Reflective vs Incident Exposure Metering Examples

[xpatUSA]

Recently received a Gossen Starlite 2 light-meter. Amongst it's many functions, it can do Zone measurement a la Adams/Archer - which re-kindled my interest in that. Armed with the strange phrase "place in Zone such-and-such", I went outside and used the camera spot-meter to "place" a white van's hood into Zones V, VI and VII.

I took the Sekonic L-398 along also and shot per it's incident-light recommendation with no compensation.



At top left, we see illustrated the reflective-metering adage, the one about mid-gray.

At top right, +1 EV comp, i.e. placed in Zone VI gave quite a good exposure. At bottom left, placing in Zone VII blew some significant highlights.

At bottom right, the Sekonic provided the best "placement" betwixt Zones VI and VII.

The shots are statistically insignificant because I couldn't be bothered to take hundreds of shots and I don't have hundreds of light-meters either ...

... but the simple test seems to bear out the literature. Hopefully it is of passing interest to some folks here.

Meanwhile, I'll stick with my current methods and I'm not looking for advice on how to expose a shot - thanks anyway ...

[Manfred M]

Very interesting Ted.

That being said, I have yet to see a convincing argument for the Zone System as applied to the digital age. The system definitely had applicability to the B&W darkroom back in the 1930s when the films had a lower dynamic range than what can be achieved with a digital camera and the printing papers had a very limited contrast range.

[William W]

IF . . . one is nutty enough to capture JPEG (in MONOTONE, B&W) with the intention of displaying / viewing the JPEG image SOOC. . . AND the contrast of the viewing screen is a known and constant: then, I have found that the "Zone System" (or my facsimile thereof) has a reasonable application.

I think it is certainly a "backwards application" to use the Zone System nowadays.

The Zone System is a procedure which had great merit both as a procedure and also as it being a big stepping stone and base to the procedures which are now best practice: but of itself today it remains simply fun for some - as much fun as Calligraphy or Philately, both seemingly useless practically, but still fun, for some.

Your experiment is of more than simple passing interest to me, thanks; the results add to my dabblings, which have reaped very similar results.

WW

[xpatUSA]

Thanks, Gents and a happy New Year/Decade!

The well-respected Jim Kasson has little good to say about the System as it applies to digital work.

Part 1: https://blog.kasson.com/the-last-wor...gital-cameras/
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[DanK]

I started photography back in 1968, so the zone system was something I studied a bit, and after I switched to digital, I read a number of pieces about the application of the system to digital. I concluded that it is entirely irrelevant to the capture. You get to control exactly one number when you set exposure. Assuming that the dynamic range of the image doesn't exceed that of the sensor, the best option is simply ETTR, which gets you the highest possible ratio of signal to noise. If that makes tones on average too light in a given image, you can simply adjust in post.

The more complex issue is trying to get the full range of tones to be distinguishable in the final image. That can't be addressed by metering. It has to be handled by postprocessing, and it is medium-dependent. One of the ways in which coated papers differ, for example, is by the range of dark tones they can replicate.

So, all that remains of the zone system in my workflow is spot metering. For example, I will often meter off the brightest area I don't want blown out and then adjust the exposure reading to place that area back to the right, where it belongs. To do this well, you have to have an idea of roughly how many stops incorrect the original reading will be, but one of the beauties of digital is that you can simply try, look at the histogram, and try again.

[Manfred M]

Thanks for the link. The assumption on the response curve of film has long been considered the weakness of the Zone System and I remember the arguments being made even in the B&W film days.

Again, back at the time, different films had different sensitivity curves which were both film and developer specific. I remember the data sheets that Kodak put out generally assumed that the film was being developed in their standard D-76 developer and Agfa assumed Rodinal was being used. I frequently used Kodak's Microdol-X fine grain developer which also had a fairly minor impact on the effected ASA/DIN rating; some people would overexpose by at least 1/3 stop when using that developer to compensate.

