What is a rangefinder? - DPChallenge Forums

Leica 35mm f/1.4 Summilux M Aspherical MF - Black

03/04/2010 09:20:32 AM · #1

I watch the auction sites once in awhile and I'll see "Rangefinder" cameras listed. They look cool. What classifies them as a rangefinder? I've been shooting 35mm film since the late 80's, but used a standard Pentax SLR back then, and didn't really pay attention to equipment outside of my small kit (camera and 2 lens).

Guess I could google it, but it's more fun to ask. :-)

scarbrd

Leica M10

03/04/2010 09:28:29 AM · #2

A rangefinder camera is different from an SLR in that it does not have a mirror box and a pentaprism to bring the reflected image correctly into the eye piece that you look through.

SLRs give you "Through the lens" viewing, rangefinders do not. You look through a window in the camera body. The focusing is done via a smaller window within the view window. The smaller window has the portion of the image that lines up with the main window to focus the lens.

Decent Wikipedia article

Leica still makes rangefinder cameras, very expensive ones.

The most famous of which, and arguably, the finest mechanical camera ever made is the Leica M3.

Message edited by author 2010-03-04 09:29:32.

Yo_Spiff

Olympus OM-D E-M5 Mark III

Olympus 12-100mm f/4.0 M.Zuiko ED IS PRO

03/04/2010 09:54:08 AM · #3

I think what classifies them as a rangefinder is the focusing method. For instance, the popular Argus "brick"

Notice there are 2 viewfinders on the front. You will see in the single viewfinder on the back, a split image. To focus, you identify what you want in focus and adjust the focus wheel so that the images are matched up. It "finds the range", I suppose.

BTW, the focusing system on these Argus bricks are great for building muscular fingers.

Message edited by author 2010-03-04 10:08:57.

Olympus OM-D E-M5 Mark III

03/04/2010 10:05:18 AM · #4

Originally posted by Yo_Spiff:

... BTW, the focusing system on these Argus bricks are great for building muscular fingers.

And eyestrain for those with aging eyesight! :-)

Thanks for the feedback guys, and for the link David.

Yo_Spiff

Olympus 12-100mm f/4.0 M.Zuiko ED IS PRO

03/04/2010 10:11:01 AM · #5

I found a manual for the Argus I previously mentioned, and a page in it describes the focusing method. (Edited my earlier response to be more accurate now that my memory has been refreshed.)

I do recall having one camera that had a "ghost" image to focus with instead of a split image like this one does. Don't remember what model it was, though.

Message edited by author 2010-03-04 10:14:07.

Bear_Music

Samsung Galaxy S24, S24+, S24 Ultra

Sony 24-70mm f/4 Vario-Tessar T* FE OSS

03/04/2010 12:42:46 PM · #6

The description of how they work is correct; two images are brought into alignment to focus the camera. They are called "rangefinders" for a reason: the original application of this technology was the development of tripod mounted devices used by artillery officers to find the range when they were targeting. In this context, "range" = "distance from where you're standing to what you're shooting at." :-)

Not all that long ago a hand-held, golfer's rangefinder was a popular gadget; make 2 flags into 1 and you had your range-to-target. That was superseded by a laser device, and THAT's been overtaken by GPS now...

R.

Message edited by author 2010-03-04 12:44:45.

Samsung Galaxy S24, S24+, S24 Ultra

03/04/2010 12:56:49 PM · #7

Originally posted by Bear_Music:

The description of how they work is correct; two images are brought into alignment to focus the camera. ...

Hmmm. I bet this was handy then for DOF, yes/no? If your subject was in the foreground and you aligned for focus, you'd see what's OOF.

Bear_Music

Sony 24-70mm f/4 Vario-Tessar T* FE OSS

03/04/2010 01:05:53 PM · #8

Originally posted by glad2badad:

Originally posted by Bear_Music:
The description of how they work is correct; two images are brought into alignment to focus the camera. ...

Hmmm. I bet this was handy then for DOF, yes/no? If your subject was in the foreground and you aligned for focus, you'd see what's OOF.

NO, because the focusing was not through the lens. So the visible DOF in the viewfinder had no relationship whatsoever to the DOF produced by the camera lens, which would vary based on focal length and aperture.

R.