Incident or reflective....old school light meter....

[TooManyShots]

The light meters in digital cameras are designed for that cameras individual sensor not film , so I.S.O 100 on a digital camera isn't the same as 100 I.S.O on a hand held separate light meter and film which is why the readings don't agree, if you want to use a reflected/incidental hand held meter use film.

That maybe true but the thing is that I was using the light meter on my 30D to shoot my first roll. I didn't have a light meter with me that time. The shots turned out OK. "http://www.flickr.com/photos/vracing/sets/72157631785544025/" Removed the quotes. Yeah, another way to meter is to turn the meter facing the sun and take an incident reading. This obviously would require me to walk maybe 200 ft to get into an open area. This may or may not be possible in real life of course.

 

[wiltw]

The light meters in digital cameras are designed for that cameras individual sensor not film , so I.S.O 100 on a digital camera isn't the same as 100 I.S.O on a hand held separate light meter and film which is why the readings don't agree, if you want to use a reflected/incidental hand held meter use film.

OMG, this is a lot of misleading information. If it were true, why would my Minolta Spotmeter F give me identical readings as my Canon dSLR, when both are aimed at the same 18% grey card and set to the same ISO value?!?!?!

In fact, using my Minolta Autometer Vf in incident mode, its reading agrees with the two reflected light meters mentioned above, too.

And exposures are fully satisfactory if I am shooting with my medium format film color transparencies or my dSLR...I do not need to compensate one vs. the other, to deviate from the meter suggestion, which would be necessary if the digital ISO value were not the same as film ISO.

 

[TooManyShots]

OMG, this is a lot of misleading information. If it were true, why would my Minolta Spotmeter F give me identical readings as my Canon dSLR, when both are aimed at the same 18% grey card and set to the same ISO value?!?!?!

In fact, using my Minolta Autometer Vf in incident mode, its reading agrees with the two reflected light meters mentioned above, too.

Hahahaha....that's almost like saying each DSLR unit has its own metering standard and photographers can't cross reference with one body with another. I am pretty sure if you meter with an EOS 3 with a Canon 1dmarkIII on the same scene, you get the exact same reading.

 

[markbarendt]

What is different about metering for negatives and metering for digital is that digital ISO is determined by a resulting JPEG that comes from the standard ISO process for digital, essentially the "final result", much as for slide film.

The resultant JPEG is a result or the sensor and the manufacturers software, hence different for every camera. A DSLR can get you a reasonable exposure setting at a given ISO but it is far from being able to mimic a negative.

ISO for negative film is keyed to the negative's density at certain points. Negatives are an intermediate medium, while there is an ISO speed point film can, for example with XP2 a 400 speed film, be shot at 50,100,200,400, or 800 and create nearly equivalent prints, the "final result".

 

[baachitraka]

Your samples in flickr has survied from metering through digital camera because SBR is rather very short or short. In almost all examples, except the pot rest have shot with diffused light.

 

[TooManyShots]

What is different about metering for negatives and metering for digital is that digital ISO is determined by a resulting JPEG that comes from the standard ISO process for digital, essentially the "final result", much as for slide film.

The resultant JPEG is a result or the sensor and the manufacturers software, hence different for every camera. A DSLR can get you a reasonable exposure setting at a given ISO but it is far from being able to mimic a negative.

ISO for negative film is keyed to the negative's density at certain points. Negatives are an intermediate medium, while there is an ISO speed point film can, for example with XP2 a 400 speed film, be shot at 50,100,200,400, or 800 and create nearly equivalent prints, the "final result".

What if you shoot RAW????

 

[TooManyShots]

Your samples in flickr has survied from metering through digital camera because SBR is rather very short or short. In almost all examples, except the pot have diffused light.

The flower pots shot was not shot in diffused light. It was at night. Film speed was 400, f3.5, 1/50s shutter speed. There was a home depot utility light powering a 23w CFL. The lamp distance to the pots are about 1 foot above.

