Jump to content




Photo

Does the resolution effect depth of field

depth of field resolution sensor

  • Please log in to reply
2 replies to this topic

#1 davide sorasio

davide sorasio
  • Basic Members
  • PipPip
  • 89 posts
  • Student
  • New York

Posted 27 April 2016 - 06:11 PM

Hi everybody, I apologize in adavence if the question is silly but: I know that the bigger the sensor the shallower the depth of field is, but does that translate in digital related to the resolution of the camera?

To be clearer, on the same camera, for example an alexa super 35mm cmos sensor, shooting 3.2k or 2k or standard HD is it gonna effect the depth of field?

Thanks for the help!

 


  • 0




#2 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 18788 posts
  • Cinematographer
  • Los Angeles

Posted 27 April 2016 - 06:40 PM

At best, all I can say is "sort of" -- a major component of the depth of field calculation is the Circle of Confusion, a rightly named concept, based loosely on the idea of how far can the focus be out before point become a noticeable circle instead, or in other words, what is the focus range around the correct focus distance where a point still looks like a point and not a fuzzy circle.  And that Circle of Confusion figure is based on the degree of image magnification, another fuzzy concept since we see images at all sorts of distances to the screen or monitor.  But we have to pick a figure in order to make the calculations.

 

So logically you figure that the more resolution that the image and display together have, the more clearly you'd see whether a point was in focus or not.

 

Another issue is edge contrast and how quickly or gradually detail falls out of focus, digital tends to have a more "abrupt" transition from sharp to soft which makes the image seem like it has less depth of field.

 

All this to say that traditional depth of field charts work on assumptions regarding the degree of enlargement and the Circle of Confusion figure chosen that may or may not be correct today.


  • 0

#3 Mark Dunn

Mark Dunn
  • Basic Members
  • PipPipPipPip
  • 2182 posts
  • Other
  • London

Posted 28 April 2016 - 03:56 AM

OP, the word you mean to use is 'affect'. 'Effect' as a verb means "to carry out", not "to have an influence on".


Edited by Mark Dunn, 28 April 2016 - 03:56 AM.

  • 0



The Slider

Abel Cine

Rig Wheels Passport

Tai Audio

Media Blackout - Custom Cables and AKS

Pro 8mm

Paralinx LLC

Willys Widgets

Technodolly

Glidecam

Ritter Battery

rebotnix Technologies

Aerial Filmworks

CineLab

Zylight

CineTape

Visual Products

Broadcast Solutions Inc

Aerial Filmworks

The Slider

Abel Cine

Willys Widgets

Broadcast Solutions Inc

Zylight

Ritter Battery

CineTape

Visual Products

Technodolly

Pro 8mm

CineLab

Tai Audio

Media Blackout - Custom Cables and AKS

Glidecam

Paralinx LLC

rebotnix Technologies

Rig Wheels Passport