"Expose for Shadows, Develop for Highlights"

[Chriscrawfordphoto]

I'd like to clarify one thing (and Roger, you can correct me if this is wrong).

For a given film and developer and working method, there is a correct EI. Technically the EI doesn't change for differing scene contrast or dev. time. When we say that we change the EI (like when I said shoot tri-x at 200), we are really just talking about a way to get the shadows exposed properly when using average metering or sunny 16 type rules of thumb. If you were metering the shadows with a spot meter, I don't think the EI would change.

Cheers,
Gary

Its wrong. A shorter developing time does lower film's effective speed, even when metering the shadows with a spotmeter. I do it all the time and have scientifically tested using a densitometer. On most films, you lose a full stop of speed when developing time is reduced 20-30%

Lengthening developing doesn't raise speed much with most films, just 1/3 to 1/2 stop and some developers are better for that than others.

 

[Roger Hicks]

I'd like to clarify one thing (and Roger, you can correct me if this is wrong).

For a given film and developer and working method, there is a correct EI. Technically the EI doesn't change for differing scene contrast or dev. time. When we say that we change the EI (like when I said shoot tri-x at 200), we are really just talking about a way to get the shadows exposed properly when using average metering or sunny 16 type rules of thumb. If you were metering the shadows with a spot meter, I don't think the EI would change.

Cheers,
Gary

Dear Gary,

Well, sort of. The thing is that ISO specifies all conditions. EI (being a working speed) doesn't so much specify them as accommodate them.

A very great deal, when changing dev time in particular, depends on the shape of the characteristic curve. A long-toe film such as Delta 3200 will show greater variation in EI, and less in contrast, with varied development time, than a short-toe film such as Pan F.

As soon as you depart from ISO standards, spot metering becomes very empirical indeed. My own experience accords with yours: that effective EI, for usable shadow detail, changes a lot less than you might expect. But equally, I'm reasonably sure that Chris is correct if you stick with a fixed density criterion (instead of 'usable contrast') for speed.

Cheers,

R.

 

[xwhatsit]

So, with rollfilm, make these exposure adjustments -- different EIs on the same roll. Then develop for the normal time. Not as good as shooting all at the same EI and developing appropriately, but still better than shooting all at box speed and developing normally regardless of scene contrast. Have I got the right end of the stick?

It seems I do this to a limited degree anyway, when I use my Weston Master. It has the A and C marks for contrasty and flat scenes. Auckland is one of those changeable weather places; rain, bright sun, overcast all in a few hours.

 

[gns]

Roger, Chris,

So let's take 2 scenarios.

1. I'm looking at a pretty normal contrast scene. I get my spot meter and read the darkest area where I want detail. I take my reading and stop down 2 or 3 stops (whatever) and get an exposure of 1/250th of a second. I then read the lightes area where I want detail and determine that I will use normal development time. Done.

2. Now I have a contrasty situation. I do the same...read the shadow area,blah blah blah and come up with 1/250th of a second. Now I read the light area and see that I need to contract that down by one stop, so I decide to use a short dev. I do not however go back and change my exposure to 1/125th (change iso)because I'm shortening the development, do I? It seems to me that doing that would then push my light area up one more stop requiring a further contraction. Vicious circle?

Cheers,
Gary

 

[Juan Valdenebro]

It's true it's easier (talking about amounts) to "make" a film slower than making it faster, as Chris said.

It's true different films have different designs and curves and produce different results when we "displace" their EI for shorter and longer development times, as Roger said.

But it's also true that inside their curves, B&W films allow certain "movement" if we talk about EI and middle values (not only contrast and highlights), and even if shadow detail "speed" can't be considerably risen, there's room for placing values where the photographer wants up to a certain point (inside the working range of the curve) as Ansel Adams did with his zone system.

Thank God B&W films don't have an unique EI like color films, and thank God we can do a lot with planned development when it's related to proper exposure (and this includes variable EI for metering...)

I just developed the test roll, and it's getting dry... Sun scenes are fine, and soft light ones even at +2 are very flat, and whites are not reached on film... Maybe some things can be done while printing, though... Yet I have to print, but I'd say a better way to do it is using longer development for soft scenes, and I'll keep using two bodies at least... I think that system (giving more light to flat scenes with the same development time) works better for those developing sun scenes for longer times than I do: middle point development.

