Film: ETTR with Film in Low light: What Films and Processing for usable pictures?

[Asher Kelman]

Maris points out, in a current thread on ETTR in digital cameras, here, the long tradition film photographers have had in getting the important subjects well over to the right in exposure. So it's apt to devote a new thread just to the processes for achieving this with our film cameras to get usable images we can make into impressive prints.

Originally Posted by Maris Rusis

I agree ETTR is a powerful exposure strategy. Some film photographers have been doing it for decades. The late Fred Picker put it succinctly when he suggested "place your high value on Zone VIII, shoot, and accept what you get in the shadows".

In a general philosophical sense the best recording of an image, film or digital, is the one that contains the maximum possible information. This is equivalent to the maximum usable exposure. No, not the maximum achievable exposure but rather the maximum beyond which you lose information; notionally Zone VIII in film or level 255 in digital.

So Maris, Jim Galli, Ben Rubinstein, Mike Shimwell, Cedric Massoulier, Nigel Allan and other film photographers,

We now have, a still small but expanding, nucleus of OPF photographers returning, at least partly, to real film. This really makes me feel that we are indeed starting to take advantage, once again, of the broadest possibilities for working with light and the foundations of the art. You, I know have such a lot of experience with fine imaging. So I'm going to ask you to help move us along the path of ETTR, taking advantage of all you know about film, where processing is so fundamental to the curve by which the light is written into the paper with silver deposits.

If you could add "pushing development of film with a particular developer", which color and black and white films would you choose, with what development times for the highest value subjects in zone VII? IOW, how low EV could you still get a usable exposure for film?

Asher

[Mike Shimwell]

Asher,

Tired and getting ready for work now, but I'll give this some thought.

Mike

[Bart_van_der_Wolf]

Originally Posted by Asher Kelman

Maris points out, in a current thread on ETTR in digital cameras, here, the long tradition film photographers have had in getting the important subjects well over to the right in exposure.

Hi Asher,

I disagree with that observation, in particular for negative film.

The development of negative film is focused at getting a combination of exposure and development that results in 'adequate' shadow density in film. Adequate is usually quantified at 0.10 optical density above fog and base density. The rest of the tonescale can be somewhat adjusted between that point on the characteristic curve and D-max, wherever it may fall (there is no clear Right/D-max to expose for). Also the granularity and acutance can be influenced by the type of developing agent(s), dillution, and agitation. Temperature is usually only used to influence the time needed, but there can also be an effect on the activity of the specific agents in the developer's chemical mix. The characteristic curve of most negative films is engineered to suit a certain paper's characteristic curve, effectively trying to linearize the combined film+paper curves response and define overall contrast.

Slide film, on the other hand, does benefit from ETTR. It has a somewhat gentler roll off in the highlights (D-min) than linear response digital sensors. The color accuracy of the deepest shadows (certainly the last 1/3rd stop) is generally poor due to a different D-max per color layer, so anything that can be lifted above that level will be easier to scan, and has better color. Overexposure does lead to clipping, just like with digital sensors, but is less abrupt (and thus has lower highlight contrast). Traditionally slide film was engineered to also compensate for losses in projection, but more recent slide/reversal film was also better suited for scanning. Scanning slide film requires a scanner capable of dealing with the high D-max.

In principle, the only difference in tonality between digital and film is in tonemapping. Since digital, at modest ISOs, has a larger dynamic range than slide film, it is possible to effectively mimic the slide film look by proper tonemapping. There are of course other characteristics that do differ between film and digital, but those are more subtle (and can also be mimiced by digital, including e.g. graininess). Scanning negative film is less challenging due to the lower D-max, but since the resulting scan contrast needs to be boosted for output, noise/graininess needs special care. In color negatives, special care needs to be given to proper 'removal' of the masking layer by tuning the exposure times of the individual R/G/B sensors for the D-min (film support+mask), otherwise color accuracy and graininess will suffer.

Cheers,
Bart

[Michael Fontana]

Originally Posted by Bart_van_der_Wolf

Hi Asher,

I disagree with that observation, in particular for negative film.

The development of negative film is focused at getting a combination of exposure and development that results in 'adequate' shadow density in film. Adequate is usually quantified at 0.10 optical density above fog and base density. The rest of the tonescale can be somewhat adjusted between that point on the characteristic curve and D-max, wherever it may fall (there is no clear Right/D-max to expose for). Also the granularity and acutance can be influenced by the type of developing agent(s), dillution, and agitation. Temperature is usually only used to influence the time needed, but there can also be an effect on the activity of the specific agents in the developer's chemical mix. The characteristic curve of most negative films is engineered to suit a certain paper's characteristic curve, effectively trying to linearize the combined film+paper curves response and define overall contrast.

