Portra Color Film shooting advice needed

[Alan Klein]

When bracketing Portra +/- one stop, I noticed that there is a slight color shift even though all settings gave me acceptable exposure results. Since I shoot landscapes mainly, it probably doesn't matter. However, if you're looking to match the actual colors, exact exposure seems to be more important.

 

[timparkin]

Kodak (and Fuji and Ilford) actually measures the box speed per an industry standard, if you use your incident meter and your shutter and aperture are accurate you can get very close to shooting at the standard, which means you can print in a nearly standard manner.

That is true - but their testing methodoloy gives you no information about latitude in highlights and shadows. Transparency film typically blows out at +2 stops but can have -6 stops in the shadows (DxO test results) whereas neg has +14 in the highlights and -2 in the shadows.

Given this information, the 'correct' exposure based on box speed may blow out highlights or block up shadows depending on scene contrast. Without checking, it is therefore better to slightly underexpose transparency film and overexpose neg film. But with checking it's better to place your tones where you want them!

Tim

 

[markbarendt]

Well first of all we are talking about C41 negative films, specifically Portra, not trannies/slides, and actually the standard does have a very specific relationship to the film curve. That relationship has a "safety factor" built in at the shadow end.

All the manufacturers use the same standard. The beauty of this is that we dont have to test every film to get good results.

The wild card is "us", not the films. Each of us has different expectations and ways of working.

Using negative films, setting exposure with an incident meter at box speed, and developing them by-the-book, IMO provides the most reliable way to get high-quality, easily workable negatives, bar none.

I'm not suggesting that there aren't good reasons to shoot at something other than box speed, or for using spot meters, I'm simply saying that using non-standard settings and reference points should be reserved for "special effects" or "special situations".

 

[DREW WILEY]

If you get the results you want, that's all that matters. But my own objective is to understand color neg films well enough to get them to approximate or even surpass certain expectation I had after years of printing chromes. That takes a lot of testing. And the different Kodak film are really engineered for different markets.
Portra 160 is one thing, 400 another, and Ektar yet a different animal. It's not simply a matter of latitude or contrast. The three color layers in color neg film are not as well differentiated in chromes. Just compare the spectral sensitivity charts of negs vs chromes, or even of the respective color neg products themselves. Films
like Portra 160 are engineered to produce complex warm neutrals, namely, pleasing skintones under a wide variety of lighting circumstances. If you have a similar kind of color in the scene like a warm earthtone or orange,
it is going to fall into the same hue category. Greens still tend to be contaminated with a lot of cyan. Overexposure will overlap the dye curves even more. Not a felony unless you're trying to protect the reproduction of certain fussy non-skin hues too, which if in fact the name of the game in most landscape photography, or possibly in enviro portraiture. A different problem than say, copying a painting under controlled
studio lighting of limited contrast range, then boosting the contrast afterward for reproduction. After a lot of
futzing around (painfully, for sure, given the cost of 8X10 color film and real prints!), I'm beginning to understand
what it take to make these films work as a substitute for chrome. Of course, I'm hedging my bet by stuffing the
freezer with film just in case Kodak tanks. But I made the transition once it was apparent Cibachrome was going
under and RA4 is the future of high-quality color printing. I don't want prints that look like traditional color neg
work! I want clean, crisp differentiated hues across a wide spectrum. But in the process I've learned a few
things that will help just about anyone improve their results, if they're interested.

 

[RPC]

Unless someone goes to the trouble to test his meter, metering techniques, aperture, and shutter for accuracy, he never really knows for sure his true shooting speed. Therefore, because of the lattitude of color negative films I believe it is best to shoot at some degree of overexposure until such tests are made to prevent underexposure and loss of shadow detail if the shooting errs on that side. Half box speed (one stop over) will probably take care of most errors.

