Light meters, analog vs. digital...

[Lance Lucero]

Anyone still using an analog light meter for film?  To be clear, REAL FILM, not HD.  I have a digital  Sekonic Flashmate L-308X-U that I have been using and it keeps telling me to open the camera up more than I need to...  I just bought an analog  Sekonic L28c2 and I'm getting reading that I believe to be more accurate...  I mean, the difference between the two meters can be up to a 2 stop difference, with the digital meter always pushing an over exposed image.  I even sent  the digital back to Sekonic for calibration and I'm getting the same readings...  Do the digital meters today understand film?  Any opinions on this?

[Andrew Schroeder]

I've had very similar issues even when trying to meter for digital cameras, always overexposing and washing out color. My partner and I have a start up that deals with modifying digital cinema cameras for better color and as part of it, due to this issue, we ended up studying the history of measuring light. Long story short, there was never a true universally agreed upon set of standards, and the methods for how film sensitivity is measured changed a few times over the years. A surprising amount of current light meters use calculations that incorrectly account for these changes. For these and other reasons we ended up creating our own light meters, which use analog hardware.

[Ruben Arce]

It is true that there is not a defined standard being used, but they should not be that far apart.  Digital cameras use ISO which is a standard, but then they do all kind of tricky things with their RAW or LOG formats to make their cameras look good or more sensitive than they actually are. Now Kodak uses ISO instead of ASA which is basically the same.

There have been two standards used for light meters through history but the results are pretty close. Ansel Adams was a proponent of the 18% gray standard, and manufacturers prefer 13% gray because it delivers brighter images. In "The Negative" Ansel Adam's book from the 70s he talks about the K factor, which is a compensation of about half stop from 18% gray and that is exactly the difference between the two standards. I have tested several hand held and camera meters and they work properly. They are half stop off from each other. Sekonic and modern cameras use 13% gray, but they don't disclaim that information because it is very confusing for some people so they simply don't disclose that information.

If your old meter works properly, it should give you numbers no more than half stop off of the Sekonic, but let me tell you that I was there a few years ago telling myself that the meters don't work properly, that they were not designed to work with digital cameras and stuff like that. It took me a long time to learn how to get proper readings and I was the one thinking my meter needed to be calibrated and that it was not accurate at all or that I needed an expensive one. When I learned how to use it properly it started working for me right on the spot every single time.

You should test your meters in a simple setup. Put the two meters next to each other under the sun in exactly the same conditions, using exacly the same settings, or in a studio with even light and they should give you close readings. Some old meters specially the ones that don't have batteries don't work properly anymore and some meters that require mercury batteries don't give you accurate readings because those batteries don't exist anymore in this part of the world and replacements don't put out the same amount of power.
 

Another simple way to test your meters is using the Sunny 16 rule. Do your research.

I use my Sekonic L-558 Cine to shoot all kinds of film motion and stills and the images are right on the spot every single time. There is nothing special about film, light meters work just fine and they do work with good quality DSLRs as well like my D810 or the D850 or cameras in that range. With Digital Cinema cameras you can always calculate the ISO they are using and once you find it you can use your meter with the camera, but I can tell you that with LOG formats they pretty much do whatever they want.