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Thread: Exposure problems

  1. #1
    Paul66
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    Exposure problems

    I really like my new Mamiya but....... I am having issues with the exposures it is giving me, I am metering with a Seconic L358 and I set the camera to the exposure it says and the in=mages are all very dark if I fix the problem in post it makes the images grainy, what am I doing wrong??????

  2. #2
    Shelby Lewis
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    Re: Exposure problems

    I can only venture a few guesses...

    Firstly, you can't trust that the Sekonic and Mamiya are calibrated together until you've checked it yourself. My sekonic (same one) is pretty close to my Aptus II6, but worlds away from my canon 5dII (since canon doesn't rate ISO to the true standard). So a simple fix might be to try and calibrate the two such that the two are in agreement.

    Also... are you sure the back's ISO setting is what you think it is? Sounds silly, but I sometimes shot at ISO50 when I thought I was at ISO 100 simply because I had no in-viewfinder reminder like with my 35mm gear.

    Mechanically... it could be a sticky shutter mechanism or something similar, but we'd more details to start narrowing the choices.

    I can say this, I never trust the image on the back of the LCD as a judge for accurate exposure on my aptus... only the histogram. It was always different once I got it into the computer than I thought it would be if I just chimped and hoped.

    Shelby

  3. #3
    Paul66
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    Re: Exposure problems

    I plan on calibrating today so we'll see, I did a shoot yesterday and didn't trust the LCD and got home to see it wasn't wrong everything was under exposed. The light meter was dead on with my 5D mark2, hopefully I can fix this with a simple calibration.
    Thanks for responding

  4. #4
    Senior Member johnnygoesdigital's Avatar
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    Re: Exposure problems

    I'm not sure about the Phase, but make sure there's no exposure compensation set to a pre-determined level. Also, the metering could be set to spot, when you might need average only. I've sometimes forgot to change the metering mode in my Sekonic, and it was measuring a very small 1 degree area.

  5. #5
    Administrator Bob's Avatar
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    Re: Exposure problems

    grainy images in post show that the files were boosted too far.
    Trust the histogram, only trust the histogram in the field.
    -bob

  6. #6
    Paul66
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    Re: Exposure problems

    Yeah I know that Bob, what I don't know is why I'm having to do that, my wife thinks we should buy a new meter but I don't want to waste money when this one has always been dead on before.

  7. #7
    Paul66
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    Re: Exposure problems

    Oh and this only happens when shooting with strobes

  8. #8
    Senior Member Thierry's Avatar
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    Re: Exposure problems

    Paul,

    You don't need to buy a new light-meter, it would be much more precise and easy to use the histogram. It couldn't be more precise.

    Thierry

    Quote Originally Posted by Paul66 View Post
    Yeah I know that Bob, what I don't know is why I'm having to do that, my wife thinks we should buy a new meter but I don't want to waste money when this one has always been dead on before.
    Thierry Hagenauer
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  9. #9
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    Re: Exposure problems

    Why a meter? I agree with the others, use the camera to determine exposure, which will be far more accurate.

  10. #10
    Paul66
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    Re: Exposure problems

    Shooting natural light yes it works great, with studio lighting not so much.

  11. #11
    Senior Member Thierry's Avatar
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    Re: Exposure problems

    Of course it does also with studio light, Paul.

    You have the most fantastic and precise light-meter with the histogram, one each zone-system user would have dreamed to have 20 years ago. You can meter each single point of the scene, to the pixel and get precisely the exact density you which to have.

    Thierry

    Quote Originally Posted by Paul66 View Post
    Shooting natural light yes it works great, with studio lighting not so much.
    Thierry Hagenauer
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  12. #12
    Administrator Bob's Avatar
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    Re: Exposure problems

    Quote Originally Posted by Paul66 View Post
    Oh and this only happens when shooting with strobes
    Ah ha! a sync problem.
    Are you shooting on "X" what shutter speed, which strobes?
    -bob

  13. #13
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    Re: Exposure problems

    "You can meter each single point of the scene, to the pixel and get precisely the exact density you which to have."

