用底片拍照實際上能換來甚麼呢？先不算數量多得驚人的底片，如果要具體地說，別見笑，可能只是換來一堆無法忘卻的數字，例如光圈 f5.6，快門 1/125秒，簡直是直接刻進腦裡，把它解剖開來應該可以看到一個測光錶。
What have I gained from taking pictures with film? Aside from the astonishing number of film accumulated over the years, I would say I have an enormous amount of numeric figures permanently imprinted on my mind — aperture f5.6, shutter 1/125 second… If you were to cut open my brain, you’d probably find a light meter inside.
The most frustrating thing about film photography is incorrect exposure, and worst of all, when the entire roll of film is either overexposed or underexposed. Imagine how a supposedly beautiful and colorful sunset can turn into an overexposed image that looks more like a bright scorching midday sun; it’s just depressing. Even though it brings a lot of joy to anticipate how a roll of film would turn out, I still can’t get over the frustration of incorrect exposure. I once recalled seeing some light meters in a second-hand camera store, and it was then I began to wonder, “maybe I do need one.” Eventually, I went to get my very first light meter, and it turned out that the meter I selected is an antique that has an even older history than my camera…
My rough estimation is that this Mighty Star light meter was launched in 1959. It was produced in Japan by a little-known company called Walz during the recovery period after World War II. I didn’t know much about lighting when I first purchased it, but I was sure that having a light meter would easily solve all my lighting problems. Of course, I was wrong. I discovered that “learning from mistakes” is the only way to get the correct light reading. While the built-in light meter of my film camera is way too light-sensitive, this Mighty Star meter is the exact opposite; in darker places such as indoor environments, the pointer of the Mighty Star meter often points to “zero” which means no light detected.
I wonder whether this is what people consider “the wisdom of old equipment.” When auto-focus and auto exposure metering came into play as a major advancement in photography equipment, they completely transformed photography and changed how we photograph. Of course, I am one of those who benefited from being able to take pictures without doing much thinking or calculating. But on the other hand, the inaccurate light metering also forced me to begin using my own eyes as a light meter; I looked around and I observed. Eventually, I started to build up my own internal database about lighting and exposure. It is for that same reason I insist on using the Mighty Star light meter; if it fails to read, it usually means the environment is too dark. Such information is enough of an alert to remind me to make exposure adjustments accordingly.
After the mid-sixties, the much-criticized light meters from Mighty Star were gradually replaced because of their poor sensitivity to weak lighting, as well as the power-generating component in the meters, selenium, having a limited life span. Interestingly, this shortcoming of selenium is also the reason why I fell in love with my light meter: Selenium is a substance that generates electricity when exposed to light. It is very similar to photosynthesis. It does not require batteries. It also works like a compass as they are both solely run on physics. Selenium is such a magical substance, and its use is reassuring because it will not drag you into the disrupting dilemma of running out of batteries.
Light is like air, right? We can hardly prove their existence, or we can say, they are close to non-existent. If you point a light meter somewhere in the air and the pointer moves, it is light.