Trying to understand the reasoning behind different schools of thought regarding EV in determining exposure

[Alan Edward Klein]

I doubt that there are any cameras out there that have built in meters and use EV scales.
A lot of the cameras that separate selenium meters that weren't coupled - e.g. Retinas - used EV scales.
EV is an incredibly useful way of expressing exposure - a set of combinations of aperture and shutter speed that are of equal effect (assuming no reciprocity issues).
EV is not a measure of light - it is a measure of camera exposure.
If we are in two different cities, thousands of miles away, I can tell you what combination of settings works for something, and you can get the same results in terms of exposure.
If, however, you need to know what to set your camera to, you need to measure the light, and then factor in the speed of your film. That will tell you whether the EV combination I just shared with you is the right one for you, or whether you need to set your camera to a different EV combination.
The dials/digital scales on meters do that conversion for you. But if you are Ansel Adams without a meter up on top of his car (there he is again) and know what the right exposure combination (EV) for the moon is for one ASA, you can easily translate that to EV that works the same with the ASA film in the camera.

Next time I'm on the top of my car with my camera howling at the moon, I'll wish I knew EV's better.

 

[MattKing]

Next time I'm on the top of my car with my camera howling at the moon, I'll wish I knew EV's better.

If you have me on the phone and have a candlepower light reading, you can tell me what film speed you are using and I can give you all the correct aperture and shutter speed combinations by quoting one EV number

 

[Alan Edward Klein]

EV works with all ISO unless you use the Pentax meter which only works for ISO 100. My Minolta Viewmeter 9 EV works for all ISO although it's a very primitive meter.

Telling someone what the EV is does not tell them anything unless you tell them the ISO as well.

 

[Alan Edward Klein]

If you have me on the phone and have a candlepower light reading, you can tell me what film speed you are using and I can give you all the correct aperture and shutter speed combinations by quoting one EV number

I understand that. But for practical reasons, how does knowing the EV help you set the aperture and shutter in the field while using your own meter? It seems reading the shutter and aperture directly off the meter seems easier.

 

[DREW WILEY]

What's all the fuss about? Lux meters are sometimes used in studio sets, and in architectural lighting applications, but EV meter readout is applicable to every single lens and type of film I can think of, and highly intuitive. Pentax meters are popular in Hollywood. It's all I've used for the past 45 yrs. Yes, you set your ASA first. That's just routine, regardless. I once had a Minolta Spotmeter F. It read identically with the Pentaxes right across the scale. 1 EV change equals 1 full stop or shutter speed change. How much simpler can it get?

 

[Alan Edward Klein]

What's all the fuss about? Lux meters are sometimes used in studio sets, and in architectural lighting applications, but EV meter readout is applicable to every single lens and type of film I can think of, and highly intuitive. Pentax meters are popular in Hollywood. It's all I've used for the past 45 yrs. Yes, you set your ASA first. That's just routine, regardless. I once had a Minolta Spotmeter F. It read identically with the Pentaxes right across the scale. 1 EV change equals 1 full stop or shutter speed change. How much simpler can it get?

How do you know what aperture and shutter speed to set on your lens without cross-referencing a chart or memorizing it?

 

[DREW WILEY]

It tells you all the relevant combinations right on the dial. You set your ASA earlier, which stays the same, locked into position, unless you change it. Take your reading looking through the spotmeter lens. Transfer that reading to whatever position you want it on the dial, relative to shadow or highlight placements, or middle gray, and then just look at whatever shutter speed or f-stop you want to use. Takes mere seconds. As easy as it gets. And for those who want to use the Zone System, it can't get any more intuitive than using one of these. No need to modify them.

 

[BrianShaw]

I have a Mamiya RB67 6x7. I don't like the square format of Hassies. Or their EV's scales.

Well then… ignore EV… it does not apply to your photography.

 

[BrianShaw]

EV works with all ISO unless you use the Pentax meter which only works for ISO 100. My Minolta Viewmeter 9 EV works for all ISO although it's a very primitive meter.