    How do you do that with a IQ back?
    I know you can do that tethered, but to a CF card???

  14. #14
    Paul66
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    Re: Exposure problems

    Shooting Manual mode1/125 f5.6 ISO50 and using Elinchrom 600RX's it's not like the shutter didn't open all the way they just look under exposed.

    I really don't want to use lights without metering, I know a lot of people do it but I feel more comfortable using the meter, might have to change that though ha ha

  15. #15
    Administrator Bob's Avatar
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    Re: Exposure problems

    Quote Originally Posted by Paul66 View Post
    Shooting Manual mode1/125 f5.6 ISO50 and using Elinchrom 600RX's it's not like the shutter didn't open all the way they just look under exposed.

    I really don't want to use lights without metering, I know a lot of people do it but I feel more comfortable using the meter, might have to change that though ha ha
    I have those same lights as well as some pack lights.
    Do me a favor and switch to X 5.6 ISO50
    thanks
    -bob

  16. #16
    Senior Member Thierry's Avatar
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    Re: Exposure problems

    I don't know where in the menu of the IQ's, but there is (should be) a feature to measure each point of the preview and get its transcription in the corresponding histogram of the image, giving the position of this particular point on the whole scale from the shadows to the high-lights, with even the value in EVs. It is even possible to measure that way each color channel separately.

    Thierry

    Quote Originally Posted by Willow View Post
    "You can meter each single point of the scene, to the pixel and get precisely the exact density you which to have."

    How do you do that with a IQ back?
    I know you can do that tethered, but to a CF card???
    Thierry Hagenauer
    [email protected]

  17. #17
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    Re: Exposure problems

    I know Leaf has something like that, but not P1 I think.

  18. #18
    Senior Member David Schneider's Avatar
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    Re: Exposure problems

    You might also see the difference with the L358 if you have the globe in the out position or the in position.

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    Re: Exposure problems

    I know it sounds like daft question, but do tell how you meter.

    (and yes, Shelby is right they are calibrated differently, thats why 758DR is best thing to have, as you can calibrate it to camera that you use, but still.. It shouldn't be farther than 2/3 Ev out).

    And secondly - posting image would help too.

    It doesn't look like you out on sync speed, and you should be well within power peak of lights. So culpit is either meter (does it work well for other cameras?) or , or metering technique, or some filter... or could it be LCC target that got stuck somewhere?

  20. #20
    Paul66
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    Re: Exposure problems

    Here is one of the files

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    Re: Exposure problems

    and what metering technique do you use?

  22. #22
    Paul66
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    Re: Exposure problems

    I don't understand what you all mean by what metering technique I use,

  23. #23
    Paul66
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    Re: Exposure problems

    If your talking about the dome in or out, I have always metered with dome in, I have never had an issue before.

    Also Bob I did as you ask and it worked fine, just confused me even more ha ha
    Also I have the Mamiya 645DF/ 28DM and 80mm LS

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    Re: Exposure problems

    Quote Originally Posted by Paul66 View Post
    If your talking about the dome in or out, I have always metered with dome in, I have never had an issue before.

    Also Bob I did as you ask and it worked fine, just confused me even more ha ha
    Also I have the Mamiya 645DF/ 28DM and 80mm LS
    Was the underexposure consistent? I noted a similar problem (X or M, DF, IQ back, LS80) using a hot shoe flash for fill, with a profoto air transmitter synced from the back. Images tended to be dark, but varied from what I expected to dark. Reducing exposure time made it worse so it was some timing issue between the hot shoe pulse and the output pulse.

    I think moving the sync to the DF sync port helped but, in the end, I just got rid of the on camera flash. The air transmitter works fine on its own.

