Weird question regarding camera getting it very wrong

[Squidy]

Hi all,

Canon 6D, Canon 24-105mm F4

I have a bit of a weird question. On the weekend my fiance and I went to some old settler's village here in Sydney, Australia to shoot some photos. I usually use my camera on auto ISO when using TV or AV mode. I was shooting an old abandoned house with a stormy sky behind it. It wasn't dark that day, just overcast a bit. The weird thing is when I went to focus on the house I was on F4.0 as I was using my 24-105mm. When I focused on the house it went to 100 ISO and 1/4000 shutter speed. Needless to say the photos looked very, very dark. I tried a few shots and the same thing happened. I went changed the ISO to 800 and the shutter speed still went to 1/4000. I turned around to take a photo of the orchards under the same sky and the camera functioned perfectly on auto ISO, but back again towards the house and it went out of whack again.

I was able to get some good shots when I switched to manual and made all the settings myself (4.0, 125ms, ISO 800) but in auto ISO and even with the camera on 800 ISO it still went to some incredibly fast shutter speed and made the whole photo look pitch black.

I also turned off auto lighting optimiser but still no luck.

Any ideas what could cause this? I'm happy to shoot in manual for this kind of thing if I can but I was hoping to be able to use AV mode especially if I'm in a hurry (ie with a fiance getting bored pretty quickly.

[HDNitehawk]

My first guess is metering and how you set it up.
Most likely the camera was metering off of the background sky not the building.
If that is the case though once you shot the building correctly your background sky or some part of the picture should be completely blown out.

Edit: My guess is you are using Evaluative or Center Weighted.

[Dave Throgmartin]

I personally like center weighted, but it's necessary to watch the histogram like you did.

Can you post the image?

Dave

[Squidy]

I'll load it up into Lightroom at work and upload it.

What kind of metering should I use in these instances? I think it was evaluative

[Squidy]

Oh, and I wasn't watching the histogram, I still don't know how to read it properly

[HDNitehawk]

Spot maybe in that one instance. But there is no right answer, only that you know what the camera is doing and pick the one that works for you.
I keep mine on spot metering because it suits me. But that might give me the opposite problem in that if I do not pay attention it blows out the background.
I know this so if I am shooting landscape I stick with manual mode, meter the background with spot and meter the subject then decide what exposure I want.
Evaluative is supposed to sort that out for you.

[Dave Throgmartin]

Oh, and I wasn't watching the histogram, I still don't know how to read it properly

re: histogram

http://www.bhphotovideo.com/explora/...eras-histogram

I prefer center weighted because it is predictable. Evaluate uses an algorithm to try and predict what the proper exposure is. If what I'm getting doesn't match my expectations I dial in EV compensation or put in manual mode.

Dave

[Squidy]

http://i.imgur.com/o44n28u.jpg

This is the image, it's F4.0, ISO 100 (selected by auto iso) and 1/4000

And apologies about the watermark, I forgot to turn that feature off

[Kayaker72]

Sky is exposed properly and is the majority of the frame. My guess is evaluative and it grabbed the sky.

https://photographersconnection.com/...etering-modes/

Btw, one of the features I am hoping flows down from the 1d series to the 5D IV is exposure tracking to the AF point.

[Dave Throgmartin]

That's a really tough scene. This one might beg for HDR - the shot you have here exposed for the sky and another with the house/ground exposed properly.

As is, for this image to work out it would appear to require a significant brightening of the house/ground.

Dave