Question about exposure and Zone System?

Using your grey card just means you are determining the exposure that places the card in Zone 5 for tonality/density. You need to then decide if that is where you want other 18% grey reflectance items in your scene to be in Zone 5. If yes, then you are set. If no, then you need to increase or decrease your exposure accordingly. Using your spot meter to analyze the scene will help you decide on the exposure required to place the brightest portion of the scene that will contain detail and the darkest portion of the scene that will contain detail. Even though you camera can record 10-14 stops of dynamic range, unfortunately, the real world has a far larger dynamic range and yo need to decide what part of that range you will record to communicate the scene as you see it in your mind's eye. There is no such thing as a "correct" exposure. There is only the exposure you decide that will give you the final image you want to record.

You need to get a better understanding of the Zone System and how to effectively apply it. It is not really that hard or mysterious. You just pick parts of your scene and decide how bright or dark you want them in your photograph and then set your exposure accordingly.

Get a copy of Ansel Adams' book "The Negative" at your local library or used book store. It is geared toward film, but the concepts very easily translate to digital. The scene analysis method described is fully applicable regardless of film or digital. It will take a little time and practice to get the hang of it, but you will be glad you did. Just be thankful that you don't have to go through the nonsense of messing around with test exposures on film and using a densitometer to calibrate your camera lens and film like I did years ago before digital came along.

Have fun. It sounds like you are moving in the right direction

HarrisLegola said:

Hello photographers, I would like to ask a question on exposure.

In a variety of settings, I can spot meter off of several shades and tones in a scene and the camera will adjust its exposure around that tone, viewing it as middle gray.

This is the part that I hoped to understand better: given the camera captures 14 stops of dynamic range, when I expose for a tone in the scene - pale skin on someone's cheek for example - did I just tell the camera to view that skin as middle grey when I balance the meter to 0.0,

Click to expand...

Yes.

HarrisLegola said:

and then the camera will capture all tones within a +/- 7 stop brightness range around the skin?

Click to expand...

No.

HarrisLegola said:

It's just a bit hard to define for me. For example, when exposing for really bright or dark tones, like snow or a black cat, the camera meter can be tricked and sometimes you need to over or under expose to make the scene look more natural.

Click to expand...

Correct.

HarrisLegola said:

So under that same concept, is that why we use a grey card to set exposure, because it's generally regarded at 50% brightness so it's "balanced"? If I balance a grey card at +/- 0.0 in my camera's spot meter, did I just make the setting to capture all tones under correct exposure for that specific intensity of lighting reflecting off of the gray card?

Click to expand...

A grey card is traditionally about 18% reflectance because this is a "typical" value for everyday subject matter.

You also ask about the Zone System. This was devised by Ansel Adams to suit the dynamic range of b&w film. It is not directly relevant to digital photography, just as it wasn't relevant to colour transparency film (which had a much lower dynamic range than b&w negative film).

The important thing to remember with digital cameras is that you get a sharp cutoff when you overexpose, unlike b&w negative film which had great latitude for overexposure and still recorded some detail in subjects that were badly overexposed.

So, it's best to stick to digital and not confuse the matter by thinking too much about Ansel Adam's Zone System.

The digital equivalent to the Zone System is known as ETTR (Expose To The Right), which aims to choose that exposure which makes the brightest part of the scene just on the verge of overexposure. It's explained in detail in this article:

http://www.dpreview.com/articles/6641165460/ettr-exposed

HarrisLegola said:

Hello photographers, I would like to ask a question on exposure.

In a variety of settings, I can spot meter off of several shades and tones in a scene and the camera will adjust its exposure around that tone, viewing it as middle gray.

This is the part that I hoped to understand better: given the camera captures 14 stops of dynamic range, when I expose for a tone in the scene - pale skin on someone's cheek for example - did I just tell the camera to view that skin as middle grey when I balance the meter to 0.0, and then the camera will capture all tones within a +/- 7 stop brightness range around the skin?

Click to expand...

No, it will not. At about 2-⅔ to 3 stops above middle gray, your sensor will saturate and you'll lose all texture and color: you'll just get white.

But all of that extra dynamic range will be found in the shadow tones; with modern digital cameras you can pull up a lot of shadow detail.

For this reason there is the Expose to the Right (ETTR) methodology, where you adjust your exposure in order to preserve significant highlights. This might make your 'middle gray' significantly darker that you want, but then you can pull up the midtones and shadows on the computer while preserving the highlights.