 

[baachitraka]

The flower pots shot was not shot in diffused light. It was at night. Film speed was 400, f3.5, 1/50s shutter speed. There was a home depot utility light powering a 23w CFL. The lamp distance to the pots are about 1 foot above.

Correction: I wanted to write, expect the flower pot shot rest was shot with diffused light.

 

[markbarendt]

What if you shoot RAW????

This ISO standard is the ISO standard, ask the ISO if you really want to know.

 

[benjiboy]

OMG, this is a lot of misleading information. If it were true, why would my Minolta Spotmeter F give me identical readings as my Canon dSLR, when both are aimed at the same 18% grey card and set to the same ISO value?!?!?!

In fact, using my Minolta Autometer Vf in incident mode, its reading agrees with the two reflected light meters mentioned above, too.

And exposures are fully satisfactory if I am shooting with my medium format film color transparencies or my dSLR...I do not need to compensate one vs. the other, to deviate from the meter suggestion, which would be necessary if the digital ISO value were not the same as film ISO.

I base my information on tests done by the technical staff of Professional Photographer Magazine with a Minolta Autometer VF done in an article in the last few years, this is also why you can programme the sensitivity of Sekonic L-758 Meters to the actual individual sensor of up to four different digital cameras, because they are all have different responses to light. Watch this , and you will understand.
http://www.youtube.com/watch?v=tdyosItw3Mk

 

[baachitraka]

This ISO standard is the ISO standard, ask the ISO if you really want to know.

Further standardised digital camera meter do not really care about the format, it just suggests a value(shutter speed and aperture).

 

[Diapositivo]

http://en.wikipedia.org/wiki/Film_speed (it also talks about digital camera ISO measurements).

Measuring ISO film speed depends from method chosen and some assumptions made in the ISO method.
Measuring of digital cameras' ISO sensitivity is even more complicated and up to a certain point arbitrary.
Digital ISO sensitivity when using raw is even more arbitrary or if I get it right impossible, just like it would be impossible to define the ISO sensitivity of a film without specifying the development method. The film with a latent image does not have an ISO rating per se.

Theory aside, I don't subscribe the idea that incident light metering cannot be used for digital cameras and the other way round. At most, one can find the deviation of the two (e.g. in the exact same conditions your DSLR 200 ISO is maybe equivalent to your reflected light meter 160 ISO, a third of stop off) and work from there obtaining reasonable values from a practical point of view. Over-thinking the matter doesn't help.

The rationale of bringing a DSLR instead of a separate light meter to help exposure with a film camera is certainly questionable, but that's another matter.

Separate light meters, and incident light metering in particular, are quite in use as far as I know also with digital cameras, not just with film cameras. E.g. in portrait work incident metering is used also when working with digital cameras, if I have to believe to videos I see on TV.

Modern separate light meters can be programmed with the dynamic range of the camera or film in use so as to better help exploiting the dynamic range without burning highlights (a problem with slide film and especially a problem with digital cameras because of the "cliff effect" or "wall effect" of the highlights).

The same separate light meters are employed also in digital photography which means the the ISO value makes some sense with both technologies (small correction factor apart if the manufacturer was a bit "optimistic" regarding ISO sensitivity for marketing reasons).

The ISO value of a digital camera is infinitely less useful an information than the ISO value of a film, and the logic in exposing a digital frame can be completely different than exposing a film frame (especially negative) so it's not so much the meaning of the ISO term in the two different technologies (which at the end of all the theory is in practice more or less the same) but the general exposure logic which can be completely different when the subject brightness range is extended.

Conclusion: a DSLR can be used as a light meter with a film camera if the subject brightness range does not pose problems, small repeatable differences apart. I wouldn't use it with complex light as the matrix metering might try to salvage highlights applying some sort of strategy which wouldn't fit film photography*.

YMMV

* I wouldn't use matrix metering in any case, but that's me.

 

[benjiboy]

Hahahaha....that's almost like saying each DSLR unit has its own metering standard and photographers can't cross reference with one body with another. I am pretty sure if you meter with an EOS 3 with a Canon 1dmarkIII on the same scene, you get the exact same reading.