 

[DREW WILEY]

I should probably explain a little more ... Here in Calif we have exquisite summer and fall colors consisting of all kinds of subtle shades of gold, gray-green, rust hues. These are very kinds of colors color neg film has a terrible
time differentiating. Even chromes are tricky with these kinds of colors. Watercolorists have been able to do a wonderful job reproducing the special qualities of the color and atmosphere here; but film is another story. Dye
transfer printing works to a degree, but fails at capturing really intense detail on large scale. The last thing I personally want is traditional Vericolor mud and mush like Misrach or Meyorwitz or Shore mastered, or at the opposite end, the jam and honey atop sugar cube saturation that every fool with Fautoshop does. Making color
sing is really a matter of nuance, not noise. After a couple of years of making decent CA prints from Portra, but
maybe only a couple of masterpiece images comparable to what I attained in Cibachrome, I'm finally beginning to
understand some riddles, and am squeezing some difficult landscape color relationships out of these newer Kodak
films which are giving me hope. In the meantime, RA papers have improved enough to make a difference too, and
I've relearned some advanced masking technique specifically appropriate to color neg work.

 

[markbarendt]

Unless someone goes to the trouble to test his meter, metering techniques, aperture, and shutter for accuracy, he never really knows for sure his true shooting speed. Therefore, because of the lattitude of color negative films I believe it is best to shoot at some degree of overexposure until such tests are made to prevent underexposure and loss of shadow detail if the shooting errs on that side. Half box speed (one stop over) will probably take care of most errors.

Yes testing is important but here are three thoughts to consider;

One, the standard already has a safety factor. Stephen Benskin has had numerous discussions here that touch on this and books like Dunn & Wakefield's Exposure Manual and the encyclopedia of photographic processes are worth reading when we really want to know what's what there.

Two, we have no idea which way the aperture and shutter are "off" without testing. Adding exposure "just because" can actually compound the problem.

Three, a single test roll or 3 sheets should be plenty to see if you are "close enough" to normal or if an adjustment one way or another is warranted.

 

[timparkin]

I should probably explain a little more ... Here in Calif we have exquisite summer and fall colors consisting of all kinds of subtle shades of gold, gray-green, rust hues. These are very kinds of colors color neg film has a terrible
time differentiating. Even chromes are tricky with these kinds of colors. Watercolorists have been able to do a wonderful job reproducing the special qualities of the color and atmosphere here; but film is another story. Dye
transfer printing works to a degree, but fails at capturing really intense detail on large scale. The last thing I personally want is traditional Vericolor mud and mush like Misrach or Meyorwitz or Shore mastered, or at the opposite end, the jam and honey atop sugar cube saturation that every fool with Fautoshop does. Making color
sing is really a matter of nuance, not noise. After a couple of years of making decent CA prints from Portra, but
maybe only a couple of masterpiece images comparable to what I attained in Cibachrome, I'm finally beginning to
understand some riddles, and am squeezing some difficult landscape color relationships out of these newer Kodak
films which are giving me hope. In the meantime, RA papers have improved enough to make a difference too, and
I've relearned some advanced masking technique specifically appropriate to color neg work.

Out of interest, if dye transfer works, then the film must have the information on it. I presume you aren't scanning because you want a photographic reproduction (i.e. do you scan at all)? I've been playing with Portra quite a bit (160 mostly because 400 does'nt seem to have as balanced a colour response).

Tim

 

[RPC]

Yes testing is important but here are three thoughts to consider;

One, the standard already has a safety factor. Stephen Benskin has had numerous discussions here that touch on this and books like Dunn & Wakefield's Exposure Manual and the encyclopedia of photographic processes are worth reading when we really want to know what's what there.

Two, we have no idea which way the aperture and shutter are "off" without testing. Adding exposure "just because" can actually compound the problem.

Three, a single test roll or 3 sheets should be plenty to see if you are "close enough" to normal or if an adjustment one way or another is warranted.

There is no way to say for sure that any safety factor built in is going to safely cover all underexposure errors that might be a combination of metering and camera errors. If the errors are off on the side of overexposure, then adding more exposure, due to the lattitude of the film, is very unlikely to cause a problem. It would take a fair amount of testing to test various metering situations, all apertures and shutter speeds and shutter consistancy, especially if one has several lenses. Without such tests, adding a stop of exposure is simply a safer way to go. I do it and have never had a problem as a result.

