Is 1.4 really necessary for available light?

[sockdaddy]

i understand that EV must mean 'exposure value' or something like that, but how are you guys computing these values based on your camera settings, and what are some guidelines or resources to explain that an EV rating (like your EV 5, etc.) examples?

 

[ghost]

considering how much finer grain modern films have, no, i don't think f1.4 is all that necessary. it helps when you're in a pinch, but sometimes it's not enough and you would have done better with faster film. you'll have your ups and downs, and it's best just to be prepared.

 

[Crasis]

i understand that EV must mean 'exposure value' or something like that, but how are you guys computing these values based on your camera settings, and what are some guidelines or resources to explain that an EV rating (like your EV 5, etc.) examples?

As far as I can tell, EV (Exposure Value) is directly correlated with ISO. EV 0 is defined as a 1 second exposure at f/1.0, with 100 ISO film. So for 1600 ISO film, you have 4 stops more light sensitivity so with your new film you would read EV 4. This would be a 1/15th of a second exposure at f/1.0.

I believe that EV values move depending on your ISO, which moves the shutter speed and aperture values, while LV does not move. You should look this up yourself as I'm probably misremembering some information.

 

[furcafe]

I use a Gossen Digisix as my handheld meter when I'm shooting a meterless body, & all the Gossen meters give readings in EV. Each EV value corresponds to a set of apertures & shutter speed combinations, so if you get a reading of EV 5, for example, you'll know that f/1 is 1/30th, f/1.4 is 1/15th, etc. Obviously, a higher ISO film will give you a greater EV value than a lower ISO film under the same lighting conditions, but the useful thing about EV, @ least if your arithmetic is good, is that it's really independent of ISO & once you memorize an aperture/shutter speed combo for a given EV value you can calculate the whole range of combos for that light level. I think Hasselblad's use the EV system, as did some older post-WWII German cameras (ZI Super Ikonta III & IV, Agfa Super Isolette, etc.) where the aperture & shutter speed rings are linked together so that exposures can be set more quickly, @ least in theory (because the rings need to be disengaged & reset for different EV values, it's really only convenient if light levels aren't changing).

i understand that EV must mean 'exposure value' or something like that, but how are you guys computing these values based on your camera settings, and what are some guidelines or resources to explain that an EV rating (like your EV 5, etc.) examples?

 

[George Bonanno]

FLEXIBILITY and EASY are not options in low light photography. It's a matter of discipline, practice and... controlling your subject !

 

[Crasis]

FLEXIBILITY and EASY are not options in low light photography. It's a matter of discipline, practice and... controlling your subject !

Well, if I had control of my subject, I'd probably control the lighting too. That's a strange thing to say. I never have control of my subjects. I think that would require me knowing them 🙁

 

[Socke]

i understand that EV must mean 'exposure value' or something like that, but how are you guys computing these values based on your camera settings, and what are some guidelines or resources to explain that an EV rating (like your EV 5, etc.) examples?

Here is a very good runup of EVs and how to guestimate exposure:

http://www.fredparker.com/ultexp1.htm

 

[George Bonanno]

Well, if I had control of my subject, I'd probably control the lighting too. That's a strange thing to say. I never have control of my subjects. I think that would require me knowing them 🙁

Sorry Crasis... there is no easy way out. Of course you can control your subject... through keen observation.

 

[Crasis]

Sorry Crasis... there is no easy way out. Of course you can control your subject... through keen observation.

Or a gun to their heads. "ACT NATURAL! Or blood will be naturally pooling from your skulls!"

Nah.. don't think that'd get me the shot I want 😀

 

[IGMeanwell]

Its definitely a choice; I have 1.8 lenses and 1.4 ... I honestly have found instances where that stop makes a difference. Of course that is mostly due to the fact that most of my photography is in incredibly dim conditions since I tend to be nocturnal.

Plus I like the look of shallow DOF .. but thats my preference

 

[varjag]

Just got my 50/1.5 yesterday and took it out for night walk.. after dark even a half stop difference (over 1.8 I was using previously) is very helpful.

Yes, DOF that wide open is shallow, but not any really more limiting in compositional choice than f/2 of a slower lens.

 

[vicmortelmans]

Tonight I was shooting after the sun set. Had FP4+ with yellow filter. If I didn't have a F/1.4 lens, I would have had to stop shooting. But with it I was able to get a few more shots in before it was too dark. Necessary... no; nice to have... definitely.

The other week, I was shooting with my Canonet QL17 GIII, HP5+ and yellow filter. I'm currently overexposing one stop to compensate underdevelopment for the filmscanner (don't know if it works out right, yet). Because of the yellow filter, I had to open it another stop, so I actually was working on ISO100.

It was evening and getting darker so quite soon I had to stop, even wide open at f/1.7. Stupidly, I didn't realise that just removing the yellow filter would have allowed me to shoot for another 15 minutes at ISO200! And even then, I think that I would have gotten away with ISO400 or even ISO800. The underdevelopment and underexposure would cause flat negatives, but tuning scanning and postprocessing, this may still provide decent pictures....

Next time, I think twice before putting the camera away.

Groeten,

Vic

 

[Bromo33333]

As always "it depends" - I never use flash and use successfully have shot lots of rolls using a 50/f2 lens and 28/f2.8. Higher film speed always helps. I suppose it depends upon how much light you want ot use? If you want to shoot at night, the lower the f number, the better, but you are right that the shallow focal plane could be another limitation. Low light is always challenging to get acceptable results - one thing that makes it so much fun!

