Need help using zone system with film with 19-stop dynamic range

[peterB1966]

Hi, I am an experienced digital photog making an excursion into medium format analogue, and due to the cost of film and processing over here, am hoping to use the zone system to get myself shooting okayish photos pretty quickly and consistently.

Today I was given Kodak's 120 Tmax to try out, and when I Googled I found that the dynamic range is 19 stops!

How the heck do you use the zone system on that?

Does one:

• Continue (generally) using three stops in either direction off middle grey (and assume the rest is just latitude for when you want to push the film, which I understand to mean shooting e.g. at 800iso even though it is 100iso)

or:

• Do I need to convert the zone system for a 19 stop range, i.e. a zone now is the equivalent of just under two stops, and I now have a range of approx. 5 stops either side of middle grey?

Much appreciated!

 

[Bill Burk]

The film can handle that much range but you will never need it all.**

Do everything you would normally do.

Zone System is a good way to plan how you will expose and develop film.

Because of the nature of Zone System metering, when you test you will find the speed 2/3 stop (2 ASA marks) lower than rated box speed.

So you can start there, 2/3 stop less than box speed when you are metering with spotmeter and placing shadow readings at Zone III or Zone II. You can sanity check with an incident meter set to the rated ASA box speed - the f/stops and shutter speeds should be close. You may anticipate 2/3 stop difference in readings between Zone System and Incident metering. But they should be close to each other if the meter is set 2/3 stop lower for Zone System. And that will be the correct exposure.

Many people simply leave their meter set to 2/3 stop less than box speed no matter which way they meter regardless of the slight overexposure. It is a situation where nobody is really that precise anyway and slightly greater exposure is OK

**But if you want to take pictures of flowing water you may use a shutter speed of one second even in daylight without having to get neutral density filters because the film will hold detail in extreme overexposure. You may have to experiment if you plan that kind of thing. But the film can take it.

 

[peterB1966]

The film can handle that much range but you will never need it all.**

Do everything you would normally do.

Wow, amped to get such a fast reply, as I am champing to get shooting - thanks, Bill!

The other information is also pretty thought-provoking, wrt how forgiving it is of the slow shutter-induced over-exposure.

So if I get it right, I will still get the proper contrast / dynamic range in my result if I use the 1 stop per zone system, but in instances where e.g. I would normally be clipped (to use a digital term), I will benefit form the higher dynamic range by being able to pull/recover information when processing?

 

[peterB1966]

...Will you be printing these negatives in a darkroom or scanning them and processing/editing in software?

Thanks for what looks like sound advice.

I will not be printing them myself, but the aim is to get to the stage where I can select successful ones for high res scanning and processing digitally (but until then it will be as it comes out from the lab). Would I still be able to get the info that this film records though it falls outside of the 11-zone parameters if I scanned and processed, or does it become restricted by that stage due to digitisation?

 

[Bill Burk]

With film, Color Slide film acts like digital with respect to clipping.

With black and white negative film, any “clipping” happens at the shadow side.

That’s why it’s better to give slightly more than perfect exposure.

Much greater exposure is fine, with some degradation in the qualities that make the best possible picture... but lets you get away with things like this:


This picture was taken with camera on B for as long as my daughter’s foot was on the ground- careless long time exposure.

Pedestrian's Foot, Slug Bug 2

• Bill Burk
• Aug 22, 2012
• 8

Re-creation of Otto Steinert's effect to illustrate thread Pedestrian's Foot

 

[Alex Benjamin]

High dynamic range mostly means that you'll have more chance having details in shadow areas (zones II, III & IV) and highlights (zone (VI, VII, VIII). Remember that no matter what the film range may be, middle grey will always be middle gray, pure black will always be pure black, pure white will always be pure white.

In other words, it's your metering that counts, not the film's range. As michael_r mentioned, meter the scene, check middle grey, see where you want to put your shadows (whether or not you want details in them), see where the highlights fall (checking if you want details in them), and shoot.

You'll have to experiment anyway, since type of developer and development technique will affect all this anyway.

 

[peterB1966]

...it’s better to give slightly more than perfect exposure...

Ok, so now I have to ask what is meant by the above line: it implies "to over-expose" but if it clips on the black side, surely it would be better to under-expose a bit? You spoke earlier about 2/3 stop less than the box speed... does that mean e.g. iso 400 would come down to below 300, i.e. slower film hence 2/3 stop less exposed than the box suggestion?

