Beginner Main Dial Pointer

[funny_h0w]

Hello, sorry if this is posted in the wrong place. My friend was telling me the other day how to change the exposure settings on the camera using the Main Dial on the Canon 100D.

He said I should half press the shutter and look at the screen and adjust the dial as needed.

I have been experimenting with it all I can see is that is 'brightens/darkens' the image. Am I using it wrong?

It is the -3 to 3 seconds (lowest bit of the image). I believe it is called the exposure compensation.

 

[StewartR]

Am I using it wrong?

That depends on what you're trying to achieve. I'm not quite sure whether you want to change the exposure settings or change the exposure.

The main dial does different things depending on what mode the camera is in and what button, if any, you're pressing at the same time.

In Tv (shutter priority) mode it alters the shutter speed. In Av (aperture priority) mode it alters the aperture. in P mode it shifts the program, eg 1/400th@f/4 -> 1/200th@f/5.6 -> 1/100th@f/8. These affect the exposure settings - in the sense that 1/400th@f/4 is a different setting from 1/100th@f/8 - but they don't affect the actual exposure in the sense of making the picture lighter or darker because these modes are all automatic or semi-automatic. In these modes, if you adjust the shutter speed the camera will adjust the aperture, and vice versa, to maintain the same exposure.

In M (manual) mode, the main dial alters the shutter speed, or if you hold down the Av+/- button at the same time it alters the aperture. Both these changes do affect the exposure - make the picture brighter or darker - because in manual mode the camera does not adjust any settings.

Exposure compensation (EC) is a way of affecting the exposure without using M mode. In Av or Tv mode, hold down the Av+/- button and rotate the main dial. This increases or decreases the exposure. In Tv mode it leaves the shutter speed as you set it, and changes the aperture to be greater or less than it would otherwise have been if you hadn't used EC. Similarly, in Av mode it leaves the aperture as you set it, and changes the shutter speed to be faster or slower than it would otherwise have been if you hadn't used EC.

Does that answer your question?

 

[sirch]

all I can see is that is 'brightens/darkens' the image

Yes, that's what it does but I am curious as to what you were expecting? "Exposure" is essentially making the image brighter or darker or ideally making it the correct brightness so that the highlights are not blown out and there is still some detail in the shadows although getting these two extremes correct is not always possible by just changing the camera settings.

The you have 3 things to adjust that control exposure: aperture, shutter speed and ISO. The point to understand is why you would change one or another, Changing aperture affects depth-of-field, changing shutter speed affects whether things that are moving appear sharp or blurred and changing ISO can affect things like noise in your image.

 

[funny_h0w]

Yes, that's what it does but I am curious as to what you were expecting? "Exposure" is essentially making the image brighter or darker or ideally making it the correct brightness so that the highlights are not blown out and there is still some detail in the shadows although getting these two extremes correct is not always possible by just changing the camera settings.

Sorry I didn't explain myself very well, it was when I am in Manual Mode and I press the s***ter speed half down, I can adjust the exposure using the -3 to 3 dial on the screen. My friend never explained what the dial did with the rest of the settings .

The you have 3 things to adjust that control exposure: aperture, shutter speed and ISO. The point to understand is why you would change one or another, Changing aperture affects depth-of-field, changing shutter speed affects whether things that are moving appear sharp or blurred and changing ISO can affect things like noise in your image.

This is something I am trying to practice at the moment when I'm out and about. Some photos are good, some bad...

[QUOTE="StewartR, post: 7105280, member: 3821"

Exposure compensation (EC) is a way of affecting the exposure without using M mode. In Av or Tv mode, hold down the Av+/- button and rotate the main dial. This increases or decreases the exposure. In Tv mode it leaves the shutter speed as you set it, and changes the aperture to be greater or less than it would otherwise have been if you hadn't used EC. Similarly, in Av mode it leaves the aperture as you set it, and changes the shutter speed to be faster or slower than it would otherwise have been if you hadn't used EC.

Does that answer your question?[/QUOTE]

Yes, this has given me a very detailed answer, thank you. .

 

[omens]

I had a look at the manual for the 100D. It confirms the above - the "main pointer" (ie the arrows) will appear alongside whatever is adjustable at the point. If you're in Aperture mode, you can either adjust aperture or exposure compensation. If you're in Shutter mode, you can adjust shutter speed or exposure compensation. If you're in manual, you can adjust both shutter and aperture.

I'd advise you to read the manual: http://www.canon.co.uk/support/cons...ital_slr/eos_100d.aspx?type=manuals&language=
or buy a book that explains things in much more detail eg http://www.amazon.co.uk/David-Buschs-Compact-Field-Guides/dp/1285866320
or http://www.amazon.co.uk/Canon-Rebel-100D-Expanded-Guide/dp/1781450560

 

[funny_h0w]

Thank you for this. I did read the manual but got a bit confused. Confusion over now though haha. Thank you.