Over exposing white question

[amid chaos]

I am relatively new to my 20D.
How do I take this picture without over exposing the white? thank you.

Camera model: Canon EOS 20D
Date/Time: 2006:03:24 01:54:00
Resolution: 438 x 292
Flash used: No
Focal length: 31.0mm (35mm equivalent: 50mm)
CCD width: 22.48mm
Exposure time: 0.0040 s (1/250)
Aperture: f/29.0
ISO equiv.: 1600
Whitebalance: Auto
Metering Mode: matrix
Exposure: aperture priority (semi-auto)

 

[MICKEY88]

first I need to ask, why in the world are you shooting at 1600 iso....

drop to 100 iso for a sharper pic.... that alone might help if not, use a faster shutter speed to give less exposure..

 

[Kelly Grannell]

he wants to use f/29.

Regardless, Mickey88 is correct. At ISO1600 you're using 1/250 shutter speed while you're only using 50mm equivalent. So the maximum you should use is ISO 400 so you can have about 1/60 shutter speed. Besides, don't use f/29, it will never be sharp. The max you should use is around f/22.

In terms of getting the white real white, use spot metering on the white and take the shot.

 

[MICKEY88]

another tthought, if you are using f29 for max depth of field, f16 should actually do the trick, however you must focus on the front of the flowers..

if you focus on the center, the flowers closer to you will not be sharp, when talking depth of field it's usually from your focus point and farther,,,

so shallow depth of field may be from your focus point to 1 foot beyond, whereas a really deep depth of field may be from your focus point to infinity....

but you can't change the depth of field from your focus point forward...

 

[boBQuincy]

Check the histogram, if it shows a spike at the far right the image is overexposed.
On a high contrast scene you can extend your range by bracketing and merging the images later (as long as you used a tripod so the camera did not move between images).

Leave the histogram on, it gives a lot of information about the exposure.


boB

 

[PaulD]

Using a high ISO will decrease your dynamic range. You should attempt to keep your ISO as low as possible and expose to the left. What I mean by that is to check your histogram and to make sure that your highlights haven't blown themselves off the right hand side of the graph. If they have and there are blinking highlights (you have this turned on with your image review right?) then reduce your exposure and take the shot again.

You can shoot in RAW and recover some highlight detail but that's a whole other story. But it's not magic and you still need a good exposure.

Also, as far as depth of field is concerned you need to keep in mind that 1/3 of "acceptable" focus is in front of the focus point (toward the camera) and 2/3 falls behind. Until you reach the hyper-focal distance where the depth of field extends out to infinity. This stuff is not as easy to determine now as it was in the past when lenses had this information printed right on the ring. Just remember that you should focus about 1/3 of the way into the area that you want to be in acceptable focus.