Camera built in spot meter

[Marcelo Paniagua]

I use the averaging function on OM4 at lot. Proven very useful at least for me.

 

[MattKing]

Correct me if I'm wrong @Chan Tran , but I believe that what you are enquiring about is cameras that permit taking several different spot meter readings from different parts of the subject, and then provide a tool that helps you to integrate those readings into a single exposure recommendation.

 

[MFstooges]

The Digital camera also has histograms and blinkies and you can view the LED screen. If any of these indicate the exposure is off, you move the exposure adjustment wheel and you're done. Averaging spots seems like overkill and not needed.

None of analog cameras have histogram display

 

[Chan Tran]

Correct me if I'm wrong @Chan Tran , but I believe that what you are enquiring about is cameras that permit taking several different spot meter readings from different parts of the subject, and then provide a tool that helps you to integrate those readings into a single exposure recommendation.

Yes that is what I was asking about. I was asking about cameras that can take several spot readings then average them like the Olympus OM-4. Not a camera with spot mode and average mode because most modern cameras can accomplish this. (if you want the average mode on a modern camera simply set the center weighted area to full screen).

 

[Paul Howell]

I think the OM 4 and Canon T90 are the only camera with the ability to store multiple spot metering reading, I checked the Pentax LX has only average metering not even spot metering. From Wiki.

To these, Canon copied the metering options found on Olympus' OM-4.[4] Multi-spot metering allows the photographer to average up to eight spot meter readings from different parts of the scene. In another feature borrowed from Olympus, separate Highlight and Shadow spot readings could be taken. These adjust the camera's metering decisions to ensure extremes of tonal range are not muted and grey in the final exposure.

Two built-in sensors are used to implement all these metering options. Center-weighted and partial area metering are performed by a double-area silicon photocell (SPC) in Canon's standard location above the eyepiece, while spot metering is performed by another SPC located at the bottom of the mirror box. Light reaches that sensor via a half-silvered area of the main mirror and a secondary mirror located beneath it. The spot metering cell also allows for automatic TTL "off-the-film" flash metering, again borrowed from Olympus.

 

[xkaes]

None of analog cameras have histogram display

 

[Ardpatrick]

Yes that is what I was asking about. I was asking about cameras that can take several spot readings then average them like the Olympus OM-4. Not a camera with spot mode and average mode because most modern cameras can accomplish this. (if you want the average mode on a modern camera simply set the center weighted area to full screen).

Chan,

I’m sure you have good reason to ask. But 20 years ago when I first got a hand held spotmeter I would take readings from various parts of a scene and average them to get a reading. It was sort of like a matrix meter method, and I soon realized that I would be better off using a camera with actual matrix metering - which would be more consistent!

Now I use the spot meter with medium & large format to read off significant shadows, which I then underexpose by two stops. Shadow details are good and I control highlights through development.

More recently again I started dabbling in using spot metering with an old Nikon N80 I have. Set the camera’s exposure compensation dial to underexpose by 2 stops, and use the spot meter to get a reading in the shadows - Zone III I believe they call it. It’s a sort of point and shoot zone system (!) but at least serves the intended purpose of the camera - to produce test rolls for the purposes of establishing development times for larger formats.

 

[Alan Edward Klein]

None of analog cameras have histogram display

Well, they should add those features.

 

[Alan Edward Klein]

View attachment 379798

No wonder I can't find the place where to load the film.

 

[Paul Howell]

One did, the Minolta 9000 with the accessory back. From Wiki. I have 3 9000 but not he accessory back. I need to add it to my list.

Furthermore, an optional back "program back super 90" (PBS-90) provided multi-spot measurements, with optional automatic weighting by average (AVERAGE), mean (CENTER), highlight (HIGHLIGHT) and shadow (SHADOW), as well as user-definable program curves.[3]

 

[Chan Tran]

Chan,

I’m sure you have good reason to ask. But 20 years ago when I first got a hand held spotmeter I would take readings from various parts of a scene and average them to get a reading. It was sort of like a matrix meter method, and I soon realized that I would be better off using a camera with actual matrix metering - which would be more consistent!

Now I use the spot meter with medium & large format to read off significant shadows, which I then underexpose by two stops. Shadow details are good and I control highlights through development.

