m240 meter off?

[jbl]

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Let me preface this by saying that I don’t think what I’m describing is user error. I’ve done a medium amount of sensiometry with film scans, I wouldn’t say I’m an expert at all, but I would say I think I know what I’m doing.

 

With my M240 (normal mode, no live view), I’ve been noticing that when I base exposure on experience, I’m almost always under exposing (according to the internal meter as well as based on what the output file looks like). I’ve also noticed that when taking photos of my (Caucasian) daughter, if I expose up by a stop, I almost always way over-expose.

 

Today I got the grey card out to check this. I took an incident and a reflected metering which agreed within a tenth of a stop: f/4 @ 1/90s @ ISO 640. I shot the grey card and brought the DNG into Lightroom. I checked the luminance on the middle-grey reading and it was around 25% which is way too low. I boosted exposure in LR by 1 full stop which got me to around 45% luminance which is a “correct” value according to Ralph Lambrecht’s book. This value more or less matches my experience with the camera, I seem to be off by one stop.

 

I’ve checked exposure compensation and that’s disabled.

 

Has anyone seen anything like this? I wouldn’t discount the possibility of user error, but my sensiometric readings do seem to match my experience with the camera.

 

-jbl

[Hookeye]

Interesting. This seems more or less like the same problem I raised a year back.

 

http://www.l-camera-forum.com/leica-forum/leica-m-type-240/296163-m240-light-meter-oddity.html

 

Regards HP

[jbl]

That sounds exactly like what we’re both seeing.

 

Guess the digital age is more like the film age than I thought :-).

 

Have you tried a Zone I test?

 

Have you just been coping with it and setting external meters to a lower ISO than the camera?

 

-jbl

[Hookeye]

I just set my external meters to EV-1 and and live with it. It is very odd, but no problem once you are aware of it.

 

As to the Zone I test I am ashamed to admit I don't know what it is

[tonemeister]

I have found a similar thing with my M240 - have to open up an extra stop compared to M8/M9.

 

Cheers,

T

[jbl]

Oh. In b&w film, you'd have to figure out what your effective film speed was based on a film, developer and development time combination. You basically meter a grey card, under expose 5 stops or more and then start taking shots opening up half a stop each time. You look for the first time you see anything above "film base plus fog." That's effectively Zone I which is four stops under middle grey.

 

When I was shooting 400 speed Tri-X, my effective speed was 320.

[Hookeye]

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Thanks jbl,

I must confess I chose the easy way out. If in doubt I would send my M6 to the local workshop to have it calibrated. And I shot mostly slides, Kodachrome. Those were the days...

[jbl]

I miss K64 a lot. And I've never found a digital filter that makes a camera look like it did. The VSCO stuff is pretty good (I never use it on Leica images, just to make my X100s and 5D3 look decent), but they don't have K64, I'd assume since they never were able to profile it because it was already gone .

[tonemeister]

Try Alien Skin's Exposure series. They have K64 profiled and several variants of it (from the 60s/70s etc.

[chris_tribble]

Hmm - I suppose you're metering for highlight areas (rather than the film practice of shooting for shadows...). I find that in Classic metering, that my usual practice gives very good results (often in difficult light) - i.e. mostly work with Manual exposure, and choose the critically illuminated area to meter against before framing. Works for me...

[jbl]

I'm talking about metering 18% gray cards here.

 

Exposing based on experience was from basing exposure on typical exposure charts.

 

In fact, in the exact same gray card scene, the MM was much closer totally out of camera than the M240.

[chris_tribble]

I'm talking about metering 18% gray cards here.

 

Exposing based on experience was from basing exposure on typical exposure charts.

 

In fact, in the exact same gray card scene, the MM was much closer totally out of camera than the M240.

 

But are you using auto or manual? I find manual works best for me...

[jaapv]

Digital "ISO" is a bit of a moving target. Whereas film ISO (by the norm sheet) is defined by densitometric measurements, the sensitivity of a sensor is obtained by comparison to film.

 

This leaves quite a bit of leeway for digital camera makers to interpret the ISO value.

 

In the beginning with the M8 we got quite a few threads noting that there was a significant difference between Leica and Canon. Consensus was that ISO 160 on the M8 (and later M9/MM) should be regarded as ISO 200, both in relationship with Canon and external meters.