Cheers,

Juan

 

[Chriscrawfordphoto]

Roger, Chris,

So let's take 2 scenarios.

1. I'm looking at a pretty normal contrast scene. I get my spot meter and read the darkest area where I want detail. I take my reading and stop down 2 or 3 stops (whatever) and get an exposure of 1/250th of a second. I then read the lightes area where I want detail and determine that I will use normal development time. Done.

2. Now I have a contrasty situation. I do the same...read the shadow area,blah blah blah and come up with 1/250th of a second. Now I read the light area and see that I need to contract that down by one stop, so I decide to use a short dev. I do not however go back and change my exposure to 1/125th (change iso)because I'm shortening the development, do I? It seems to me that doing that would then push my light area up one more stop requiring a further contraction. Vicious circle?

Cheers,
Gary

Yes, you do need to give that extra stop of exposure if you want full shadow detail, and no it doesn't push the highlights back where they were. Test it, you'll see. Shorter developing time affects the bright tones more than the darks, so even with the added exposure to support the darks, the lights are still reduced

 

[tlitody]

Roger, Chris,

So let's take 2 scenarios.

1. I'm looking at a pretty normal contrast scene. I get my spot meter and read the darkest area where I want detail. I take my reading and stop down 2 or 3 stops (whatever) and get an exposure of 1/250th of a second. I then read the lightes area where I want detail and determine that I will use normal development time. Done.

2. Now I have a contrasty situation. I do the same...read the shadow area,blah blah blah and come up with 1/250th of a second. Now I read the light area and see that I need to contract that down by one stop, so I decide to use a short dev. I do not however go back and change my exposure to 1/125th (change iso)because I'm shortening the development, do I? It seems to me that doing that would then push my light area up one more stop requiring a further contraction. Vicious circle?

Cheers,
Gary

John Sexton said "It's a zone system, not a pinpoint system". That gives you half a stop either way latitude without ruining anything unless you want to get anal about it. If in doubt just over expose a little to be sure of not losing too much low value detail.

 

[Juan Valdenebro]

gns,

Why don't you test it yourself? Do you wet print?

The reason for saying this is the variables are a lot, and what you'll find will depend on many many things you'll do with your own shutters, your own meters, your own development, your own films, your own thermometer, etc... It's as unusual as winning the lottery to go and do anything anyone tells you and being able to get exactly the same conclusions and results... One thing is true, though: if you change exposure, you're placing your values inside film's curve just a bit differently, but you keep contrast unless you go too far (out of the curve), however if you change development, you're changing values a lot more than just with exposure, and here's where most people are lazy, and prefer not to develop the same scene for different times, so they never see how flexible films are... I wet print Tri-X exposed from 50 to 1600 incident, but this is not about EI: it's a lot more about different development times. But testing different development times with different scenes only, is like doing nothing...

Cheers,

Juan

 

[gns]

Chris,

If you increase exposure by one stop, then the light area which WAS one stop above where we wanted it, is now 2 stops above where we wanted. right? So now what do we do about development?

 

[Chriscrawfordphoto]

Chris,

If you increase exposure by one stop, then the light area which WAS one stop above where we wanted it, is now 2 stops above where we wanted. right? So now what do we do about development?

You reduce the developing time. With most films, one stop overexposure coupled with a 25% reduction in developing time will keep the dark tones at the same place they'd be with normal exposure and developing and will drop the light tones one stop lower than they'd have been with normal exposure and development.

 

[Juan Valdenebro]

You reduce the developing time. With most films, one stop overexposure coupled with a 25% reduction in developing time will keep the dark tones at the same place they'd be with normal exposure and developing and will drop the light tones one stop lower than they'd have been with normal exposure and development.

Hi Chris,

In general that's right if we talk about the ways things work, but it seems too precise for being true... It depends a lot on film's design as Roger said, and I'd say, also on developers: it doesn't happen the same way with Tri-X/Rodinal and TMax400/TMax developer, just to talk about two sets that behave differently, being the first one more permissive and the second one more critical...