 

[DREW WILEY]

Tim - dye transfer is done from chromes, not color neg film (although there is a rather complicated
way of doing it from negs; and there was once a special type of DT film for neg film use per se).
And there is an analogous method of retrieving info from color neg layer by layer and correcting the
bias in each of these by doing scanned color separations and post-correction (more a prepress
technique rather than ordinary PS). But neg film in general has a horrible time with certain color
issues in nature. Low contrast types like Portra and more difficult to correct for my personal goals
than something like Ektar. But Ektar has its own distinct idiosyncrasies. All films do. It's just that with
chromes the learning curve goes a little faster because you can just slap the thing on a lightbox and
see what is going on. And chromes haven't changed a lot in the last few decades - just incrementally. These new Kodak products are analogous to older color neg films, but really way more
versatile in terms of color gamut. But they still need advanced post-processing for certain color issues.

 

[markbarendt]

There is no way to say for sure that any safety factor built in is going to safely cover all underexposure errors that might be a combination of metering and camera errors. If the errors are off on the side of overexposure, then adding more exposure, due to the lattitude of the film, is very unlikely to cause a problem. It would take a fair amount of testing to test various metering situations, all apertures and shutter speeds and shutter consistancy, especially if one has several lenses. Without such tests, adding a stop of exposure is simply a safer way to go. I do it and have never had a problem as a result.

I used to do shoot at 1/2 box too and I'm not afraid of overexposing when there's a good reason to.

I actually liked the idea of not worrying about underexposure and I didn't trust my tools or myself enough.

What I've found over time with incident metering (as the OP is doing) is that when I make exposure setting errors, they are normally doozies, like taking a reading and completely forgetting to adjust the lens/camera; shooting at 1/2 box speed never "saved" a single shot where I screwed up like this.

The other thing that I've found with incident metering is that, when I actually do what the meter tells me, which is the norm; exposure is spot on no-ifs-ands-or-buts, I get just what I expect every time. In this "normal" case, shooting at 1/2 box speed gives me no advantage but it still costs me a full stop of shutter speed in the field.

Once I understood how accurate my tools were, and that I could do it, the idea of shooting at 1/2 box speed lost all it's appeal.

 

[Dismayed]

Sure, shoot at box speed if you're using a spot meter. Meter the shadows and drop exposure by two stops (assuming that your shutter is accurate). Otherwise add 1/3 - 1/2 stop of exposure to be certain that you capture some detail in deep shadows.

 

[DREW WILEY]

I spot meter everything. ... well, except for a couple times I dropped my meter in a creek and had
to determine exposure from memory! (It worked.) Spot meters are especially nice if you switch between color and black and white film, which is easy to do with a view camera. But the important
thing is just to get comfortable with the personality of your meter. Even when I was young and had
only an external CDS averaging meter on an early Pentax and shot Kodachrome in it, I never got a bad exposure - they were all spot on, no matter where I went.

 

[benjiboy]

I used to do shoot at 1/2 box too and I'm not afraid of overexposing when there's a good reason to.

I actually liked the idea of not worrying about underexposure and I didn't trust my tools or myself enough.

What I've found over time with incident metering (as the OP is doing) is that when I make exposure setting errors, they are normally doozies, like taking a reading and completely forgetting to adjust the lens/camera; shooting at 1/2 box speed never "saved" a single shot where I screwed up like this.

The other thing that I've found with incident metering is that, when I actually do what the meter tells me, which is the norm; exposure is spot on no-ifs-ands-or-buts, I get just what I expect every time. In this "normal" case, shooting at 1/2 box speed gives me no advantage but it still costs me a full stop of shutter speed in the field.

Once I understood how accurate my tools were, and that I could do it, the idea of shooting at 1/2 box speed lost all it's appeal.

I agree with you entirely Mark, I've been using incidental metering for more than forty years and have found that for 95% of subjects with any negative or transparancy film rated at the boxed speed it produces uncannily accurate results with a single reading pointing the meter from the subject to the camera without having to do any mental arithmetic, or in difficult lighting situations The Duplex Method taking two readings, one with the dome pointing at the main light source, and another from the subject to the camera and using the mean average of the two readings as the exposure to set. I'm surprised that more photographers don't use incidental light metering it's magic.

