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> F105W which is basically the same watch with a vastly improved backlight Can’t stress this enough. The F-91W is useless at night because the backlight bright
by TedDoesntTalk 4y ago
> F105W which is basically the same watch with a vastly improved backlight
Can’t stress this enough. The F-91W is useless at night because the backlight brightness is terrible. The F105W has an indiglo-style “EL” light that is very effective. The two watches are nearly identical from an aesthetic perspective. The functions are identical as are the buttons.
- 3pac 4y agoIndiglo has good looks and function. What I dislike is that it requires a high-voltage driver. As tiny and low-current as that may be, it is electrically and even slightly acoustically noisy, and not something that belongs in a low-voltage wristwatch.
- TedDoesntTalk 4y agoConsidering I might turn it on once per night for a second or less, I’m not concerned. Is the risk that it affects the timekeeping?
- myself248 4y agoWhy not? An incandescent backlight _physically gets hot_, I'd argue that has even less place in this application. It's just what they had at the time. But in either case, it's perfectly safe. There's no way to touch either the hot parts or the high-voltage parts. And even if there was, the battery doesn't have enough oomph to do anything more than tingle once the prickly part was trying to drive something as massive as a fingertip. I noticed the noise too, when I owned one, but I figure silencing it would've cost size, weight, and power. And the noise was never more than a curiosity, so I'll take it!
- Brian_K_White 4y agoThey aren't talking a out safety, they're talking about efficiency and accuracy. A boost converter is inefficient and you don't have power to waste like that in a watch. And electrical noise perturbs the timekeeping parts. However your comparison to incandescent and your point about the momentary nature are both valid I'd say. If they had magic, they'd have used it. So they took something fundamentally inefficient and added engineering to make the best of it. A bad thing, done as well as possible, You could say almost the same things about incandescent. It's not electrically noisy, but temperature sure does perturb the timekeeping, and incandescent definitely wastes power. Especially if you need the filament to last indefinitely instead of replacing it easily.
- galangalalgol 4y agoI've never had any problems with my f-91w at night. I can't use it as a reading light like the EL backlights, but it also doesn't ruin my night vision.
- frosted-flakes 4y agoHow does the brighter backlight affect battery life? Doesn't the original model have a 7-year battery life?
- TedDoesntTalk 4y agoI think EL uses less current than an incandescent, which is what the F-91W has. Anyway, the battery life always lasts longer than the band for me. Years. I replace it when the band tears, which is before the battery dies.
- somat 4y agoIs it incandescent!? I would have expected an led, or at least a process improvement where it was replaced by an led.
- TedDoesntTalk 4y agoIt’s still an incandescent, unfortunately. If they changed it to an LED, it might be bright enough to be useful.
- icybox 4y agoAllegedly, it's LED now: 'The small light bulb was replaced by a LED diode, but the intensity of the tired firefly remained' https://www.hodinky-365.com/blog/casio-f-91w-review https://www.hodinky-365.com/blog/casio-f-91w-review I wear F-91W every day and FWIW, the light is adequate to see time at night.