[quote name='Rover' timestamp='1322475720' post='13299']
I had the same thought...
Correct me if I'm wrong but the DOF has nothing to do with image format, it only gets bigger because a lens of less focal length is used for the same framing and / or the subject to camera distance increases. Guess many people confuse using crop cameras with using TCs (say a 2x, which doubles the actual FL but halves the actual aperture - both wrt DOF AND wrt light collected). But unless I am mistaken, using the same lens at the same FL and subject to camera distance, then cropping the image for the same FOV yields the same image (except sensor-specific level of noise, etc.)
The "equivalent aperture" notion surely is misleading, especially at first. As if equivalent focal length wasn't enough. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' /> I was always confused why many people spin it so much. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='
' />
[/quote]
Your explanation is correct but, sorry, your argument is certainly not.
You compare formats based on the same field-of-view. It is absolutely irrelevant from a user perspective that the DOF is the same on Q and a FF DSLR if you crop FF image down to the same crop format like Q. That's not a use-case for a single person on mother Earth.
Here's your FF DSLR, here's your Q. Same distance, same field-of-view, same aperture. Now what's the depth-of-field ?
There is NOTHING here that can be remotely misleading in this approach.
If so you could also argue that the equivalent focal length is just as misleading yet nobody seems to have an issue with this.
I had the same thought...
Correct me if I'm wrong but the DOF has nothing to do with image format, it only gets bigger because a lens of less focal length is used for the same framing and / or the subject to camera distance increases. Guess many people confuse using crop cameras with using TCs (say a 2x, which doubles the actual FL but halves the actual aperture - both wrt DOF AND wrt light collected). But unless I am mistaken, using the same lens at the same FL and subject to camera distance, then cropping the image for the same FOV yields the same image (except sensor-specific level of noise, etc.)
The "equivalent aperture" notion surely is misleading, especially at first. As if equivalent focal length wasn't enough. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' /> I was always confused why many people spin it so much. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/smile.gif' class='bbc_emoticon' alt='' />[/quote]
Your explanation is correct but, sorry, your argument is certainly not.
You compare formats based on the same field-of-view. It is absolutely irrelevant from a user perspective that the DOF is the same on Q and a FF DSLR if you crop FF image down to the same crop format like Q. That's not a use-case for a single person on mother Earth.
Here's your FF DSLR, here's your Q. Same distance, same field-of-view, same aperture. Now what's the depth-of-field ?
There is NOTHING here that can be remotely misleading in this approach.
If so you could also argue that the equivalent focal length is just as misleading yet nobody seems to have an issue with this.