd say understand the theory behind basic sensitometry and test and standardize on your own for your workflow. That is what I do. Test for my own EI and development time for the density range best suited to my enlarger and plan out the developing process precisely so it is as repeatable as possible.
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Old 05-10-2008   #26
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Quote:
Originally Posted by crawdiddy View Post
I have been vaguely aware that some posters here seem to advocate such processing. I'm not sure what the point is. To me that's the same as shooting a frame at 1/3 overexposure, except you're doing it to the entire roll. To me, underexposure, or overexposure is a decision I make for an individual shot.

I deliberately overexpose to 1/3-1/2 films like 400CN or XP2.
but it's matter of taste. most C-41 films look too "gray-ish" for me
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Old 05-10-2008   #27
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Quote:
Originally Posted by skibeerr View Post
I try to do everything according to the kodak, Ilford, rollei book and get realy flat negatives.
I have not yet experimented, if I want to try in wich direction should I go?
Increase dev time 30% (Roll 1).

If that's too contrasty for you, halve the increase next time (Roll 2).

On the roll after that (Roll 3), go up or down as you think fit. Three rolls should see it.

Are you scanning or wet printing?

Cheers,

R.
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Old 05-10-2008   #28
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With only full stops in shutter speed and aperture setting possible on my meterless FED2.... I guess I have to say "I don't really care"

Exposing for ISO 320 turns out to be quite exactly the same as for ISO 200 ... or as 250 ... which happens to fit my sunny f16-meter

But I'm currently shooting C41 so that may all change when my darkroom has been rebuilt


(oh sure i can set the aperture between two clicks on those old Russian lenses, but seeing how a half or third stop are not located halfway or a third of the way between two stops, this is just guesstimation, too)
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Old 05-10-2008   #29
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Yes, thanks Roger, I remember those slavish days, too. David Vestal was the first guy I read that suggested finding your own numbers. That suggestion was even greeted with suspicion.
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Old 05-10-2008   #30
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Quote:
Originally Posted by skibeerr View Post
I am learning to print wet.

Kind regards,
Wim
Dear Wim,

Great!

It's much easier that way.

Harder in the (very) short term.

Easier (especially for negative evaluation) in the less short term.

Cheers,

R.
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Old 05-11-2008   #31
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Old 05-20-2008   #32
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Do you really believe in exposing at iso 320?

I believe it. I've seen it happen.
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Old 01-10-2009   #33
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i do it for a different reason. Negs have a lot more latitude for overexposure but less for under exposure so over exposing it at 1/3 stop is sort of erring on the side of caution. If its properly exposed, than the extra 1/3 will not make any difference but if i have metered a scene wrong and underexpose it, the extra 1/3 might just save me some shadow detail. Granted its not much, but it'll be something.
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Old 01-10-2009   #34
philipp.leser
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I think it's useful to test and measure your process at one point, because then all the not-quite-intented variations that do happen will at least vary around a point which was determined to be good.

I try to limit myself to only one or two developers and a very small selections of film, so I can really understand the process. It starts with making a few test shots a different exposures from zone 1 to 10 maybe, or even more if I feel like it.

I then develop and measure the log density of the negatives. The right speed of the film in the given developer is reached when zone 1 has a log density of 0.10 over fog and base. That is a very easy measurement!

The second important point is the contrast, which is determined by the development time (I use Diafine a lot, so using that developer it's not a variable). Just vary the development time so the negative has an copying range that fits a medium filter for your given paper and paper developer (which for me is around ISO R 70-80).

This might sound complicated, but it really is not, takes only one or two rolls of film and stays correct as long as you don't change your developers and film types every day.

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Old 01-10-2009   #35
marke
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Didn't Kodak's originally rate Tri-X 400 at 200?
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Old 01-10-2009   #36
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Quote:
Originally Posted by marke View Post
Didn't Kodak's originally rate Tri-X 400 at 200?
Yeah, then they spawned a "Leap of Faith" 320 version
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Old 01-10-2009   #37
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I believe the only correct answer to 99.9% of all photo related questions is "it depends".
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Old 01-10-2009   #38
Al Kaplan
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In the early 1960's the ASA of all films, with a few exeptions, was doubled. Tri-X jumped from 200 to 400, but that still left about 1/3 stop safety factor. More puzzling was when ISO took over at first they listed both the ASA number followed by the German DIN number so Tri-X became ISO 400/27, then a few years later they dropped the DIN number. Yet DIN speeds are not directly comparable to ASA speeds. ASA sets speed by density part way up the straight line portion of the H&D curve while DIN measures density from a point above the base density of the developed film. In other words DIN is measuring minimum shadow density while ASA is measuring the speed of the mid tones. In the end you have to shoot your own tests with your brand of metering technique and your soup and and your agitation regimin. Have fun.