  25. #25
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    Re: Exposure problems

    On a DF+Back setup the flash sync should be done from the DF body sync port.

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  26. #26
    Senior Member johnnygoesdigital's Avatar
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    Re: Exposure problems

    This might be odd, but check under the dome to make sure there's no dust on the meters measuring sensor. It's possible to have dust influence your meter. Also, make sure your drawing the correct amount of power from your lights, and that the elements are intact. Try taking readings with the dome up, facing the light to be measured and then at the lens. The camera's reflective meter should be fairly accurate - high contrast situations can sometimes fool a meter. In those situations I use the spot setting on the meter. With digital, you can keep changing the camera settings until it looks good, so try a combination of settings using the histogram, to match your desired result.

    I just looked at you posted photo, and it seems your lights might actually be too far away. Look at the lack of contrast or light falloff in the scene overall. Try moving your lights closer to your model. Remove and modifiers such as a soft box and baffles too, to experiment with output.

  27. #27
    Paul66
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    Re: Exposure problems

    I tried a friends light meter and it's dead on, not sure what happened with mine but I guess electronics just fail.
    Thanks for all the advise and thanks for not bashing my ignorance for tech terms, I am self taught and learned trial and error
    Doug are you sating the skyport isn't really compatible with the Mamiya?

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    Re: Exposure problems

    Quote Originally Posted by TH_Alpa View Post
    Paul,

    You don't need to buy a new light-meter, it would be much more precise and easy to use the histogram. It couldn't be more precise.

    Thierry
    Thiery is absolutely right here.

    Meters need to be calibrated to a standard, which assumes shutters, apertures etc also conform to said standard, blah, blah, blah. Frankly it's all crap when the only thing that matters is how much light is arriving at your sensor. Thankfully, your individual sensor's sensitivity is a constant, unlike the batch variation that our comrades at both Kodak and Fuji inflicted on us.
    I am a working pro who, in the days of film, carried a meter bag with a Minolta flashmeterIV, a Minolta Colormeter, a Minolta spotmeterF and the groundglass probe. With the advent of backs with histograms, I sold all my meters and have never looked back. Shoot a test frame, check the histogram and adjust from there. This is WAY faster and more accurate than any meter.
    If you are a picky SOB as I can sometimes be, shoot tethered. Then you can read the brightness levels down to single pixels to your hearts content.
    I shoot mostly with an Alpa STC and I have the most accurate meter ever made - the histogram on my IQ180.....
    Frankly, I don't understand why anyone who doesn't shoot film needs a meter.

    Stress less, shoot more!

    Cheers,
    Siebel
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    Re: Exposure problems

    Quote Originally Posted by Paul66 View Post
    I don't understand what you all mean by what metering technique I use,
    No, i didn't mean dome and stuff.. I mean if you were metering reflected light - what zone you were using , and if you were metering incident - how you aim meter..

    But no matter, if you said that your friend's meter worked fine.

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    Re: Exposure problems

    Quote Originally Posted by siebel View Post
    . Shoot a test frame, check the histogram and adjust from there. This is WAY faster and more accurate than any meter.
    Sorry. It is not faster nor more accurate. I been big fan of "test with histogram" for a while too, after having to deal with old and clunky minolta's and some old soviet meters.. And then i went back to real flash meters from Sekonic and never ever looked back.

    Histograms doesn't work b/c it not neutral enough, b/c you always have to remember what kind of scene's main tone is & etc.

    Then again. Different folks. Different strokes.

  31. #31
    Paul66
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    Re: Exposure problems

    Sergi, I point the meter at each light that I am metering.

  32. #32
    Senior Member Thierry's Avatar
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    Re: Exposure problems

    Dear Sergei,

    what do you mean with this?

