Incident vs Reflected light in sun
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Who made mistakes? Sirus Glass? No he was just kidding I think.
Sirus Glass says that he shoots at box speed, my testing suggests that by pointing the dome at the subject he is overexposing by 2 stops, ISO 400 is now ISO 100. I was able to shoot at box speed using his method with my Sekonic with a disk insert that about 1/3 fewer holes than the standard insert, so maybe.
If the light is not very directional he’s going to have very little idea that anything is wrong.
That is the trouble with metering and negative film, that you can make rather big mistakes and 80 to 95 percent of the time get perfectly acceptable results.
You would however improve you photography generally by quite a bit on average by employing good practice. Better tonality and better highlight and shadow detail.
What you said is true but I think Sirus Glass was kidding. He knows better than that. I don't think he made the mistake.
Even if he did make the mistake, so what? We all have in our lives at least one thing that we've been doing wrong for many years without realizing it, and without consequences. I know I've had my share of "Oh my God! Is that how this is supposed to go? Can't believe nobody ever told me I was doing it the wrong way!". Part of life, part of human nature, and certainly no reason to shame anybody for it.
OP
OP
So, I took up the advice in the thread and found some time to play with my light meters. I discovered three interesting things:
1)
The difference in the sky is not more than one EV normally on a sunny day, sun not a point source, my bad.
2)
The Leningrad 4 does not use normal EV. The meter works very beautifully (It is the Gost version not the international/ISO version) If you transfer the measurement from the meter to the twisty dial you get a perfect shutter/aperture programme, but Sunny F/16 which has an EV of 15 reads as 11, even ignoring what the needle points at, just using the converter dials. So clearly the Gost version of the Leningrad 4 at least doesn't use the same EV scale as modern meters. Even eyeballing a picture of a Sekonic Twinmate L-208 I can see that, set to 16.5 it gives the same programme as the Leningrad 4 at 12.5, even ignoring the needle, so it's not the same EV scale, it's offset by a linear 4 I think.
3)
Placing the lumisphere (Actually a flat opalescent window) onto the Leningrad 4, outdoors, reduces the reading about 2.5 stops without moving the meter. This is surely the 2.5 stops that are lost when you flip the meter around to face the mid-grey/18% scene. So with lumisphere + pointing vaguely at sky gives the same reading as without lumisphere + pointing at concrete in the same light.
This last point is confusing because my digital meter is a standard LUX meter and even though it has a lumisphere it is calibrated to read the light directly, but the Leningrad 4 lumisphere/opalescent window drops 2.5 stops, and this is why you can use the result directly into the camera with the Leningrad 4 but not the standard lux meter.
Sorry to be Mr. Science, I should probably just shut up and photograph things, but this has really helped my understanding of how light behaves and how photographers use it.
1)
The difference in the sky is not more than one EV normally on a sunny day, sun not a point source, my bad.
2)
The Leningrad 4 does not use normal EV. The meter works very beautifully (It is the Gost version not the international/ISO version) If you transfer the measurement from the meter to the twisty dial you get a perfect shutter/aperture programme, but Sunny F/16 which has an EV of 15 reads as 11, even ignoring what the needle points at, just using the converter dials. So clearly the Gost version of the Leningrad 4 at least doesn't use the same EV scale as modern meters. Even eyeballing a picture of a Sekonic Twinmate L-208 I can see that, set to 16.5 it gives the same programme as the Leningrad 4 at 12.5, even ignoring the needle, so it's not the same EV scale, it's offset by a linear 4 I think.
3)
Placing the lumisphere (Actually a flat opalescent window) onto the Leningrad 4, outdoors, reduces the reading about 2.5 stops without moving the meter. This is surely the 2.5 stops that are lost when you flip the meter around to face the mid-grey/18% scene. So with lumisphere + pointing vaguely at sky gives the same reading as without lumisphere + pointing at concrete in the same light.
This last point is confusing because my digital meter is a standard LUX meter and even though it has a lumisphere it is calibrated to read the light directly, but the Leningrad 4 lumisphere/opalescent window drops 2.5 stops, and this is why you can use the result directly into the camera with the Leningrad 4 but not the standard lux meter.
Sorry to be Mr. Science, I should probably just shut up and photograph things, but this has really helped my understanding of how light behaves and how photographers use it.
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Considering he is not replying and his immediate response; it wasn't a joke.
Too elaborate for him or anyone if it was.
It is funny however that one of the most snarky, selectively pedantic posters on here should make such a mistake. He will never hear the end of it, and rightfully so.
I won't be contributing however.
I just can't believe that he made such a mistake. I saw many of his posts. I am quite sure he knows better.
If he made a mistake it's fine. I don't dwell on it. I just can't believe he made such a mistake. I saw way many of his post and I am quite sure he knows much better than making such a mistake.
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+1. Add "condescending and mocking of others" to the description, and you've captured it perfectly. I suppose that I, too, would avoid this thread if I were him.
I am not avoiding it. I am getting a chuckle on the mileage my mistake has make.
I don't use my sekonic (incident light and zoom spot reflected light) the same ways for slide film, b&w negative film, or color negative film.
All that meters do, is telling us the amount of light they sense, but that doesn't mean they are always telling us the values we should use: they give us just a base to take decisions...
An incident reading under direct sunlight is OK for slide film, but not for b&w negative film. An incident reading under soft overcast light is OK for b&w negative film, but not precise for slide film. The dome must be inside in some situations, not just for two dimensional subjects: sun can fool domes depending on its position in the sky.
IMO handheld meters tend to care about highlights for slide film, so camera's reflected light meters often recommend a bit more exposure (half a stop, two thirds...), and that's fine for negative film, both for b&w and color.
