‘You should overexposed colour negative film’... should I??

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Tom
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#1
I’ve heard that you should overexposed colour negative film, especially the likes of Portra 400. What does this mean in real life? I shoot with a Pentax ME Super, which is auto-exposure. So if I’m using Portra 400 should I set my camera to ISO200? This is the only way I can think to do it. If this is the case, why don’t they rate it as ISO 200 and make everyone’s life easier! Any tangential advice on shooting colour negative film welcome.

Cheers,
Tom
 
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#2
I’ve heard that you should overexposed colour negative film, especially the likes of Portra 400. What does this mean in real life? I shoot with a Pentax ME Super, which is auto-exposure. So if I’m using Portra 400 should I set my camera to ISO200? This is the only way I can think to do it. If this is the case, why don’t they rate it as ISO 200 and make everyone’s life easier! Any tangential advice on shooting colour negative film welcome.

Cheers,
Tom
Yes, setting the camera to 200asa would cause it to overexpose by one stop.

Some people like the way certain films look when overexposed, and many colour films can be overexposed by a few stops and still return useable and pleasing results, Portra especially, but there’s no reason why you shouldn’t shoot it at the recommended speed.

Most film doesn’t tend to handle under-exposure as well though, so erring towards overexposure is the better thing to do if unsure.
 
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#3
Well, this is a thread that might run and run and lead to some mighty disagreements .... here's my view.

It is a truth universally acknowledged, as Jane Austen almost said, that Portra 400 will deliver good results even if it's overexposed.

There are a few web sites that give comparisons of the same scene shot with varying levels of overexposure and underexposure. This example - https://carmencitafilmlab.com/how-exposure-affects-film/ also contains a comparison with Fuji Pro 400H.

But that's not the same as saying that it SHOULD or even MUST be overexposed. Portra 400 will provide excellent results if rated at 400 - whereas there are some films (the examples I can think of are all B&W films) that don't give good shadow detail if exposed at box speed and really do need to be given extra exposure.

The amount of available light and the type of results you want to obtain may influence whether you choose to over-expose.

You could try and bracket (eg take versions at ISO400, ISO200, and ISO100), on some of your favourite scenes and see which result you like best. But if you need to shoot at 400 because there's not enough light to go lower, Portra 400 won't complain.
 
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ChrisR

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#4
I went through a phase a few years ago of adding 2/3 of a stop (so would shoot Porta 400 at 250 for example). I did think it gave richer colours than box speed Portra. But these days I more often shoot at box speed; the extra speed can be useful in keeping shutter speeds up. Just had a thought though, we've got a week in Slovenia fairly soon, and assuming plenty of light there, maybe shooting my Portra at 200 would work well!
 
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#5
So just a quick question for you guys shooting Portra at different speeds, are you also push/pull developing or leaving it as if it was shot at 400?
 

sirch

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#6
So just a quick question for you guys shooting Portra at different speeds, are you also push/pull developing or leaving it as if it was shot at 400?
Can you push/pull C41? genuine question I've never looked into it

Re the OP, to some extent it depends what you meter for. Generally with something like Portra I meter for the shadows, which may or may not be the same as over exposing either the whole scene or the highlights
 
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#9
So I’ve been reading about pushing and pulling this week and read along the lines of shooting the same speed for the entire film then adjusting the development time etc, but the guy in those 2 videos is shooting 10 different exposures on the same roll but getting “usable” results in contradiction this this. Is the fact that they’re coming out okay down to the scanner?
 
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#10
Generally with something like Portra I meter for the shadows, which may or may not be the same as over exposing either the whole scene or the highlights
I find that the phrase "meter for the shadows" is potentially confusing because there are at least two ways that phrase could be used.

a) Take a meter reading for the darkest area of the scene in which you want detail to appear. Your meter will be attempting to convert the thing you point it at to a midtone/18% grey, so opening up two stops from the meter reading will result in that shadow area being portrayed as (very imprecise term follows) dark but not black, with some detail. In Zone System terms, call it Zone 3

b) If you point your meter at the shadows and use the suggested meter reading without modification, then you are in effect overexposing.

Method (a) is, as I understand it, what someone who follows the zone system or has been loosely influenced by the zone system, means by metering for the shadows.

Method (b) will produce a brighter result, which is fine if that's what the photographer intended.

However if a photographer writes "meter for the shadows" and they mean (a) it is possible that a reader will follow method (b) and might not get the results they want.
 
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#11
So I’ve been reading about pushing and pulling this week and read along the lines of shooting the same speed for the entire film then adjusting the development time etc, but the guy in those 2 videos is shooting 10 different exposures on the same roll but getting “usable” results in contradiction this this. Is the fact that they’re coming out okay down to the scanner?
I've just re-watched the Kyle McDougall videos and, since all the shots on a roll of 120 have to be developed for the same time, it's clear that his lab has not applied any adjustment to the standard development time. My understanding is that changing the development time for C41 is not in line with the standardised method, but some people do carry out such adjustments.