    Thanks
    Thierry

    Quote Originally Posted by SergeiR View Post
    Histograms doesn't work b/c it not neutral enough, b/c you always have to remember what kind of scene's main tone is & etc.
    Thierry Hagenauer
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    Re: Exposure problems

    Quote Originally Posted by Paul66 View Post
    Sergi, I point the meter at each light that I am metering.
    Ah. So Collins school, like myself.. Not Lane&Co school.. I vouch for the funky electronics... Have seen this happening with friend's Minolta (ambient dead on, flash is one stop under), but never seen it with Sekonics..

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    Re: Exposure problems

    Quote Originally Posted by TH_Alpa View Post
    what do you mean with this?
    Typically histogram will display values according to current settings of contrast. Also per-channel histogram goes differently and calculated differently in camera/back from software (exception - i never compared new IQ series, and i never compared Phase One backs).

    Digital sensor do have linear response, unlike film, which is curved. Histogram on most cameras (i am sure there are exceptions, however i never seen it) represents curved response, thus displaying info that is not neutral to settings. Frank Doorhoff suggested at some point contrast -2, which is getting S-curve more flattened, thus approximating what is in RAW a bit better.

    Another interesting problem is channel sensitivity (which is included into the final histogram). E.g - if i shoot Leaf in friend's studio with Alien Bees (older ones) - they do have really really weird thing going in red channel. No matter how i fight it - i always end up with pretty terrible results for skin - it will look ok on back, but once i am processing it with C1 (or any other RAW software, i have few for different occasions) - goodbye skin texture, red channel goes out of control. Same stuff shot on ZD back - don't see it at all. Both backs with Elinchrom lights - never had a single issue.

    Granted - i have never ever taken electronic parts apart. And i don't have latest backs, which might have some cool new features.
    But i would much rather trust my flash meter and not waste shutter counts / batteries with camera, making scene ready before subject arrives on the set, than having to deal with whole thing on the fly. Plus, having light exactly where i want it and not "oh its within one stop, i will later fix it" - is much better. Not to mention that whole "i will later fix it" never truly yields good results as good.

    Or if you meant what i meant by main tone? Its just a whole zone thing. Shooting black cat on the snow, shooting white cat on black paper, shooting gray cat on gray paper... That kind of stuff. Having to remember to compensate and do whole zone placing b/c of reflected metering for histogram is not much of a picnic either (not like there is much choice for landscape of course, but at least for portraits there is)

    Just me. I learned to not trust histograms much, walking softly and carry around big stick once again..

  35. #35
    Senior Member Thierry's Avatar
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    Re: Exposure problems

    Sergei,

    Quote Originally Posted by SergeiR View Post
    Typically histogram will display values according to current settings of contrast. Also per-channel histogram goes differently and calculated differently in camera/back from software (exception - i never compared new IQ series, and i never compared Phase One backs).

    Digital sensor do have linear response, unlike film, which is curved. Histogram on most cameras (i am sure there are exceptions, however i never seen it) represents curved response, thus displaying info that is not neutral to settings. Frank Doorhoff suggested at some point contrast -2, which is getting S-curve more flattened, thus approximating what is in RAW a bit better.
    That is up to you, how you set the curve, linear, s-shaped, flatter in the shadows, steeper in the highlights, or vice-versa, etc ..., resp. with more or less contrast (this is simply equal to changing the developing process with film). The same can be obtained with film, in some ways, e.g. by changing the process, thus changing the contrast.
    It doesn't change anything concerning the precision of using the histogram as a light-meter, once you have the curve you want to use.

    Quote Originally Posted by SergeiR View Post
    Another interesting problem is channel sensitivity (which is included into the final histogram). E.g - if i shoot Leaf in friend's studio with Alien Bees (older ones) - they do have really really weird thing going in red channel. No matter how i fight it - i always end up with pretty terrible results for skin - it will look ok on back, but once i am processing it with C1 (or any other RAW software, i have few for different occasions) - goodbye skin texture, red channel goes out of control. Same stuff shot on ZD back - don't see it at all. Both backs with Elinchrom lights - never had a single issue.
    I don't see in which way this has influence on the light-meter and how precise it is. Film has never had equal response or sensitivity in the different color "channels" = layers (greens in B&W, reds and blue in tranies or color negs, all that was such a headache).
    With digital you can "easily" correct such responsiveness of the sensor by creating your own camera profile. But in any case, it is better to use a lighting system which is not giving such problems, being it for film or for digital mediums. There are many brands giving close to perfect light.