That's exactly what I'm saying, because you are obviously new to photography before you start laughing, at facts your'e "pretty sure" about, watch this video and it will explain that individual DSLR sensors give different responses to light. and how some light meters can be calibrated to each cameras individual sensor http://www.youtube.com/watch?v=tdyosItw3Mk

 

[TooManyShots]

That's exactly what I'm saying, because you are obviously new to photography before you start laughing, at facts your'e "pretty sure" about, watch this video and it will explain that individual DSLR sensors give different responses to light. and how some light meters can be calibrated to each cameras individual sensor http://www.youtube.com/watch?v=tdyosItw3Mk

So, how many stops of light we are talking about here? If the difference has no meaning in a real world situation, I would rather focus on shooting. You can say I am new since I didn't start shooting during the film age.

 

[Alan Klein]

Originally Posted by Alan Klein(there was a url link here which no longer exists)I think you're the only person who picked up he's shooting digital on a film forum.
I shoot both... And doing paid gigs with digital of course.

I was just trying to get a laugh. My own experience using Minolta IIIa with both features, is to use
10% spot reflective when the shot is in the distance and once in a while to use incident if I'm in the same light as the subject and fairly close. The meter allow me to average three readings. I also braket 1 stop. Of course, I only use this method when shooting film. I wouldn't want anyone in the forum from getting upset.

 

[Poisson Du Jour]

I was just trying to get a laugh. My own experience using Minolta IIIa with both features, is to use
10% spot reflective when the shot is in the distance and once in a while to use incident if I'm in the same light as the subject and fairly close. The meter allow me to average three readings. I also braket 1 stop. Of course, I only use this method when shooting film. I wouldn't want anyone in the forum from getting upset.

A 10% spot-reflective? What is this referring to? I've only ever known 1% to 3% spot.

Reala can easily handle 3.5 stops under and over. I would not get all hot and bothered about manually metering it. Very, very different and critical story if you migrate to transparency.

IGNORE what a digital camera tells you; the metering technology does not permit accurate parallels with e.g. analogue (film) use. Worse still is people relying on the histogram as an indicator of brightness range. Chuck it out, all of it, and learn metering basics first.

 

[Alan Klein]

Sorry I meant 10 degree. Here's link to it. You screw off the white incident adapter and screw on the 10 degree reflective attachment. You can also get a 5 degree attachment.

http://www.ebay.com/itm/Minolta-Aut...252399?pt=US_Light_Meters&hash=item2c65f7142f

 

[wiltw]

I base my information on tests done by the technical staff of Professional Photographer Magazine with a Minolta Autometer VF done in an article in the last few years, this is also why you can programme the sensitivity of Sekonic L-758 Meters to the actual individual sensor of up to four different digital cameras, because they are all have different responses to light. Watch this , and you will understand.
http://www.youtube.com/watch?v=tdyosItw3Mk

Consider also this fact...I happen to have three brands of film cameras, and I get different readings from the meters of each of them pointed at the same 18% grey card. So which would you believe when loaded with a so-called ISO 100 film?! The same issue happens with dSLRs, too. Thge same happens with light meters, too.

We know that the ISO standard equations for incident meters and for reflected meters both have VARIABLE value 'constants', where the manufacturer of the camera/meter gets to choose the value that they use!

 

[Poisson Du Jour]

Consider also this fact...I happen to have three brands of film cameras, and I get different readings from the meters of each of them pointed at the same 18% grey card.[...]

And why does that happen?

 

[benjiboy]

So, how many stops of light we are talking about here? If the difference has no meaning in a real world situation, I would rather focus on shooting. You can say I am new since I didn't start shooting during the film age.

