How exactly does over/under exposure do?

[lorenzo23]

Thank you all for your replies.
I mentioned Manual mode in my first post as an example, I wanted to know actually which parameters change when changing EC in each mode. You have definitely cleared my doubts.

I have a Canon 60D, should have mentioned that earlier

[davidedric]

That means you were using a Canon DSLR in Manual Mode, with AUTO ISO engaged.

The display was working correctly, as Dave has mentioned.

Sorry, it was late at night and I only told half the story. You are quite right of course that everything is working correctly. The missing bit is that the 600D is a "single dial" camera, and in manual mode the dial operates the shutter speed. The button that you press to make it operate the aperture is the Av +/- button which in other modes is where you dial in exposure compensation. So, yes you can't dial in exposure compensation in manual mode, but when you reduce the aperture to the point where you are up against the set ISO limit, you effectively start to dial in under-exposure, and the "meter" reflects this.

Not a major point, I just posted this addition so that I hope I don't look like a complete idiot

Dave

[William W]

Dave, I understood the point you were making - be assured it was NOT an idiotic point - it was quite realistic to ask at the time when you first saw it "what is this crazy thing that is happening?"

I have seen similar confusion when Auto ISO first was released, I was working with a guy using a new Nikon and it really threw him sideways.

Further to the point of Canon Cameras, it doesn't matter what model Canon Camera it is - there are not enough dials on any of them, to allow Exposure Compensation to be activated when the camera is Manual Mode and Auto ISO is activated: that was the main the reason for my comment. All Canon Cameras' Exposure meter's LED displays, will do what your 600D did, when they run out of AUTO ISO.

WW

[Dave Humphries]

In your and my Nikon cameras, there are two displays -- the exposure meter and the exposure compensation -- and they need to be used concurrently. The exposure meter never displays exposure compensation; it always displays the exposure regardless of what method is being used to achieve it. The purpose of each display never changes.

As an example, the exposure meter may be showing one stop over exposed and the exposure compensation display may display zero compensation. If you then use the exposure compensation to reduce exposure by one stop, its display will indicate that you have done that. The exposure meter will then indicate that the exposure is neither under nor over exposed.

My point is that the exposure meter displays the exposure and the exposure compensation displays whether in fact exposure compensation is being used to achieve the exposure.

Hi Mike,

At the risk of hijacking Lorenzo's thread, I'd like to clarify things,

I don't have two separate 'scales' on my D7100, just the one; so it is dual purpose*.
There is an icon that is illuminated when any amount of EC is set, including in Manual mode, but it only shows which direction EC is applied (+ or -).

I shot this weekend in Manual mode with Fixed ISO much of the time.
In use, the meter is what is on the scale - unless I press and hold the +/- (EC) button down.

When moving from say Aperture Priority to Manual, whatever EC was last used in Aperture Priority is what is used as the meter offset in Manual mode.

* I cannot recall what camera you have Mike, but if a D7100, there is something in my set up makes it display different things to yours; if I press and hold the +/- (EC) button, there are a set of numeric figures that appear over on the right hand side, but I have this area displaying ISO by default, which is what I guess also makes my linear scale dual purpose.

I do agree with the effects of what you say in the second paragraph above.

[Mike Buckley]

Interesting, Dave. I'm using a D7000. Your D7100 is one generation later than my D7000 so I assumed your viewfinder displays at least everything mine does.

When I press and hold the EC button, the numeric EC value is displayed on the right side. When I release the button, the ISO value is displayed there. At all times, the exposure meter is displayed in the middle. I'm not understanding your details about that. Are they different?