More recently again I started dabbling in using spot metering with an old Nikon N80 I have. Set the camera’s exposure compensation dial to underexpose by 2 stops, and use the spot meter to get a reading in the shadows - Zone III I believe they call it. It’s a sort of point and shoot zone system (!) but at least serves the intended purpose of the camera - to produce test rolls for the purposes of establishing development times for larger formats.

When I asked the question I did say I never used the feature although my spot meter has that function. I just wonder why they don't make camera that way any more. Multi spots and averaging is not matrix. Matrix is much more complicated than that. In fact no manufacturer publishes the algorithm for matrix or evaluative.

 

[Paul Howell]

I've never used multi spot metering so I don't if it is any better or worse than matrix metering, that is a good question. My guess is that multi spot meter reading while better in some instances, takes time to learn when and how to use it, what is the rational for picking which 6 to 8 points to meter and average. And perhaps more costly to produce than matrix mode.

 

[Ardpatrick]

When I asked the question I did say I never used the feature although my spot meter has that function. I just wonder why they don't make camera that way any more. Multi spots and averaging is not matrix. Matrix is much more complicated than that. In fact no manufacturer publishes the algorithm for matrix or evaluative.

Indeed I didn’t really get the difference between multi-spot and matrix at the time. I do now. But I still couldn’t say when multi-spot reading would be better than matrix readings. Maybe that question is another thread.

 

[koraks]

But I still couldn’t say when multi-spot reading would be better than matrix readings

Matrix is basically a black box. It tells you what the camera believes will be the 'correct' exposure. How accurate that is and whether you would have reached the same conclusion if you had done some spot measurements, you'll never know.

Multi-spot can be used to estimate the scene brightness range in a straightforward and quick manner. Personally I generally limit the measurements to 3 or 4. E.g. in a typical landscape scene, I'd meter the main subject area, an important shadow and a part of the sky to get a feeling for how the values are spread across the scene. I'll then make an informed choice on how to expose, also based on what kind of film I'm shooting and what kind of result I'm after.

Matrix is faster and doesn't require much mental effort. Multi-spot is more deliberate and gives more control, but takes more time.

 

[Ardpatrick]

Matrix is basically a black box. It tells you what the camera believes will be the 'correct' exposure. How accurate that is and whether you would have reached the same conclusion if you had done some spot measurements, you'll never know.

Multi-spot can be used to estimate the scene brightness range in a straightforward and quick manner. Personally I generally limit the measurements to 3 or 4. E.g. in a typical landscape scene, I'd meter the main subject area, an important shadow and a part of the sky to get a feeling for how the values are spread across the scene. I'll then make an informed choice on how to expose, also based on what kind of film I'm shooting and what kind of result I'm after.

Matrix is faster and doesn't require much mental effort. Multi-spot is more deliberate and gives more control, but takes more time.

in a typical landscape scene, I'd meter the main subject area, an important shadow and a part of the sky to get a feeling for how the values are spread across the scene. I'll then make an informed choice on how to expose, also based on what kind of film I'm shooting and what kind of result I'm after.

Helpful Koraks. Without wanting to hijack the thread, can I ask how you synthesize that information to make an informed choice?

I ask because I’ve simplified my own approach to finding an appropriate shadow area to place in zone 3, and expose accordingly. I take highlight spot readings to monitor scene dynamic range and if I’m shooting sheet film I process accordingly in my Jobo to get full tonal range printable negatives. I shoot B&W negative these days and have a standard developer (ID11 1+1) with specific times established for each film / exposure situation. This approach is basically “expose for the shadows & develop for the highlights.” For me it’s reliable and efficient.

But how does a reading of the ‘main subject area’ influence your final exposure if it’s a midtone say, and not also the most significant highlight / shadow? My question assumes you’re shooting B&W neg of course. Maybe you use a variety of developers? Or are referring to digital?

I guess to justify my query in this thread context - I’m pondering the real world value of multi-spot readings. No doubt it’s useful - I would better like to understand how.

 

[loccdor]

While the very advanced metering that came later is accurate most of the time, I have noticed there are common situations that can confuse it. For instance, when my Canon Elan 7E detects "sunset colors", it lowers the exposure quite a bit, as this makes sunsets look like they should. However, if your intended subject is not the sunset itself, perhaps a person in front of it or some landscape/architecture, you lose a lot of the details.

I believe how matrix/evaluative metering works (or at least part of it), is that it essentially trains an algorithm on thousands or millions of exposures, matching the input light to the "best" exposure on a wide variety of scenes. That means if you have a scene that strongly seems like one of those common scene archetypes, but isn't, it's going to treat it like it's that. Handles the probable cases well, but not the outliers that buck the trends.