A scanner, when an auto exposure adjustment is applied, will attempt to equalise the exposure from over or under-exposed negatives, but it will produce better results wth some films than others. If you're doing your own scanning, you could force the scanner software not to do automatic exposure adjustment, but I guess a commercial lab will always leave autoexposure on so that it gets the best results for most customers.
 
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#12
I've just re-watched the Kyle McDougall videos and, since all the shots on a roll of 120 have to be developed for the same time, it's clear that his lab has not applied any adjustment to the standard development time. My understanding is that changing the development time for C41 is not in line with the standardised method, but some people do carry out such adjustments.

A scanner, when an auto exposure adjustment is applied, will attempt to equalise the exposure from over or under-exposed negatives, but it will produce better results wth some films than others. If you're doing your own scanning, you could force the scanner software not to do automatic exposure adjustment, but I guess a commercial lab will always leave autoexposure on so that it gets the best results for most customers.
Perfect, the contradiction was baffling me! Sorry, thread hijack over :LOL:
 

sirch

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#13
I find that the phrase "meter for the shadows" is potentially confusing because there are at least two ways that phrase could be used.
Fair point and I guess a) is what I personally go for, assuming I am getting serious and spot metering.

(BTW I did caveat "may or may not be over exposing")
 
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#14
I sense some opportunities for confusion above.

A neg is just one stage in a sequential process. The exposure / processing of the neg isn't the final result. Its task is to record the maximum amount of detail in all tonal areas as an intermediary.

What you do with it next (scanning, printing) is another matter.

With positive ('slide') film, we need to expose with a bias to protecting the highlights. With neg film, the tones are reversed so that it's much harder to blow the highlights (dark areas in the neg). So we look to the shadows instead, to preserve detail there, and bias exposure in that direction.

Thus with a hand-held meter, or a manual in-camera averaging / centre-weighted one, for neg film you might point it (within reason) to the shadows to set the exposure. With an auto camera, you might approximate that effect by lowering the film speed setting on the camera body when you load the film. Portra 400? Set the dial to 320. Process normally. There's a certain latitude, so relax about it.

This doesn't cover all the bases, just the general feel of it.
 

excalibur2

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#15
Just a small point to add re "exposing for the shadows"......well it depends on what is important in a shot. and no need to be a slave to exposing for the shadows, and in say portraiture you would want back ground shadows (esp if something distracting was in them) reduced not enhanced for the subject to stand out, well of course unless shadows (or something in them) are related to your shot.
I'm sure we could all think of shots we have taken and didn't care what was in the shadows and it wouldn't improve your shot anyway, so why expose for them.
 
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#16
So just a quick question for you guys shooting Portra at different speeds, are you also push/pull developing or leaving it as if it was shot at 400?
Can you push/pull C41? genuine question I've never looked into it
My approach for the last few years with Portra 400, a film I have shot more than anything else (and currently have 16 rolls away for development) is to expose for the shadows, metered at 200, develop as normal. I have a good relationship with my lab and they have developed and scanned hundreds of rolls of mine over the years and their feedback on exposure is almost always good. The only difference is generally when I know I have made an error in either metering or exposure.

I have also shot at box speed and then done a one stop push, again with good results.

There are films that I don't use this approach for such as Ektar 100 which I meter for and shoot at box speed. These are some of the reasons I feel it is important to stick with the same lab and build a relationship as well as sticking with a few good film stocks that you learn to understand how they will react to different situations. Although I do have a roll of Cinestill 800, I stock I haven't shot at night time before, away for development which is going to be subject to a 2 stop push. Don't expect any results from that! Ha.
 
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#17
I don't use colour, but a common approach to black and white negative film is to expose it at half its rated ISO setting then reduce development time by about 20% This gives more shadow detail.


Steve.
 
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Tom Pinchenzo
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#18
Some good insight here so thank you. I asked the question as I’ve just fired off a roll of Portra 400 at box speed, then read about overexposure etc. I’m sending it to FilmDev for development when I get back. I’ll post some results here.
 
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#19
I wouldn't bother over exposing Portra unless you're trying for a specific effect. The latitude is good enough that you don't have to worry too much about loosing shadow detail in high contrast scenes.

Consumer C41 however like Fuji C200/Superia, Kodak Colorplus/Gold/Ultramax etc I'll always over expose a bit as the latitude for under exposure isn't as good as Portra. Typically shadows go muddy if under exposed.
 
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#20
Do you get the same results for over exposing in camera as you would by developing for extra time in the chemicals ( equal extra stops equivalent) or does this have a different affect on the look of the film ?
 
