A-1 EV

I have a basic understanding of what exposure value (EV) is but how does it apply to the A-1, for example, in the following sentence from Canon Manual Focus SLRs by Eric Skopec: "The built-in TTL meter reads from EV-2 to 18." In simple terms, what the heck does that mean?

I believe they used an f1.4 lens at 100 ISO for reference.

The "-2" marks the lowest shutterspeed your camera can measure. The upper end doesn't seem relevant.

Sorry, I can't tell if it will be 4 or more seconds, but your specs sound comparably decent.

For a start, page 46 of the A-1 owners manual has a chart and description.

Simple terms: ISO 100, the meter will couple from 8 sec.@ f1.4, to 1/1000 @ f16.

Edited March 7, 2022 by Bettendorf

Exposure value is not a measure of light intensity, rather it's a number signifying a combination of aperture and shutter speed. It needs the ISO / ASA value specifying to indicate the metered lighting level.

For comparison, the New F1 goes from ev -1 to +20. (4 sec at f1.4 to 1/2000 at f22 with ASA 100) My EFs read down to -2 ev. Put the booster finder on the older F1, and I think it reads to -3.5. If you have/had a Blad, you got used to using EV especially when it came to using fill-in flash. Edited March 7, 2022 by chuck909

Okay. I sort of get it but it seems a bit more information than I really needed to know for what I do - just curious.

Another way to explain it, EV-2 is rather dim light, EV18 is very bright.

 

I wouldn't call them meaningless numbers, but in reality, you'll know when you exceed the A-1's EV range. Something in the viewfinder will start to flash.

. . . In simple terms, what the heck does that mean? . . . it seems a bit more information than I really needed to know for what I do - just curious.

 

Some of the technical information provided by manufacturers is often of little practical use to most users; additionally, some of the technical information provided (seems to me) to be mostly sales motivated and marketing driven. There are so many purchasers who buy items majorly based upon the comparison of technical specs.

 

It seems to me that one practical application for your photography would be the meaning/use of the lower number (EV = -2). A practical "in the field" situation, this number indicates that you might have some issues when attempting to use AE metering for dark scenes, such as but not limited to: rural nightscapes, stars, candlelit scenes, moonlit scenes and the like.

 

Another important practical point is: if the light on/from the scene is too dim for the TTL Light Meter of your A-1 to work efficiently, (as Jim mentioned), there will be a warning displayed in the Viewfinder.

 

WW

Not so long after I got my (then new) Nikon FM, I started to figure this out.

 

For one, I figured that I could set the ASA dial to a different value, meter with that value,

and then expose (with a cable release) for a longer time. But eventually, you run into

some limit.

 

In the case of the FM, the ASA dial and shutter speed dial are coupled, such that some shaft

turns related to the combination. There is a variable resistor, where one side connects to

the ASA-shutter speed dial, and the other to the aperture dial.

 

In the case of the FM, there is no warning when you go past it. The variable resistor is

circular, and so it goes around to the high shutter speed/low ASA position, and still

says underexposed. There are settings where you slow down the shutter, and it

goes from overexposed to underexposed, as it wraps around.

 

In any case, there is a maximum and minimum amount of light that it can meter,

independent of ASA, shutter speed, and aperture setting. It is commonly given

in EV at a specific ASA (in the old days) value.

 

By the way, for easy memory, EV 0 is at f/1 and 1s.

I asked the same question myself--but learning to master the Kodak Retina IIIc cameras, which EV is a dial for setting the camera.

This chart was helpful for me in understanding about EV.

 

Here’s a table showing the EV of different shutter speeds and apertures combinations: