Go Back   Steve's Digicams Forums > Digicam Help > What Camera Should I Buy?

Reply
 
Thread Tools Search this Thread
Old May 8, 2005, 10:02 PM   #1
Member
 
Join Date: Apr 2005
Posts: 69
Default

ive read in a couple of posts about "dslr vs prosumer compact" that getting portriat-style, short DOF shots with fixed lens compacts is difficult do to their using small CCD's and short actual focal length (verses their 35mm equivelant.) my question is this: even some DSLR models (most of the less expensive ones, it seems) also use small chips and thus use lower actual focal length lenses than their 35mm equivelent. will they have the same trouble getting these portrait style, short DOF shots as well?

i'm concerned about this because coming from a 35mm SLR background, i like to be able to vary the DOF in my shots, but if shooting at 80mm f/3.5 on a digital isnt going to look the same as it would on a 35mm, i am worried.

anybody that can shed some light on this issue? i wonder why reviews never seem to mention this...
turkish a. punkass is offline   Reply With Quote
Sponsored Links
Old May 8, 2005, 10:44 PM   #2
Senior Member
 
Join Date: Jul 2003
Posts: 3,396
Default

Check the online depth of field tool at http://www.dofmaster.com/dofjs.html :-)

The depth of field is a product of the real focal length, and the F-stop used. The different sized sensors give the different crop factors AKA: The effective focal length.

In many of the P&S cameras the real focal length can be about 5.8mm-24mm(in the case of my old nilkon 5400) and with a 1/1.8 sensor that equates to about 28-116MM in 35mm equivelance. But for DOF you are working with a 5.8-24mm lens :-) So you always end up with a big DOF.

With my EOS 20D(1.6 crop) and a 300mm lens at F2.8 the DOF is measured in inches, just the same as it would be on a 35mm camera. Similar DOF, but the crop factor makes it look like a 480mm lens.

Your 80mm F3.5 would give you the same DOF on a DSLR as it does on a 35mm, but on a Canon EOS rebelXT or 20D it would appear to be a 128mm lens.

Hope this helps :-)
Peter.
PeterP is offline   Reply With Quote
Old May 9, 2005, 12:23 AM   #3
Member
 
Join Date: Apr 2005
Posts: 69
Default

well that certainly sucks. so getting a short DOF shot with something like a Casio Exilim P-700 would pretty much seem to be impossible. this is dissapointing, to say the least.
turkish a. punkass is offline   Reply With Quote
Old May 9, 2005, 1:12 AM   #4
Senior Member
 
Join Date: Jul 2003
Posts: 3,396
Default

No, while the big DOF is an annoying "feature" of P&S cameras :-) , actually it is physics.

Peter.
PeterP is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 2:09 AM.