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Photography Question 
Chris London
 

Depth of Field with Digital and Multipliers


When using a longer lens, the depth of field for a particular aperature is shallower than when you use a shorter lens. When using a digital SLR camera with a multiplication factor (normally 1.5 or 1.6), does this in turn give a DOF (compression) similar to the original lens length or the adjusted/multiplied length? I assume it would be as per the original length, but would like to know for sure.

Thanks!


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12/28/2003 11:13:14 AM

 
Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
gregorylagrange.org
  No it dosen't. Many people call it a telephoto effect when contrasting digital with film cameras, but that's not really what it is. It's just a cropping effect. The perspective and the compression you get from telephoto lenses are the same. It's just that you get a narrower view with digital because the film area is smaller.


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12/28/2003 2:19:04 PM

 
Chris London   Thanks Gregory. That's what I suspected, but glad to know for sure.

The knowledge I will be moving into the digital SLR world very soon is impacting my lens decisions and I want to keep on top of it to make the right choices.

Thanks!


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12/28/2003 8:09:05 PM

 
Hector Reinoso   actually it does. There was a great article by Bob Atkis on www.photo.net about it. (dont have the link, so do a search).

But basically means that when using hyperfocal for example, you need to setup the aperture 1 1/3 smaller than you would for any given hyperfocal distance.

The same results can be seen when using any online or table for depth of field calculation, like DOF master.

hope it helps,


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12/30/2003 2:55:23 PM

 
Gregory LaGrange
BetterPhoto Member Since: 11/11/2003
gregorylagrange.org
  He's talking about digital slr's that have a ccd smaller than a normal 35mm film area. If you have a film camera and you have somebody standing so that the top of their head is at the top of the frame with something like a 400mm, if you put that same lens on something like a D60, you'll get the same view as you would if you had a 620 on the film camera. Which means back up,raise the camera up, or you'll cut their head off.
Putting the same lens on a digital slr isn't going to change depth of field, it's just going to cut off the edges of what you would normally see on a film camera.


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12/30/2003 5:24:36 PM

 
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