'M' film speed dial

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seifadiaz

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Is the film speed dial of an M6 serves as a reminder only and no effect on the camera meter?

I am a new owner of an M6 classic and I forgot to set the film speed dial (ISO) when i changed films from XP2 400 to Superia Reala 100. :bang:
 
the camera's meter needs to "know" the film speed, just like any meter, to give a 18% gray card-based reading. ergo the iso dial. you've probably got some 2-stop underexposures on your reala, depending on the light you were shooting in. strong narrow beam stage lights? you might be okay :)
 
The original dial on an M door had a rotating pointer. Subsequent non-metered Ms such as the M4-2 had a fixed reminder with no moving part. The M6 rear flap ISO "reminder" again has a rotating central disc that sets the ISO for the meter (see the gold electrical contacts inside). It seems like you already know this in essence.....?
 
MCTuomey said:
the camera's meter needs to "know" the film speed, just like any meter, to give a 18% gray card-based reading. ergo the iso dial. you've probably got some 2-stop underexposures on your reala, depending on the light you were shooting in. strong narrow beam stage lights? you might be okay :)
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Sorry to cut in with a hijack and a flat contradiction, but 18% grey cards have very little to do with anything in exposure except perhaps some spot meter 'mid-tone' indices: http://www.rogerandfrances.com/subscription/ps 18 per cent.html. Again, my apologies, but this is a bit of a hobby-horse of mine and I always try to counter false impressions about 18% grey when I find them. Perhaps I feel so strongly because I once believed these myths myself, and I believed them because they are so widely propagated.

Cheers,

R.
 
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It is not a myth that I metered the palm of a hand, added one stop, and got perfectly exposed slides. It is not a myth that I added 2.5 stops to the reading off white paper. My conviction is that I should have done as well if I had had a grey card.
 
Roger, am I wrong in thinking that the meter in the OP's M6 is calibrated to deliver combinations of shutter speed and aperture that will approximate an average 18% GC tone over the metered area? If I am not wrong, why is there a problem with my reference to the 18% gray card?

Apologies to the OP for this diversion ...

Mike

Roger Hicks said:
Sorry to cut in with a hijack and a flat contradiction, but 18% grey cards have very little to do with anything in exposure except perhaps some spot meter 'mid-tone' indices: http://www.rogerandfrances.com/subscription/ps 18 per cent.html. Again, my apologies, but this is a bit of a hobby-horse of mine and I always try to counter false impressions about 18% grey when I find them. Perhaps I feel so strongly because I once believed these myths myself, and I believed them because they are so widely propagated.

Cheers,

R.
Click to expand...
 
I didn't exactly agree with Mike's way of putting it, but neither do I see Roger's 'myth' of the grey card? What's the myth? I looked at Roger and Frances's site as referred to above and I come up with much the same as what Payasam alludes to succinctly: the use of some sort of uniform reflective surface, including one's hand, allows for a measure of the light falling on the subject instead of the light reflected from the subject. If one uses a grey card, what would one have to say about its use to fall into the supposed trap inspired by the 'myth' that Roger refers to? Is the myth just that 18% is not the reflectivity of the average scene? The statement that these cards have nothing to do with exposure seems to go a lot further than that. I have never used one by the way, but use my hand with the M6 regularly if I don't have my incident meter with me.
 
Richard, in a long-ago post I called this technique the poor man's incident meter. Silly, of course, because this poverty comes with a meter built into one's camera. I might confess, by the way, that I have never even seen a grey card with 18 per cent reflectivity.

Perhaps, if we stick around, someone will "counter false impressions about 18% grey". Can't be easy, as there are no false impressions...
 
Richard G said:
I didn't exactly agree with Mike's way of putting it, but neither do I see Roger's 'myth' of the grey card? What's the myth? I looked at Roger and Frances's site as referred to above and I come up with much the same as what Payasam alludes to succinctly: the use of some sort of uniform reflective surface, including one's hand, allows for a measure of the light falling on the subject instead of the light reflected from the subject. If one uses a grey card, what would one have to say about its use to fall into the supposed trap inspired by the 'myth' that Roger refers to? Is the myth just that 18% is not the reflectivity of the average scene? The statement that these cards have nothing to do with exposure seems to go a lot further than that. I have never used one by the way, but use my hand with the M6 regularly if I don't have my incident meter with me.
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I didn't state it well. What I mean to say, Richard, is that my understanding is that reflectant meters (as in an M6) are calibrated to calculate an exposure for the metered light equal to a mid-tone (average of the scene or what is represented on an 18% grey card). Is this not true?

If you use your hand as the surface from which to reflect ambient light, take a reflective meter reading, and then use that reading, you will not get the equivalent to an incident meter. You will need to add a stop of exposure to get the equivalent to an incident reading. That's because your caucasian (?) skin isn't a mid-tone; it's Zone VI. The meter doesn't know that, so it assumes you want whatever light is bouncing into it is supposed to be average, or Zone V. Am I off-base here?

Mukul would agree with this view, I think. He adds a stop of exposure to his reflective hand reading.
 
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Mike, of course you understand all this perfectly, but the way you put it seems wrong to me. Maybe I am being obtuse. I have read and re-read your post and Roger's. I don't think of the meter giving me a reading that is calculated for an 18% grey card or a mid-tone or calculated for anything. For any scene my M6 meter, which is a great meter, gives me a reading of what is reflected, period. It's up to me to decide if that reading is likely to expose this subject well, and if it's an average scene then it will. It's me that does that calculation, not the meter. In the case of a dandelion in front of a blackboard I would need to know better than the meter. I am probably not saying anything different, but I do find this way of thinking about it is easier to teach my children and others. If I am being unreasonable I don't mean to be. Maybe this is getting close to the myth that Roger alludes to...? The hand / paper / card are just ways to use a reflected meter with something familiar to get around the misleading readings from non-average scenes.
 
Richard, I think we agree. We just say it differently. We use the meter as a starting point, that's all. Nothing unreasonable about it :)
 
Mike, I must point out that race has nothing to do with the colour of the palm of a human hand. Palms are pretty much the same across the races. Things would be different if people metered off the backs of their hands.
 
I understand it the same way and that is what is written in the Leica M7 manual: All exposure meter (reflective meter) are calibrated to a grey-tone that represents18% reflection of all incoming light. In other words, positioning a 18% grey card in front of the subject so that it is lit in the same way as the subject, should give the correct exposure.


MCTuomey said:
the camera's meter needs to "know" the film speed, just like any meter, to give a 18% gray card-based reading. ergo the iso dial. you've probably got some 2-stop underexposures on your reala, depending on the light you were shooting in. strong narrow beam stage lights? you might be okay :)
Click to expand...
 
Just a few words: that kind of reading (reflected) only works sometimes...

The light you read that way, depends of the kind and harshness of that light, and also on the angle of incidence on the card or skin. Payasam is right about it works sometimes, and Roger is right about it doesn't work sometimes.

Cheers,

Juan
 
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