Does changing shutter speed and aperture create equalized exposure?

[smoke665]

Sorry, I should have also mentioned that I still am figuring out the exposure triangle (despite taking analog photos for almost 10 years )

I started my photography journey in the the mid 60s. The Exposure Triangle principles started to crystallize into it's present theory in the early 70s. I would argue thoes principles are just as applicable to film as it is to digital. You just don't have the ability to change on the fly with film.

I just remembered that aperture affects depth of field, so THAT aspect would obviously be different

Aperture changes alone don't necessarily change the DOF. It is a function of focal length, distance to subject, the acceptable circle of confusion size Understanding the Circle of Confusion (BEST guide). and aperture. Changing any of these can decrease, increase or keep your DOF the same.

Would the exposure remain “constant” I guess you could say, by keeping the shutter speed and aperture in balance with one another?

Yes assuming you made corresponding adjustments.

I’ve been wanting to for quite a while. They’re so expensive though
It is on my next-to-buy list though

I rely on my light meter in studio, because it's the only way to measure incident lighting. Outside in ambient lighting they can be difficult to use because of all the stray light. For that I rely on my camera meter in spot mode to sample light in the frame to determine my exposure settings and dynamic range limitations. Modern digital cameras have multiple exposure modes, understanding how each works will help you get a proper exposure Understanding Camera Metering and Exposure. In digital I always seek to get a full data file without blowing the whites as evidenced by the file histogram. However, from experience I know on my cameras I can push the exposure to the point that the histogram just starts to show the highlights being blown without affecting image quality.

 

[cgw]

I’ve been wanting to for quite a while. They’re so expensive though
It is on my next-to-buy list though

Film and processing aren't exactly giveaway-priced. An affordable meter might up your keeper percentage.

 

[Ysarex]

I started my photography journey in the the mid 60s. The Exposure Triangle principles started to crystallize into it's present theory in the early 70s. I would argue thoes principles are just as applicable to film as it is to digital. You just don't have the ability to change on the fly with film.

The Exposure Triangle didn't exist until about the turn of the millennium. It first shows up in Brian Peterson's book Understanding Exposure as The Photographic Triangle (early 1990s). Peterson didn't call it the Exposure Triangle probably because he already knew what exposure was as evidenced by his inclusion of a correct definition of exposure in the book. Here's a correct definition: Exposure (photography) - Wikipedia and the same definition Peterson supplied.

The Internet then caught on to Peterson's "triangle," renamed it the Exposure Triangle, and they were off and running spreading misinformation like wildfire.

The Exposure Triangle (Peterson's Photographic Triangle) can be helpful for beginners learning to control their cameras. However the Exposure Triangle as it is most commonly presented now in uncountable youtube videos and web blogs typically misinforms in a number of ways. Here's a typical example: https://petapixel.com/assets/uploads/2017/03/exposuretrianglediagram.jpg

The exposure triangle as a model makes it's presenters want to balance it and that leads them to misinform.

For example, someone infected with triangulitis will identify the two setting combinations below as producing the same exposure:

A) 1/250th sec, f/5.6, ISO 200
B) 1/250th sec, f/8, ISO 400

In fact the B) settings deliver 1 stop less exposure to the film/sensor than the A) settings.

Look at the diagram I linked above and notice how the author has included the word Light along each edge of the triangle with the words more/less to either side. So following the diagram we can conclude that raising the ISO adds more light to the exposure? I've watched the videos and actually heard them say that.

In their need to balance the triangle people suffering from triangulitis just about wet their pants when they can say that each of the three components of the triangle work together as exposure determinants (that's incorrect) while at the same time controlling a different variable. The shutter controls exposure + motion blur, the aperture controls exposure + DOF and the ISO controls exposure + noise (again incorrect).

The beginner get's some initial help in learning to use their camera controls but at the same time the seeds of misunderstanding and confusion get planted. For example noise in a digital image is primarily a function of exposure while raising ISO in fact suppresses noise. It's hard to explain that to someone who's been triangulated.

Aperture changes alone don't necessarily change the DOF. It is a function of focal length, distance to subject, the acceptable circle of confusion size Understanding the Circle of Confusion (BEST guide). and aperture. Changing any of these can decrease, increase or keep your DOF the same.



Yes assuming you made corresponding adjustments.



I rely on my light meter in studio, because it's the only way to measure incident lighting. Outside in ambient lighting they can be difficult to use because of all the stray light. For that I rely on my camera meter in spot mode to sample light in the frame to determine my exposure settings and dynamic range limitations. Modern digital cameras have multiple exposure modes, understanding how each works will help you get a proper exposure Understanding Camera Metering and Exposure. In digital I always seek to get a full data file without blowing the whites as evidenced by the file histogram. However, from experience I know on my cameras I can push the exposure to the point that the histogram just starts to show the highlights being blown without affecting image quality.

