Leica M5 meter sensitivity

[vincenzo_maielli]

Dear friends, help me.

I have recently bought an excellent Leica M5. Now, the meter

sensitivity of the M5 cell is indicated in asb (apostilb) from 0,4

to 200.000 values (as wrote in the instructions manual). What are

the corresponding EV values? Thanks for your kindness.

P.S.: sorry for my bad english.

 

Best regards

 

Vincenzo Maielli Bari Italy

[kajabbi]

Vincenzo,

My M5's accurately read to a low of 4 EV at 400 iso. I did have my meter upgraded to use the 1.5 batteries but that probably would not have any effect on the sensitivity. If you can safely expose pictures ,handheld in dim light,you will be fine. I used them with the Noctilux, with no problem.

A syuggestion. If the M5 you acquired has not had a CLA, have it done. If you are here in the US. contact Sherry at Golden Touch as she is the reining expert on M5s. Once you get used to handling the M5 and it's spot meter, you will wonder why you waited so long to use one.

[tim_franklin]

Hi Vincenzo,

The table at the bottom of this article by Erwin states the M5 sensitivity to be EV 0 to 20

(in comparison, the current MP is EV -2 to 20.

 

http://www.imx.nl/photosite/leica/mseries/MP.html

[alan_wilder1]

I believe Erwin's chart may be incorrect but it also depends on which lens is attached. Gunther Osterlow's book is more accurate and as I vaguely recall, with the M5 @ EV100 measuring with an f/1.4 aperture, it's -1 EV. The trick is that the M5 only meters accurately down to f/1.4 and the MP can meter accurately as fast as an f/1 lens so this may affect the stated numbers.

[Rob F.]

". . . the M5 only meters accurately down to f/1.4 and the MP can meter accurately as fast as an f/1 lens . . . "

 

This requires a bit of interpretation. Both of these cameras read only a selected semi-spot area, not the whole frame. The Noctilux vignettes when used wide open, so that the illumination does not increase much when opening from f/1.2 to f/1. Thus the lens does not really pass twice as much light at f/1 compared to f/1.4. In most cases, the diode display registers no change at all when stopping down from f/1 to f/1.2. It usually does show a 1/2 stop change when stopping down from f/1 or f/1.2 to f/1.4. This is true of the MP, M6, and M7, which all use the same basic measuring system. Some knowledge of the meter's idiosyncracies with the f/1 lens is therefore needed to expose correctly at the widest aperture. Or should I say, some knowledge of the f/1 lens's behavior with the meter is needed to interpret the exposure difference between f/1 and f/1.2.

 

I'm sitting here in my semi-dark basement "cave" checking and rechecking my statement with the Noctilux and MP, pointing it here and there, sometimes including a light bulb in the center, sometimes in the corner, sometimes a blank white wall or a gray wall, etc. No matter what I do, I can't get it to show a change between f/1 and f/1.2. This has been discussed in print somewhere, outside of the forum. I find it to be true.

 

But the M5 should still show an increase in light at f/1.2, compared to f/1.4, just as the MP can. Both cameras measure through the lens, so any increase will register a change outside of the special case of the Noctilux at f/1.

[mark_unlisted]

No numbers to quote, just an observation and a comment from words in Boward's book. He believed the M5 was twice as sensitive as the M6 because, in his words, it made a direct rather than reflected measurement. The problem with the M5 is that it is impossible to see the match needle system in low light, at least at my age. I formerly loved my M5 but have gained a new appreciation for the M6. I have a black M5, Mint- with M6 frame lines and a recent CLA by Sherry (Jan 05) then a trip back to Sherry to get a broken frame counter fixed (Dec 05). It is for sale if anyone is really interested. Fantastic camera, even fits my hands better than the M6 but I just cannot see the needles anymore.

[alan_wilder1]

The information on the metering the M5 at no faster than f/1.4 came from Gunther Osterloh's book. He devoted quite a lot of detail to metering with this camera so I assume it's fact based condisering the design of the meter cell with it's "watch spring" baffle to block out light entering at too great an angle.