EV where and when?

[mw0dbb]

Hi all, just wondering when you would adjust EV? Is it used to compensate for lack of light?

John

 

[redhed17]

Whenever you need to. :shrug:

If you take a picture and it's too dark, add some 'plus'. If your picture is too bright, add some 'minus'. If it is still not right, add more or less, and try again. :shrug: Hopefully, after awhile you may work out how much to add, rather than trial and error.

The camera gets the exposures pretty good, most of the time, EV is a quick adjustment for when it has gone wrong. Once you have finished in that situation, reset it back to zero, because like I said, the camera gets it right, most of the time.

 

[philthejuggler]

Classic example is a snow-scene. The camera will adjust for an '18% grey' average scene and the snow will look grubby - add some exposure and all will be well.

Phil

 

[ernesto]

Another example is photographs in a town at night. The camera will overdo them and make them too bright and unnatural so need so -ve exposure to correct it.

 

[Pookeyhead]

Hi all, just wondering when you would adjust EV? Is it used to compensate for lack of light?

John

As others have said, it's to compensate for when the meter doesn't give the right results. The trick is knowing when to use it. Have a read of this... second chapter.

Snow is a good example.. the meter sees all that white, and assumes you can't possibly want everything white, so tries to force underexposure.

It's only really useful when working in either Auto, Aperture Priority, or Shutter Priority though. If you're in full manual, it's a lot faster to just to under, or over expose yourself. In auto and semi auto modes, you HAVE to use it as the camera will always be setting either the shutter speed or aperture to give what IT thinks is the correct exposure.

 

[Phil V]

Although the above are kinda right, they follow the misundstanding in the question.

EV is what's measured by the light meter (exposure value) it's a fixed figure, based on the amount of light hitting the light meter.

You act upon that measurement so what changes is EC (exposure compensation), by setting EC in semi auto modes or as above in Manual.

Oops some more were posted I hadn't seen.

 

[MJWC1]

Another good example is backlighting. If you are photographing someone with the sun or other bright light behind them and meter for the whole scene, the gave will be underexposed. So, either use manual or exposure compensation to increase the exposure, fill flash to light the face or spot metering to take the reading from the face.

Like most things it all depends on the actual situation and knowing how to feel with situations that fool the meter its a big part of the technical part of photography. Your brain its far more powerful than any camera!

 

[Tugster]

Once you know how you metering works, you will automatically know how much to adjust the compensation.

 

[redhed17]

Once you know how you metering works, you will automatically know how much to adjust the compensation.

'You will automatically know how much'! You'll probably understand which way to change it, but I don't think you will 'automatically know' how much.

 

[mw0dbb]

I take it the metering is for light? I always thought is was focusing! I am still learning mind!

John

 

[tijuana taxi]

LADS = light add and dark subtract

Easy way to remember, read it in a book a while back and stuck with me

Classic snow example mentioned above, also find it better having EV adjustable by 1/3 stop, bit easier to fine tune

 

[Bassit]

Are there any disadvantages to using EC adjustments, does it introduce noise etc..

Phil, i read the other day that you don't like to use spot metering, any chance you can explain why, i have started to use this quite a lot thinking it would be the best to use in most awkward situations.

 

[redhed17]

Are there any disadvantages to using EC adjustments, does it introduce noise etc..

If you are in Aperture Priority mode then to let in more or less light with the EV, the Shutter speed is adjusted. If you want more light in to brighten (add plus EV) the exposure, it will do this by lengthening the Shutter speed, so you have to keep an eye that the Shutter speed isn't dropping to a point where you can't hold it steady.

Noise should only be a problem if Auto ISO is added to the mix, as that may kick in if your Shutter speed in the example above drops below 1/60th sec.

 

[Bassit]

Cheers redhed, so if i adjust the EC plus or minus, it will adjust the shutter speeds either way, this was going to be my next thread on here but i thought i may as well ask in here seeing as its an appropriate thread, my question would of been is there any advantage to just adjusting the shutter speed as opposed to changing the EC settings, but it seems they both achieve the same thing (changing the shutter speed), apart from changing the EC is more dangerous for someone as absent minded as myself because ill probably forget to change it!

 

[Phil V]

Are there any disadvantages to using EC adjustments, does it introduce noise etc..

Phil, i read the other day that you don't like to use spot metering, any chance you can explain why, i have started to use this quite a lot thinking it would be the best to use in most awkward situations.

The main thing about metering is to understand how it works.

There are 2 methods of spot metering, place the spot over an 18% grey area or place the spot over a subject that you can calculate the setting for and then set the EC to fit; lighter than mid +, darker than mid -.

Call me lazy but I'd learned how matrix and centre weighted worked before I got a reliable spot meter. And trying to assess and remember spot meter settings is too much for my old brain when I have known working methods of metering and there's always new interesting stuff to learn.

There's lots of people who use it successfully though so don't let my foibles put you off learning it.