HarrisLegola said:

It's just a bit hard to define for me. For example, when exposing for really bright or dark tones, like snow or a black cat, the camera meter can be tricked and sometimes you need to over or under expose to make the scene look more natural.

Click to expand...

Yes. That's because the camera has no idea how much the objects in your scene reflect light, although Canon and Nikon cameras attempt to guess at the scene content when using matrix metering.

HarrisLegola said:

So under that same concept, is that why we use a grey card to set exposure, because it's generally regarded at 50% brightness so it's "balanced"? If I balance a grey card at +/- 0.0 in my camera's spot meter, did I just make the setting to capture all tones under correct exposure for that specific intensity of lighting reflecting off of the gray card?

Click to expand...

Correct.

Well, the '50% gray' card looks like a gray tone midway between white and black, but actually it has a reflectance of about 12% or 18%. Our eyes don't have a linear response to light, and instead we are more sensitive to gradations in dark tones.

HarrisLegola said:

So going by that train of thought, if I was in a pitch black room with only two identical spotlights with the same intensity, one in the foreground shining on a flower, and one in the IMMEDIATE background shining on a rock (as to render the inverse square law negligible), and I exposed for a gray card in the foreground underneath the first spotlight next to the flower, I would have also exposed correctly for the rock in the background right? Does this mean I have just placed both the flower and rock in Zone 5 so that their reflectance is around middle grey, and then if I want to place them both in Zone 6 I would turn up my compensation by 1 stop?

So does that mean that by exposing correctly for any object under a specific intensity of light (with a grey card as my reference tone), I will have also set the correct exposure for any other parts of the scene underneath that specific intensity of light? So I can just shoot a gray card once and I'm done?

Click to expand...

You only get one exposure, so you have to set it right to cover the entire scene adequately.

Ah! That's exactly the information I was looking for!

I do understand the ETTR method, and now I see it's because the sensor captures an uneven distribution of brightness around the middle grey reference point. It's more sensitive to shadows.

Okay, I was wondering if you could elaborate on the experiment with the flower and the rock?

Even if it is two lights in different positions, shining on objects with different tones, as long as the lighting is the same intensity and I exposed for the gray card in either light, the flower and the rock would have their tones exposed for correctly right?

So given a background of pure white snow with a lone black cat in it, instead of metering off of the snow and adding stops or off the cat and stopping down, I can simply shoot a gray card instead and that's the same thing?

HarrisLegola said:

So going by that train of thought, if I was in a pitch black room with only two identical spotlights with the same intensity, one in the foreground shining on a flower, and one in the IMMEDIATE background shining on a rock (as to render the inverse square law negligible), and I exposed for a gray card in the foreground underneath the first spotlight next to the flower, I would have also exposed correctly for the rock in the background right? Does this mean I have just placed both the flower and rock in Zone 5 so that their reflectance is around middle grey, and then if I want to place them both in Zone 6 I would turn up my compensation by 1 stop?

So does that mean that by exposing correctly for any object under a specific intensity of light (with a grey card as my reference tone), I will have also set the correct exposure for any other parts of the scene underneath that specific intensity of light? So I can just shoot a gray card once and I'm done?

Click to expand...

That is essentially correct if the illumination of the scene is everywhere the same and the scene contains no sources of light, nor objects that produce specular reflections (highly polished surfaces).

If that is the case, then using the exposure from your grey card will mean pure white objects (100% reflectance) will be just on the verge of overexposure and your camera will also capture very dark objects provided they are not so dark that they go beyond the dynamic range of your camera.

However, using a grey card may not always give you the ideal exposure. Specular reflections can be too bright and will be overexposed, so detail in those bright spots will be lost. In that case, it may produce a better image if the exposure is reduced.

Also, if everything in the scene is very dark (e.g. you want to photograph a heap of coal), and there is nothing very light in colour, then the image will be of better quality if you increase the exposure somewhat (but not so much that it looks unnatural or becomes overexposed). There are two reasons for doing that. First is that the noise in the image will be reduced by increasing the exposure. Second is that the devices available for viewing images (computer screen, etc, or prints) all have a lower dynamic range than a good camera.

Mark Scott Abeln said:

You only get one exposure, so you have to set it right to cover the entire scene adequately.