 

[markbarendt]

I'm surprised that more photographers don't use incidental light metering it's magic.

Me too.

Maybe that's St. Ansel's fault.

 

[TheFlyingCamera]

The reason to use spot metering vs. incident metering is to determine the contrast range of a scene. An incident meter reading won't tell you that. Also, for various reasons it may not be possible to get your incident meter into the same lighting as your subject (you're standing on the shaded bank of a raging river, and your subject is midstream in full sun, etc). That's when folks who understand how to use various types of metering use spot over incident. The reason most people don't use incident is that they've been trained by their camera with built-in TTL metering to rely on the in-camera meter and when not using an in-camera meter, they default to the same style of reflected light metering- if it's good enough for the camera, it must be good enough for me too.

 

[Diapositivo]

A polariser is a filter which cannot be simulated during printing. You cannot "polarize" the light after film impression. So I would say, bring a polariser, in case you need it. Besides being precious if you have to take pictures from behind a window (boat), or behind a glass (aquarium), or behind a veil of water (rocks at bottom of spring, fishes etc.) it can be useful for meadows, flowers to eliminate some "mirror reflection" from the grass blades and have more saturated colours.

As far as the exposure index is concerned, my advice for colour negative film is: always box speed, but do meter for the shadows.

That is:
- Scene entirely lit by sun: expose at box speed;
- Scene entirely in the shade: expose at box speed;
- High contrast scene, with part of the subject in sunlight, and part in shade: expose as if the subject were entirely in shade.

In this third case, if you don't want to think too much about it, assuming it's not a backlit scene, just open 1.5 stops more than the camera suggested exposure. The exposure difference between the two regions is probably around 3 EV and your internal light meter will probably give you a roughly average exposure, so by opening 1.5 stops you will be exposing for the shadows.

 

[DesertNate]

While F1.4 didn't exactly explain what he was saying, I can confirm that shots I have deliberately overexposed on Portra 160 have better shadow detail (obviously) without serious detrimental effects to the highlights. I am inclined to agree that for the purpose of landscape and general photography, Portra benefits from a stop of overexposure. It's pretty low-contrast stuff, and while the differences at the highlight portion of the scene are barely noticeable, the differences in the shadows are very noticeable, and overexposure gives quite a bit of freedom in post.
I prefer slide film for landscapes, but for travel, I use negative film because I don't know what I'm going to be wanting to shoot.

 

[markbarendt]

The reason to use spot metering vs. incident metering is to determine the contrast range of a scene. An incident meter reading won't tell you that. Also, for various reasons it may not be possible to get your incident meter into the same lighting as your subject (you're standing on the shaded bank of a raging river, and your subject is midstream in full sun, etc). That's when folks who understand how to use various types of metering use spot over incident. The reason most people don't use incident is that they've been trained by their camera with built-in TTL metering to rely on the in-camera meter and when not using an in-camera meter, they default to the same style of reflected light metering- if it's good enough for the camera, it must be good enough for me too.

I do agree with you on the reason and that spot metering is a useful tool on occasion.

I would note though that BTZS users determine contrast with incident meters all the time and if I'm on the bank of that stream with my incident meter it is normally easy to say "I'm standing in say zone II light" and adjust just as I might with a spot meter. I have yet to find a situation where an incident meter can't do a good job.

 

[benjiboy]

I do agree with you on the reason and that spot metering is a useful tool on occasion.

I would note though that BTZS users determine contrast with incident meters all the time and if I'm on the bank of that stream with my incident meter it is normally easy to say "I'm standing in say zone II light" and adjust just as I might with a spot meter. I have yet to find a situation where an incident meter can't do a good job.

I agree with you again Mark, and I own two spot meters but use them very little.

