Mike Johnston of TOP explains why Sony shouldn’t call its pellicle mirror “translucent”:
[...] “translucent” is just entirely—egregiously, blatantly—the wrong word. Translucent materials pass some of the light that falls on them and diffuse the rest. Muslin curtains, tracing paper, or frosted glass windowpanes in a bathroom are all translucent. An indistinct, fuzzy, or veiled image that’s hard to see is actually part of the definition of “translucent.” A pellicle mirror is a beam-splitter. That is, it passes some of the light transparently and reflects the remaining amount. There’s no translucency involved anywhere. Wrong word—and a bad connotation. Marketing fail? Heck, English language fail.
Wikipedia also notes that a “camera with a translucent mirror would produce an indistinct blob of light at the image plane.” A better word for people who might not know what “pellicle” means might be “semi-transparent”.
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