First of all, a happy July Fourth to our many American and Danish readers. It’s a good day to talk about taxation and representation, in this case, representation of our camera EXIF data. And, since we don’t have a holiday today in the UK, I am able to sit behind my computer and pound our yet another post for Macfilos.
One of the problems with using manual lenses, and I’m thinking mainly of M-mount lenses, with mirrorless cameras is the lack of aperture values attached to an image. It can make future reference something of a hit-or-miss affair and, as a writer, it is very inconvenient not to be able to quote aperture values for published images.
Sadly, this problem has been extant even with the Leica rangefinder in recent years. M-mount lenses are as dumb as they come, so there is no electronic jiggery-pokery available to populate the EXIF data.
Fortunately, Leica has produced a solution, a way of estimating aperture settings with reasonable accuracy. This isn’t new, of course. It used to happen with the M9 and the M240 but the facility disappeared when the M10 came along. I have example images from the M9 in 2012 which clearly show an aperture value. I also remember Leica announcing they had withdrawn the facility on the introduction of the M10 because it was not of any great use. I disagreed at the time and I’m glad they have now had second thoughts.
So how does it work?
Leica tells us:
“The camera compares the brightness measured through the lens with the measured ambient brightness to estimate the aperture used. This value is then written to the EXIF data. In some cases, the interpretation of the subject or scene may lead to incorrect estimation of the aperture value, for instance when shooting subjects or scenes with high contrast and black or white objects.”
This is intriguing and, of course, the potential problems in unusual circumstances are easily understood. Overall, though, the system gives a much better estimate of aperture than we can achieve by sight — perhaps checking the amount of bokeh in relation to the lens focal length. It’s hit or miss and I wouldn’t have the confidence to pontificate on the subject.
The new facility included with the latest M10 firmware is thus of great practical value to all photographers and I am really pleased that it has returned. In real terms, the calculated value is good enough.
Interestingly, the semi-intelligent manual lenses made for the Sony E-mount — such as the Voigtländer 40mm Nokton and 65mm Apo-Lanthar transmit accurate aperture values because of the electronic connection. And as I touched on yesterday in the motorcycle article, they are also able to initiate focus aids by detecting movement in the focus ring. The M10 (and all digital Ms) can also do this thanks to the mechanical focus linkage for the rangefinder.
I am grateful to William Fagan for pointing out that the M240 also reported estimated aperture and that it was only when the M10 was introduced that the facility was deleted. I’ve amended the above text to reflect this fact and I’m sorry for any confusion.
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The key value I have enjoyed in aperture values is helping me learn from failed images if depth of field is incorrect. I also use zooms by picking a focal length for the image and thinking about the aperture for the image rather than just looking through the viewfinder and zooming instead of using feet. The real value in a zoom is not having to change lenses when you are in rapidly changing subject types or bad weather but stronger images result if you treat them as variable primes and think about depth of field.
Hi Mike,
On another subject, I notice the exposure for the White House is about a stop over what I would guess using the
sunny 16 rule. I have noticed this with my digital cameras too.
Do you think the manufacturers fudge the ISO values a bit? Heaven forbid.
Philip
Ha! That image was taken six years ago so I’m not at all sure what was going on. You could be right about over-exposure which can be a problem with many cameras these days (depending on exposure setting — I tend to use centre-weighted and that can cause anomalies). The dynamic range of modern cameras, especially full-frame and MF, is so good that I am using -1/3 to -1.0 EV more often than not. As with the Monochrome, it’s easier to deal with darker areas than pull back blown highlights,
I think that you Brits can now proudly claim July 4 as your wn holiday. Just think, had we Yanks not departed, Donald Trump would be one of yours.
Happy Ttump’s not your problem day.
And if you had remained, perhaps as Greater Canada, you wouldn’t have had Donald, you’d have had an inoffensive little old lady on the throne, someone who wouldn’t offend anyone. So the head of state and the executive would be separated. Some think this is a good idea…..
We have our own Independence day… OK, so we aren’ t independent but that is a small detail, our day is June 23rd.
Brexit and Trump ARE the solution…
So perhaps we can share that on July the 4th.
Happy, "Trump is the solution day".
As William pointed out, the ability of showing estimated aperture values vanished with the M10. Like you I’m happy to have this back, because I missed it sorely.
Even if there is sometimes a slight deviation, most of the time it’s stunningly accurate and a big help. I for one need the exposure parameters to analyze images and of course (you mentioned it already) for publishing.
Claus
My M240 images show aperture values in Lightroom and always have done so. My M10 images did not show aperture values in Lightroom, but now they do so since the change in firmware. It is nice to have them, but, in truth, I have not missed them that much. The information is very much ‘after the event’ and given the mechanical nature of Leica Ms, the figures are always a ‘guesstimate’. None of my film Leicas have this feature, of course.
William
William, thanks. My memory must be playing tricks. Perhaps you are right and that the system worked for the M240 but was withdrawn on the launch of the M10 — which is probably what I was thinking about when I mentioned Leica’s announcement. I’d better check that and if necessary I’ll do a rider to the article.