I think it’s long been known that Pentax made errors: omission of important details related to EV in the instructions plus erroneously marking their exposure calculator.

 

[Sirius Glass]

Next time I'm on the top of my car with my camera howling at the moon, I'll wish I knew EV's better.

Hasselblad PME prisms read out PME only.

 

[Chan Tran]

How do you know what aperture and shutter speed to set on your lens without cross-referencing a chart or memorizing it?

Calculate it in your head. Take the Pentax meter for example. What you read in the viewfinder I would call it LV and it's equal to the EV for ISO 100. If you are not using ISO 100 film then add 1 for every stop of higher film speed. For example if the meter needle shows 9 and you using ISO 400 then the EV is 11. From EV 11, pick an aperture or shutter speed then you can calculate the other in your head to 1/3 stops increment.

 

[Alan Edward Klein]

It tells you all the relevant combinations right on the dial. You set your ASA earlier, which stays the same, locked into position, unless you change it. Take your reading looking through the spotmeter lens. Transfer that reading to whatever position you want it on the dial, relative to shadow or highlight placements, or middle gray, and then just look at whatever shutter speed or f-stop you want to use. Takes mere seconds. As easy as it gets. And for those who want to use the Zone System, it can't get any more intuitive than using one of these. No need to modify them.

I don't use the Zone system. So I read aperture and shutter speed right on the dial and transfer them to the lens. EV serves no point.

 

[Alan Edward Klein]

Calculate it in your head.

My head is busy remembering what film I have in the camera.

 

[MattKing]

I don't use the Zone system. So I read aperture and shutter speed right on the dial and transfer them to the lens. EV serves no point.

Which one of the many combinations.
An EV based set of dials shows you all the available ones that meet the necessary exposure criteria, and allow you to choose amongst them.
A camera like a Retina IIIc builds that right in.

 

[Alan Edward Klein]

Which one of the many combinations.
An EV based set of dials shows you all the available ones that meet the necessary exposure criteria, and allow you to choose amongst them.
A camera like a Retina IIIc builds that right in.

Overkill.

 

[BrianShaw]

Overkill.

Some say that. But that really means something when written by someone who both understands and has used it. Otherwise…

If you are happy with your personal photographic process and results, then be happy. That’s all that really matters.

 

[Chan Tran]

Some say that. But that really means something when written by someone who both understands and has used it. Otherwise…

If you are happy with your personal photographic process and results, then be happy. That’s all that really matters.

But then I had this Polaroid 150 which I can only set the EV and it has only 1 combination of shuter speed/aperture for each EV value. The EV is quite useful.

 

[Bill Burk]

OK I tried it on my cellphone app and the EV changes when I change the ISO. But I don't see any advantage of working with EV, especially since I use different film with different ISO's. The settings on my lenses are in shutter speed and f aperture. Why screw around with EV?

I think you understand now. f/stops and shutter speeds capture the imagination but EV abstracts these in a way that the mind can’t process. A camera, like the Rollei, Hasselblad or my Polaroid 110B conversion has all three.

The usefulness only exists when you pair the camera that supports it with a light meter that does, like my Weston Ranger 9 with its clearly marked Exposure Value.

You take one number from the light meter, instead of two. <- this is the chief advantage!

Unlock, set the EV on the camera by moving the f/stop -or- shutter speed while looking at the EV pointer.

Then set the lock.

Don’t unlock if the light doesn’t change.

Now you fiddle with the camera settings with f/stop and shutter speeds linked so a single click to faster shutter opens the f/stop one stop, or go the other way and stop down the lens and the shutter speed follows to a slower speed.

Some cameras like OM put both shutter and f/stop in a way that you can hold both with a wide grasp and turn them both together.

I have never used the lock, I always use f/stop and shutter speed numbers from the meter. It’s just something that came late and never caught on.

Of course electronic shutters came in about the same time and made things even easier.