Slide film, on the other hand, does benefit from ETTR. It has a somewhat gentler roll off in the highlights (D-min) than linear response digital sensors. The color accuracy of the deepest shadows (certainly the last 1/3rd stop) is generally poor due to a different D-max per color layer, so anything that can be lifted above that level will be easier to scan, and has better color. Overexposure does lead to clipping, just like with digital sensors, but is less abrupt (and thus has lower highlight contrast). Traditionally slide film was engineered to also compensate for losses in projection, but more recent slide/reversal film was also better suited for scanning. Scanning slide film requires a scanner capable of dealing with the high D-max.

In principle, the only difference in tonality between digital and film is in tonemapping. Since digital, at modest ISOs, has a larger dynamic range than slide film, it is possible to effectively mimic the slide film look by proper tonemapping. There are of course other characteristics that do differ between film and digital, but those are more subtle (and can also be mimiced by digital, including e.g. graininess). Scanning negative film is less challenging due to the lower D-max, but since the resulting scan contrast needs to be boosted for output, noise/graininess needs special care. In color negatives, special care needs to be given to proper 'removal' of the masking layer by tuning the exposure times of the individual R/G/B sensors for the D-min (film support+mask), otherwise color accuracy and graininess will suffer.

Cheers,
Bart

I agree, Bart. Pulling Negs is a nono!

In practical terms, for outdoor shots, especially with single-sheetet 4/5'-slides I used to run the following ETTR-scenario, with bracket shooting to reduce high contrast:

- 2 exposures were taken at the technically best exposures, offsett 0
- 1 with + 1/2, and
- 1 with - 1/2.

This proviedes a additional range of 1 f-stop for capture plus 1/2 - 3/4 f-stops for developement.
Often the best scenario was the ETTR:

First, one of the offsett 0-films went to the Lab, based on that, the corrections followd.
Over all a exposures + 1/2 and a shorter developement ( = pull 1/2) showed the nicest tones, just at the border of getting colorshifts, therefore sometimes pull 1/3 was better - one had to guess...

The - 1/2 was just for "backing up" blown highlights, but remained mostly undeveloped.

I'm not sure if the labs are still developing pull-push - anyway going 4 x to the lab and back is here not a realistic scenario anymore, due to the long times, out of 4 labs some years ago, we have one left, at the other end of town.

[Bart_van_der_Wolf]

Originally Posted by Michael Fontana

I agree, Bart. Pulling Negs is a nono!

The only adjustment I used was with Portra 160, which I exposed at ISO 125 for better shadow density and graininess, but I didn't pull that either. In fact, I ran a test with several Pro labs, and was amazed how much their results varied (and their average QC was better than in most other countries).

Black and White negatives offer more developer control than a color process.

In practical terms, for outdoor shots, especially with single-sheetet 4/5'-slides I used to run the following ETTR-scenario, with bracket shooting to reduce high contrast:

- 2 exposures were taken at the technically best exposures, offsett 0
- 1 with + 1/2, and
- 1 with - 1/2.

This proviedes a additional range of 1 f-stop for capture plus 1/2 - 3/4 f-stops for developement.
Often the best scenario was the ETTR:

First, one of the offsett 0-films went to the Lab, based on that, the corrections followd.
Over all a exposures + 1/2 and a shorter developement ( = pull 1/2) showed the nicest tones, just at the border of getting colorshifts, therefore sometimes pull 1/3 was better - one had to guess...

The - 1/2 was just for "backing up" blown highlights, but remained mostly undeveloped.

Yes, that's a sound workflow for reversal/slide film. One needs to rely on the QC in the Lab to be within margins though, and some are better than others (or should I say some are even worse than others?).

I'm not sure if the labs are still developing pull-push - anyway going 4 x to the lab and back is here not a realistic scenario anymore, due to the long times, out of 4 labs some years ago, we have one left, at the other end of town.

Indeed, Their numbers are going down, and quality may suffer as a concequence when the good Lab technicians retire. The good ones still push and pull, but they are also transitioning to digital postproduction, so the volumes go down as well (which is also not good for the processing quality).

Cheers,
Bart

[Maris Rusis]

Maybe it is too glib to merely say the maximum usable film exposure, Expose To The Right, is the best exposure without being more explicit about what usable means.

