Jump to content


Photo

relay lenses


  • Please log in to reply
8 replies to this topic

#1 Daniel Madsen

Daniel Madsen
  • Basic Members
  • PipPipPip
  • 201 posts
  • Student
  • Boston

Posted 10 March 2007 - 02:37 PM

What is a relay lense? That is all.
  • 0

#2 chuck colburn

chuck colburn
  • Basic Members
  • PipPipPipPip
  • 389 posts
  • Other
  • orygun

Posted 10 March 2007 - 03:29 PM

What is a relay lense? That is all.


Hi Danielle,

Most times, relay optics are used to move the image a given distance without changing the size of the original.

Chuck
  • 0

#3 Daniel Madsen

Daniel Madsen
  • Basic Members
  • PipPipPip
  • 201 posts
  • Student
  • Boston

Posted 10 March 2007 - 07:02 PM

and why would you use such a thing?
  • 0

#4 Mike Rizos

Mike Rizos
  • Basic Members
  • PipPipPipPip
  • 330 posts
  • Other

Posted 10 March 2007 - 07:25 PM

A viewfinder extension uses them.
  • 0

#5 Phil Rhodes

Phil Rhodes
  • Sustaining Members
  • 11944 posts
  • Other

Posted 10 March 2007 - 07:34 PM

A lense is a spelling mistake.

A lens is a piece of optical equipment.

Phil
  • 0

#6 chuck colburn

chuck colburn
  • Basic Members
  • PipPipPipPip
  • 389 posts
  • Other
  • orygun

Posted 10 March 2007 - 09:43 PM

A lense is a spelling mistake.

A lens is a piece of optical equipment.

Phil


Jeeeeze Phil,

Picky picky picky LOL
And if you want to get right down to it, a lens is a component of a given piece of optical equipment.

Chuck
  • 0

#7 Rob van Gelder

Rob van Gelder
  • Basic Members
  • PipPipPip
  • 158 posts
  • Steadicam Operator
  • Bangkok, Thailand

Posted 11 March 2007 - 09:13 AM

instead of picky remarks or correct but vague descriptions........

A relay lens is often used in snorkel lenses or boroscope and periscope and endoscope lenses (assemblies ;-) )

It brings the image further away from the first focal plane, normally with a 1:1 transfer ratio.
That way, you can make lenses that can fit is small holes/tubes/cavities or have wide angle macro lenses with an extension tube (relay lens) that brings the camera further away from the object, so you have less shadow and a better chance to light the subject.
  • 0

#8 chuck colburn

chuck colburn
  • Basic Members
  • PipPipPipPip
  • 389 posts
  • Other
  • orygun

Posted 11 March 2007 - 09:30 AM

What Rob said.
Oh yeah and everybodys favorite, the proctoscope! OUCH
  • 0

#9 Rob van Gelder

Rob van Gelder
  • Basic Members
  • PipPipPip
  • 158 posts
  • Steadicam Operator
  • Bangkok, Thailand

Posted 12 March 2007 - 12:23 AM

i didn't go into detail about the "cavities" :D

Oh, one important thing to remember: relais lenses loose a lot of light when moving the image further.
3 to 5 stops is not unusual and so you can have a 2.8 lens on the front but still an effective opening of 8 or 11.
And then they are not even on their best in optical performance, stop down (on the relay lens, not the front lens!) to 22 to 45 for best results.

Oh, let's not forget that many of the older systems need to be completely clean or you will see every speck of dust on your final image.

nightmares.......... :blink:
  • 0


rebotnix Technologies

Tai Audio

Metropolis Post

Abel Cine

Wooden Camera

Broadcast Solutions Inc

CineLab

Rig Wheels Passport

Media Blackout - Custom Cables and AKS

Opal

The Slider

Glidecam

Visual Products

Aerial Filmworks

Willys Widgets

FJS International, LLC

Technodolly

Paralinx LLC

Gamma Ray Digital Inc

Ritter Battery

CineTape

Media Blackout - Custom Cables and AKS

Wooden Camera

rebotnix Technologies

Ritter Battery

Metropolis Post

Willys Widgets

Rig Wheels Passport

Gamma Ray Digital Inc

Glidecam

Visual Products

CineLab

FJS International, LLC

Opal

Tai Audio

CineTape

Aerial Filmworks

Technodolly

The Slider

Paralinx LLC

Abel Cine

Broadcast Solutions Inc