 

[hooray4mo]

Film and processing aren't exactly giveaway-priced. An affordable meter might up your keeper percentage.

I mean, you're not entirely wrong, but the place I take my film to get developed and scanned is very reasonably priced. They also sell film stocks at a lower cost than even amazon or B & H Photo

 

[AlanKlein]

The Exposure Triangle didn't exist until about the turn of the millennium. It first shows up in Brian Peterson's book Understanding Exposure as The Photographic Triangle (early 1990s). Peterson didn't call it the Exposure Triangle probably because he already knew what exposure was as evidenced by his inclusion of a correct definition of exposure in the book. Here's a correct definition: Exposure (photography) - Wikipedia and the same definition Peterson supplied.

The Internet then caught on to Peterson's "triangle," renamed it the Exposure Triangle, and they were off and running spreading misinformation like wildfire.

The Exposure Triangle (Peterson's Photographic Triangle) can be helpful for beginners learning to control their cameras. However the Exposure Triangle as it is most commonly presented now in uncountable youtube videos and web blogs typically misinforms in a number of ways. Here's a typical example: https://petapixel.com/assets/uploads/2017/03/exposuretrianglediagram.jpg

The exposure triangle as a model makes it's presenters want to balance it and that leads them to misinform.

For example, someone infected with triangulitis will identify the two setting combinations below as producing the same exposure:

A) 1/250th sec, f/5.6, ISO 200
B) 1/250th sec, f/8, ISO 400

In fact the B) settings deliver 1 stop less exposure to the film/sensor than the A) settings.

Look at the diagram I linked above and notice how the author has included the word Light along each edge of the triangle with the words more/less to either side. So following the diagram we can conclude that raising the ISO adds more light to the exposure? I've watched the videos and actually heard them say that.

In their need to balance the triangle people suffering from triangulitis just about wet their pants when they can say that each of the three components of the triangle work together as exposure determinants (that's incorrect) while at the same time controlling a different variable. The shutter controls exposure + motion blur, the aperture controls exposure + DOF and the ISO controls exposure + noise (again incorrect).

The beginner get's some initial help in learning to use their camera controls but at the same time the seeds of misunderstanding and confusion get planted. For example noise in a digital image is primarily a function of exposure while raising ISO in fact suppresses noise. It's hard to explain that to someone who's been triangulated.

OK there;s less light on the sensor because the aperture is smaller. But the ISO amps amplify the signal so the end results are the same from a practical perspective. So what point are you trying to make

 

[Ysarex]

OK there;s less light on the sensor because the aperture is smaller. But the ISO amps amplify the signal so the end results are the same from a practical perspective. So what point are you trying to make

The end results are not the same. In the case I used with just a one stop difference there's not a lot of variance in the end result, but exposure (how much light reaches the film/sensor) matters because it's effects show in the end result. As you drop exposure you lose SNR and raising the ISO does not compensate that loss.

The point is understanding cause and effect. A shutter speed change causes a change in exposure. An aperture change causes a change in exposure. An ISO change does not cause a change in exposure and exposure matters.

 

[smoke665]

The Exposure Triangle didn't exist until about the turn of the millennium. It first shows up in Brian Peterson's book Understanding Exposure as The Photographic Triangle (early 1990s). Peterson

I was referencing Peterson's comment's he made in his 4th edition which stated that he started conceptualizing the notion in the 70's. I can't find the references from that far back but I vaguely remember discussion on this in the middle 70s.

The point is understanding cause and effect. A shutter speed change causes a change in exposure. An aperture change causes a change in exposure. An ISO change does not cause a change in exposure and exposure matters.

I would agree with you, as changes to ISO are amplification to the analog signal vs actual increase/decrease in light, with the trade off being as you increase gain on the analog signal from the sensor, you increase noise, the flip side of that is as you increase exposure you increase the SNR which in turn decreases visible noise.

 

[AlanKlein]

The end results are not the same. In the case I used with just a one stop difference there's not a lot of variance in the end result, but exposure (how much light reaches the film/sensor) matters because it's effects show in the end result. As you drop exposure you lose SNR and raising the ISO does not compensate that loss.

The point is understanding cause and effect. A shutter speed change causes a change in exposure. An aperture change causes a change in exposure. An ISO change does not cause a change in exposure and exposure matters.

But the triangle still applies under ordinary circumstances. How else would you set your light meter?

 

[Ysarex]

I was referencing Peterson's comment's he made in his 4th edition which stated that he started conceptualizing the notion in the 70's. I can't find the references from that far back but I vaguely remember discussion on this in the middle 70s.

First edition of that book came out in the early 90s as I recall and Peterson called it then the Photographic Triangle.

The point is understanding cause and effect. A shutter speed change causes a change in exposure. An aperture change causes a change in exposure. An ISO change does not cause a change in exposure and exposure matters.

