M2 Illumination window

[blue4130]

Mine doesn't have a fresnel cover. Where they made this way or was this changed some time during the history of my camera?

Vance

 

[Artorius]

Fresnel

Fresnel

I think the M3, not the M2 had the Fresnel(stepped) window

 

[Shac]

My M2 has a stepped panel but it is behind a smooth glass panel 9S/N 941XXX), unl;ike eithejr the M6 or M4 both of which have no panelk infront of the stepping

 

[Bill Blackwell]

I think the M3, not the M2 had the Fresnel (stepped) window

Actually, that is incorrect. No M3 was produced with the "stepped" center light window - its center light window was always produced with just ground glass. Early M2 cameras had a unique "reversed" stepped window (the outer class was flat). From about mid-1959, and every Leica M camera model (after the M3) produced since, has had the now common stepped center window.

 

[Artorius]

I stand corrected

I stand corrected

Actually, that is incorrect. No M3 was produced with the "stepped" center light window - its center light window was always produced with just ground glass. Early M2 cameras had a unique "reversed" stepped window (the outer class was flat). From about mid-1959, and every Leica M camera model (after the M3) produced since, has had the now common stepped center window.

Must come from too, many M's and not looking to check.

 

[payasam]

The M3 had ground glass and the M2 had stepped. Unless I am mistaken, early M2s had many more "steps" than later ones.

Vance, could you please post a photo of your camera so that we see what it does have?

 

[blue4130]

http://www.photogeek.ca/uploaded_images/leica2-794489.jpg

http://www.photogeek.ca/uploaded_images/leica1-794447.jpg

Here is is on my blog (shameless plug for Where's My Leica?)
www.photogeek.ca

As you can see, mine has no stepped glass window, either internal or external. It is just a flat ground glass.

Vance

 

[Roger Hicks]

Both my M2s have stepped windows (975 xxx, 1 020 xxx), as does the black M2 on p. 177 of Paul-Henry van Hasbroeck's 150 Classic Cameras (black body, serial no. 1 130 287). In the engravings (I assume, photographically derived) in my 1967 catalogue, the M4 and M2 do, but the M3 doesn't.

Cheers,

R.

 

[oscroft]

My M2 (1 099 xxx) also has a stepped illumination window

 

[Bill Blackwell]

http://www.photogeek.ca/uploaded_images/leica2-794489.jpg

http://www.photogeek.ca/uploaded_images/leica1-794447.jpg

Here is is on my blog (shameless plug for Where's My Leica?)
www.photogeek.ca

As you can see, mine has no stepped glass window, either internal or external. It is just a flat ground glass.

Vance

Since it wasn't produced that way, the explanation is simple - a repair technician has replaced the center window with a M3 type ground glass.

 

[Rob-F]

The M3 didn't need a fresnel window because the frameline mask was in line with its illuminator window. In the M2 and all subsequent Leicas, with the redesign neccesitated by the reduction to .72 magnification, it was no longer possible to so locate the mask. It had to be relocated and angled, which in turn made it necessary to use a fresnel window to direct the light over toward a mirror, which in turn bounces the light to the relocated mask. All M's after the M3 share this fundamental design layout, and all must use the fresnel window.

You can see a schematic drawing of the finder layout either in Jonathan Eastland's Compendium, or in Osterloh; though the drawing in Eastland's book is easier to make out.

 

[furcafe]

Does this mean that Vance's M2 will have dimmer than normal framelines?

The M3 didn't need a fresnel window because the frameline mask was in line with its illuminator window. In the M2 and all subsequent Leicas, with the redesign neccesitated by the reduction to .72 magnification, it was no longer possible to so locate the mask. It had to be relocated and angled, which in turn made it necessary to use a fresnel window to direct the light over toward a mirror, which in turn bounces the light to the relocated mask. All M's after the M3 share this fundamental design layout, and all must use the fresnel window.

You can see a schematic drawing of the finder layout either in Jonathan Eastland's Compendium, or in Osterloh; though the drawing in Eastland's book is easier to make out.

 

[JNewell]

Pictures of early production M2 bodies in Lager show the stepped window. On a 900k body, it's an after-factory alteration.

 

[Paul C. Perkins MD]

Mine has the fresnel window. . .

 

[jfujita]

In addition to the M3 the original MP's had ground glass and so does my MP3... with a .72 viewfinder. Oddly enough my MP3 finder is brighter than my M7.