It appears that Leica has adjusted the values to be in line with the industry average on the M240.

 

So bear in mind that with a digital camera we are dealing with an approximation. If it does not match your expectations, dial in a permanent compensation.

This btw is no different from film cameras. One always had to adjust the metering to the idiosyncrasies of the camera/meter and to the personal preferences for developing.

[jip]

I've noticed this as well, If I shoot a image with the M240 at ISO 200 the same speeds as my R8 reads with a similar lens on the same stop the image from the R8 is exposed correct, and the M240 image is underexposed. This was with the DM-R.

[Fgcm]

+1

In sunlight I compensate a little or I correct later in PP.

It's a minor problem (if a problem at all).

Franco

[jbl]

I can work with this and as Jaap says this isn't really different from film. Glad to know it's not just me.

[paulsydaus]

I don't really 100% understand what you are saying because I'm not an expert.

But given Leica users are far more likely to move between film and digital, and also use external light metering, wouldn't it be better to seek consistency to that rather than another brand's digital camera be more beneficial? There is an agreed consensus that the M240 ISO values are off by a stop, and in a way that makes the camera appear to be more light sensitive than it is.

I'm not usually the one to speculate, but could it be there is more going on to this story than meets the eye (no pun intended)? As we all know, the race to sell more camera's is very much focused on ISO these days, and also the M240 had to of course advertise a significant ISO advantage over the M9... As has been said, dialling a filter factor or otherwise into your light meter will do the trick, but this isn't mentioned anywhere in the manual...

 

Digital "ISO" is a bit of a moving target. Whereas film ISO (by the norm sheet) is defined by densitometric measurements, the sensitivity of a sensor is obtained by comparison to film.

 

This leaves quite a bit of leeway for digital camera makers to interpret the ISO value.

 

In the beginning with the M8 we got quite a few threads noting that there was a significant difference between Leica and Canon. Consensus was that ISO 160 on the M8 (and later M9/MM) should be regarded as ISO 200, both in relationship with Canon and external meters.

It appears that Leica has adjusted the values to be in line with the industry average on the M240.

 

So bear in mind that with a digital camera we are dealing with an approximation. If it does not match your expectations, dial in a permanent compensation.

This btw is no different from film cameras. One always had to adjust the metering to the idiosyncrasies of the camera/meter and to the personal preferences for developing.

[rsolomon]

i'm new to the m 240 and noticing this. Its confusing (outside of marketing reasons) to understand why this was deployed. i appreciate the expert insight provided here. i continue my testing by bracketing with at a full stop 1 or (maybe ,7) over exposure

[FlashGordonPhotography]

There's a lot going on here but essentially the meter is trying to protect the highlights.  Digital doesn't roll of nicely like negative film.  It falls off a cliff and that just looks nasty.  Lots of digital camera do this. 

 

Secondly,  the zone system is of somewhat limited use with digital sensors.  It'. more linear than film so 18% may or may not be mid grey on a digital sensor. You're also not working with only 10 stops,  like you would if you processed to the zone system. 

 

Lastly you're importing DNGs into Light room.  Lightroom's natural curve is very flat and the program specifically goes to preserving highlights.  You could try using a different response curve when importing. 

 

Digital requires a re evaluation of how to expose.  The only reliable way is to use the histogram in the camera to make exposure evaluations.  Just remember the histogram response depends on the jet settings you have in camera. 

 

Gordon

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Hallo,

Look here: Leica M

[thrid]

I miss K64 a lot. And I've never found a digital filter that makes a camera look like it did. The VSCO stuff is pretty good (I never use it on Leica images, just to make my X100s and 5D3 look decent), but they don't have K64, I'd assume since they never were able to profile it because it was already gone .

 

Same here. I really miss Kodachrome... it was magical and nothing else looks quite like it.

 

Oh, I have noticed the same as you about the metering system. I've set my Sekonic to compensate, but as Jaap said, a test shot and checking the histogram really is the best way to go. I really would like to see Leica ad RAW metering like the Monochrom has to the general line up. 

 

For what its worth I've started to memorize certain common exposure settings like for daylight, bright / shadow side of street, city at night etc. At least this gives me a quick starting point.