Dimage 7i DOF at High Shutter Speeds

08/16/2004 06:40:27 PM · #1

I have been enjoying the learning curve with photography and have spent several enjoyable hours taking loads of macro pics with the Dimage 7i.
However if I am trying to use the higher shutter speeds (1/750 and above) it seems to limit me to F3.5

This is really limiting as the DOF seems REALLY tight.
QUESTION: Is there any way of expanding this, even slightly?

Below (i hope) is an effort from this weekend which could have looked a lot better if I could even stretch a few mm more into focus:
[thumb]//www.dpchallenge.com/image.php?IMAGE_ID=97824[/thumb]

Konador

Canon EOS-500D Rebel T1i

08/16/2004 06:43:14 PM · #2

This is because the lower f-numbers let more light in to the camera, so to avoid underexposing the shot, the camera needs to lower it to let enough light in at 1/750. I'm not sure if you can on that camera, but try turning the ISO up, or see if there is a full manual mode where you set it all manually. You might get underexposed shots but they can be saved to a certain extent on photoshop, whereas you can't sharped an OOF background :)

08/16/2004 06:53:58 PM · #3

Thanks Konador. The shot of the fly (sorry the thumbnail didn't work...) was with almost all settings at manual (including focus), however the ISO was on auto which set it at 100. I'll be sure to try upping the ISO the moment the rain lets up.... which hopefully will be this year. - Dublin Ireland

Canon EF 28-135mm F/3.5-5.6 IS USM

08/16/2004 06:56:12 PM · #4

Ok, so that's the first time I've got a thumbnail right...

GoodEnd

Canon EOS-350D Rebel XT

08/16/2004 07:02:46 PM · #5

Some Compact cameras has this issue to protect you from "break the rules". Apperture are a physic relation to the lens in use, in some cameras that have only one lens, to inprove the shutter speed the designers used the electronic shutter mixed up or not with a mechanical one. That is why some cameras has to restrict some appertures at certain speeds. Mine CP5700 do it at 1/4000, limiting me to minumum f3.5 regardless of my focal lenght.

That is why I want a DSLR...