Metering slide film +2 and -2 over and under midtone.

rayonline_nz

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I have been reading and watching re: metering with slide film which has a 2 stops over and under ability to capture the information. Then some people use the average function on their light meter after metering the highlight and the shadows.

What happens if the scene has 1 stop under midtone and 3 stop over? Does the slide look underexposed but the details are still captured?


Thanks.
 

benjiboy

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If the exposure is three stops over a mid tone you have to decide if you want burned our highlights or blocked up shadows and which you give priority to. Many people who shoot negative film don't appreciate that with slide film which is a positive film the more the exposure you give the film the lighter the image is.
 

Doremus Scudder

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When I shot transparency films, I always based my exposure on a highlight. I would choose a white that I still needed detail in and place that at 2 stops overexposed (or in Zone VII in ZS parlance). Shadows fell where they were; I would rather have too-dark shadows than blown highlights for transparencies.

Best,

Doremus
 

Poisson Du Jour

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If you have metered and locked-in a mid-tone reading, and you come up with an unbalanced assembly of readings on averaging, then the simple straightforward task is to shift the midtone reading which will also in effect shift the averaged balance. But the scenario you have described hints at poor metering technique: you have metered parts of the scene that are two dark (stacked) and which cannot be balanced relative to the rest of the scene. A mid-tone value comes first (or use a greycard to be sure you have an actual midtone), and it is locked in as a reference point. Then a bright part of the scene, but not the brightest area of the scene. Then meter a dark but not the darkest area of the scene (if you take multiple readings here you will dramatically overexpose transparency film). Then average all. A reading 1 to 1.5 stops off-balance either + or – is of no seriious consequence, and is indicative of shadow and highlight area, but the scene should still be examined to ensure that you are working within the range of the film so you can achieve some detail in both highlight and shadow components. A common problem I see is people overexposing shadows, in the process completely destroying highlights andn midtones.

The method I have described here is that which I have used for a very long time with the Sekonic L758D multispot meter using Velvia for all imaging (and Provia 100F for pinhole work). There is additional leeway in metering with Provia 100F.
 
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rayonline_nz

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Thanks.
I was just thinking of a possible theoretical situation, hackable way, maybe not. Maybe like a high key image or a hazing washed out scene.
Like if the scene had more highlights than shadows. For whatever reason. Drop the mid tone down one, so that leaves 1 other step for shadow and 3 steps for the highlights (including 1 for midtone).
 

Poisson Du Jour

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That example is workable, but you may still sacrifice something. A live experiment should be undertaken (and take notes!) to ascertain how well this can work.
I have often had an unbalanced reading and pushed on cautiously, which meant I had to make do with slightly darker areas where I wanted more detail, but of course at the expense of the also desired highlights. It is a balancing act!

There is one other thing. If you are printing colour transparencies via non-traditional means e.g. hybridised, a slight 0.5 to 1.0 stop "key" is usually a good idea as some brightness will be lost (or flattened) at the print step. In this regard a scene that you are sure to want to print should be bracketed at normal, +0.5 and +1.0. Any more than that will risk highlights.
 

mrred

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If I were shooting to project, I would use standard metering and call it a day. The projectors do a good job pushing through the shadows. If you are doing something else with it, any shifting of the exposure could take advantage of lesser DR in post.
 

DREW WILEY

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Depends which parts of the scene you want color saturated in. After awhile, you just get experienced enough to know what kinds of lighting will
match the scale of the film. Otherwise, if contrast to is simply too, much, you're going to have to sacrifice shadow detail to black, since that is generally less annoying in a chrome than washing out the high values. Likewise, one just gets accustomed to a certain metering style. I have worked
exclusively with spotmeters for all types off film and cameras for over thirty years now; but prior to that, I used basic averaging meters with complete success for slide film. I'll just add, that if you intend to have an image printed, exposure has to be more accurate than for just a slide show.
 

Bob Carnie

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I have processed a lot of E6 in my past life- here is a trick if you have a reputable lab to work with and their plots are historically spot on, casual E6 labs forget this trick.


Consider a 1/ 2 push process as normal and expose your film, clip test or run a test roll at push 1/2 - If you require you can drop process back to normal and you can salvage a strong scene.
This allows you 3/4 drop potential without worrying about colour shift.
Drop process past 1/2 on most Refremas start introducing colour cross over but you can push process more liberally and keep good colour. therefore make push 1/2 your normal . If you are clipping then run the film right after the process within the same day. This is one reason why most top end E6 labs are open late- The ability of running a clip then processing in the evening.
 