The other issue was use of fast and slow shutter speed, where reciprocity failure impacted exposure as one got into the non-linear response areas of the film. Again, this varied by film, but anything over 1/500th sec and below around 1/30th sec (again depending on the film and developer); the Zone System started to fail.

I do remember some people that studied photography at the college level were introduced to densitometers and got quite familiar with the actual response of their specific films using different shutter speeds and developers. Much more accurate than anything that the Zone System suggested...

[rpcrowe]

I have not done any comparison but, have lately been quite happy with the exposure on my white dogs from my Sony cameras using the HIGHLIGHT metering mode. I will normally use the multi metering mode for other types of photography.
Sony explains the highlight metering mode with this which really doesn't tell me a lot, "Measures the brightness while emphasizing the highlighted area on the screen. This mode is suitable for shooting the subject while avoiding overexposure."

Mark Galer's video explains a little more about Highlight Metering https://www.youtube.com/watch?v=9pV7zX0qC7Q
Highlight metering starts at 27.30 of the video...

Of course, I was getting perfectly acceptable exposures of these dogs before I ever used Highlight Metering. However, this metering system makes it a bit easier...

Since I shoot dogs so often, I have my cameras set up so that the settings for dog portraiture are on Memory One. If the dog is not white or very light color, I simply use the Fn menu to change the metering mode... BTW: Memory Two is set up for action shooting...

[xpatUSA]

I have not done any comparison but, have lately been quite happy with the exposure on my white dogs from my Sony cameras using the HIGHLIGHT metering mode.

Sony explains the highlight metering mode with this which really doesn't tell me a lot, "Measures the brightness while emphasizing the highlighted area on the screen. This mode is suitable for shooting the subject while avoiding overexposure."

As clear as mud ...

Mark Galer's video explains a little more about Highlight Metering https://www.youtube.com/watch?v=9pV7zX0qC7Q
Highlight metering starts at 27.30 of the video...

Thanks for the link. It sounds the same as if someone had spot-metered all over the entire scene and then exposed for the brightest object. He does mention that all other tones are slid downward as a result. A sort of auto-peak-brightness exposure option.

[DanK]

This may be a tangent, but...

In discussions like this, reflective metering is often portrayed as a weak surrogate for incident-light metering. Perhaps this is because I have been relying on reflective metering for half a century, but I don't buy it. The common view is probably reasonable for some types of photography, but it isn't true of the photography I do. My concern is the reflected light. That's what I am capturing. Reflective metering does a better job of telling me if there are blown highlights, for example, and allows me to compare the brightness of specific parts of the intended image. The latter is one reason I use spot metering so often. In situations where the dynamic range is such that I don't need to worry about those details, simple averaging, evaluative metering, or spot metering off a known surface (I sometimes use the old palm-of-the hand trick) work just fine most of the time. The bottom line for me is that I would feel handicapped if I had to trade my flexible reflective meter for an incident-light meter.

[xpatUSA]

This may be a tangent, but...

In discussions like this, reflective metering is often portrayed as a weak surrogate for incident-light metering.<>

In photographic fora, it seems that many people rely solely on the more exotic forms of AE such as center-weighted average not to mention billion-segment evaluative, both of which can get things wrong. And just about every article on metering mentions that in-camera meters are dumb, as we know.

So, like yourself Dan, I usually use the in-camera spot-meter - but I do take the Sekonic L-398 along when I remember because I like the dial with it's easy-to-use circular sliderule-like scales.

[Manfred M]

In discussions like this, reflective metering is often portrayed as a weak surrogate for incident-light metering.

It depends on the type of photography. For studio work with flash, I would agree 100%, especially when using a multiple light setup. For landscape work, it is not usually an appropriate solution and for other types of photography, it is more of an open question.