Click to expand...

I once took 3 exposures of a scene [at different settings] and later combined them to get more than 14-stops of DR. ;-)

Tom Axford said:

HarrisLegola said:

So going by that train of thought, if I was in a pitch black room with only two identical spotlights with the same intensity, one in the foreground shining on a flower, and one in the IMMEDIATE background shining on a rock (as to render the inverse square law negligible), and I exposed for a gray card in the foreground underneath the first spotlight next to the flower, I would have also exposed correctly for the rock in the background right? Does this mean I have just placed both the flower and rock in Zone 5 so that their reflectance is around middle grey, and then if I want to place them both in Zone 6 I would turn up my compensation by 1 stop?

So does that mean that by exposing correctly for any object under a specific intensity of light (with a grey card as my reference tone), I will have also set the correct exposure for any other parts of the scene underneath that specific intensity of light? So I can just shoot a gray card once and I'm done?

Click to expand...

That is essentially correct if the illumination of the scene is everywhere the same and the scene contains no sources of light, nor objects that produce specular reflections (highly polished surfaces).

If that is the case, then using the exposure from your grey card will mean pure white objects (100% reflectance) will be just on the verge of overexposure and your camera will also capture very dark objects provided they are not so dark that they go beyond the dynamic range of your camera.

However, using a grey card may not always give you the ideal exposure. Specular reflections can be too bright and will be overexposed, so detail in those bright spots will be lost. In that case, it may produce a better image if the exposure is reduced.

Click to expand...

I've always believed that it was OK for specular reflections to be blown. If you don't allow that, the picture looks really crappy! Take a picture of a car in bright sunlight. The chrome will bounce an image of the big light in the sky. It's VERY bright! If you meter off those highlights, the rest of the picture is almost BLACK!!!

Tom Axford said:

Also, if everything in the scene is very dark (e.g. you want to photograph a heap of coal), and there is nothing very light in colour, then the image will be of better quality if you increase the exposure somewhat (but not so much that it looks unnatural or becomes overexposed). There are two reasons for doing that. First is that the noise in the image will be reduced by increasing the exposure. Second is that the devices available for viewing images (computer screen, etc, or prints) all have a lower dynamic range than a good camera.

Click to expand...

chuxter said:

Tom Axford said:

However, using a grey card may not always give you the ideal exposure. Specular reflections can be too bright and will be overexposed, so detail in those bright spots will be lost. In that case, it may produce a better image if the exposure is reduced.

Click to expand...

I've always believed that it was OK for specular reflections to be blown. If you don't allow that, the picture looks really crappy! Take a picture of a car in bright sunlight. The chrome will bounce an image of the big light in the sky. It's VERY bright! If you meter off those highlights, the rest of the picture is almost BLACK!!!

Click to expand...

Well, I would agree with you: often specular reflections are just small points of light and it is often ok for them to be blown. But see this recent thread for a situation where getting the exposure right is not easy even with tiny specular reflections.

However, there are some cases where the specular reflections are much bigger and an important part of the image. For instance, bright clouds reflected in the glass windows of a modern building with a lot of glass. Simply using a grey card to meter exposure may fail totally in such a situation.

There are many other similar circumstances.

Basically you have it right (I think).

I spent a lot of time many years ago trying to understand (not so hard) and apply (harder) the Zone System. If you knew how to use it, it gave you a way to predict what parts of a wide dynamic range scene (greater than the DR of the film) would have detail based on how you set your exposure. To do it right, you had to spot meter a whole bunch of places in the scene, decide what in the scene you wanted to be Zone 5, set the exposure for that, etc. Then, the negative would come out with exactly the density you wanted in the parts of the scene where you wanted it. As I remember, it could also be used in the darkroom but I forget how.

It seems to me that if you have Live View, all of this is now unnecessary. You simply look at the LCD and/or the histogram (or even better, the "blinkies") and you can see exactly what parts of the scene will be blown out or underexposed to the point where there is no detail. You then adjust the exposure compensation dial until you get detail where you want it, and no detail where you don't care about it.

Done.

So I am not quite sure what you would use the Zone System for today. I'm sure someone could postulate a scenario where it would be useful but I can't think of one with a Live View camera or DSLR with Live View function.

TEdolph

In My Opinion, you're over-thinking the whole thing. I blame it on the "digital" influence: the belief that everything is now numerical and therefore can be calculated.