Again, we're all saying the same in general...

Cheers,

Juan

 

[johannielscom]

Dear Johan,

So am I. I do only the easy bits, and if something takes too long, I don't do it. Photographically, I've always believed in 'shoot first and ask questions afterwards'.

It's almost certainly useful to know the theory behind what you're doing, but it's far from essential, so unless you're interested, or unless you're being paid to do it, it's not worth much investigation.

As Ade-oh points out, and as your own experience shows, a lot of people get altogether too excited about this sort of thing, and lose sight of making good pictures becase they're trapped in a morass of minutiae that often, they don't fully understand.

I'd lay odds that 99% of the time, I could use any of four different metering techniques (incident, spot, broad-area reflected, in-camera), and then arrive at much the same conclusion about the optimum exposure. About 80-90% of the time, if I guessed the exposure, it would be within 1/2 stop of the optimum exposure as metered, often spot on for the optimum.

In fact, I've noticed something REALLY weird lately with my Ms. Quite a few times, I've turned the shutter speed dial and aperture ring to roughly the rght position, without reading the values I've set; put the camera to my eye; and found that the meter agrees. This is what comes from using basically the same equipment (M-series Leicas) since the mid-70s. I don't need to read the details: I'm doing it by a combination of touch, and an internalized view of what's where on the dials/rings.

Cheers,

R.

Dear Roger,

first thank you for your reply, as time progresses I'm slowly overcoming the 'Oh dear, I've been doing it all wrong' feeling when reading threads like this, and your reply helps. It helps to also apply my in-bred stubborness to my photography😀

On the bold part of your answer, this very occasionally happens to me too and when it does, I always experience this envigourating mix of 'shock&awe' with a spark of pride. I greatly enjoy those rare moments when it all falls into place.

Funny thing is, when trying to guess exposure consciously I feel I'm more likely to get it wrong than when I 'fiddle everything from feeling'.

When talking to the 'metered people' about my photography, I cannot share it with them, they look at me blankly. We then both experience a mutual 'Ain't he a sad bugger' feeling for all different reasons, but there's still some kind of sharing photography present, though 😛

 

[Chriscrawfordphoto]

Hi Chris,

In general that's right if we talk about the ways things work, but it seems too precise for being true... It depends a lot on film's design as Roger said, and I'd say, also on developers: it doesn't happen the same way with Tri-X/Rodinal and TMax400/TMax developer, just to talk about two sets that behave differently, being the first one more permissive and the second one more critical...

Again, we're all saying the same in general...

Cheers,

Juan

Juan,

Yeah, the exact amount of developing time change needed for the one stop lowering of contrast varies depending on the film and developer used. I gave 25% as a starting point because it works well for most films and developers and can be fine tuned by testing if one is ambitious enough to do it.

 

[gns]

You reduce the developing time. With most films, one stop overexposure coupled with a 25% reduction in developing time will keep the dark tones at the same place they'd be with normal exposure and developing and will drop the light tones one stop lower than they'd have been with normal exposure and development.

Chris, You are now reducing the development a second time (what I meant by vicious circle). Read through the thread again from my scenario #2.
I am not getting something.

Gary

 

[Chriscrawfordphoto]

Chris, You are now reducing the development a second time (what I meant by vicious circle). Read through the thread again from my scenario #2.
I am not getting something.

Gary

No, I'm afraid you aren't. Its very simple. Reduce dev. time + increased exposure = lower contrast. If you don't understand why, it doesn't matter. Fact is, it works and is provable by simply trying it. If you're scientifically inclined, you can test it by photographing a flat even-toned surface on two rolls of film.

• On the first roll, take a reading of the surface with your meter and give 2 stops less exposure than the meter says. Then do a second photo using a reading 2 stops higher than the meter said. This roll gets developed normally.

• On the second roll set your meter's ISO speed one stop lower than what you used for the first test roll. Take a reading of the flat surface, expose two stops less than the meter says, then do another picture using a reading 3 stops over the meter. Develop for 25% less than the normal roll.

