Digital Camera Dilemma - Depth of field

[Anne Kilmer]

Clay Taylor wrote:
> 
> All -
> 
>     Kenelm is absolutely right, but note that in his example that the image
> of the subject taken through the shorter focal length / faster lens (the 2
> inch f/2.0) must be MAGNIFIED (in this case 2x) to the same size as the 4"
> lens image to find that the Depths-of-field are in fact identical.   Had
> that example used the 2" lens at f/4 (to match the f-stop of the 4" lens)
> and then magnified the image 2x, the depth of field would have been GREATER.
> Excellent, right?
> 
>     The problem here (especially with digital cameras) is that you are using
> less pixels to cover the subject, and when the image is enlarged to a
> workable size, the image quality suffers - you are in effect doing the
> "digital zoom" that is such a horrible marketing gimmick in the camcorder
> and digital-still camera  world.
> 
> Clay Taylor
> Moodus, CT
Yes, that digital zoom is a horrible thing ... and I have to watch
carefully when I go zooming around, as I certainly don't want to do the
digital thing. I can, after all, just enlarge the image when I want to
see it bigger ... I just make sure I shoot at high resolition. 
What I find that I am not doing is holding the furshlugginer camera
still. I am going to go shopping and investigate copy stands, thingies
to hold slides while I copy them, stuff like that. For the Nikon
Coolpix, natch. A scanner does not require a steady hand; you can drink
heavily and still scan just fine. 
I am even toying with the thought of getting out the tripod, which is
ridiculous. You can't shoot bugs from a tripod. I dont' think you can
even shoot grandchildren from a tripod unless you chill them down in the
fridge first. And then the beer will be all warm. 
As for depth of field, I used to understand it, but I have spent many
happy years not caring, and this comes as rather a shock to me. You mean
I have to pay attention and think about what I'm doing? But ... I am an
American. I thought we were excused. 
Anne Kilmer
South Florida ... is it OK if I quit praying for rain now?

 
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