Small format film, say 35mm, runs into problems at densities much below what large format film can accommodate. Grain in the positive image is a map of the spaces between the grains of the negative. 35mm film offers fewer and fewer "spaces" to the enlarger lens at optical densities much above 1.0 and increasing graininess tends to dominate detail, acutance, and tonal smoothness. If low graininess is the key criterion for exposure "usability" then the minimum exposure that records desired picture elements is often the maximum as well. This implies exposure precision is critical with miniature film. But fast moving 35mm work rarely allows time to fuss over the subject matter with a spot meter. What to do? Put the high value on Zone VIII and shoot. It's ETTR again!

Large format film is much more forgiving of heavy exposure. That's how the ancient photographers got by in the days before light meters- if in doubt give it more. I can confirm from experience that 8x10 black and white film continues to deliver tone, gradation, and sharpness with the high values placed on Zone XV; that's 7 stops "overexposure". Even more exciting, in theory at least, is the fact that the negative holds 15 stops worth of photometric information. High Dynamic Range indeed! But is it "usable"? Not really.

A seriously thick negative (looks like a solar eclipse filter) takes a long time to expose over photographic paper. Trust me, making 15 minute exposures in the darkroom just to get a picture is one of the least creative ways to waste an afternoon. And of course the sky will need a couple of stops worth of burning in. Good luck with all that. If productivity is "usability" then bullet proof negatives are not the way to go.

An important and sometimes overlooked limit on how far to ETTR is subject matter itself. Pretty well all over the world bright sunny days are the same and reflective subjects offer a familiar line-up of tones. These range from things that look black in the shade to white things in sunlight. The conceptual distance from "looks black" to "looks white" is only about eight stops . Just about any negative film can easily swallow this.

There is no point in having 15 stop film or exposing 7 stops to the right. Sure, there are artificial 15 stop subjects, windows into unlit rooms next to sun-discs for example, but by the time they are laid down on photographic paper they resemble 8 stop subjects. In a photograph of a full range scene if the darkest thing looks black and the brightest thing looks white the mind will accept it and the eye will never recoil. Rendering subject brightnesses as photographic tones is a fiction but a plausible and beguiling one.

So, even with big film one can ETTR but going beyond about Zone IX or maybe Zone X brings only difficulty and no reward.

[Asher Kelman]

Originally Posted by Maris Rusis

So, even with big film one can ETTR but going beyond about Zone IX or maybe Zone X brings only difficulty and no reward.

Let me suggest Maris, just where I'm seeking reward. In photographing a large orchestra, or just a quartet, the players are lit from above. The tops of the head are bright. The eye sockets shadowed.

If one exposed for the face, the hands and top of the head vanish! So for digital work, at Bart's suggestion, (thanks for the Dutch again), I first take take the well exposed pictures at a high ISO, say 3200 or 6400. I then use one or two ISO steps below what works at -1 to 1.5 EV. That way we can limit noise a little and recover the highlights in RAW processing. It works fairly well. Here are pictures taken at high ISO with the Canon 5DII DSLR and with some modest negative exposure compensation here. That's the best I can say!

Now, from what you are saying about LF film, I might be able to underexpose film with my LF 8x10 camera, just a few stops and then use a longer exposure light for making the prints or the equivalent in scanning the film.

Any ideas on this way of working? Will it enable me to avoid getting the foreheads and hands blown out and get all the detail I want in the faces? What film and processing would you suggest?

Thanks,

Asher

[Mike Shimwell]

Originally Posted by Asher Kelman

Let me suggest Maris, just where I'm seeking reward. In photographing a large orchestra, or just a quartet, the players are lit from above. The tops of the head are bright. The eye sockets shadowed.

If one exposed for the face, the hands and top of the head vanish! So for digital work, at Bart's suggestion, (thanks for the Dutch again), I first take take the well exposed pictures at a high ISO, say 3200 or 6400. I then use one or two ISO steps below what works at -1 to 1.5 EV. That way we can limit noise a little and recover the highlights in RAW processing. It works fairly well. Here are pictures taken at high ISO with the Canon 5DII DSLR and with some modest negative exposure compensation here. That's the best I can say!

Now, from what you are saying about LF film, I might be able to underexpose film with my LF 8x10 camera, just a few stops and then use a longer exposure light for making the prints or the equivalent in scanning the film.

Any ideas on this way of working? Will it enable me to avoid getting the foreheads and hands blown out and get all the detail I want in the faces? What film and processing would you suggest?