I know studio photographers that shoot using trial & error versus using a light meter. That generally works for simple setups, but start throwing in hair lights, rim lights or background lights, the situation gets a lot trickier. Try to get the background to fade out, having an reflective light meter works well as it lets the photographer know what is happening with light drop off.

The reason reflective light meters are so effective is that most scenes are in fact pretty close to "neutral gray" when converted to B&W. That being said, if I shoot in snow, I generally expose a stop more (+1 exposure compensation, to start) versus what the reflective meter tells me and one stop less (-1 exposure compensation) for most night scenes.

Most of the work I do does not require spot metering, but when I do need this I use either the one that is built into my camera or the 1 degree head for my Sekonic L-358 (which also has a 30 degree reflected light head).

[rpcrowe]

I primarily used an incident light meter in two settings: when I was getting my exposure for 16mm motion pictures and when I was setting up multiple lights in a studio.

The advantage of using a reflective meter for motion pictures is that I was usually shooting at the same shutter speed and ISO value. My Spectra professional meter used disks inserted into the meter from which I could read my f/stop directly with no computation.

The advantage in setting up lights is that I could replace the globe on the meter with a disk and therefore measure the light that was falling on the subject directly from the light I was using. I used a Sekonic meter for flash exposures and my Spectra when I was using continuous lighting...

However my built-in reflective camera meter did quite well for other scenarios.

Using studio strobes with "accurate" modeling lights does a lot to negate the need for incident metering. I can pretty well eyeball the lighting ratios and adjust the lights accordingly. Then I will use the camera histogram to indicate the proper exposure.

However when shooting the first studio exposure, I don't start off in limbo. I have a fairly accurate idea of the exposure...

When I am using the same set of lights, I can pretty well guess the exposure before shooting so the histogram is seldom very far off the mark in the first shot!

As an example when photographing my dog portraits using a softbox and a bounced TTL flash, I manually expose using ISO 320 with f/8 at 1/60 second and have the flash set at TTL. I will occasionally tweak the exposure a bit depending on the color of the dog's coat but, I am usually pretty close in my first try...

It is even easier now with mirrorless in that I can see the exposure I made by looking through the EVF. That way incident light doesn't impact my view of that exposure. IMO. one of the best attributes of a mirrorless camera is the information that can be gleaned abut the image by viewing through the EVF.

Of course, when shooting with off camera flash in a relatively dark studio, you don't have the WYSIWYG view that you have when shooting with continuous lights. However, it i still easier to review images through the EVF than by viewing them on the LCD...

[William W]

In photographic fora, it seems that many people rely solely on the more exotic forms of AE such as center-weighted average not to mention billion-segment evaluative, both of which can get things wrong. And just about every article on metering mentions that in-camera meters are dumb, as we know.

So, like yourself Dan, I usually use the in-camera spot-meter - but I do take the Sekonic L-398 along when I remember because I like the dial with it's easy-to-use circular sliderule-like scales.

One of the repeat questions often asked on forums (fora) is "What metering do you use?" (CWA, Matrix, Spot etc) and another is, "What Camera Mode do you use?" (M, Av, Tv, P... etc).

I think that many folk don't understand that the choices that THEY make as answers to these questions, are all related, and form their "Technical Procedure".

The main point of this comment is that it is a technical system which is required, and each part of that system has its own job, and is dependent upon each other part and MOST importantly it all must make sense to that particular Photographer and achieves the outcomes required.

I also use Spot Metering, often, not exclusively, but often, (especially I used to for Wedding Portraiture during the day's events, metering from Bridal Gown OR Bride's Face): - AND - that spot metering is/was used in conjunction with what we are discussing in another conversation [HERE LINK] Ref Post #18 - concerning Colour of metered subject and Density of that Colour) - but I'd typically use EVALUATIVE (Nikon = Matrix) Metering for Scenes, especially when I am travelling - AND - in this case I will typically BRACKET ±⅔Stop.