Diapositivo

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2 EV above middle-grey is where you still get all the texture. Above that the shoulder begins and the texture begins being lost, slowly, gradually.
So one should know what the situation really is.
Let's say a model with a white jumper and a darkish hat, and 4 EV in difference of reflectivity between jumper and hat (model skin somewhere in between).
The jumper will be rendered white and textured also if placed, let's say, at 2.3 EV above middle grey (you measure the jumper, and you open 2.3 EV more than what the lightmeter tells you).
The hat will fall 1.7 EV below middle grey (because it was 4 EV below the jumper, in your hypothesis) which is still full of details. It might appear a bit darker than what you "saw" it but unless the hat is a "reference" dark grey well known and which must recogniseable in the picture (let's say a trademark that you want to render with an exact tone) you don't care much.
Or you could place the white jumper at +2 above middle grey and the hat will fall 2 below middle grey, in this case you sacrifice the tone of the hat (you place it a bit darker) but you are sure you get all the texture of the jumper.
If this is a catalogue picture of the white jumper, +2 EV above middle grey will preserve all the details and would maybe be preferable. If the girl is the subject, you sacrifice some little detail in the texture of the jumper, you can expose the white jumper for +2.5 or so, you don't care about preserving all the texture in the jumper. Actually if the girl is the subject I would use an incident-light meter in front of the girl, a spot-reflected light meter on the jumper, and worry of the jumper only if it is let's say 4 EV above middle grey (some parts of the face in the shade, some part of the jumpes in full light). Else I wouldn't worry at all, in uniform light the jumper will be rendered with good details in any case, due to the shoulder behaviour of the film.
 

DREW WILEY

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Nonsense. Talk to the people who repair meters in Hollywood, or to a few cameramen. Spotmeters are routine. There might be certain exceptions, but spot meters are the easiest way to pin down the difference between high and low, not just the middle. Reversal film is damn near dead as a dodo
anyway, and has been for quite awhile. That link your provide is conspicuously out of date and superficial anyway.
 

darkroommike

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Diapositivo

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Man, what did you eat for breakfast? I'm going to eliminate that from my diet!
 

wiltw

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darkroommike said:
Amen. The incident light meter is the king of cinematography.
Click to expand...


To Benjiboy and darkroommike...do not forget that the movie industry LIGHTS so that the DR of film can capture the DR of the scene, Similarly a commercial photographer LIGHTS the set so that the DR of the scene fits within the (even narrower than transparency film) DR of the offset printed page so the client's image will present well on the product brochure.
Yet as photographers shooting in nature, we cannot light our scene the way we want, and we often need to know the DR of the scene -- which might be 12EV or more -- so that we can decide which part of the scene we choose to let fall outside the range of our film.
A spotmeter lets us know the DR of the scene, while the incident meter simply tells us what exposure value properly captures midtone density in the middle of the film's range of brightnesses. So an incident meter is great when we know our scene falls within the DR of the film we are shooting, else we need to use a spotmeter to find out how wide the scene DR really is.

To Drew...color transparency might be getting thin in the variety of emulsions, but APUG is indeed an 'analog' forum and not 'd*gital' and therefore continued discussions of color transparency remain valid. Even CINEMA shooters are staging a revival of FILM rather than d*igital capture and distribution of feature movies.
 
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benjiboy

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Diapositivo said:
Man, what did you eat for breakfast? I'm going to eliminate that from my diet!
Click to expand...
He just made my ignore list too, I have two digital 1 degree spot meters and still find incidental light metering better because it's a highlight meter, I hope his rabbit dies and he can't sell it's hutch
 
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DREW WILEY

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The biggest alt movie venues in the country are smack up the street. The new Pacific Film Archive looks like an oversized DeLorean from Back to the
Future, and is otherwise a giant hole in the ground that cost hundreds of millions of bucks. I wonder how many students can actually afford to attend events now that their tuitions have been jacked thru the roof to pay for luxuries like this. There were probably numerous donors, however. Redford has been pushing for it for years, and even wanted to level the big restaurant complex across the street to do it in this part of town. Pushback. Food is still a notch up. Don't try serving rabbit, however; the animal rights people will plant a bomb on your wagon. They've already done it to biotech labs with rabbit cages. Otherwise, spotmeters can just as easily be used for midpoint readings as the boundaries of lighting. Just gotta be accustomed to them. They read anything - black rabbits, white rabbits, polka-dotted rabbits....
 