 

[DREW WILEY]

I can't imagine using anything but a spot meter for the very critical multiple readings I routinely make
unless wide varieties of outdoor lighting carrying completely different films. Highlight and shadow
placement are critical (analogous to Zone System work with black and white film - I want to know
exactly where the film kicks off the toe of the curve, for instance). One subject might be very close,
requiring bellows length compensation, filter factor, all kinds of stuff easy to calibrate using the Pentax spotmeter ring. With the wind howling and a lighting cloud about fifteen minutes away atop
a 12000 foot pass, there are enough things to go wrong using a view camera without adding exposure errors. With color chromes at something like twenty dollars a pop right now for 8x10 there
are no second guesses. Taking the same discipline into color neg work (at the same expense and]
rising all the time) essentially forces one to do things correctly, and not to guess using latitude BS
or generic overexposure formulas. When I'm street shooting a Nikon, I will bend the rules somewhat.

 

[markbarendt]

Drew, you are "special".

Siriously though, you really are describing a special case/use with no safety factor other than what you decided on from your testing.

 

[DREW WILEY]

Yes, and very critical testing at times. But just depends. Exact metering can be very important in certain situations, not in others. Depends on the specific film, lighting ratios, color temp, and expectations. If I'm out walking in a heavy rain with the Nikon tucked under my parka, I'm probably
going to choose a film with some forgiveness. And sometimes around here the fog will give an almost
perfect softbox lighting for part of the day, but then once the fog breaks, you can get very contrasty conditions which demand precise shadow and highlight placement, if one chooses to
shoot at all. In between you might get overcast lighting needing color temp correction using filtration. I expect to encounter all three tomorrow. Like I already said, it's far more important just to
get accustomed to your specific meter and chosen film in the first place. But with the film choices
changing rather quickly nowadays - or if you work with multiple films like I do - having a spotmeter
available is good insurance.

 

[DREW WILEY]

Per "safety factor"... That is something one automatically gives up once high-contrast or high saturation films are involved. Once someone is accustomed to something like Velvia, any color neg
film is going to be a piece of cake for determining exposure. But in the latter category, Ektar is going
to be distinctly fussier than Portra 160 or any of the amateur films. In black and white, just try
getting sparkling snow highlight in direct sun on the same TMX negative as deep shadow detail at
high altititude. It's easy with a spotmeter or ample experience, but would be pretty trick otherwise.
Even TMY is fussy in this respect. But the reward is very crisp separation of values over the whole
film curve. If you want life easier, then choose a film with a more gentle toe and lower relative
contrast, like FP4 or ACROS. Snapshooter might want something even more forgiving, like HP5 or
Delta 3200. There is no such thing as one shoe size fitting every foot.

 

[Diapositivo]

The Original Poster is going on holidays and he has shot so far only a few films. Nonetheless, he chose to only carry film with him, which is very nice to hear! Let's encourage him with practical and sound advice so that he might be a very happy film user also in the future and so that his "inexperience" with film will not damage his photography.
In a line, let's try not to scare him with too much technical details about zone placement, spot metering, color temperature, lighting ratios etc

To the OP I'd say: don't worry too much. Don't worry at all. Colour negative film is ultimately very forgiving. It's certainly easier to use than digital. With digital it's much easier to blow highlights in high-contrast situations. Film simplifies life! Correct and well thought-about exposure certainly gives better results but during holidays very often there's no much time to think too much, e.g. when going around with a group of persons, on a guided tour, a boat etc. In those situations negative film is the safest choice.

A few more suggestions: be careful of heat. Don't let the camera or film let's say in a glove compartment under the sun or in the boot of a car. Keep the film "fresh" when possible. Establish a clear "convention" for used canisters (impressed canisters) and virgin ones. I personally always rewind the film tail inside the canister to distinguish the impressed ones. Perfectionists will prefer to leave the tail outside of the canister (so as to minimize the risk of light leaks) but in that case be scrupulous in marking/separating the used ones. If you use a marker to mark canisters, make the marking immediately, before opening the new roll. Do observe the advice to change your rolls in shade. If you are in the sun in an open desert, do use your body to project a shadow on the camera while changing the roll. When you change canister do use your pump to dislodge dust particles from the inside of the camera. Always have spare batteries with you: don't leave them in the tent, or in the hotel. Find a place to have spare batteries always with you when you have a camera, things like your purse, your document holder, or a pocket of your photographic bag.

Fabrizio