In case of color negative photography, you can give it the right light, or twice, or three times, and the resulting negative is the same, and that's not the case of slide film or b&w negative.
The problem with b&w negative film is, it's an intermediate step where people can't see their accuracy while metering, both because it's not a positive, and also because it becomes a, b, c or d after small development differences.
And, many people print from mediocre negatives all their lives, trying to stretch things while printing.
I don't talk about young students: it's common among teachers and other "experts" too.
All that meters do, is telling us the amount of light they sense, but that doesn't mean they are always telling us the values we should use: they give us just a base to take decisions...
An incident reading under direct sunlight is OK for slide film, but not for b&w negative film. An incident reading under soft overcast light is OK for b&w negative film, but not precise for slide film. The dome must be inside in some situations, not just for two dimensional subjects: sun can fool domes depending on its position in the sky.
IMO handheld meters tend to care about highlights for slide film, so camera's reflected light meters often recommend a bit more exposure (half a stop, two thirds...), and that's fine for negative film, both for b&w and color.
In case of color negative photography, you can give it the right light, or twice, or three times, and the resulting negative is the same, and that's not the case of slide film or b&w negative.
The problem with b&w negative film is, it's an intermediate step where people can't see their accuracy while metering, both because it's not a positive, and also because it becomes a, b, c or d after small development differences.
And, many people print from mediocre negatives all their lives, trying to stretch things while printing.
I don't talk about young students: it's common among teachers and other "experts" too.
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What is your idea of an ideal printable negative?
Hi Juan. I have a meter but have switched to my digital camera to assess exposures when I started shooting 4x5. I shoot Tmax BW negative and Velvia 50 chromes. I'm still practicing and trying to pin down a "foolproof" method. But it goes something like this.
I frame the picture I want to shoot with the digital camera. I set the aperture on f/22 when shooting 4x5 film in Aperture priority mode. I check the histogram and "blinkies" as well as the back display of the picture.. I reduce the opening a fraction of a stop when shooting chromes to avoid clipping. I add a little when shooting negative film, to avoid too dark shadows. I seem to be getting it right most of the time. What do you think about those procedures? Any recommendations?
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I was going to say this is wrong (it is wrong) but I see now that CMoore (and Sirius Glass for similar mis-statement) is an actual, admitted mistake.
For the record, I believe that when a meter is in incident reading mode with a white dome sensor active, the best practice is to be at the subject and aim towards the camera.
I have to be careful sometimes with my Sekonic because sometimes the wrong sensor is active and it's like I took a spotmeter reading out of my ear.
Alan. Try shooting two sheets: one with your “adjustments” and one without. Often you will find both acceptable… probably more often than not.
I too (used to) do something similar and because I use the histogram there is no need for the spot metering mode. First I make sure the ISO and the aperture are the same on both cameras. Then I set my camera on manual and multi (matrix) metering, adjust the shutter until I get the histogram weighted to the right, almost clipping. I only shoot b&w negative film. What I found is that I get the same exposure values that my incident meters read, so I just carry my phone now with an incident meter app (which gives the same readings as my Gossen DigiPro).
I pretty much just shoot "Street Photography, B&W neg film. I rarely use my handheld incident.
I SHOULD shoot a roll of several scenarios, one with the camera meter (reflected) and one with my incident and see how that transfers to the darkroom.
Hi,
I did a lot of slide film. In third year slide film was used at my school to make students be sure about exposure, after two years of B&W negative film.
Slide film and E-6 are sooooo easy because a) you see the positive, and b) there's just one possible development.
It's this simple: incident metering for direct sunlight. Your highlights will be perfect. Comment: you can open a third or half a stop if you want more open skin, as for fashion. You can close a third or half a stop if you have no skins and you want the highest color saturation.
For overcast or shadows (soft light) we don't reach clean whites after an incident reading: you"ll need a little more light. Do a 7 frames strip (bracketing) in thirds, from 1 stop overexposure to 1 stop underexposure (under soft light) and the same under direct sunlight, both incident metering, and you'll see perfectly what you need to decide after your own meter reading.
B&W film is totally different. There are two fields: a) adjusting your scene contrast to a single sheet, and b) mixing scenes of wildly different contrast in a roll, so for mixed scenes we need a short development to be able to print sunny scenes without blocked highlights, and we just expand the contrast of soft scenes with higher contrast multigrade filters while printing. Both work. Of course in the mixed scenes case, the shadows of sunny scenes are a bit darker than if we do sun perfectly for a sheet.
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One that wouldn't be better with a) more exposure, b) less exposure, c) more development, d) less development.
That also means: one that makes the best direct print (no dodging or burning) when base+fog reaches pure black.
All incident readings are taken next to the main subject, with the dome aiming at camera.
If the main light source is close to the zenit, the dome should be recessed, because part of that light is not reaching the vertical surfaces of your subject: if the dome is out, it will sense too much light.
That's why sometimes our cameras ask for more exposure than our incident readings... That, and the fact that incident metering is the way to meter for slide film in sunlight, so the system cares about easily burnt positive highlights.
If the main light source is close to the zenit, the dome should be recessed, because part of that light is not reaching the vertical surfaces of your subject: if the dome is out, it will sense too much light.
That's why sometimes our cameras ask for more exposure than our incident readings... That, and the fact that incident metering is the way to meter for slide film in sunlight, so the system cares about easily burnt positive highlights.
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===> For the record, I believe that when a meter is in incident reading mode with a white dome sensor active, the best practice is to be at the subject and aim towards the camera. <====
... or in similar light.
MattKing
Moderator
An unusual take on the "take a reading off of the palm of one's hand" approach.
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