18% Grey Card. To use it or not.

Bill Burk said:

Camera exposure profiling is “interesting” but I chose to set clipping points on whole stops and call it Zone System calibration. Meaning instead of fitting camera to meter, I was fitting meter to Zone System.

I left the constants at factory defaults.

Click to expand...

Profiling with the L758D/DR is more generally useful for digital cameras than analogue. But there is a handy trick!

In lieu of the profiling function's original purpose, camera profiling is in my case used to switch between separately set metering metrics for the Pentax 67 (camera profile 1) and pinhole photography (camera profile 2).

Alan Edward Klein said:

Your process does not work in this case. If you're shooting color chrome film, you want to shoot based on the exposure in the bright sunny light. If you pick a middleground between light and shadow, you;ll blow out the whites in the sunny areas. With chromes you pretty much ignore the shadow areas.

Click to expand...

Not a problem for me -- I gave up chromes when they killed Kodacrome 25 & Cibachrome.

Taylor K Nankervis said:

There is no trick, no rocket science, no mystery. The lumisphere and spot meter both have their critical applied uses. Neither is superior to the other in each and every application. With a spot meter (1° in the case of the Sekonic L758D/DRs)

• Meter a bright section of the scene, but not a bright spectral.
• Meter a transitional scene between bright and dark; and
• Meter a shadowed area, but not completely black
Areas that require special consideration by the meter can be double-tapped;
• Average all.

Simple way is to use a grey card, locked in as reference reading No. 1, then all the other readings and
averaged — very quick and efficient. Spot/incident/mixed metering is critical to a good exposure (but every photographer will have his/her own preference of what constitutes a 'good exposure' in their experience), but the process of metering should not be over-complicated!

Click to expand...

This is pretty much what Paul Farber outlined in Petersen's Photographic back in the 70's -- i.e. May, 1978 -- The Two-Zone System. You meter the high and the low, as you described, and compute a contrast index (C.I.) from the difference between them -- (HIGH EV - LOW EV) / 0.3. Then you can look up in the Kodak charts for how to develop that specific film and C.I..

But, as he points out, this is best used with sheet film, but can be helpful sometimes with roll film too.

I've used a variety of spot-meters all the way from the Pentax 1/21 analogue up to the Sekonic L758D digital and I've always carried an 18% grey card BUT I don't use the card for light-metering.

The card becomes a fixed visual reference for judging the tones of things. I place the card on rocks, tree bark, dirt, dry grass, concrete, and so on, in an attempt to develop a mental catalogue of
the visual world in terms of what's the same, what's darker, what's brighter, and by how much.

It is a great power of spot-meter use within the Zone System that any tone can be placed on any Zone. This is the "place" and "fall" technique; place one zone and see where the others fall.
My worry was to do the initial placing in a credible way. And knowing the inherent brightness and darkness of things helped me get the place correct with some confidence the fall would make sense too.

Maris said:

The card becomes a fixed visual reference for judging the tones of things. I place the card on rocks, tree bark, dirt, dry grass, concrete,

Click to expand...

Sounds like well-travelled, domesticated grey card then!

Maris said:

The card becomes a fixed visual reference for judging the tones of things. I place the card on rocks, tree bark, dirt, dry grass, concrete, and so on, in an attempt to develop a mental catalogue of
the visual world in terms of what's the same, what's darker, what's brighter, and by how much.

Click to expand...

I too mostly use the gray card as a visual reference for 'middle tone' of surrounding objects, rather than as a meteing target. But just as the gray card makes a variable density due to surface reflectance while metering, that variabillity of apparent desnty can manifest itself as a variable tonal reference! One needs to keep both in mind whenever a gray card is employed.
This illustrates both the variable tonal reference as well as variable metering target!



At the same time, an incident light meter's angle to the sun position, and angle relative to vertical both make a difference

IOW one needs to understand that foibles of BOTH the gray card target and the incident light meter hemisphere in order to optimize the use of each.

Taylor K Nankervis said:

There is no trick, no rocket science, no mystery. The lumisphere and spot meter both have their critical applied uses. Neither is superior to the other in each and every application. With a spot meter (1° in the case of the Sekonic L758D/DRs)

• Meter a bright section of the scene, but not a bright spectral.
• Meter a transitional scene between bright and dark; and
• Meter a shadowed area, but not completely black
Areas that require special consideration by the meter can be double-tapped;
• Average all.

Simple way is to use a grey card, locked in as reference reading No. 1, then all the other readings and
averaged — very quick and efficient. Spot/incident/mixed metering is critical to a good exposure (but every photographer will have his/her own preference of what constitutes a 'good exposure' in their experience), but the process of metering should not be over-complicated!

Click to expand...

Yes, trick is not the word. But incident meter the shadow facing the camera and -1 stop to the exposure.