• Now look at the developed rolls. The underexposed frames represent a dark tone that is still able to hold full texture detail. They should look about the same density on both rolls. The overexposed frames represent a light tone that can hold full detail. They should be close to the same density on both rolls because of the reduced developing time, even though the light frame was given a lot more exposure on the reduced-developing roll.

 

[charjohncarter]

So, with rollfilm, make these exposure adjustments -- different EIs on the same roll. Then develop for the normal time. Not as good as shooting all at the same EI and developing appropriately, but still better than shooting all at box speed and developing normally regardless of scene contrast. Have I got the right end of the stick?

It seems I do this to a limited degree anyway, when I use my Weston Master. It has the A and C marks for contrasty and flat scenes. Auckland is one of those changeable weather places; rain, bright sun, overcast all in a few hours.

I'm glad that someone has also tried this. But like I said, I'm still not sure if it really works, at least in my erratic tries. This is just an idea (maybe crazy), and wouldn't want to lead anyone into an area without independent confirmations and also some testing which I won't do (as I'm too lazy).

 

[Roger Hicks]

Roger, Chris,

So let's take 2 scenarios.

1. I'm looking at a pretty normal contrast scene. I get my spot meter and read the darkest area where I want detail. I take my reading and stop down 2 or 3 stops (whatever) and get an exposure of 1/250th of a second. I then read the lightes area where I want detail and determine that I will use normal development time. Done.

2. Now I have a contrasty situation. I do the same...read the shadow area,blah blah blah and come up with 1/250th of a second. Now I read the light area and see that I need to contract that down by one stop, so I decide to use a short dev. I do not however go back and change my exposure to 1/125th (change iso)because I'm shortening the development, do I? It seems to me that doing that would then push my light area up one more stop requiring a further contraction. Vicious circle?

Cheers,
Gary

Dear Gary,

My own experience, from the films my wife and I use (mostly HP5 for me and Tri-X for her), is that the need to change the exposure is far more theoretical than real.

Then again, although using different paper grades gives different tonality from changing dev times, it's what the grades are for. Thus, generally, I use one of two development times: northen climes (flatter light) and southern (contrastier, so 10% less dev time, rounded down to the nearest half minute).

Also, I've been thinking quite a lot lately about tonality, etc., and I've come to the conclusion that while I may greatly admire (let us say) Chris's pictures, insofar as I can judge what they look like on my computer screen, for me content trumps technical perfection by such a wide margin that all I demand of technical quality is that it should not be so bad that I notice picture quality before image quality, or that I subsequently think 'pity it wasn't better technically'.

This is not quite as sloppy as it sounds. The less interesting the content of a picture, the higher the quality has to be, so Ansel Adams wannabees have to be a lot more technically obsessive than Cartier-Bresson wannabees. From http://www.rogerandfrances.com/subscription/ps quality 1 appropriate.html:

We hope that in the above we have made it clear that there is no such thing as absolute technical quality: there is only appropriate technical quality, and what is appropriate will vary from picture to picture. A snapshot doesn't have to be technically perfect: it's enough if it makes you smile. A 'fine art' picture may stand or fall on its technical quality; or the technical quality may be substantially irrelevant; or a technical 'fault' may have been used creatively.

Cheers,

R.

 

[Roger Hicks]

It seems I do this to a limited degree anyway, when I use my Weston Master. It has the A and C marks for contrasty and flat scenes. Auckland is one of those changeable weather places; rain, bright sun, overcast all in a few hours.

Exactly. It's not using different EIs: it's interpreting the meter reading differently, which is what A and C are for. From http://www.rogerandfrances.com/subscription/over-under-indices.html:

'A' AND 'C'

These are supplementary indices for subjects requiring less exposure than 'normal' (and ideally more development - at least 30%) and those requiring more exposure than normal (and ideally less development - we suggest about 15%). In effect, this means scenes with a limited brightness range (overcast weather) and scenes with an unusually long brightness range (sunny days with deep shadows).

The original 1956 Weston II instruction book gives as examples 'distant views and landscapes on dull days', in which case you use the 'A' (1/2) index, and 'a sunlit street with dark shadows', in which case you use the 'C' (2x) index.

