650D metering mode problem?

[letsgofishing]

R2D2 wrote:

letsgofishing wrote:

In addition your camera has a function called Live View. A feature almost Custom Built for shooting scenics, as the image on the LCD will reflect whatever settings you select on the camera. Give this method a whirl next time you're out. You'll become a very Happy Camper, guaranteed.

I was using live view and that's what threw me - what it showed was nowhere neaar the actual the actual lighting of the scene!

That's because "the image on the LCD will reflect whatever settings you select on the camera."

Which in this case was the Evaluative Metering setting. And thus the camera will "think" that a dark object in the center of the frame is your backlit subject (ie a person), and will increase the exposure accordingly.

Avoid this camera "guesswork" by not using Evaluative Metering, EVER.

You'll be a stronger (and happier) photographer for it!

R2

Thanks - definitely using partial or spot from now on!

 

[letsgofishing]

iancrowe wrote:

letsgofishing wrote:

"It's because you think the meter can know what your idea of "right" is, that it should know that you don't want a standard, normal, average, everyday, 18% grey, 50% reflective image brightness. It can't read your mind, you have to tell it what you want."

Surely if this is the case, then if I photograph a white, a grey and a black piece of card, then the metering should reproduce them as all the same grey value?? i.e. it will "average out" the light in the scene?

Apologies if I'm being a PITA....

Absolutely correct.

In best Blue Peter mode here are some I prepared earlier.

All were shot in diffuse daylight Av mode and evaluative metering with no exposure compensation, ISO 100 @ f/5.6. Note the variation in shutter speed the camera chooses for each image.


All targets.


Black sweatshirt.


White T-shirt


18% grey card.

Ian

Thanks for this....

Okaaaayy..... so if a scene has something almost black in it and something almost white, then as long as there is something also in the pic that equates to around 18% grey, then the black and white areas will expose correctly?

WPuld this be for evaluative as well as partial ( centre weighted) metering?

 

[letsgofishing]

R2D2 wrote:

letsgofishing wrote:

you are also saying that the evaluative metering on the camera does not represent the scene as it is in reality?

Exactly. It tries harder, but it can't.

It will average any scene to 18% grey no matter what the actual liighting conditions are?

Nope. Evaluative metering often results in exposures that can be far from that.

In fact the T4i throws another wrench into things by using what Canon calls its 63-zone iFCL (intelligent Focus, Color, Luminance) metering system, which takes focus, color, illumination, and data from all 9 AF points into account when determining exposure.

NOW try to guess how the camera is going to expose your scene. Yikes.

Fortunately there are still the other metering modes (spot, partial, & center-weighted), where your exposure meter will turn whatever fills the metering area into 18% grey. Combine that fact with the samples that Ian posted and you are well on your way.

Happy shooting,

R2

ps. Don't worry, we aren't tiring of this discussion . This is what we LIVE FOR!!!

Appreciated R2!

 

[letsgofishing]

Thanks for all the replies - much appreciated!

Going to order "Understanding Exposure" by Brian Petersen"

 

[WilbaW]

letsgofishing wrote:

Okaaaayy..... so if a scene has something almost black in it and something almost white, then as long as there is something also in the pic that equates to around 18% grey, then the black and white areas will expose correctly?

Not necessarily. If the meter only sees the grey you would expect it to be okay, but only if the scene were evenly illuminated. If the grey were in shadow and the rest in sunlight, or the other way around, you won't get a "correct exposure". So you have to approach it differently. See Metering and Exposure in the unofficial Rebel Talk FAQ.

WPuld this be for evaluative as well as partial ( centre weighted) metering?

The meter just gives you a guess to get you going, so it doesn't matter much where you start from as long as you protect your highlights. Many prefer centre-weighted average for its consistency, but that's under discussion in other threads. (Partial and CWA are distinct modes with different scopes, BTW.)