Exposure was, is, and doubtless always will be, a judgment call. Adams' Zone System characterized the behavior of specific B&W negative film and print paper, and pushed most of the judgment part into determining what was in which zone and what it was that the photographer wanted to achieve.

With digital sensors, there's not much need for characterizing. Most sensors (a few older Fujis differ) have a hard cutoff for max brightness. Essentially all sensors are linear in response from there down. End of characterization for capture.

For printing... well, that's another story for another time.

Conceptually, Expose to the Right is the optimal approach for sensors. You set the brightest parts of the image that you want to maintain detail in to be just below the sensor cutoff. Realistically, though, that's very difficult to achieve reliably across a range of lighting situations. And with modern sensors, the advantages are virtually invisible except on extreme images.

For most photography, it's far more practical to aim for a pleasing exposure using the in-camera JPEG conversion, and let the Raw data fall where they may. With digital you have the ability to examine the captured image immediately, along with a histogram and blinkies (albeit JPEG-based), so extensive pre-calculation and pre-visualization of exposure tends to be a waste of time.

And when in doubt, there's always Eliot Elisofon's suggestion for getting the best exposure: "it would help if you bracket the hell out of it."

tedolf said:

I spent a lot of time many years ago trying to understand (not so hard) and apply (harder) the Zone System. If you knew how to use it, it gave you a way to predict what parts of a wide dynamic range scene (greater than the DR of the film) would have detail based on how you set your exposure. To do it right, you had to spot meter a whole bunch of places in the scene, decide what in the scene you wanted to be Zone 5, set the exposure for that, etc. Then, the negative would come out with exactly the density you wanted in the parts of the scene where you wanted it. As I remember, it could also be used in the darkroom but I forget how.

It seems to me that if you have Live View, all of this is now unnecessary. You simply look at the LCD and/or the histogram (or even better, the "blinkies") and you can see exactly what parts of the scene will be blown out or underexposed to the point where there is no detail. You then adjust the exposure compensation dial until you get detail where you want it, and no detail where you don't care about it.

Done.

So I am not quite sure what you would use the Zone System for today. I'm sure someone could postulate a scenario where it would be useful but I can't think of one with a Live View camera or DSLR with Live View function.

Click to expand...

I agree.

I never think in terms of zones and instead just concentrate on the maximum exposure that I can get away with.

One issue is that we have three color channels, and these (especially the red and blue channels) are amplified greatly during raw processing. I often allow either the red or blue channels to be 'overexposed' according to my histogram, while they actually are just fine in the raw channels. I simply pull down the highlights to get everything right in my final JPEG.

chuxter said:

Mark Scott Abeln said:

You only get one exposure, so you have to set it right to cover the entire scene adequately.

Click to expand...

I once took 3 exposures of a scene [at different settings] and later combined them to get more than 14-stops of DR. ;-)

Click to expand...

Indeed. HDR can be a good technique.

HarrisLegola said:

Ah! That's exactly the information I was looking for!

Click to expand...

Great!

HarrisLegola said:

I do understand the ETTR method, and now I see it's because the sensor captures an uneven distribution of brightness around the middle grey reference point. It's more sensitive to shadows.

Click to expand...

Well, sensors actually have a rather linear sensitivity to light (not quite exactly, but close), and the signals from the sensors actually are mathematically linearized during processing.

This leads to the unfortunate fact that half the sensor data is dedicated to just the brightest stop of light, while half of all that's left is dedicated to the next brightest stop, and so forth and so on, so that very little data is dedicated to the shadows.

That's unfortunate because human vision is more sensitive to the shadows than to the brights. So what cameras do is to encode the data so that more bits are allocated to the shadows and fewer to the highlights. This is called gamma encoding, and it is efficient because we can use fewer bits of data while still producing an image with good tonality.

HarrisLegola said:

Okay, I was wondering if you could elaborate on the experiment with the flower and the rock?

Even if it is two lights in different positions, shining on objects with different tones, as long as the lighting is the same intensity and I exposed for the gray card in either light, the flower and the rock would have their tones exposed for correctly right?

Click to expand...

I don't quite understand what you are getting at.

In direct sunlight, the illumination of all things in the light is going to be the same, and so you can use a gray card just about anywhere in the scene, as it has the same illumination. I suppose if we are quite sure that the two lights in your scene does the same thing then we can put the gray card in either light stream. But I'd worry a bit because it might be hard to guarantee that both light sources will provide the same illumination.