 

[koraks]

can I ask how you synthesize that information to make an informed choice?

Depending on what I shoot, what end result I want, what materials I'm using...there's no hard & fast rule. Exposure is essentially a compromise, so I try to strike the best balance for a given situation. The multi-spot thing helps in doing this, but I essentially do the same thing regardless (and don't we all, in the end).

But how does a reading of the ‘main subject area’ influence your final exposure if it’s a midtone say, and not also the most significant highlight / shadow? My question assumes you’re shooting B&W neg of course. Maybe you use a variety of developers? Or are referring to digital?

I shoot mostly B&W negative and color negative, but the materials vary and so do my aims. Limiting to the multi-spot thing which exists in my hands only on my Canon T90, I'll try to compromise within the inherent limitation that I'll have 36 frames that all need to come out sort of OK. So then it depends on what I'm shooting - if I have Fomapan 400 in the camera (unlikely) I'll avoid having any meaningful shadows under -1 because I know it'll be mush. If it's Vision3 250D, however, I know I can 'get away' with allowing the shadow areas to drift down quite a bit before things become unprintable.

I'll also inform my choice based on how I think I'll print the thing, which especially comes into play if the SBR is either very small or very large. With a very small SBR (at least on B&W film), I might err to underexposure a little bit since there won't be any shadows that drop off the scale anyway. I'll end up with a somewhat thin negative, but that's fine because I know that sort of negative prints quite nicely on a high grade. If the SBR is large and there are some 'peak highlights' (think of a cloud formation that's relevant, or brightly lit walls in an otherwise more subtly lit scene), I'll try to prevent those highlights from ending up too far up the curve, because that's where things tend to get compressed, which I generally don't really like. So I then use my metering of the main subject area to see how far I can allow this area to drift down onto the curve. I might sacrifice some shadow detail in the process. Or maybe I'll do the opposite and allow some of the highlights to slope off into poor separation because I need to prevent some relevant shadow detail from sagging into the film's toe. Depends on the scene, depends on the film, depends on how I think I can optimize the print.

So there's really no straight answer, except "it depends". There's no rule. There's a number of principles and preferences, and the inherent randomness of the real world. I try to smash that together into what I hope is a workable compromise when I press the button.

As to the usefulness of multi-spot: if I take 3-4 readings of important spots in the scene, I can see how far the extremes are apart, and also whether some of those measurements bunch together quite closely. It helps me from being confused by colors or subjective impressions by giving me an objective reading of reflectance (I might experience a bright red cloth as very bright, while the grey chair it's draped on in reality has the exact same reflectance - multi-spot helps me to realize that in an efficient way). Etc. etc.

In the end, multi-spot does nothing that you can't do with a single spot meter and a decent memory. It just removes the 'burden' in terms of the latter as the camera remembers the measurements for me and presents them in a neat little list that I can intuitively shift up and down.

Don't let any of this fool you into thinking I'm a magician or an expert in terms of exposure. Like any photographer who has pushed the button a sufficient number of times, I walk away with not too much unintended variance on a roll of film. At the same time, I f*** up just like the next guy or gal from time to time. I mess up development, make mixing errors; I'm sloppy, nonchalant or hasty at times, sometimes I just can't be bothered to do it right - and much of the time, I experiment, and some of those times I do so while knowing very well that the experiment is not going to be an improvement over the tried-and-tested approach. The 'informalness' of all this is one of the things that keeps me going as an amateur (!!) photographer.

Or are referring to digital?

Digital is easy; just press the button and check on the screen that nothing is blown out since that's pretty much the only thing you can't fix in digital. All the rest is flexible. I don't bother with true spot metering on digital. Mostly I'll leave it on evaluative or at best partial metering and poke around for a few seconds, press the button and see what I got. Then back home I can dump the 450 frames I feel s*ck @s$ and fix the remaining 50 into something presentable (with generally better technical quality than I ever get from 35mm film, how's that!) Maybe there's going to be a guy (usually a guy) who comes along and tells us all "it isn't so" and exposure for digital is "super duper critical", "it's like exposing for slide film", but really...I don't think so. It's not critical. Just don't blow out the whites, that's all.
(No innocent pixels were harmed in the writing of this post).