    Quote Originally Posted by SergeiR View Post
    Granted - i have never ever taken electronic parts apart. And i don't have latest backs, which might have some cool new features.
    But i would much rather trust my flash meter and not waste shutter counts / batteries with camera, making scene ready before subject arrives on the set, than having to deal with whole thing on the fly. Plus, having light exactly where i want it and not "oh its within one stop, i will later fix it" - is much better. Not to mention that whole "i will later fix it" never truly yields good results as good.
    You misunderstood what I meant when saying the histogram is the best possible light-meter: it is not meant to say that one has then the possibility to "repair" or fix light afterwards when it is within +/- x f stops. It is exactly the contrary, to let you set the light in the subjects, based on your decision (e.g. get that particular shadows part at - x under-exposure, the 1/4 tones at - y, the mid-tones at ..., the 3/4 tones at +..., the highlights at + ..., the first shadows with details at - ..., the last high-lights with details at + ...). You are absolutely free, but obviously this by changing the light in your subject, not by tweaking the file afterwards with the software (though this is still possible to a certain amount, more so with MF digital files, and better so when the exposure is perfect).
    That was what I meant, and in the contrary, this method allows to get better files with less needed tweaks afterwards.

    Actually, I was running "Black & White - Zone Systems" workshops, at a time were digital was at its beginning: we (me and the participants) would have loved to be able to use such a light-meter to get the correct exposure/zones in our subject.
    And in addition to all this, the histogram light-metering allows to measure the light exactly where it falls, on the image plane (TTL light-metering), with no headaches because of exposure compensations to be used (filters, bellows extension/magnification, etc ...).

    Quote Originally Posted by SergeiR View Post
    Or if you meant what i meant by main tone? Its just a whole zone thing. Shooting black cat on the snow, shooting white cat on black paper, shooting gray cat on gray paper... That kind of stuff. Having to remember to compensate and do whole zone placing b/c of reflected metering for histogram is not much of a picnic either (not like there is much choice for landscape of course, but at least for portraits there is)

    Just me. I learned to not trust histograms much, walking softly and carry around big stick once again..
    See my explanations above, Sergei. It is exactly that, the point: zone system metering. A white cat on a white background, or a black panther in a tunnel entry, or in the snow, no matter what, the zone system allows you to set the light exactly to be able to distinguish details where you want them to be. And for this the histogram is the best tool.
    Believe me, I have used all types of light-meters, mainly Minoltas, for nearly 20 years, I and the vast majority of the photographers I have met found the histogram to be a "gift from God".
    Thierry Hagenauer
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    Re: Exposure problems

    Its too hard to do quotes on ipad, so i just will type in order.

    - you do not really have control to fine level of getting same response as in raw data , without extensive tweaking of everything, and then having to explain to people how the hell images are bleak and odd when displayed at first. Plus it requires me as photographer to deal with each lens and camera combo individually. Add iso into that. Doing this on the fly is painful. Yes, i can load some backs with profiles. Notice how i am keep saying that for some it might work. But not all people use latest and greatest
    - adjusting channel sensitivity on bayers sensor is hell of all diseases. If we had foveon structure, or true b&w - yes. Would be possible. But normalizing space when you got to interpolate from rggb or any other weird pattern in sensor array will get you. And nope, raw with strong color shifts is not recoverable in full ( extreme example is shooting one end of k scale, while white balance is set to same end), which is another practical proof of fact that if you got sensor with finite number of states, and offsetting it beyound capacity - register overflow is inevitable and information loss is right there.