 

[Bassit]

Thanks for your reply Phil, i think i will have a look at what courses are available near to me and maybe sign up for a couple, i like learning and i think the idea of learning the technical side of photography was part of my being drawn to it in the first place, but my impatience is starting to get the better of me, that and the lack of any structure to my learning. :nuts:

 

[Tugster]

'You will automatically know how much'! You'll probably understand which way to change it, but I don't think you will 'automatically know' how much.

With experience of your own kit you you will have damn close idea.....don't you ? I know I do.

 

[redhed17]

With experience of your own kit you you will have damn close idea.....don't you ? I know I do.

A 'damn close idea' is a bit different than ''automatically know'.

Cheers redhed, so if i adjust the EC plus or minus, it will adjust the shutter speeds either way

Ignoring ISO, and assuming it is set at a specific value, if you are in Aperture Priority mode, changing EV changes the Shutter speed. In Shutter Priority mode, the Aperture changes to let in more or less light when changing the EV value. In either mode, if the thing that is auto changing to compensate starts flashing, it is warning you it is getting too much or too little light because it has reached the limit of available adjustments.

Set your camera in Shutter Priority to 1/4000th sec, half press the shutter, and in the viewfinder you should see the Aperture value flashing as it has opened the Aperture much as it could, and it is not getting enough light, and in this case will under expose and is alerting you to the problem. You could try the other way too by setting the Shutter to 30" (seconds) and in this case the shutter is open for so long that the camera uses its smallest Aperture to reduce the amount of light, and here the Aperture value will flash because it is getting too much light. If nothing flashes, you should get a pretty accurate exposure.

this was going to be my next thread on here but i thought i may as well ask in here seeing as its an appropriate thread, my question would of been is there any advantage to just adjusting the shutter speed as opposed to changing the EC settings, but it seems they both achieve the same thing (changing the shutter speed), apart from changing the EC is more dangerous for someone as absent minded as myself because ill probably forget to change it!

I'm not sure I understand this bit.

 

[Phil V]

Why is everyone discussing exposure compensation (EC)

EV - Exposure Value - the wiki article.

Apologies to the OP, the question does appear to relate to EC (Exposure Compensation) which most of the above should help with. But I always believed that for people to get an understanding of a technical concept, it's useful if everyone uses the same language.

 

[Pookeyhead]

Why is everyone discussing exposure compensation (EC)

EV - Exposure Value - the wiki article.

Apologies to the OP, the question does appear to relate to EC (Exposure Compensation) which most of the above should help with. But I always believed that for people to get an understanding of a technical concept, it's useful if everyone uses the same language.

Because that's probably what he means, as EV is just an arbitrary exposure value made up from reciprocal combinations of aperture and shutter speed at any given ISO... it's not something you can adjust in camera.. except manually of course .. but there's no EV control. ALL your controls are EV controls.

He's clearly referring to EC.

 

[Phil V]

B...

He's clearly referring to EC.

But if no-one points out the difference he'll carry on believing the term was used correctly. Surely it's better to educate properly (you're welcome).

 

[tijuana taxi]

He's clearly referring to EC

What's Eric Clapton got to do with it?

 

[redhed17]

Why is everyone discussing exposure compensation (EC)

Because the +/- button is sometimes referred to as the EV button. :shrug:

 

[Pookeyhead]

well quite... that too. Seems pointless being pedantic about it in light of that. Bloody Canon!

Makes sense though in a way... "Exposure Value compensation" is essentially the same as just saying "Exposure Compensation".

 

[Phil V]

Because the +/- button is sometimes referred to as the EV button. :shrug:

Does that not say EV Comp?

It's the comp that's the impo...

Forget it:bonk:

 

[Pookeyhead]

That's what I said in the post above yours

 

[redhed17]

Makes sense though in a way... "Exposure Value compensation" is essentially the same as just saying "Exposure Compensation".

I know. Try to explain it to group of people, and some are saying what is EV, and some are saying what is Exposure Compensation? :bang:

Bloody Canon

Tell me about it. They have to do things different to everyone else. A = Av, S =Tv and Auto is a green square. :bonk:

And if you want more evidence, look at the icons they use for their metering modes. Surprise surprise, different to everyone else. :bang:

 

[Phil V]

I know. Try to explain it to group of people, and some are saying what is EV, and some are saying what is Exposure Compensation? :bang:



Tell me about it. They have to do things different to everyone else. A = Av, S =Tv and Auto is a green square. :bonk:

And if you want more evidence, look at the icons they use for their metering modes. Surprise surprise, different to everyone else. :bang:

Is it not that they need to avoid not using the same terms due to people being precious about IP?

Like Nikon lenses zoom in the wrong direction?

Anyway - the important part of the phrase is still

exposure value compensation which means the same as
exposure compensation
whereas
exposure value compensation is a completely different concept to
exposure value

 

[redhed17]

Is it not that they need to avoid not using the same terms due to people being precious about IP?

IP?