In both situations I will use M Mode, not because I think that more ‘superior’, but as my technique it is easier and quicker for me to move the Av and/or the Tv as two independent controls, than to use EC.

My point is it is your whole ‘production line’ which needs to make sense to you, and to work the best for you - AND - you might have two or three typical 'production lines' changeable upon the situation - for example (a guess only), Dan might have something unique, just for his Macro work.

WW

[William W]

. . . I think that many folk don't understand that the choices that THEY make as answers to these questions, are all related, and form their "Technical Procedure". . .

WW

For clarity, for that is a generally directed comment, mainly at "beginners" et al and for the purpose of general considerations, it was NOT directed at Ted, nor any one else, merely using Ted's quote as a springboard for my views.

WW

[rpcrowe]

Actually in the case of exposure, it's the destination that matters, not how you arrive at that destination. If you are consistently getting correct exposures you are doing things right - if your exposures are not consistently good, then you need to look at your techniques or your equipment - most likely it will be the techniques that are at fault.

If your exposure is generally good in some situations but, is not good in other situations - then you need to look at where the fault is. Modern DSLR and mirrorless cameras are very good in calculating exposure - even in full automatic exposure mode in "NORMAL" lighting situations. It is in the other than normal situations such as backlit and high contrast that the brain of the photographer needs to be actively engaged to obtain correct exposures.

Many photographers seem to think that the always need to have their camera in manual mode... What is needed is a comprehensive knowledge of the camera's auto exposure performance so that the photographer will know when the camera's choices need to be modified or overridden completely.

One final thought which will offend many purists. In general shooting, a person who has never touched a camera and who knows nothing about exposure will get very good to excellent exposure results with the camera in the Programmed mode combined with a three stop exposure bracketing. In fact, this is the way I recommended my son in law set up his Canon Powershot SX50HS to shoot an African safari. The results were quite good for someone who has never shot a photo with anything but a cell phone...

[Manfred M]

Richard and Bill - I agree 100% with what both of you have written.

In my view, the part that is missing it to define what a good exposure is and that does depend a lot on definitions and use. I remember having a fairly intense discussion with someone who was vehemently opposed to ETTR (Expose-to-the-Right) claiming that technique lead to people ending up with overexposed images. If one is looking at using a JPEG without further manipulation, then the view that the image looked overexposed was 100% correct. On the other hand, it someone was trying to maximize the data quality for further processing (which is the heart of that technique), then one should accept that the exposure was "correct".

I'm sure we've all seen underexposed images being passed off as being low key and overexposed images being passed off as high key. I've seen a beautifully done snow scape printed on Japanese Washi paper that was "properly exposed", i.e. had a true black point that has 0 value for the blacks and 255 values for the whites, but was so delicate that the bulk of the tones were very light gray through an aggressive approach with the mid-point. The print was exceedingly effective, but many people would have argued that the exposure was incorrect.

The wonderful part of modern camera technology is that there are often a number of different ways to approach the way we photograph a scene and personally I don't care how the final result is achieved, so long as it works.

[rpcrowe]

I previously mentioned, "Actually in the case of exposure, it's the destination that matters, not how you arrive at that destination. If you are consistently getting correct exposures you are doing things right - if your exposures are not consistently good, then you need to look at your techniques or your equipment - most likely it will be the techniques that are at fault."

There can be an equipment angle to the above. Some more modern mirrorless and DSLR camera have a greater ability to register shades of dark and light without blowing out the highlights or totally losing detail in the dark areas.

Additionally, these cameras also have ISO capabilities which were not even dreamed of when I was shooting film and cannot be matched by earlier digital equipment.

It would behoove any serious photographer to experiment with his/her equipment in order to get a good idea of capabilities of that equipment which will be matched by the P.P. of the workflow. Little things like shooting in RAW can help as well as effectively using a noise reduction program in P.P.