    I am not arguing about usability of zone system ( not fan of it either, though) or histogram as extra walking stick. But i have found that life is way easier when i have lights (or scene) done with flash meter ( or worked with same light system long enough so you can wild guess exposure within 1/3-2/3 ev). I do have enough issues with controlling people within scene, to run around and keep adjusting lights while subjects holding poses but its me.

    Calibrated flashmeter i am talking about, like 758dr. Not any.

    And its not about film film is whole other subject, imho.

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    Re: Exposure problems

    I always find these conversations funny. Member X says I do this and it works for me, and a whole bunch of members come on and say you should not do that because we do it a different way and our way is better. Which begs the question, better for whom? And then when you look at Sergei's work, it is kind of hard to criticize his method.

  38. #38
    Senior Member Thierry's Avatar
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    Re: Exposure problems

    It was never meant as a criticism of the method used, nor is it my intention to force into anything, but it is rather an open discussion between photographers in which one tries to give and exchange information, the way this forum works and should be for.

    My apology if you felt so, Sergei.

    Best regards
    Thierry

    Quote Originally Posted by Shashin View Post
    I always find these conversations funny. Member X says I do this and it works for me, and a whole bunch of members come on and say you should not do that because we do it a different way and our way is better. Which begs the question, better for whom? And then when you look at Sergei's work, it is kind of hard to criticize his method.
    Last edited by Thierry; 21st December 2011 at 07:30.
    Thierry Hagenauer
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  39. #39
    Paul66
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    Re: Exposure problems

    I'm kinda enjoying the discussion since I see it as we are al still learning no matter how advanced one is.

  40. #40
    jeffacme
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    Re: Exposure problems

    Quote Originally Posted by Paul66 View Post
    I tried a friends light meter and it's dead on, not sure what happened with mine but I guess electronics just fail.
    Thanks for all the advise and thanks for not bashing my ignorance for tech terms, I am self taught and learned trial and error
    Paul,

    So much of the old school theory is vanishing. Developing a Mental/Experiential warning system is key to consistent results and spotting trouble before it affects the outcome of a shoot.

    In pure strobe situations it all comes down to simple math. Output level A+distance B=f8 Changing the output setting from 6.0 to 7.0 or moving the light from 5.6' to 4'=f11. The reason many Graybeard film shooters never use flash meters is this understanding of how output and distance relate to exposure. This warning system also would have told you that something was up either with your meter or strobe output. Metering several lights could have eliminated the output as the culprit and called into question the accuracy of the meter.

    While distance to subject affects output Johnny is correct in pointing out it also affects the quality of the light on the subject and should be considered.

    As many have said the histogram is king but I would go a step further and say that it is always used to confirm what your M/E warning system is already telling you.

    If you want total control over of every pixel it is important to become an accomplished practitioner of curves. Any cast can be removed and perfect, at least to your liking, color balance and contrast will always be in your control. Read everything you can by Dan Margulis and experiment with CMYK retouching especially for skin tones. It is easy once you have the chops to balance any skin tone when you can break the red channel down to it's component parts Y and M.

  41. #41
    Senior Member Stefan Steib's Avatar
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    Re: Exposure problems

    Paul
    as a User of Lightmeters for years also I think you simply run into the fact that about all MF Backs are a bit "cheating" on sensitivity. This was confirmed by DXO see here - depending on your back and compared to which camera this may be as much as 1,5 Stops.
    See the graph I downloaded from DXO.
    This is not really a problem most of the time when you just use Histograms -
    see Siebel (and as we all do this now!) and other comments :

    " I sold all my meters and have never looked back. Shoot a test frame, check the histogram and adjust from there. This is WAY faster and more accurate than any meter."

    It is accurate to achieve best results, but it is NOT accurate in terms of absolute Values.......