 

[Sirius Glass]

Thanks for what looks like sound advice.

I will not be printing them myself, but the aim is to get to the stage where I can select successful ones for high res scanning and processing digitally (but until then it will be as it comes out from the lab). Would I still be able to get the info that this film records though it falls outside of the 11-zone parameters if I scanned and processed, or does it become restricted by that stage due to digitisation?

I use box speed and then use the Zone System to bring out the shadow details and develop normally. Since you are not printing the photographs yourself, that will work well. Modern films no longer require changing the development times.

 

[MattKing]

Ok, so now I have to ask what is meant by the above line: it implies "to over-expose" but if it clips on the black side, surely it would be better to under-expose a bit? You spoke earlier about 2/3 stop less than the box speed... does that mean e.g. iso 400 would come down to below 300, i.e. slower film hence 2/3 stop less exposed than the box suggestion?

Bill's reference to clipping is a reference to losing detail in general, not over-exposing.
T-Max films have a very good capacity to retain detail in the highlight areas. Most negative films do - T-Max films are just very good at that.
All negative films have a limited capacity to retain details in shadow areas.
The Zone system's approach emphasizes the steps that protect from loss of detail in that portion of the shadow areas where details matter. It was also designed in an era when printing options were somewhat more demanding.
The way that you measure speed in a Zone system environment returns a speed that is 2/3 of a stop less than if you measure speed using the box or ISO speed method, so ISO 400 film will generally work out to have a Zone system EI of 250.
If you use Zone system methodology, there is an inherent assumption that you will further manipulate the results at the developing and printing or post processing stage.
If you use ISO based methodology, any "proof" or machine prints that come from the lab will probably look better than the ones from Zone system negatives, because the ISO approach yields more attractive mid-tones and highlights in un-manipulated prints, and it is the appearance of mid-tones and highlights that tend to have the greatest affect on viewers.
Most importantly though, don't get hung up on the 19 stop figure. Expose to make sure that you both retain any desired and useful shadow detail, and place mid-tones in a useful place. If the dynamic range of the subject is very narrow, you may wish to change development in order to expand the range of the result. I normally don't adjust development to contract a wide dynamic range subject, as I prefer to do that at the printing stage. In most cases, it is the appearance of the mid-tones that matter most to me.

 

[Alex Benjamin]

I use box speed and then use the Zone System to bring out the shadow details and develop normally. Since you are not printing the photographs yourself, that will work well. Modern films no longer require changing the development times.

I totally agree with Sirius Glass. If you're just starting with the Zone system, keep it simple. Use box speed, meter, make sure your shadows (Zone III and IV) have details, and develop normally.

That will give you the basics from which you'll be able to experiment later on - like learning your basic scales and modes in jazz. Once that's set (honestly, proper zone placement isn't as easy as it sounds and it does take practice to get it right), you can add different parameters (changing the ASA, different types developers, etc.). If you put too many variables from the start, it'll just get confusing.

 

[Bill Burk]

MattKing’s answer is what I would have said. I use 400TMAX at 250 and 100TMAX at 64.

When you give overexposure to black and white negatives you “put more detail” in the material.

When you print, you “have more information to work with”. The procedure of printing is a second opportunity to adjust brightness and contrast.

 

[Alan Edward Klein]

Thanks for what looks like sound advice.

I will not be printing them myself, but the aim is to get to the stage where I can select successful ones for high res scanning and processing digitally (but until then it will be as it comes out from the lab). Would I still be able to get the info that this film records though it falls outside of the 11-zone parameters if I scanned and processed, or does it become restricted by that stage due to digitisation?

I don;t do my own printing or processing. I scan my film with my own scanner. I shoot at box speed. Here are Tmax 100 samples. https://www.flickr.com/search/?sort...&tags=tmax100&user_id=55760757@N05&view_all=1

Why do you want to use the zone system if you're not processing or printing but scanning?

 

[peterB1966]

I don;t do my own printing or processing. I scan my film with my own scanner. I shoot at box speed. Here are Tmax 100 samples. https://www.flickr.com/search/?sort=date-taken-desc&safe_search=1&tags=tmax100&user_id=55760757@N05&view_all=1

Why do you want to use the zone system if you're not processing or printing but scanning?

initially, because it gives me a consistent approach against which to quantify the results. Else I am just guessing what went right and what went wrong.
And then in the end because when I scan, it will be with the intention of digitally processing and printing.