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#21
Do you get the same results for over exposing in camera as you would by developing for extra time in the chemicals ( equal extra stops equivalent) or does this have a different affect on the look of the film ?
Not quite.
I typed out a long reply that just ended up sounding like garbage, so I suggest you watch this fantastic chap explain things far far better than I ever could.

View: https://youtu.be/OdpfRqDDZyw
 
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#24

RaglanSurf

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#25
So I got my roll of Portra 400 developed and pretty happy with the results - shot at box speed and while a few were underexposed do to backlighting, I still like the tone in the shadows - kinda retro feel to it....

France 2019
by Tom Pinches, on Flickr

France 2019
by Tom Pinches, on Flickr

France 2019
by Tom Pinches, on Flickr
They’ve turned out very nicely indeed, I love the look and feel of Portra it’s pretty much the only colour negative film i use. The 800 is also fantastic, it’s a little more expensive but worth it for the more muted lighting conditions.
 
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#26
I find that the phrase "meter for the shadows" is potentially confusing because there are at least two ways that phrase could be used.

a) Take a meter reading for the darkest area of the scene in which you want detail to appear. Your meter will be attempting to convert the thing you point it at to a midtone/18% grey, so opening up two stops from the meter reading will result in that shadow area being portrayed as (very imprecise term follows) dark but not black, with some detail. In Zone System terms, call it Zone 3

b) If you point your meter at the shadows and use the suggested meter reading without modification, then you are in effect overexposing.

Method (a) is, as I understand it, what someone who follows the zone system or has been loosely influenced by the zone system, means by metering for the shadows.

Method (b) will produce a brighter result, which is fine if that's what the photographer intended.

However if a photographer writes "meter for the shadows" and they mean (a) it is possible that a reader will follow method (b) and might not get the results they want.
The phrase as expressed in the 40's and 50's was.... EXPOSE for the shadows and develop for the highlight. this results in an easily printable negative. Neither too dense nor too contrasty. this was entirely practical when using plates and cut film.
Roll film and 35mm introduced the need for exposing an entire film at one film speed and developing it all to the same gamma. this no longer allowed for individual subject treatment. it broke the link between exposure and development

How you rate a film is an entirely different matter. It has a lot to do with the type of developer you use and the time, temperature, and agitation you give it.
Firms like Kodak and Ilford Published development details with recommended time and dilutions and developers for all their films, the Gamma selected was also predicated on the type of enlarger used , cold cathode or condenser, and later enlargers with mixing chambers to diffuse the light. the aim was to be able to print a negative on Grade 2 bromide paper.

However It seems today that many people develop films to a far greater density/ contrast than previously, when it was said that you should be able to read a news paper through the highlights of a negative.
 
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#27
However It seems today that many people develop films to a far greater density/ contrast than previously, when it was said that you should be able to read a news paper through the highlights of a negative.
I get told that my film photography - especially B&W - is very 70s, which apparently means low contrast. I like tones and details regardless of whether they are fashionable or not.
 
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#28
decreased development gives...( by what ever means)
lower contrast ( lower gamma)
less density
less granularity
less apparent fill speed.
Increased development gives...
Higher Contrast
greater density
greater Granularity
Higher apparent film speed

Development can be controlled by time, temperature, dilution and by choice of developer.
Lower dilutions usually result in greater sharpness and less granularity, other things being equal.

D76 and ID11 are considered the gold standard from which other developers are measured.
Diluted 1to1 D76 or ID11 are probably the all time Gold Gold standard for roll and 35mm films, giving the best tonality and all round qualities for large prints.
Further dilution increases actuance especially when processed with less agitation (stand development). It also tends to increase shadow detail compared to highlight density.

Other Developers are usually less well balanced, but can enhance one parameter or another with some film types. but almost always by the addition of other downsides.

Actuance is the edge effect produced at the boundary between dark and light areas when an unexhausted developer from a shadow region migrates slightly to the neighbouring highlight region that has exhausted its developer. It looks similar to the effect of using an unsharp mask in Photoshop. It only works with dilute developer and low agitation.

Low agitation with dilute developers also has has a different affect ... in this case development continues in the shadow regions when the development is complete in the highlight regions. It necessitate careful exposure so as not to over expose the highlights, or they will become uniformly dense, with out usable detail. (this was called compensating development.) Tetenhall Neofin blue was the most successful High actuance compensating developer. It was a one shot developer of extreme dilution, and best used with slow thin film emulsions Like Adox R14 or 17. (I produced sharp full tone, three meter wide prints in the 1950's from Rollei negatives using this film and developer.)
 
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#29
I get told that my film photography - especially B&W - is very 70s, which apparently means low contrast. I like tones and details regardless of whether they are fashionable or not.
I would prefer to call it normal contrast when a print goes from a full black to a full white but with details in both the shadows and highlights. this goes for both High and low key images. in either case tones should be smooth and defined, with out any muddiness.
The so called soot and whitewash was never well received. nor was grey and muddy.
 
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