Professional Tri-X 320 is a whole 'nother ball of wax. It has a different spectral response, and the contrast, highlight and shadow rendering are optimized for studio portraiture. I don't think it's ever been marketed in 35mm, just 120/220 and sheet film. It also has (or had) a slight retouching "tooth" on the surface for pencil retouching. It doesn't push well either.
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Old 01-10-2009   #39
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small things add up. If I am getting a speed of 320 with a certain film (and it is not hard after VERY simple snap happy testing to be sure of this) then I will use it as this speed. I would be silly to use it at anything else -right? 1/3 of a stop can make a lot of difference if a neg is on the edge of having no shadow detail or on the edge of being blown beyond rescue with super hot highlights. The prob of not doing this is that if you shoot a film that is making 320 with your set up at 400 and then underexpose by 1/3 stop for what you were hoping to get in the shadows, you are now 2/3 of a stop under-done. Same thing could make life VERY tough in the darkroom for overexposure.

if a film is making 320 it is making 320. It is impossible to claim that this makes no difference because it can be proven quite simply that it does...it makes 1/3 stop difference. 1/3 stop can make the difference between something in complete silhouette and faint detail that lift it from the 2-dimensional. Film speed is not magic and it is not hearsay. It is a real measurable and testable thing and we all agree that proper exposure matters, right?

I went back to basics recently and did some fresh tests on 4 films before a trip to India, including with filters to nail down MY filter facors (which were appreciably out from the manufacturers as it turned out). I decided on 320 with several of them with my Mamiya 7. The result was some negs that were less than ideal but literally none that were a major problem. Had I gone 1/3 stop in either direction that would have increased my prolbem with hot highlights or thin shadows appreciably in a number of negs. Why use anything else if 320 is right? Its like using the wrong spanner when you have the right one sitting in front of you!

PS. There is no point worrying about 1/3 stops if you have not done filter tests, esp if not using TTL metering and having to apply the factor manually. I got + 1/3 with my yellow (listed as +1) and +1 1/3 or 1 1/2 with my orange (listed as 2). start by nailing down the film speed minus filters, then work out filter factors and before you know it you nail your exposures.... no more guesswork and you can concentrate on shooting confidently. It is worth noting that i found the 'real world' tests on filter factors agreed with those done against a lightbox with 3 different cameras agreeing on the factor even though they differed in their indicated base exposure. Its all about what actually works for you. I can see with my own eyes that X exposure is better than Y even when the difference is only 1/3 stop. If I can see that 1/3 stop difference what possible reason would I have for not applying it?

Last edited by Turtle : 01-10-2009 at 10:33.
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Old 01-13-2011   #40
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(I'm a bit late to this party, but here goes.) Every single answer in this thread seems quite valid to me. So I have only this one comment, which addresses the question of all those potential errors NB23 named. They are errors that could be cumulative, all adding up in one direction. Or, they could partially or completely cancel each other. So how to deal with all these unknowns when shooting?

Of course, the best way is to establish habits through testing and experience. That's already been said here, in a number of different posts. Here's another thought.

An old navigator's trick is to deliberately fly to the left of the destination. Harold Gatty knew that if he did that, he could count on the destination being somewhat to the right. Gatty was the navigator for Wiley Post, the first pilot to fly around the world in 8 days.

Now, what if I don't know how some variables will add up, and i want to make sure I get enough shadow detail? If I add one or two third-stop increments to my exposure, I know that I have erred on the side of more shadow detail. I'm flying to the left. Other posters have already talked about erring on the side of caution, so this is just a different way of saying it.

In practice, the extra exposure gets me a little more shadow detail, and it also lets me reduce my development to control contrast. That way, I can put behind me the days of blocked-up highlights I couldn't punch through with a laser beam. At times when contrast is too low, that's what contrast filters are for.

Tri-X at EI 250, developed in D-76 1:1 for 7 minutes is pretty foolproof on a harshly sunlit summer day. It's like an insurance policy against disappointment.
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