 

[peterB1966]

The way that you measure speed in a Zone system environment returns a speed that is 2/3 of a stop less than if you measure speed using the box or ISO speed method, so ISO 400 film will generally work out to have a Zone system EI of 250.

The way that you measure speed in a Zone system environment returns a speed that is 2/3 of a stop less than if you measure speed using the box or ISO speed method, so ISO 400 film will generally work out to have a Zone system EI of 250.

Does that mean that even middle grey, on the zone system, should b 2/3 stop less? (I ask because it seems to be counter-intuitive?)

 

[grain elevator]

and I now have a range of approx. 5 stops either side of middle grey?
Much appreciated!

Although it can be read from other posts, but no-one has yet explicitly objected to this notion of symmetry in dynamic range, and it also occurs in the posting below:

High dynamic range mostly means that you'll have more chance having details in shadow areas (zones II, III & IV) and highlights (zone (VI, VII, VIII). Remember that no matter what the film range may be, middle grey will always be middle gray, pure black will always be pure black, pure white will always be pure white.

I don't think this is entirely correct. Higher dynamic range does not per se impact shadow detail with negative film, because the ISO standard is essentially a measure of shadow detail. I.e. dynamic range downwards of middle gray is cancelled out as long as you stick more or less to the ISO rating. So yes, pure black is pure black, however there is, under reasonable conditions, no such thing as pure white (pure black on the negative) - because the dynamic range towards highlights is huge, and they can be extracted in printing or (scanner permitting) in scanning.

 

[cowanw]

Ok, so now I have to ask what is meant by the above line: it implies "to over-expose" but if it clips on the black side, surely it would be better to under-expose a bit? You spoke earlier about 2/3 stop less than the box speed... does that mean e.g. iso 400 would come down to below 300, i.e. slower film hence 2/3 stop less exposed than the box suggestion?

Just to make the point that lowering the ISO means you will increase shutter speed or Fstop for a given scene to result in more exposure

 

[radiant]

initially, because it gives me a consistent approach against which to quantify the results. Else I am just guessing what went right and what went wrong.
And then in the end because when I scan, it will be with the intention of digitally processing and printing.

I guess you mean you just want to expose correctly rather than use the actual zone system? Without compensating the development time you are missing the most important part. Like leaving the work half done.

If you are using Tmax films, there is nothing to worry about. Just overexpose and you are fine. You only need to worry about shadows so easiest way is to overexpose for example 1-2 stops and you should have all the details you ever need.

 

[Alex Benjamin]

Although it can be read from other posts, but no-one has yet explicitly objected to this notion of symmetry in dynamic range, and it also occurs in the posting below:

I don't think this is entirely correct. Higher dynamic range does not per se impact shadow detail with negative film, because the ISO standard is essentially a measure of shadow detail. I.e. dynamic range downwards of middle gray is cancelled out as long as you stick more or less to the ISO rating. So yes, pure black is pure black, however there is, under reasonable conditions, no such thing as pure white (pure black on the negative) - because the dynamic range towards highlights is huge, and they can be extracted in printing or (scanner permitting) in scanning.

I agree. My point referred to looking at it from the point of view of the zone system, not from that of the dynamic range of the film. I see the zone system much like equal temperament in music. You play a chromatic scale on a piano - from C to C - and you get twelve note equally distant of the same semi-tone. It's a practical and useful compromise, it allows different instruments to play together, but it has little to do with the actual dynamic range of tones between the octave. Many composers have exploited that range in microtonal music (notably in electronic music) - and you also find examples in various non-classical music (Indian raga, for example).

 

[Bill Burk]

Does that mean that even middle grey, on the zone system, should b 2/3 stop less? (I ask because it seems to be counter-intuitive?)

You know how everyone says the meter only sees middle gray?

In the Zone System, middle gray is “defined” as Zone V. Zone System tests look for 0.10 density above base+fog at Zone I.

In the ASA/ISO system middle gray works out to be 10 times the same point.

The difference between “four stops” and “times ten” is this 2/3 stops I am talking about.

 

[Bill Burk]

Forgive me for occasionally confusing “Zone System” index 2/3 stop with general advice to choose 2/3 stop as a preference to give slightly more exposure.

Zone System 2/3 stop adjustment + Zone System metering should give same exposure as Box Speed + incident metering

Choosing 2/3 stop adjustment + incident metering should give slightly greater exposure to the negative that you print down. The additional information in the shadows may or may not ever be seen by viewer. If there was something important you could reveal it.