wiltw

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For this discussion, let us assume that all listed levels have DETAIL (not 'detailess black' nor 'detailess white'
  • BOLD BLACK = midtone density captured as 'midtone' (18%) in bright sunlight
  • BLUE = where we put our exposure (when not at 0EV)
  • brackets [ ] = what our film DR can cope with (assumed to be 7EV for discussion purposes)
Now let us discuss various scenarios...
  1. a 'normal scene' with range of brightnesses: [-3EV -2EV -1EV 0EV +1EV +2EV +3EV]
  2. a scene which also includes dark details in areas which are not lit by direct sun:
    -5EV -4EV [-3EV -2EV -1EV 0EV +1EV +2EV +3EV]
    we lose details in the shadows
  3. a scene which also includes dark details in areas which are not lit by direct sun, and we expose for shadows:
    [-5EV -4EV -3EV -2EV -1EV 0EV +1EV] +2EV +3EV
    we lose details in the highlights
  4. a scene with extra bright highlights from reflective metal, and we expose for highlights: -3EV -2EV [-1EV 0EV +1EV +2EV +3EV +4EV +5EV]
    so we lose details in the shadows
  5. a scene with details in dark shadowy areas not lit by direct sun AND also with extra bright highlights from reflective metal, but expose to show detail in darker toned aspects in the shade:
    [-5EV -4EV -3EV -2EV -1EV 0EV +1EV] +2EV +3EV +4EV +5EV +6EV
    we lose the highlight details.
OP question is about scenario 4...
a scene with extra bright highlights from reflective metal and with the bottom two (no items inherently black in photo):
  • -3EV -2EV [-1EV 0EV +1EV +2EV +3EV +4EV +5EV]
    When I expose as shown, 12% inherent tonality registers in the photo as 'almost black' and 18% inherent tonality records as 'very light grey'-- which is NOT its inherent tonality; this would upset a fashion/textile industry person who wants their fabrics to show correctly
  • [-3EV -2EV -1EV 0EV +1EV +2EV +3EV] +4EV +5EV
    When I expose as shown, 18% tonality is 'middle grey'... its inherent tonal, But I lose any detail in areas falling within the top two brightness zones. And there would have no blacks present in the photo. A fashion/textile industry person who wants their fabrics to show correctly (modelled by the fair skinned Danish lass) would be happy, though.
 
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DREW WILEY

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A lot also depends on what you intend to do with your shot. A slide show? Scanning at home versus a professional drum scan for reproduction? Printing it yourself? Having gone through purgatory learning how to make very high quality prints from chromes in my own darkroom, I got a very
good feel for them, and how specific films might significantly differ from one another. You can't just make a generic statement about plus or minus
above or below middle gray. It all depends. Best to stick with one specific film for awhile until you get used to it. That shouldn't be hard, since so few
chrome films are made anymore. But when you run out of wiggle room, most chrome shoots sacrifice the lower tones to pure black rather than washing out the lighter values.
 

Diapositivo

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My fast answer to the original question anyway can be rendered this way:

IF the light on the scene is uniform, an incident-light meter will give you exactly what you expect from the slide (will be centered with the midtones where the human eye places them) EXCEPT the case when your important subject is white or black.
If your subject is white (white jumper, flour, sugar, ice-cream etc. you want it white but you want the full texture on it) then you place your subject at +2EV above middle grey (i.e. above what the spot-meter will tell you).
If you use an incident light-meter, in this case you cannot know exactly where on the film the white subject will be placed. The normal behaviour would be to close 0.5EV so that your white subject falls somewhere at +2EV above middle grey.
(middle grey = 18%. 2 EV above that is 72%, a surface with 72% reflectivity appears white. Your ice-cream might have 90% reflectivity and if you use incident metering that would place it somewhere above the "full-texture" zone of your slide film. So you just close a little bit. A heap of flour, sugar, an ice-cream, some snow etc. is recognized by human brain as "white" even if it is not milk-white on the slide, so you let the brain do the trick and worry more about texture than about "pure white").

If your subject is black (a black pair of shoes, a tuxedo) you to the opposite and open a bit more, to preserve the texture. The human brain will reconstruct the shoes, the tuxed as being "black" even though, in the picture, they are "very dark grey".
 

DREW WILEY

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You mean mud, not black. I want to know the difference when I take the shot. That's the kind of thing spotmeters are really good for, provided you
understand the film and your output media too.
 

Poisson Du Jour

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DREW WILEY said:
You mean mud, not black. I want to know the difference when I take the shot. That's the kind of thing spotmeters are really good for, provided you
understand the film and your output media too.
Click to expand...

That first five words of that statement are as clear as mud. What are you referring to??
 

benjiboy

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If you use the "Duplex Method" I use with an incidental meter as described in The Exposure Manual by Dunn & Wakefield pointing the dome at the sun or main light source then from the subject to the camera and averaging the two readings it gives an extremely high percentage of acceptable exposures on transparency films regardless of the direction of the light, front, back or side without trying to use the Zone System, which was devised for monochrome film is unsuitable to be applied for colour slide film that's a completely different ball game. I've been using The Duplex Method for more than thirty years and it works for me .
As you write one can use a spot meter to get an idea of the subject brightness range if you wish to see the films ability to reproduce it my Kenko KFM 2100 ( Minolta Auto meter V1) can do this with ease, but Duplexing gives me better results because my slides are a constant density for projecting slide sequences and you don't go from a light to a dark image on the screen.
 

benjiboy

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Alan Klein said:
When I shoot landscapes, I bracket one stop above and below using Velvia. Sometimes I'll use 1/2 stop. By the way. Why are some of you using a digital light meter? This is APUG. You should use an analog meter!
Click to expand...

My steam powered light meters (Weston Euro master, and Gossen Profisix) have been retired to my sock draw Alan, I love my modern digital meters, but I don't own a digital camera at least I draw the line at that, which is more than some members of this forum can say
 
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