HarrisLegola said:

So given a background of pure white snow with a lone black cat in it, instead of metering off of the snow and adding stops or off the cat and stopping down, I can simply shoot a gray card instead and that's the same thing?

Click to expand...

Yes.

There are things that are called incident meters, which you hold in the hand at the subject and point to the camera. This eliminates the reflectivity of the subject and only takes the illumination into account.

Your camera has a reflective meter, and so it is very dependent on the reflectivity of the subject. Pointing it at a gray card will basically eliminate this variably reflectivity, and replace it with a standard reflectance, making your camera close to acting like an incident meter.

But with digital photography, this isn't nearly as important, since the cost of taking a photograph is rather low: I estimate roughly ½ to 1-½ U.S. cents per shot based on the lifetime of shutters. You can simply take a photograph and check your image and histograms for good exposure. If you have Live View or a Mirrorless camera, you can even check the exposure before you take the photo.

The main issue with using a gray card is that digital cameras have very little latitude for overexposure, much less than with negative film in the old days (although similar to what was found with slide film). I often find myself underexposing more than I would have with film.

Thanks, that was a great explanation. Yes, I was just trying to visualize some examples where the reflectance would be standard across the scene under even lighting - that's what I meant.

A quick follow-up on your sensor explanation though,

so you're saying that actually, the mechanics of the sensor use 1/2 + 1/2 of a half = 3/4 of its range to capture the highlights, and then 1/4 of its range to capture the shadows?

So it actually spends more effort to capture the highlights than the shadows?

It's just that because our eyes are of logarithmic sensitivity to light, the camera then gamma encodes the image such that the shadows are more represented and the highlights are more easily blown out?

Sorry, just got a bit confused because from the first explanation it seemed like the sensor captured LESS highlights. I don't know if it just LOOKS like way because of the gamma encoding?

HarrisLegola said:

so you're saying that actually, the mechanics of the sensor use 1/2 + 1/2 of a half = 3/4 of its range to capture the highlights, and then 1/4 of its range to capture the shadows?

So it actually spends more effort to capture the highlights than the shadows?

It's just that because our eyes are of logarithmic sensitivity to light, the camera then gamma encodes the image such that the shadows are more represented and the highlights are more easily blown out?

Sorry, just got a bit confused because from the first explanation it seemed like the sensor captured LESS highlights. I don't know if it just LOOKS like way because of the gamma encoding?

Click to expand...

A perfectly linear sensor would act like this:

1st stop: ½ of sensor data

2nd: ¼

3rd: 1/8

4th: 1/16 <- Zone 5?

5th: 1/32

6th: 1/64

etc. Reality is a bit more complicated than this, but this is roughly what happens. The placement of Zone 5 varies between camera makes and camera settings, but understand that you'll probably have no more than two or three stops of headroom above the exposure based on a middle gray card.

Gamma encoding, as commonly used in JPEG images, will reduce the raw data from 12 or 14 bits per color channel to 8 bits per channel, but will rearrange the tones so that more of that data is allocated to darker values.

Human sensitivity tends to follow a power law:


The gamma compression of JPEGs typically use a power law. I'm not sure what percent of the data is allocated to each stop, but that should be fairly easy to calculate.

Tom Axford said:

chuxter said:

Tom Axford said:

However, using a grey card may not always give you the ideal exposure. Specular reflections can be too bright and will be overexposed, so detail in those bright spots will be lost. In that case, it may produce a better image if the exposure is reduced.

Click to expand...

I've always believed that it was OK for specular reflections to be blown. If you don't allow that, the picture looks really crappy! Take a picture of a car in bright sunlight. The chrome will bounce an image of the big light in the sky. It's VERY bright! If you meter off those highlights, the rest of the picture is almost BLACK!!!

Click to expand...

Well, I would agree with you: often specular reflections are just small points of light and it is often ok for them to be blown. But see this recent thread for a situation where getting the exposure right is not easy even with tiny specular reflections.

However, there are some cases where the specular reflections are much bigger and an important part of the image. For instance, bright clouds reflected in the glass windows of a modern building with a lot of glass. Simply using a grey card to meter exposure may fail totally in such a situation.

Click to expand...