 

[Ardpatrick]

Thanks for such a considered reply!

I can grasp the value of multiple spot readings as a way of profiling the tonality of a scene as film responds to it, rather than how we faultily perceive it. But I also sense a lot of information being generated which can be confusing and can skew the calculations.

Once I’m confident that my film speed rating works to deliver shadows without compromising highlights overly, and that my meter / camera are ‘proven’ I know I can just find the lowest significant shadow detail, measure off it and place it in zone 3. If the highlights are 5 stops or higher above that, experience tells me to restrict development to prevent dense highlights. By separating the two stages - exposing for shadows, and later developing with consistency for highlights, it feels manageable.

 

[koraks]

I think we all have our own ways, and most of them work just fine.

Was it Kertész who judged his night-time exposures along the lines of "hmm, this feels like a two-cigarette exposure"? That was multiple spot, too. Multiple cigarettes in the same spot.

 

[Alan Edward Klein]

We all mess up exposures. Me too. Especially if I'm shooting chromes in difficult light such as during magic hour. If I'm shooting landscapes with a MF, then I'll bracket. It's cheap insurance. A roll of 120 is reactively inexpensive. With 4x5, I tend to take a chance with one shot.

As I mentioned, lately I use a digital camera as a meter with spot, center and matrix exposure readings, although I mainly use center. Center allows more deliberate checking of various areas of the scene. PLus you can move the needle just moving the camera a little into lighter or darker areas. Having a histogram, blinkies, and LED view provides a lot of information on where to set the exposure. Another thing I noticed, is that the blinkies on the high end come on about 2 -2 1/2 stops above gray normal which kind of fits in with chrome stops total range of around 5. If I get the blinkie on the high end, I figure I;m at or close to clipping the whites and back off unless it;s a very minor area.

 

[Ardpatrick]

I think we all have our own ways, and most of them work just fine.

Was it Kertész who judged his night-time exposures along the lines of "hmm, this feels like a two-cigarette exposure"? That was multiple spot, too. Multiple cigarettes in the same spot.

Agreed. Many ways to arrive at the image.

 

[Ardpatrick]

We all mess up exposures. Me too. Especially if I'm shooting chromes in difficult light such as during magic hour. If I'm shooting landscapes with a MF, then I'll bracket. It's cheap insurance. A roll of 120 is reactively inexpensive. With 4x5, I tend to take a chance with one shot.

As I mentioned, lately I use a digital camera as a meter with spot, center and matrix exposure readings, although I mainly use center. Center allows more deliberate checking of various areas of the scene. PLus you can move the needle just moving the camera a little into lighter or darker areas. Having a histogram, blinkies, and LED view provides a lot of information on where to set the exposure. Another thing I noticed, is that the blinkies on the high end come on about 2 -2 1/2 stops above gray normal which kind of fits in with chrome stops total range of around 5. If I get the blinkie on the high end, I figure I;m at or close to clipping the whites and back off unless it;s a very minor area.

I can see how useful this is. My wife bought an Olympus micro 4/3 some years ago - I wasn’t impressed! But it has its uses as you point out. I do prefer porting around only a light meter though - as opposed to a second camera.

 

[Paul Howell]

Are there any handheld meters with a matrix mode?

 

[Chan Tran]

Are there any handheld meters with a matrix mode?

So far not but if they do they should have an exposure preview mode as well for film. You will have to program in the characteristic curves of the film in the meter then it would display on its screen the image.

 

[wiltw]

The Olympus OM-4 and OM-3 were the first to have built in spotmeter (I think) and they can do an average of several readings. All modern cameras have spotmetering but none I know has the averaging function. My handheld spotmeter has the function but I never used it. I wonder if anyone uses it?

The use of spotmeter averaging can be applied in several ways...

Average several 'midtones' ...which might actually NOT be 'middle tone' to the meter because the mind's perception differs from reality
Note what your eye thinks is 'middle tone' vs. what a spotmeter finds...

Note that only three color patches exactly matched the 18% gray reference value.

The use of spotmeter averaging can find the mid-point exposure as the simple average of 'highlight, with detail' and 'shadow, with detail' ares within a scene that you wish to preserve, regardless of the incident meter's exposure value indicated.

I use the multispot metering on the OM-4, and while my Minolta Spotmeter F can average two readings, it does not have multi-spot capability.
The Canon EOS 3 and digital Canon EOS-1D C has multispot capability