Thanks,

Asher

Hi Asher

If you underexpose negative film you will have a clear sheet. Even if there is any detail, you will need short exposures to print it on paper. Most neg film in my experience is far less tolerant of under compared to overexposure, which is why pushed film often looks like black and white rather than shades of grey. In 35mm the penalty for over exposure, apart from difficult scanning/printing, tends to be increased grain before you burn the highlights.

Mike

[Asher Kelman]

Originally Posted by Mike Shimwell

Hi Asher

If you underexpose negative film you will have a clear sheet. Even if there is any detail, you will need short exposures to print it on paper. Most neg film in my experience is far less tolerant of under compared to overexposure, which is why pushed film often looks like black and white rather than shades of grey. In 35mm the penalty for over exposure, apart from difficult scanning/printing, tends to be increased grain before you burn the highlights.

Mike

Mike,

How about prolonged sitting in dilute developer for under-exposed film or would the highlights clip again?

Asher

[Mike Shimwell]

Originally Posted by Asher Kelman

Mike,

How about prolonged sitting in dilute developer for under-exposed film or would the highlights clip again?

Asher

Hi Asher

Here is 'The Thread' on this topic. P Lynne Miller has some apparently excellent results from TriX in dilute Rodinal. I've not pushed as far as he has, but you might get something useable (best to practice before it's important). I don't like HP5 in Rodinal (use Xtol), but TriX is excellent.

Mike

[Maris Rusis]

Originally Posted by Asher Kelman

Now, from what you are saying about LF film, I might be able to underexpose film with my LF 8x10 camera, just a few stops and then use a longer exposure light for making the prints or the equivalent in scanning the film.

Any ideas on this way of working? Will it enable me to avoid getting the foreheads and hands blown out and get all the detail I want in the faces? What film and processing would you suggest? Asher

Short of photographing direct light sources or specular reflections most large format negative film does not "blow". With sufficient exposure and conventional processing it just builds density and records detail. Getting the information back from very dense parts of a 8x10 negative can be tedious but it's all there.

The opposite challenge comes from subject matter that is contrived to include lit and unlit portions. An orchestra on stage, top lit for audience visibility but with no light on the musicians faces to minimise their eye-glare for reading sheet music, would be a good example. A wide enough lighting ratio, perhaps like Asher's example, can't be captured by anything including large format negative film.

It may be a provocative suggestion but I believe it true that lighting ratios which defeat large format film also defeat the human eye. Beyond a 8 or 9 stop limit it is not possible to see detail on a brightly lit forehead and a shadowed face simultaneously. And yet experience seems to confirm that this is in fact easy. What is going on? High Dynamic Range is what is happening.

The detailed filled picture of the bright forehead and the shadowed face exists only in the mind. It is an involuntary brain construct fabricated out of multiple "looks" at various parts of the subject matter. We "see" things in HDR and we can't turn it off!

A further provocative suggestion may be that no one knew what the world looked like without HDR until photography was invented. In that sense photography may afford a more accurate picture of the world than mere looking. One could even surmise that photography is peculiarly well adapted for making "pictures from the world" while digital image processing affords the possibility of making pictures that mimic those "from the mind".

[Asher Kelman]

Maris,

Yes, musicians squinting trying to read sheet music with light from the front, is best avoided. what's the equivalent with film of under-exposing b y say 1.5 EV and then recovering highlights in processing?

Is there anything to gain using a 4x5 or 8x10 camera and what film, color and B&W would you suggest?

Asher

[Nigel Allan]

Originally Posted by Mike Shimwell

Hi Asher

If you underexpose negative film you will have a clear sheet. Even if there is any detail, you will need short exposures to print it on paper. Most neg film in my experience is far less tolerant of under compared to overexposure, which is why pushed film often looks like black and white rather than shades of grey. In 35mm the penalty for over exposure, apart from difficult scanning/printing, tends to be increased grain before you burn the highlights.

Mike

I have done very little darkroom work and always paid labs to do it for me whenever I ned a nice print or cibachrome. I have developed a little black and white but wouldn't have a clue about E6 processing, so most of what you are discussing is over my head technically but I will say that in my experience I routinely overexposed black and white film by one stop as underexposed black and white film/prints are horrible, and I routinely underexposed colour tranny by one to two thirds to give greater depth and richness of colours as overexposed trannies are equally horrible IMHO with weak washed out colours.

