Inaccurate framelines M4-P/M6/M7/MP +/-MA

[TomB_tx]

Advertisement (gone after registration)

Reminds me of the debates over film SLR viewfinders in the 1960s - some claimed to cover 100% of the frame while others were 90-95% of the frame. Of course most shot color slides then, and the mounts covered a few % of the edges, as did most negative carriers for enlargers, and people would crop anyway to fill an 8x10 print... as is true for me with shots from my Leicas - if you put important details close to the frame edges be prepared for surprises.

Cropping is the only post-processing I do consistently on both film and digital. 

I've never understood the concerns, except people would always like to argue such details over automotive specs and other things. So I drove a VW Beetle, enjoyed my various M cameras, and didn't worry about it.

Edited December 26, 2024 by TomB_tx

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[UliWer]

vor 3 Stunden schrieb DimLs:

With a simple google search one can see that...

You didn't state where you searched with google to find this information.

My search went to the Leica website and there to the downloads with instructions for the M-A, MP and new M6. On p. 31 the English version of the instructions for the new M6 says:

"The size of the bright-line frame corresponds to an image size of approx. 23 x35 mm (slide format) at the shortest setting distance for each focal length."

You'll find the same in the instructions for the M-A and MP. But then the manual for the new M6 (and only for the new M6 not for the MP or M-A) says: 

"At distances under 2 m, the film captures slightly less than indicated by the inner edges of the bright-line frame, and slightly more at longer ranges (see adjacent diagram)." 

So there is an obvious contradiction in two sentences of the new M6 manual: are the frames exact at "the shortest setting distance for each focal length" or at 2m (which is never the minimal focal distance for any M-lens).

I may be wrong though I am rather sure, that the second quoted sentence about 2m in the M6 manual is wrong as well as the "adjacent diagram". Leica has the very bad habit to copy and paste from one document to another paying no attention whether the copied statement fits the context it is pasted to. The sentence about two meters with the diagram and further explanation comes from the manual for digital M bodies: the new ones since the M10 have framelights calibrated to 2m. Traditionally - for  film M bodies and the first version for the M8- it was minimal focussing distance for the different lenses, i.e. 70cm up to 75mm and 1m for 90mm and 1,5m for 135mm. 

I may be wrong though and the bad habit of copy and paste may have led to a wrong statement about the "correspondence" of framelines and imagesize at the shortest setting distance in the new M6 manual. This would either mean that they used two different rangefinder constructions for the new M6 and the older film M-bodies - which would be economically absurd. Or they changed the framelines for the MP and M-A during running production and didn't change their older statements in the manuals. 

Perhaps someone who has a new M6 and an MP or M-A as well can check: is there a difference? 

P.S.: Older thread about the topic: 

 

Edited December 26, 2024 by UliWer

[adan]

4 hours ago, DimLs said:

If this is true it means that Leica m4-2 and past models with 0,72 viewfinder had frame lines calibrated to be accurate for a focusing distance more than the 2m, something I have never read it in any online material and posts I have searched for.

Just the opposite.

Film M framelines up until digital arrived were "sized" (approximately) for the cropping at their minimum focus setting (0.7m for 75mm and wider lenses, 1m for 90s, 1.5m for 135s.).

Reason being that focusing at closer distances, a lens is moved out away from the film, projecting a bigger image onto the same-sized piece of film. Effectively a slightly longer focal length, with less in the picture.

Example: a 90mm lens focused to 1m has moved the glass, say, 1.5cm further away from the film than when focused at infinty or longer distances, so it is framing as though it is a ~105mm lens. This is sometimes referred to as "lens breathing," although the term is often misused.

So - on the assumption that missing out on part of the subject with no way to ever get it back was a bad idea, whereas getting too much in the final negative/slide could be salvaged by cropping - RF makers set the framelines for the "worst case" - accurate framing at minimum focus distance.

At longer subject distances one "gets too much" on the final negative - but that can be cropped down to what one saw in the framelines, if needed.

Additionally, in the film world, devices such as negative carriers or slide mounts tended to crop into the negative a little bit themselves. So a safety margin (you get more than you expected, and crop to suit) was always useful.

Additionally - again - the M frameline mechanism is made up of "stencils." Thin masking material with slits cut in it, for all the focal lengths, to pass plain white light.

But there has to be sufficient spacing between the close-together slits for, say, 50 and 75 and 90mm framing, or the masks can crack or tear. So Leica also "cheated" a bit in the spacing, always on the side of "you get more than you need - but at least what you need - in the final film."

When the 28 and 75 lines were squeezed in, in the M4-P (1983), all the slits had to be rearranged to allow 6 sets (28/35/50/75/90/135) to be cut in the masks (instead of just 4 or 3) without running into each other. So there were adjustments made to the 35, 50 and 90 frame positions/sizes to allow that "safety spacing." Those 3 frameline sets got even smaller (and even less accurate at long "landscape" distances).

Edited December 26, 2024 by adan

[comte de Mazan]

Hello,
I did an experiment to visualize the reality of the fields framed at 0.7m and 2m with a 35mm mounted on my MP.
At 0.7m, the negative corresponds exactly to the inner limit of the bright line frame.
At 2m, the negative corresponds to the outer limit of the bright line frame.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[jaapv]

 

 

 

 

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

 

 

[UliWer]

vor 4 Stunden schrieb comte de Mazan:

mounted on my MP.

if your MP was made before the introduction of the new M6 your test shows what you should expect from the manual or the explanation in Osterloh‘s book. If your camera was made after Oct. 2022 it shows that the MP rangefinder hasn’t been changed.

[comte de Mazan]

Advertisement (gone after registration)

2 hours ago, UliWer said:

if your MP was made before the introduction of the new M6 your test shows what you should expect from the manual or the explanation in Osterloh‘s book. If your camera was made after Oct. 2022 it shows that the MP rangefinder hasn’t been changed.

Yes, exactly. My Mp is from 2004.