 

[BrianShaw]

Some cameras like OM put both shutter and f/stop in a way that you can hold both with a wide grasp and turn them both together.

Ahhh… the first truly digital EV lock… finger-powered!

 

[Alan Edward Klein]

I think you understand now. f/stops and shutter speeds capture the imagination but EV abstracts these in a way that the mind can’t process. A camera, like the Rollei, Hasselblad or my Polaroid 110B conversion has all three.

The usefulness only exists when you pair the camera that supports it with a light meter that does, like my Weston Ranger 9 with its clearly marked Exposure Value.

You take one number from the light meter, instead of two. <- this is the chief advantage!

Unlock, set the EV on the camera by moving the f/stop -or- shutter speed while looking at the EV pointer.

Then set the lock.

Don’t unlock if the light doesn’t change.

Now you fiddle with the camera settings with f/stop and shutter speeds linked so a single click to faster shutter opens the f/stop one stop, or go the other way and stop down the lens and the shutter speed follows to a slower speed.

Some cameras like OM put both shutter and f/stop in a way that you can hold both with a wide grasp and turn them both together.

I have never used the lock, I always use f/stop and shutter speed numbers from the meter. It’s just something that came late and never caught on.

Of course electronic shutters came in about the same time and made things even easier.

I get it, Bill. For cameras with interlocks, the EV could be handier. But what if you add a filter and have to open up 2 stops or added a polarizer that you want to add 1 3/4 stops? Then don't you have to disengage the lock, an extra step, to change either the shutter or aperture? Isn't it easier just to deal with these settings independently and ignore EV?

 

[Doremus Scudder]

I get it, Bill. For cameras with interlocks, the EV could be handier. But what if you add a filter and have to open up 2 stops or added a polarizer that you want to add 1 3/4 stops? Then don't you have to disengage the lock, an extra step, to change either the shutter or aperture? Isn't it easier just to deal with these settings independently and ignore EV?

I think it is. That and the fact that I have no shutters with an EV-lock is why I've never bothered with the system.

Bracketing is harder with the EV lock on, as is making adjustments for filtration, etc. This, however, only on shutters that lock aperture and shutter speed together. Otherwise whether your meter reads in EV or LV, you simply use the dials to find an aperture/shutter-speed combination you want and apply that manually.

Personally, I don't care what the number in the display of my meter refers to as long as I can set it on the calculator dial and get a choice of valid aperture/shutter-speed combinations. Heck, the display could read out in letters or abstract symbols as far as I'm concerned; I just need to be able to convert those using the calculator dial.

Doremus

 

[BrianShaw]

Bracketing is harder with the EV lock

That's a true fact. Probably the only downside to using an EV interlock equipped camera.

 

[Bill Burk]

Absolutely easier to not use EV. f/stops and shutter speeds are easy to visualize once you get the hang of it.

The only time I ever lock the EV on the camera or use the EV value on the light meter is to add to the discussion of threads like this.

 

[BrianShaw]

f/stops and shutter speeds are easy to visualize once you get the hang of it.

EV is easy to visualize once you get the hang of it, also.

Both get the job done... f/stops and shutter speed on any shutter and EV only on EV interlock shutters.

 

[Sirius Glass]

I think it is. That and the fact that I have no shutters with an EV-lock is why I've never bothered with the system.

Bracketing is harder with the EV lock on, as is making adjustments for filtration, etc. This, however, only on shutters that lock aperture and shutter speed together. Otherwise whether your meter reads in EV or LV, you simply use the dials to find an aperture/shutter-speed combination you want and apply that manually.

Personally, I don't care what the number in the display of my meter refers to as long as I can set it on the calculator dial and get a choice of valid aperture/shutter-speed combinations. Heck, the display could read out in letters or abstract symbols as far as I'm concerned; I just need to be able to convert those using the calculator dial.

Doremus

That's a true fact. Probably the only downside to using an EV interlock equipped camera.

Not a problem. Once a combination has been choose, unlock the EV and change for bracketing.