I would agree with you, as changes to ISO are amplification to the analog signal vs actual increase/decrease in light, with the trade off being as you increase gain on the analog signal from the sensor, you increase noise, the flip side of that is as you increase exposure you increase the SNR which in turn decreases visible noise.

ISO is commonly implemented by amplifying the analog signal from the sensor but that's not the only way it's implemented and that implementation doesn't define ISO. Implemented via amplification of the analog sensor signal ISO suppresses read noise. The shot noise in the signal is not increased or decreased by the action of ISO but it is revealed.

 

[Ysarex]

But the triangle still applies under ordinary circumstances. How else would you set your light meter?

As I noted the Exposure Triangle has a problem that involves contemporary presentation. ISO doesn't cause noise in a digital photograph, but far too many of the folks explaining the triangle on the Internet will say it does. Changing ISO has no effect on the light sensitivity of the camera's sensor, but far too many of the folks explaining the triangle on the Internet will say it does. Photographic exposure (for far longer than we've been alive) is defined as the amount of light falling on the film/sensor per unit area -- a function of scene luminance, shutter speed and aperture. Changing ISO does not change the amount of light falling on the film/sensor but far too many of the folks explaining the triangle will it say it does.

So does it apply if ISO is not a causal component of exposure? Can the triangle be presented by starting with a correct definition of exposure?

Go to youtube, do a search on exposure triangle and watch a random 20 of them. It's pretty much a guarantee that you'll be misinformed 20 times. New photographers don't realize they're being misinformed and maybe they'll be OK and little harm will be done, but why start beginners off with false info?

I've had numerous occasion to have to help someone re-learn because they were getting poorer quality photos from their cameras having learned the exposure triangle off the Internet.

 

[LWW]

This may be related to bracketing, but I’m not quite sure. Also I’m not sure if I worded this in the right way, so bear with me.
Say for instance you take a photo with a camera mounted to a tripod at a shutter speed of 1/500 and your aperture is set to f/16. You then take another photo of the same subject in the exact same spot with the shutter speed set to 1/250 and your aperture set to f/11. Would the two images have the same exposure, thus looking the exact same? Or at least have the same exposure to them?

Assuming the first exposure was correct, the second be also … however they would not be identical as the aperture change also changed the depth of field.

Any blur in the pictures would also differ slightly.

Nothing, in photography, is everything … but everything is something.

Keep asking and experimenting.

 

[RAZKY]

Changing ISO does not change the amount of light falling on the film/sensor but far too many of the folks explaining the triangle will it say it does.

I don't doubt but that some (probably most!) Utubers are foolish enough to make such a claim, and some folks are naive enough to believe it - should be enough to say that a change of ISO affects the need for a change of exposure. Since getting a Walz selenium-cell meter when I was 12, determining desired exposure has been about the simplest part of photography for me. I hadn't even heard of the "triangle" till fairly recently. Nothing wrong with a bit of humor, though!

 

[smoke665]

Since getting a Walz selenium-cell meter when I was 12, determining desired exposure has been about the simplest part of photography for me.

Not trying to throw a monkey wrench in the works but sometimes the "best" exposure is not so simple. IE: you've metered your scene and determined the DR exceeds the camera capabilities. Do you expose for the highlights and try to recover shadows post, or the focal point knowing you'll blow the highlights? Do you adjust ISO when making your decision? Why? Are you opening up the aperture, if so will you have enough DOF? If you reduce shutter speed will you incur blur? A meter gives you parameters to work with but the photographer determines how they use those parameters.

 

[franks641sub]

Just a noob hear, but the ISO standard implimented in I'm thinkin in the 70's. Was to standardize film. My impression was and still is, goes back to the way I think about it. Back in the day different solutions of a silver solution on glass plates. The "faster" the solution, more of the silver grain was visible..... Low ISO/DIN fine grain ... High ISO/DIN the grain is more coarse. Then the medium changed to the "Silver" being emulsified in what we call film. Same mechanics, just simpler for the masses.
I learned the triangle, it is ingrained, I do always remember what My H.S. Teacher said of exposure though: "Compose your picture, think about what you want to capture, SEE it, create it in your mind. Then snap it. The Art you create is like a painting.. No two are ever the same.

 

[wfooshee]

My understanding of changing the ISO is that it does not change the exposure, as changing only the ISO does not change the amount of light on the sensor, but changing the ISO does change the camera's interpretation of that exposure. If I change aperture from f:5.6 to f: 8, a decrease in exposure of one stop, and change the ISO from 200 to 400, an increase of one stop in sensitivity, the end result will be "the same." Is the exposure the same? No.

The misuse of "exposure" as meaning the result of the exposure, i.e. the presented image, is what's wrong with saying ISO is a leg of the exposure triangle. It's a leg of the "result" triangle.

Personally, I don't use ISO as a factor in my settings other than using appropriate shutter and aperture for the selected ISO, just like using appropriate settings for the loaded film. I use the lowest possible ISO for conditions, and I've never used auto-ISO.