I set my speed to 2/3 stop adjustment for both reasons at the same time.

I like Zone System metering. I know the exposure will be right. I am too lazy to decide metering in advance so I might put the camera in automatic and get the slightly increased exposure that I like anyway.

When it gets darker and I still want to handhold I will nudge the compensation to zero. I might even nudge it a little more as it gets even darker.

So I think about all this seamlessly, and I keep in mind why. But I often forget that Zone System metering isn’t supposed to give you greater exposure. It’s supposed to give you perfect exposure

 

[Bill Burk]

Of course there is the question: How do you take and place shadow meter readings in Zone System?

Reading:
a. Walk up close to the subject, read the darkest spot
b. Stand at camera position and read the darkest spot

Placement:
1. Place on Zone II
2. Place on Zone III

I believe a.1. (Minor White 1964) and b.2. (Ansel Adams 1981) will give different meter readings but when placed the result will be the same combination of f/stops and shutter speeds.

And (with Zone System having had the 2/3 stop adjustment), both a.1. and b.2. should agree with Incident metering at Box speed (for a normal subject luminance range subject).

 

[bluechromis]

As others have alluded, the bottleneck of dynamic range in your workflow is likely to be the scanner. Adox Silvermax 100, for example, was a film promoted to have a wide dynamic range. Some people said that their scanner was incapable of capturing all that in a single pass. So they resorted to making multiple scans of a negative and digitally merging them. This why people often go for a flatter negative when will be scanned. This may be tricky when using a lab to do the scanning. When you get back the scanned images, and there is a loss of detail at high or low end, there is the question of whether the detail was never recorded by the negative or whether was lost in the scanning process. You might be able to examine the negatives with a loupe and see if the detail is there. In any case, the scanning process can have big impact on final result so you want to become knowledgeable about it.

 

[MattKing]

Reading:
a. Walk up close to the subject, read the darkest spot
b. Stand at camera position and read the darkest spot

Just to emphasize, when you read this, it is really important to remember that "darkest spot" should be read as "darkest spot which has detail that you need to record".
There is a temptation to take that reading off the part of the scene that is the darkest overall. Don't give in to that temptation.
The same consideration applies to highlights.

Does that mean that even middle grey, on the zone system, should b 2/3 stop less? (I ask because it seems to be counter-intuitive?)

Actually, 2/3 stop more, because if the film speed is 2/3 stop less, the meter reading will result in you giving the film 2/3 of a stop more light.
If you use a Zone System approach, the extra exposure will give you negatives that are more dense. And your Zone 5 will be denser on the negative.

 

[Lachlan Young]

As others have alluded, the bottleneck of dynamic range in your workflow is likely to be the scanner. Adox Silvermax 100, for example, was a film promoted to have a wide dynamic range. Some people said that their scanner was incapable of capturing all that in a single pass. So they resorted to making multiple scans of a negative and digitally merging them. This why people often go for a flatter negative when will be scanned. This may be tricky when using a lab to do the scanning. When you get back the scanned images, and there is a loss of detail at high or low end, there is the question of whether the detail was never recorded by the negative or whether was lost in the scanning process. You might be able to examine the negatives with a loupe and see if the detail is there. In any case, the scanning process can have big impact on final result so you want to become knowledgeable about it.

What you are describing are operator errors/ lack of knowledge about what the scanner's bit depth & software are doing, not necessarily inherent scanner problems. Even your average CMOS camera sensor can largely (I'd say all current sensors, but there may be exceptions) pick up the entirety of the useful dynamic range in a BW negative in a single shot without problems - it's then up to the end user how to (hopefully intelligently) invert that & make tonal corrections. You should never, ever compromise a negative for scanning. Indeed, a lot of the nonsense about the supposedly 'huge' dynamic range from scans came from people realising they could scrape a bit more from stuff in the toe/ shoulder when using decently high end scanning solutions that were comfortably able to get every last bit of resolved latitude information (note: not 'all' information - there is a difference between resolved information contained on the film, and resolution of film structure information, and this is a problem that scanning seems to have never quite managed to understand, let alone tackle really convincingly) out of a film in a linear-ish fashion that might have needed complex darkroom masking procedures to otherwise retrieve.

 

[removed account4]

Today I was given Kodak's 120 Tmax to try out, and when I Googled I found that the dynamic range is 19 stops!

good luck with your project, just remember silver bullets are only good for therewolves