In other words, what is the maximum ISO the photographer will accept in his or her imagery. This will definitely have a relationship to the ISO capabilities stated by the manufacturer but, it is a purely personal decision. I use ISO levels far above what I even considered would be acceptable early in my photographic career. I remember when film at ISO 125 was considered "high speed"

It is also very beneficial to have a good idea of the dynamic range of your camera for your idea of acceptable images. Often we can shoot images which have a lowered dynamic range by using fill flash in portraiture, GND filters and even CPL filters for landscapes and by simply selecting images that are within the camera's capabilities...

[William W]

. . . In general shooting, a person who has never touched a camera and who knows nothing about exposure will get very good to excellent exposure results with the camera in the Programmed mode combined with a three stop exposure bracketing. . .

Agree 100%.

The Bracket, if possible, is valuable insurance.

Just a comment on "Program Mode" - indeed it is a very useful option.

You (Richard) might remember Nadine Ohara; she was a very experienced Wedding and Portrait Photographer, very active on another forum.

A few years ago that forum used to get lots of questions from novice Wedding Photographers, some seemingly with little practical experience and less technical knowledge.

Nadine would advise that IF one HAD to cover a Wedding with less than adequate experience and skills, then to use always Program Mode / Evaluative Metering (Matrix=Nikon), (and she'd provide aditional advice re Flash).

At the least Program Mode would reap satisfactory/workable Exposures for nearly every shot.

WW

[William W]

. . . It would behoove any serious photographer to experiment with his/her equipment in order to get a good idea of capabilities of that equipment which will be matched by the P.P. of the workflow.

Sage.

I refer to this as knowing or identifying the 'limits'.

WW

[rpcrowe]

Today's camera systems would have awed the expert photographers of past days...

I remember when Aperture Priority (on some cameras) and Shutter Speed Priority (on other cameras) were the only two semi automatic exposure systems available. In fact one camera, the Pentax ME, had only Aperture Priority available while its brother, the Pentax MX, had only manual exposure available.

Then came a breakthrough... I think that it was Canon that introduced Programmed Auto exposure with the AE-1P or it may have been with its big brother the Canon A-1...

I shot with the Canon A-1 DSLR for years and that camera had a choice of Shutter Priority, Aperture Priority, Programmed Auto, and Manual Exposure systems. Pretty well the same as most of today's DSLR or Mirrorless cameras...

Most detractors of the Programmed Automatic system decried it because they assumed that the photographer needed to accept whatever the camera selected as the final exposure. In fact, with Programmed Automatic you are offered the entire spectrum of shutter speeds or f/stops to select from. You can then adjust the exposure up and down using + and - exposure compensation.

IMO. the problem with any auto exposure system is that the exposure will vary according to the background. An example of this is in shooting a bird in flight against the sky and then having that bird fly in front of some darker vegetation.

Exposure lock will help combat the fluctuating exposure but, IMO, the best way to solve that problem is to determine the correct exposure for the bird and shoot in manual.

Other times when manual exposure is the best, and perhaps the only way, to shoot is when you are using off camera flash... This is true whether you are using that flash in manual mode or in TTL mode. A really neat way to bridge the manual flash to TTL mode is with some Flashpoint/Godox units such as the TTL-360. You can establish a base exposure with the flash in the TTL setting and then switch that setting over to manual (either to adjust the setting or to hold it as it is).

Another way to determine exposure is to select the shutter speed and f/stop manually and choose Auto ISO to determine exposure. I do this very often when I am shooting sports when I want to keep a certain shutter speed to freeze the action and also choose an f/stop which will provide the DOF that I desire. Some camera systems are better at this than others so, it is not a panacea for all systems. I like to be able to place limits on the ISO being chosen...

We are in a fortunate position with modern cameras in that we have so many different systems for determining exposure (as well as for determining focus). The trick is to select which one or which of several systems that will mesh with your way of shooting and to learn how to effectively use the systems available. One system is not the best for the entire myriad of venues in which we shot...