Like Nikon lenses zoom in the wrong direction?

Of course in this case, it's everyone else who does it the wrong way.

Anyway - the important part of the phrase is still

exposure value compensation which means the same as
exposure compensation
whereas
exposure value compensation is a completely different concept to
exposure value

When trying to explain things to beginners, there is quite a lot of confusing jargon anyway, and it would be a great help if everyone stuck with the same terminology and icons for the same things. :shrug:

 

[Bassit]

I think we was all talking about the same thing.
If not then i am really confused..

IP - intellectual property.

 

[Phil V]

When trying to explain things to beginners, there is quite a lot of confusing jargon anyway, and it would be a great help if everyone stuck with the same terminology and icons for the same things. :shrug:

It's Exposure Compensation, I don't know what else to say, the only reason the terminology is being discussed is that the OP used EV, and several people answered his question without correcting the term.

I may have caused the confusion, by insisting people should be more accurate with terminology, but it's better for the OP to get it right from the start, rather than have to unlearn later.

 

[shaylou]

Are there any disadvantages to using EC adjustments, does it introduce noise etc..

Phil, i read the other day that you don't like to use spot metering, any chance you can explain why, i have started to use this quite a lot thinking it would be the best to use in most awkward situations.

You do not want to use spot metering often because it only averages a very small portion of the picture. In other words the spot will be exposed correctly but the rest of the picture most likely will not.

I would think if you are using spot metering for most of your shots your exposures would be off. Are you sure that you are not referring to spot focusing?

 

[skysh4rk]

You do not want to use spot metering often because it only averages a very small portion of the picture. In other words the spot will be exposed correctly but the rest of the picture most likely will not.

I would think if you are using spot metering for most of your shots your exposures would be off. Are you sure that you are not referring to spot focusing?

If you understand how your camera meters, there's no reason why you couldn't use spot metering to get accurate exposures for your photos. If you don't understand metering, then yes, spot metering could be problematic.

 

[shaylou]

If you understand how your camera meters, there's no reason why you couldn't use spot metering to get accurate exposures for your photos. If you don't understand metering, then yes, spot metering could be problematic.

Really doesn't come down to that. Thanks but I understand metering just fine. I just choose like most to meter with what will give the most consistent reading.

 

[Bassit]

You do not want to use spot metering often because it only averages a very small portion of the picture. In other words the spot will be exposed correctly but the rest of the picture most likely will not.

I would think if you are using spot metering for most of your shots your exposures would be off. Are you sure that you are not referring to spot focusing?

Thanks for the advice .
I don't use it most of the time, just for the more awkward situations.
When using it i find my pics are Generally slightly under exposed but nothing that isn't easily sorted with pp.

If you understand how your camera meters, there's no reason why you couldn't use spot metering to get accurate exposures for your photos. If you don't understand metering, then yes, spot metering could be problematic.

I cant profess to fully understand metering yet but i am a fast learner and very stubborn when it comes to learning, i am getting there but maybe a bit slower than i'd like.

 

[skysh4rk]

Really doesn't come down to that. Thanks but I understand metering just fine. I just choose like most to meter with what will give the most consistent reading.

I was making a general comment. I was not evaluating your metering knowledge, nor was I suggesting that you should use spot metering yourself.

I am just saying that it is misleading to say that spot metering is inconsistent. There's no reason that one cannot get consistent results if one understands how it works.

 

[shaylou]

nor was I suggesting that you should use spot metering yourself.

I do use spot metering in certain situations.

I am just saying that it is misleading to say that spot metering is inconsistent. There's no reason that one cannot get consistent results if one understands how it works.[/QUOTE]

This is my response to your reply and in it I did not say that spot metering was inconsistent, I said I choose to use a more constant metering process.

 

[skysh4rk]

This is my response to your reply and in it I did not say that spot metering was inconsistent, I said I choose to use a more constant metering process.

Errrr, right... so this quote below which implies that spot metering isn't very consistent (i.e., most exposures will be off) isn't from you?

I would think if you are using spot metering for most of your shots your exposures would be off.

 

[skysh4rk]

Thanks for the advice .
I don't use it most of the time, just for the more awkward situations.
When using it i find my pics are Generally slightly under exposed but nothing that isn't easily sorted with pp.

I cant profess to fully understand metering yet but i am a fast learner and very stubborn when it comes to learning, i am getting there but maybe a bit slower than i'd like.

Yeah, that sounds like a good approach. It's perfectly sensible to use matrix metering most of the time, as it's pretty reliable nowadays, but switch to spot metering in trickier situations such as snowy scenes or backlit portraits.

The key for spot metering is to place the spot over a mid-tone (often something grey, but not necessarily) somewhere in the scene, otherwise you could end up under- or over-exposing the photo.

A bit more reading and experimentation will get you there, no doubt.

 

[mw0dbb]

Does setting the metering point also effect the auto focus point?

I find if I am focusing on an object which is quite small then I have to set it to point metering?

John