While the term "specular reflection" is correct in your example, it is not what most of us call "specular". What I was describing is a pin-point of light from the light source, reflection off a mirror-like surface. Like this:





Taking the picture you mention is no different than taking a picture of clouds. They should never be blown.

Mark Scott Abeln said:

HarrisLegola said:

Ah! That's exactly the information I was looking for!

Click to expand...

Great!

Mark S Abeln said:

I do understand the ETTR method, and now I see it's because the sensor captures an uneven distribution of brightness around the middle grey reference point. It's more sensitive to shadows.

Click to expand...

Well, sensors actually have a rather linear sensitivity to light (not quite exactly, but close), and the signals from the sensors actually are mathematically linearized during processing.

This leads to the unfortunate fact that half the sensor data is dedicated to just the brightest stop of light, while half of all that's left is dedicated to the next brightest stop, and so forth and so on, so that very little data is dedicated to the shadows.

That's unfortunate because human vision is more sensitive to the shadows than to the brights. So what cameras do is to encode the data so that more bits are allocated to the shadows and fewer to the highlights. This is called gamma encoding, and it is efficient because we can use fewer bits of data while still producing an image with good tonality.

Mark S Abeln said:

Okay, I was wondering if you could elaborate on the experiment with the flower and the rock?

Even if it is two lights in different positions, shining on objects with different tones, as long as the lighting is the same intensity and I exposed for the gray card in either light, the flower and the rock would have their tones exposed for correctly right?

Click to expand...

I don't quite understand what you are getting at.

In direct sunlight, the illumination of all things in the light is going to be the same, and so you can use a gray card just about anywhere in the scene, as it has the same illumination. I suppose if we are quite sure that the two lights in your scene does the same thing then we can put the gray card in either light stream. But I'd worry a bit because it might be hard to guarantee that both light sources will provide the same illumination.

Click to expand...

Why would that be difficult? It seems like a trivial thing to do...

Mark S Abeln said:

Mark S Abeln said:

So given a background of pure white snow with a lone black cat in it, instead of metering off of the snow and adding stops or off the cat and stopping down, I can simply shoot a gray card instead and that's the same thing?

Click to expand...

Yes.

There are things that are called incident meters, which you hold in the hand at the subject and point to the camera. This eliminates the reflectivity of the subject and only takes the illumination into account.

Your camera has a reflective meter, and so it is very dependent on the reflectivity of the subject. Pointing it at a gray card will basically eliminate this variably reflectivity, and replace it with a standard reflectance, making your camera close to acting like an incident meter.

But with digital photography, this isn't nearly as important, since the cost of taking a photograph is rather low: I estimate roughly ½ to 1-½ U.S. cents per shot based on the lifetime of shutters.

Click to expand...

Shutters last about 150,000 operations. They cost about $400 to replace. That's $0.002667 per shot.

Mark S Abeln said:

You can simply take a photograph and check your image and histograms for good exposure. If you have Live View or a Mirrorless camera, you can even check the exposure before you take the photo.

The main issue with using a gray card is that digital cameras have very little latitude for overexposure, much less than with negative film in the old days (although similar to what was found with slide film). I often find myself underexposing more than I would have with film.

--
http://therefractedlight.blogspot.com

Click to expand...

chuxter said:

Why would that be difficult? It seems like a trivial thing to do...

Click to expand...

Well, you could do it with a light meter, but that's begging the OP's original question, as to whether or not a gray card would equally meter both lights.

chuxter said:

Shutters last about 150,000 operations. They cost about $400 to replace. That's $0.002667 per shot.

Click to expand...

I was thinking about the price of an entirely new camera, in a more expensive price range. But yes, your numbers are right.

Mark Scott Abeln said:

chuxter said:

Why would that be difficult? It seems like a trivial thing to do...

Click to expand...

Well, you could do it with a light meter, but that's begging the OP's original question, as to whether or not a gray card would equally meter both lights.

Click to expand...

Even easier: Simply buy two IDENTICAL lights. :-0

It's pathological to measure IDENTICAL things to prove that they are IDENTICAL...

Mark S Abeln said:

Mark S Abeln said:

Shutters last about 150,000 operations. They cost about $400 to replace. That's $0.002667 per shot.

Click to expand...

I was thinking about the price of an entirely new camera, in a more expensive price range. But yes, your numbers are right.

--
http://therefractedlight.blogspot.com

Click to expand...