Calculating DOF for HD
Posted 26 November 2007 - 02:55 PM
Posted 26 November 2007 - 05:20 PM
Posted 26 November 2007 - 05:55 PM
16mm isn't exactly close. 2/3" video uses an image area between the size of Super-8 and 16mm, you could split the difference. The closest film format would be 9.5mm.
Thanks for your reply. I'm wondering if that is the whole story though... When comparing film formats (Super 8, 16mm, 35mm), the size of the negative obviously affects resolution and therefore apparent DOF. The same would be true comparing 1/3" video chips to 2/3" chips. However, when comparing HD video resolution captured on 2/3" chips to SD video resolution also captured on 2/3" chips, the difference in DOF is significant. So there are more factors affecting DOF in video formats than just sensor size. Therefore, can we just compare "image target" size when comparing DOF between film and video formats? Of course viewing format (TV monitor, projection, etc.) is also a factor in determining "apparent DOF."
My project is a commercial (shot on a Varicam) to be broadcast on SD television. But to be safe, I always evaluate my image (focus, etc.) on at least a 720p high def monitor. I've never attempted a side by side comparison, but my experience has been that 720p HD "feels" like it has DOF similar to 16mm. But if anyone has tested this more accurately, I would love to know.