Multiplying factor for framelines

[sharookh]

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Considering the multiplying factor of 1.3 with the M8, do the framelines in the viewfinder change as well to account for this factor - i.e. would a 35mm frame change to a 45.5mm?

 

Best

Sharookh

[scott kirkpatrick]

Considering the multiplying factor of 1.3 with the M8, do the framelines in the viewfinder change as well to account for this factor -

 

Yes, the frames lines are corrected for the 1.33x factor. Since Leica lenses work on film (full frame) as well as digital M's, the frame line referred to as "35mm" actually represents an effective 47 mm field of view. Same for the 24, 28, 50, 75 and 90 mm frame lines in the M8. All show the corrected (actual) field of view.

 

scott

[sharookh]

Scott -

 

Thanks for the clarification. I'm expecting my M8 this week and was a bit concerned about whether it would be a WYSIWYG.

 

Cheers

Sharookh

[marknorton]

Though of course, the ability to see immediately what you've shot will tell you that the framelines are a guide only; they tend to be more exact at close focus; further out, you'll get more than the frame suggests. As you get used to it, you can frame that little bit tighter and still get what you want in the picture.

[egibaud]

Last friday I met Artemio and we made some testing with several lenses.

 

The 35mm match the frame lines

The 50mm actually shoots a bit wider than the frame lines

The 90mm actually shoots the thickness of 2 or 3 lines wider than the frame lines

 

and we try a 135mm that has a magnifyer attached to it and brings the 90mm. It is actually easy to shot with it... but the actual pictures is about the thickness of 5 lines wider than the actual frame.

[scott kirkpatrick]

It's worth self-calibrating for the lenses you like, but I understand that the M8 philosophy is to set the frame lines to be accurate at 0.7 m. That gives a testable prediction.

 

Using the thin-lens formula, the distance from lens to image is increased by a factor of roughly (focal length / 70 cm) when you are focusing at 70 cm. That means with a 9 cm lens that to focus at 70 cm you are extending it by 9/70-ths or about 12%. When you instead focus on an object at infinity, so that the lens to image distance is the focal length, the angle that an object at the edge of the actual image makes is increased by 12%, which is a big effect. If the viewfinder frame is set for 0.7m on a 35mm lens, then an object at the edge of the frame at infinity is really 5% further out, which is still noticeable. In fact, I think I am getting more than the predicted 3% outside the frame on distant objects with a 24mm lens, so i will go back and check this by doing a careful comparison.

 

scott

[Gilles L.]

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My 50 summicron indeed shoots a little larger than the frame line...

[sharookh]

Is the self calibrating procedure tedious? Does the camera instruction manual come with instructions for this if required?

[scott kirkpatrick]

Is the self calibrating procedure tedious? Does the camera instruction manual come with instructions for this if required?

 

No, and no. I suppose it depends on your self, since that is what needs to get calibrated. I would use doors, buildings and table tops, rectangular objects with clear edges at known distances, like 1m, 2 m, 10 - 20 m. Carefully frame the known object to go from frame line to frame line sideways or top to bottom, shoot and look at the resulting picture carefully to see how much more you get. Doing it with a tripod takes longer but removes a source of error. Do it for each lens that you normally use.

 

scott

[robsteve]

Is the self calibrating procedure tedious? Does the camera instruction manual come with instructions for this if required?

 

I think Scott might have got you a bit confused. There is no calibration possible with the frame lines of the M8.

 

What he was trying to say is you need to get used to framing with the M8 and realize that at further distances, the picture will have more than the framelines indicated. This was true with the film M cameras as well, but we didn't have the instant feedback of the digital image.