To members of this forum we are still "in the film age". I don't know how many stops because each sensor has it's own response as I explained, and since your question is basically about digital cameras I think Your querys would be better addressed to our sister site DPUG http://www.dpug.org/forums/f38/

 

[benjiboy]

Consider also this fact...I happen to have three brands of film cameras, and I get different readings from the meters of each of them pointed at the same 18% grey card. So which would you believe when loaded with a so-called ISO 100 film?! The same issue happens with dSLRs, too. Thge same happens with light meters, too.

We know that the ISO standard equations for incident meters and for reflected meters both have VARIABLE value 'constants', where the manufacturer of the camera/meter gets to choose the value that they use!

I basically agree with you from my experience, but since different makes of cameras exposure systems have different parameters in their design it's quite possible to to have some small deviation in their responses when pointed at a Grey Card, I have noticed this myself in my cameras, but I don't find this in practice significant because in isolation each camera gives me correct exposure, and comparing light meter and thermometer readings I find is a very quick way to drive yourself crazy

 

[wiltw]

And why does that happen?

Read about this here (it would have been handy to have this summary available --which it wasn't -- 25 years ago, when I first learned about the issue from Ctein!)
http://en.wikipedia.org/wiki/Light_meter

"Determination of calibration constants has been largely subjective; ISO 2720:1974 states that

"The constants K (in reflected meter calibration equation) and C (in incident meter calibration equation) shall be chosen by statistical analysis of the results of a large number of tests carried out to determine the acceptability to a large number of observers, of a number of photographs, for which the exposure was known, obtained under various conditions of subject manner and over a range of luminances."

Since each meter manufacturer gets to CHOOSE the actual value of the constant, the fact that meters do not agree with each other is inherent to the ISO calibration standard equation in the Wikipedia article! And the wording of the above paragraph in the ISO standard will allow you to see that exposure meters offer a GUIDE TO EXPOSURE.

 

[wiltw]

I basically agree with you from my experience, but since different makes of cameras exposure systems have different parameters in their design it's quite possible to to have some small deviation in their responses when pointed at a Grey Card, I have noticed this myself in my cameras, but I don't find this in practice significant because in isolation each camera gives me correct exposure, and comparing light meter and thermometer readings I find is a very quick way to drive yourself crazy

And many of us know, from the routine use of EI 40 to expose Velvia which was rated ISO 50, that even the ISO ratings of film are rather arbitrary! So why would we be surprised to see some variability in ISO sensitivity within digital cameras, too?!

This brings us back to why I originally objected to your commentary in post 23, "so I.S.O 100 on a digital camera isn't the same as 100 I.S.O on a hand held separate light meter and film which is why the readings don't agree".

My digital camera meter matches my traditional handheld ('for film') meter! And my film camera meters don't all agree with each other, so they provide a shakey reference standard by which to judge digital camera meters, and film itself is not necessarily a perfect standard either, so film is an imperfect standard to compare against digital sensor sensitivity!

 

[E. von Hoegh]

IGNORE what a digital camera tells you; the metering technology does not permit accurate parallels with e.g. analogue (film) use. Worse still is people relying on the histogram as an indicator of brightness range. Chuck it out, all of it, and learn metering basics first.

Best advice so far.

 

[markbarendt]

And many of us know, from the routine use of EI 40 to expose Velvia which was rated ISO 50, that even the ISO ratings of film are rather arbitrary!

We need to be careful not to confuse ISO and EI.

You and and your buddies may like Velvia at an EI of 40 but that doesn't mean the film has an ISO rating of 40.

ISO ratings are determined by where a specific density falls on the film curve in a lab under highly controlled conditions, it has nothing to do with where you or I like our exposures to fall on Velvia or any other film.

ISO film ratings are very reliable and quite standard in practice. The wild cards that affect our perception of ratings are typically related to "our" problems.

Meters, like thermometers and other gauges, need maintenance calibration to stay accurate. If I chose to get all my camera meters calibrated as well as my hand held, then they too would all agree.

My developing regime cannot match the quality control of Fuji or Ilford.

My shutters work well and are close, but perfect, no.

My sensibility bout what a shot should look like is different than yours.

EI factors in all these variables, ISO does not.