The key words are 'ideally'. As noted in the post above, if you've a mixture of different scenes on the one film, you can only do one time. Like you, but apparently unlike many people on the forum, I often have a lot of different subject brightness ranges on a single roll, so I don't change dev times much, except with single sheet LF or (occasionally) with rollfilm.

Years ago, I tried both the multiple backs and multiple cameras approach, before deciding that for me the loss of immediacy was too great: deciding (or indeed remembering) which camera or back to use, having to change backs or lenses (unless I had two identical lenses on two bodies) and so forth.

With 35mm, it's MUCH quicker to bracket (best guess, best guess + 2 stops), develop normally, and to choose an appropriate paper grade.

This will brand me as hopelessly sloppy in the eyes of many, but all I can say is, hey, I have always regarded 35mm as a medium for seizing the moment. If it was good enough for Willy Ronis, it's good enough for me.

Cheers,

R.

 

[DNG]

We should God (Kodak, Fuji, Ilford, etc..), that Negative film is so forgiving, and we have wonderful developers to pick from....
When we do screw up, or have no time to make the changes in fast changing situations.

 

[Juan Valdenebro]

When I want to use a new film, what I want before being in front of real scenes with that film in my camera (and the risk of missing some good scenes) is knowing how the film behaves with different development times and kinds of light. So I routinely do a simple test that takes me just a few hours, but it's really worth it:


I buy two rolls, and do it on a sunny, cloudless day always... First I pick a scene with direct sun including whites, and shoot it at box speed incident with yellow filter doing N, N+1, N+2 and N+3, and then do the same with a second sunny scene near the first one. I advance blank frames until frame number 14 and do the same two scenes the same way. Then advance until frame 27 and do it for the last time. (The second roll is the same, but with a scene where there's no direct sun: in the shadows where light is softer and contrast lower, and the shots are N-2, N-1, N, N+1 and N+2). Shooting this takes five minutes. I find the whole-stop differences give better visual information than the sometimes too close half-stop ones...


Then I come back home and find (internet) the most common development time people (not the massive dev. chart) are using for sunny scenes, and the time they generally use for soft scenes. Then I cut the sunny film in three, load on the reel one third, and place the other two inside a black canister. I develop one with the normal time, another one with a time one third shorter, and another one with a time one third longer. Then the same with the soft light roll. Development takes three hours.


Then I go into the darkroom and make one contact print of the sunny stripes and another one of the soft stripes, both at enlarger times where the negative borders just reach pure black on paper. It takes 30 minutes.


I end up with two scenes on each kind of light, and I just pick VISUALLY the look I prefer: I write down the EI I used on my meter and the development time for the best sunny frame, and the same for the best shadows frame.


When you have in front of you both contact prints, you see the film completely. Of course any film has an unique precise sensitivity to light, but I guess the question made was not that (we all know that) but about which EI to use for metering... Reflected light metering is less precise. Metering the shadows can mean lots of things depending on the scene, and can produce really different results depending on the scene's values, and doesn't really take care of the general final range or the highlights. Incident metering with scenes on both lights including whites, gives you the chance to always expose and develop for optimal contrast right to the point where scenes' whites reach white on paper. As with slide film.


I don't use the zone system, although on my years of student I had to do it a lot to produce on negative and on paper precise gray values given by my teachers on tough exams and with negative densitometry... But as I don't place gray values or “create” images anymore, but just reflect reality, I prefer it this way.


For example I meter Tri-X incident with yellow filter on direct sun at ISO50. That's 1/250 f/8.5. But not all films are the same: with Acros I don't meter it at +3 like Tri-X, but at +2 (ISO25), and that's 1/125 f/8.5... That's a decision I took visually, preferring a frame's look to the same scene seen in three different contrast level bracketings wet printed from strips done at three different development times.


When I need a soft scene printed with normal contrast, I use a different EI on my meter than that for sun. And for really dull scenes, another one to increase contrast. I have a plastified card on my wallet and another one on each bag, and I've been completing them, updating them from my notes for the last ten years, so for all films I use I have data on the EIs and development times to use for sun, soft and pushed scenes.


It has taken a bit of time, but it's pretty easy indeed, and there's no better way IMO.


Cheers,


Juan