 

[VinceC]

>>Washington, DC Metro subway system is around EV 7 (inside the cars it's about EV 9 or 10).<<

Furcafe is right! I was surprised at how bright the DC Metro is. This is a shot with 400 speed film using a 28/3.5 Nikkor on my S3. Can't remember shutter speed, but it was probably 1/30.

 

[jlw]

i understand that EV must mean 'exposure value' or something like that, but how are you guys computing these values based on your camera settings, and what are some guidelines or resources to explain that an EV rating (like your EV 5, etc.) examples?

Short primer on EV numbers:

EV (which does stand for "exposure value") is a system for using a single number to represent a whole range of equivalent shutter speed and f/stop settings.

(As you know, many different setting combinations will give the same exposure: for example, f/2.8 at 1/250 will give the same exposure as f/4 at 1/125, f/5.6 at 1/60, f/8 at 1/30, and so on.

The EV number system was devised to give a convenient way to designate all the equivalent combinations. EV 0 designates f/1 at 1 second or any equivalent combination; EV 1 designates f/1.4 at 1 second or any equivalent; etc.) Some cameras and most light meters have a window that reads out the EV for the combination of shutter speed and aperture settings in use.

Higher EV numbers designate less exposure, and lower EV numbers designate [more exposure. Going up or down by one EV number represents a one-stop change in exposure: for example, if you had been shooting at settings equivalent to EV 2, and then stop down two stops, your EV setting will now be 4.​

By itself, the EV number has nothing to do with light levels. It's just shorthand for a group of camera settings. It doesn't tell you anything about the light level used to make a picture.

To understand this, imagine a situation in which your light meter has quit working. You notice another photographer taking pictures, and ask him what exposure s/he is using. The reply: "1/250 at f/5.6." Does that help you know how to set your camera for the same lighting conditions?

No -- because you don't know whether or not s/he is using the same film (or digital-camera ISO setting) as you are. You need that piece of information to know what exposure settings are appropriate for that light level.

It's the same when using EV numbers to talk about light levels or meter sensitivity. To be meaningful, the EV number has to be based on a particular ISO number. By convention, the ISO used is 100.

So when you read, "The light level for this picture was EV 4," what that means is, "The light level was such that to get a correct exposure on ISO 100 film, I'd have to set a combination of shutter speed and aperture that's designated by EV number 4."

For clarity, some careful writers like to use the term light value, or LV, to designate this "EV number at ISO 100" value; in the above example; you'd say, "The light level was LV 4." I applaud this trend, since it helps distinguish between a number that represents a light level (LV) and one that simply represents a combination of camera settings (EV.)​

Most people take pictures in dark places on films considerably faster than ISO 100, so the EV number that represents their camera settings is usually considerably higher than the one that represents the light level. For example, if your meter reads out an LV of 2 (remember that LV numbers assume ISO 100 film) but you're using a film that's 3 stops faster, you'd set your camera controls for an EV of 5.

Clear?

 

[Pherdinand]

As said above, exposure valuye EV is always for iso 100. "EV whatever for iso1600" does not exist. Not trying to be a wise ass but EV is something expressing a correct exposure on iso100 film. If you switch to iso1600, you can still calculate a number that looks like EV but it's not EV.

The problem with LV - light value - is, that almost nobody is using it.

 

[Crasis]

As said above, exposure valuye EV is always for iso 100. "EV whatever for iso1600" does not exist. Not trying to be a wise ass but EV is something expressing a correct exposure on iso100 film. If you switch to iso1600, you can still calculate a number that looks like EV but it's not EV.

The problem with LV - light value - is, that almost nobody is using it.

If I understand what you've said correctly, and I must be for I am reading English and not reading between the lines any, you're saying that if I change from 100 ISO film to 1600 ISO film, the same scene will have the same EV?

Is that right?

Maybe it would be more correct to say that since EV is defined for 100 iso film, switching to 1600 iso film raises the EV by 4 stops.

Therefore, EV at 100 iso is equivalent to EV+4 at 1600 iso.

Maybe the problem is language? If I tell you I'm using EV 10.. what does that tell you? If I tell you I'm using LV 10, well that's standardized. If my light meter reads EV 10, that's for a certain ISO speed, right? If I don't tell you the iso speed (since EV is a combination of shutter and aperture), you'll never be able to set it correctly for your ISO speed.

Are we the ones using it right or wrong, or are the people who make light meters using it right? Does it matter if THEY are wrong when we have to use THEIR products?

 

[Pherdinand]

The same scene will have the same EV because EV is a number for iso100.
You will overexpose your film, though, because EV20 is, e.g., correct exposure for iso1600.
Switching to 1600 does not rise the EV, it is still the same EV number because EV number is defined for iso100.
Switchng to iso1600 means for correct exposure of the iso1600 film you have to increase the EV number with 4 stops.

 

[Pherdinand]

EDIT: but it's really just a convention.
We could say like, EV0 is f/1 and 1 second per iso100.
If you want iso1600, the units are still in "F number and exposure time per iso 100".

 

[Pherdinand]

If I tell you I'm using EV 10.. what does that tell you?

For me it means you have to expose your iso100 film for 1/15 s using f/8 to get "correct" exposure. It also means, if you use 1600 speed film, you have to decrease the exposure with 4 f-stops compared to the above setting. But when you tell me EV10, i don't have to ask "for what film?", i don't care what film you use, because EV is defined for ISO100.