Jump to content


Photo

can diopters far and close focus charts be generalized for the same focal lenght but different sets of lenses?

diopters charts

  • Please log in to reply
1 reply to this topic

#1 davide sorasio

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

Posted 18 July 2017 - 03:40 PM

Hello everyone, maybe this is a silly question but it has been in my head for a while.

Once I have a close and far focus chart for a certain focal lenght, could it be used for the same focal lenght of another set of lenses that have the same T-stop when wide open? For example, shooting at the same settings on the same camera with a 75mm Master prime using a diopter +1 would give me the same far and close focus if switching to another lens with the same wide open T stop?

and if not, which are the factors that influence close and far focus on diopters except from the diopter's gradation?

Thanks in advance


  • 0

#2 Kar Wai Ng

Kar Wai Ng
  • Basic Members
  • PipPipPip
  • 127 posts
  • 1st Assistant Camera
  • Toronto, Canada

Posted 19 July 2017 - 02:06 AM

If the other lens is a 75mm Master Prime, then you would have the same near and far focus point; with another make of lens like a Cooke 75mm, however, you would have slightly different results because the entrance pupil is different. I don't think it would be dramatically different. A +1 diopter would still put your infinity at 1 meter in front of the diopter, theoretically.


  • 0



Paralinx LLC

New Pro Video - New and Used Equipment

FJS International, LLC

CineTape

Media Blackout - Custom Cables and AKS

Broadcast Solutions Inc

Willys Widgets

Glidecam

Ritter Battery

Aerial Filmworks

CineLab

Metropolis Post

Abel Cine

The Slider

Gamma Ray Digital Inc

Rig Wheels Passport

Visual Products

Technodolly

rebotnix Technologies

Tai Audio

Wooden Camera

Rig Wheels Passport

Broadcast Solutions Inc

New Pro Video - New and Used Equipment

CineLab

Metropolis Post

Media Blackout - Custom Cables and AKS

Abel Cine

Wooden Camera

Visual Products

The Slider

rebotnix Technologies

Paralinx LLC

Gamma Ray Digital Inc

CineTape

Technodolly

Glidecam

Aerial Filmworks

Tai Audio

FJS International, LLC

Willys Widgets

Ritter Battery