    Greetings from Munich
    Stefan
    because photography is more than technology - and " as we have done this all the time "
    facebook:hcam.de - www.hcam.de - www.hartblei.de

  42. #42
    Subscriber and Workshop Member MGrayson's Avatar
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    Re: Exposure problems

    I've often wondered what DxO were going on about, so I checked their website. They define ISO not relative to some fixed optical density, as there is no such thing on a sensor, but relative to total saturation. This has the odd effect of lowering the "measured ISO" when a sensor increases its headroom. Or equivalently, I could double the measured ISO of my sensor by clipping the signal when the sensor wells are half full.

    In that light, the often reproduced chart of manufacturers "cheating" shows, instead, manufacturers offering extended highlight retention.

    Matt

  43. #43
    Senior Member Stefan Steib's Avatar
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    Re: Exposure problems

    Hi Matt

    I think I know what you mean, if you take a look at tonal range and on the Signal to Noise level all 3 cameras are on par again.
    But the dynamic range shows the same discrepancy, which I cannot explain with your Theory !

    Regards
    Stefan
    because photography is more than technology - and " as we have done this all the time "
    facebook:hcam.de - www.hcam.de - www.hartblei.de

  44. #44
    Subscriber and Workshop Member MGrayson's Avatar
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    Re: Exposure problems

    I have no horse in this race, I'm just trying to understand what DxO's numbers mean. I suppose I should now look at how they define dynamic range, which depends on shadow noise, which can be measured per-pixel, per square mm, or per-image percentage. Each choice will favor a different sensor. You really can make these charts say (almost) whatever you want by a judicious choice of coordinates and definitions.

    On the other hand, I abhor the "I don't care what the numbers say, the Artist must rise above mere technology!" argument used whenever the measurements disagree with a cherished position. (See the laughable "6 stops better DR" thread from Lu-La). But I digress.

    Has the OP's issue been resolved? It certainly seemed like a flash sync problem and not an issue of manufacturers mislabeling ISOs or faulty light meters.

  45. #45
    jeffacme
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    Re: Exposure problems

    "Absolute Values" interesting but irrelevant to the process I am advocating.

    Having a thorough understanding of your system and how it behaves creates a device independent atmosphere that accounts for the variation described and puts the user in total control and aware of changes that affect the final result.

  46. #46
    Senior Member Stefan Steib's Avatar
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    Re: Exposure problems

    Matt @ all

    quite easy to find out. I´m sure Paul has "ANY" 35mm digital body that he can compare with what he gets from the back. If this shows normal exposure at the same settings and the same equipment...........

    Regards
    Stefan
    because photography is more than technology - and " as we have done this all the time "
    facebook:hcam.de - www.hcam.de - www.hartblei.de

  47. #47
    jeffacme
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    Re: Exposure problems

    Quote Originally Posted by Paul66 View Post
    Oh and this only happens when shooting with strobes
    As Paul stated earlier

  48. #48
    Super Duper
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    Re: Exposure problems

    The digital world has not changed the fact that a handheld meter is best when working systemically with your system. Shutter inefficiency, shutter error, lens transmission, actual ISO of your back, etc. will impact what your meter says and what the correct exposure is, although the shutter will have little affect in Paul's case.

  49. #49
    Senior Member johnnygoesdigital's Avatar
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    Re: Exposure problems

    All these charts are impressive, but I agree with Jeffacme, about having a through understanding of one's camera system. The fact that Paul states it's only with strobes, seems to indicate, that use of the inverse square law might be appropriate in this scenario. Or in other words...move the lights. Keep us posted, and perhaps take more photographs of the model to be sure

  50. #50
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    Re: Exposure problems

    re the histogram. this is really sort of an incident meter that happens to show where the highs and lows fall. Unlike a reflected meter reading, the histo does not relate the readings literally to specific parts of the scene. You can guess, but that is not the same thing. I find it useful in the same way my incident meter is useful

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