I always felt 'safe' over exposing HP5 or TriX and underexposing Ektachrome as both strategies gave me strong usable tones in my finished product

With my limited knowledge of digital sensors (I've had a dSLR precisely 5 months) I was told originally that they are better treated the same as if you were shooting with trannies so as 'not to blow the highlights' as it is easier to recover darker areas than 'blown' areas, but I am beginning to question that received wisdom and feel you can expose to the right slightly but not too much to 'suck in' more data into the sensor from the scene

That's about as technical as my conversation can get on this subject :)...and probably doesn't contribute much at all to the discussion, but thats my experience and my two pennies

[Mike Shimwell]

Originally Posted by Nigel Allan

I have done very little darkroom work and always paid labs to do it for me whenever I ned a nice print or cibachrome. I have developed a little black and white but wouldn't have a clue about E6 processing, so most of what you are discussing is over my head technically but I will say that in my experience I routinely overexposed black and white film by one stop as underexposed black and white film/prints are horrible, and I routinely underexposed colour tranny by one to two thirds to give greater depth and richness of colours as overexposed trannies are equally horrible IMHO with weak washed out colours.

I always felt 'safe' over exposing HP5 or TriX and underexposing Ektachrome as both strategies gave me strong usable tones in my finished product

With my limited knowledge of digital sensors (I've had a dSLR precisely 5 months) I was told originally that they are better treated the same as if you were shooting with trannies so as 'not to blow the highlights' as it is easier to recover darker areas than 'blown' areas, but I am beginning to question that received wisdom and feel you can expose to the right slightly but not too much to 'suck in' more data into the sensor from the scene

That's about as technical as my conversation can get on this subject :)...and probably doesn't contribute much at all to the discussion, but thats my experience and my two pennies

Hi Nigel,

expose to the right is the standard mantra for digital, but what it is saying really is that digital sensors are linear up to the point they are full - i.e. they blow highlights in a hard manner. ETTR as astrategy aims to push the brightest areas of the subject where you want to retain detail to the highest values that are not blown and so obtain more information and less noise in the shadows. There are some caveats, but broadly it works if you know what highlights you can afford to blow and what you can't. Also, you need to be aware that the camera lcd display is based on an embedded jpg and not the raw file, which can be very different in terms of the amount of highlight headroom.

For the sort of work you have shown so far, ettr may actually be a very difficult strategy in practice:)

Mike

[Nigel Allan]

Originally Posted by Mike Shimwell

Hi Nigel,

For the sort of work you have shown so far, ettr may actually be a very difficult strategy in practice:)

Mike

OK, now you have engaged my curiosity...neat move Mr Shimwell, can you elaborate and explain this? It might give me an insight into what I shoot and how I like to see the world :) and help me improve

[Mike Shimwell]

Originally Posted by Nigel Allan

OK, now you have engaged my curiosity...neat move Mr Shimwell, can you elaborate and explain this? It might give me an insight into what I shoot and how I like to see the world :) and help me improve

Hi Nigel

A lot of your pictures are moments, rather than set up camera on a tripod type work. If you really want to do ettr you need to control everything so that you can put the highlights on the edge of clipping. If the scene was in shadow you'd increase the exposure to maximise data and then adjust back down in post processing. If the scene was highlighted you'd make sure you clipped only the bits you wanted and again adjust after the fact. You might even expose a high brightness range scene using 3, 5 or 7 different exposures and then combine afterwards in photoshop or using a tool like TuFuse or photomatix. All of this is a very different approach than taking moments from the world around you:)

That is not to criticise either, and some people do a bit of both, but ettr can break down when you are likely to photograph different scenes in quick succession or don't have time to shoot, check, adjust, shoot again and repeat. Having said that, being aware of the technical side of photography can be useful however you work. James' Ravillious' early work is apparently much harder to print than his later as he was dismissive of the technical side initially, but later learned to expose and develop to create negs that were easily printable to give the look he wanted with minimum dodge and burn. Interestingly, he commented that when he saw an Ansel Adams print it looked as though it was made of lots of different pieces.

Mike

[Nigel Allan]

OK, I see what you mean, however I have often tended to take my exposure for the whole shot from a particular area I like the look of even when shooting 'moments' as you put it.

I would frequently use the camera's metering system to 'measure' a point or area within the frame/scene I liked the intensity or brightness of which was not necessarily the same as my focal point and then turn my camera back to my subject....so to an extent I have always done this sort of thing instinctively.

[Mike Shimwell]

Yep, there's nothing new...

MIke