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and which Oly rangefinder do you rate as best - and why.

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It`s got to be the XA simply because the lens is superb.I wouldn`t be without mine.I have used but never owned an OM.
Dave

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If it wasn't for bad luck, I wouldn't have no luck at all - Albert King
my flickr

Edited by swanseadave (13/06/2008 13:37)

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For me the OM1n. Light, compact, with bright viewfinder and high quality prime lenses. Also durable body and mechanical shutter, so there is little to go wrong. I still own one which sees occasional use.

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but the OM2n for me shows Olympus at their best - OTF metering was pure genius

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I'm no Oly expert, but wasn't it off the shutter curtain, rather than OTF? A marketing gimmick, I thought, especially with that random pattern on the curtain to give a centre-weighted effect - pure marketing nonsense.

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Huw Evans.

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but the OM2n for me shows Olympus at their best - OTF metering was pure genius

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I'm no Oly expert

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Clearly.

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but wasn't it off the shutter curtain, rather than OTF? A marketing gimmick, I thought, especially with that random pattern on the curtain to give a centre-weighted effect - pure marketing nonsense.

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Yes and no. In aperture priority, for short exposures, 1/60 and above, it used the curtain - for longer exposures, it actually read the light off the film during exposure - up to a couple of minutes.

Oh, and the meter sensitivity ran down to something crazy like EV -5.5 to actually USE that two minute exposure.

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Nick

www.nbrphoto.com

Light and Shade II - the new blog

Edited by Benchista (13/06/2008 14:44)

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for longer exposures, it actually read the light off the film during exposure - up to a couple of minutes.

Oh, and the meter sensitivity ran down to something crazy like EV -5.5 to actually USE that two minute exposure.

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Okay, okay - you win! ;-)




[I stand by what I said regarding the randomized shutter curtain drivel though. :-)]

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Huw Evans.

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[I stand by what I said regarding the randomized shutter curtain drivel though. :-)]

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Fair enough - although I'm a self-confessed OM fanboy, I've always thought that bit was daft, too. Worst thing is that they used more than one pattern during the life of the camera... Still, I rate the OM2n as one of my favourite cameras of all (and I reckon the real reason I went for it ahead of the OM1n is that I actually prefer the Pentax MX to the OM1 by a touch).

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Nick

www.nbrphoto.com

Light and Shade II - the new blog

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[I stand by what I said regarding the randomized shutter curtain drivel though. :-)]

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But why was it drivel? Is it any more drivel than Canon's ineffective dust reduction system?

Seriously though, the whole idea of the pattern was that it provided the same light reflectance as film, so it didn't matter whether the light sensor read from the film or the shutter curtains.

It is much easier (and more reliable) to produce a black shutter curtain with a white pattern on it than a grey or brown shutter curtain, as it is more likey that light reflectance will change during its working life.

The pattern is required so that reflectance (as seen by the sensor) remains consistent throughout the shutter travel.

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Nigel CRIPN and Bar

Beware of the Dark Slide

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[I stand by what I said regarding the randomized shutter curtain drivel though. :-)]

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But why was it drivel? Is it any more drivel than Canon's ineffective dust reduction system?

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Seriously though, the whole idea of the pattern was that it provided the same light reflectance as film, so it didn't matter whether the light sensor read from the film or the shutter curtains.

It is much easier (and more reliable) to produce a black shutter curtain with a white pattern on it than a grey or brown shutter curtain, as it is more likey that light reflectance will change during its working life.

The pattern is required so that reflectance (as seen by the sensor) remains consistent throughout the shutter travel.

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Sounds like a good explanation to me.

I just picked up an Olympus S rangefinder with a fixed G.Zuiko 42mm f1.8 lens, for the princely sum of £6 from a local charity shop. I haven't used it yet, but it seems a mighty fine piece of kit. It has cds metering, a moveable brightline frame (for paralax) and long base rangefinder (19th down the page here). Recently bought an almost mint OM-1n which is simply beautiful. Needs new light seals though so not tried it out yet either. Which are the nicest reasonably priced OM lenses?

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Rob

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[I stand by what I said regarding the randomized shutter curtain drivel though. :-)]

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But why was it drivel? Is it any more drivel than Canon's ineffective dust reduction system?

Seriously though, the whole idea of the pattern was that it provided the same light reflectance as film, so it didn't matter whether the light sensor read from the film or the shutter curtains.

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It was the implication that the randomization had some benefit that was drivel, scientifically speaking. All that was necessary was that there was an appropriate average density to give the required degree of overall gain. A regular grid of evenly spaced white spots with the same average density would have given exactly the same degree of metering accuracy over the same range of scenes.

Introducing the concept of randomization, was, from a technical point of view, the light-metering equivalent of those ads for cosmetic products that are packed full of scientific-sounding language, which serves only to dupe the non-scientifically minded into thinking that there's something special there that will actually reverse the aging of skin, or whatever. It's a classic marketing/advertizing trick - present the consumer with technical stuff that will impress them even if it means nothing. And in the mid 1970s, telling Joe Punter that something was a computer-generated random pattern simulating the reflectance of film was enough to impress. "We calculated the dot size and spacing in 20 seconds with a slide-rule" wouldn't have sounded nearly as good, but that's all that was really needed. Back of an envelope would have been enough, when you get right down to it.

As for ineffective anti-dust systems, well, you don't expect me to defend the gasfire people, Shirley? :-)

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Huw Evans.

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[I stand by what I said regarding the randomized shutter curtain drivel though. :-)]

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But why was it drivel? Is it any more drivel than Canon's ineffective dust reduction system?

Seriously though, the whole idea of the pattern was that it provided the same light reflectance as film, so it didn't matter whether the light sensor read from the film or the shutter curtains.

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It was the implication that the randomization had some benefit that was drivel, scientifically speaking. All that was necessary was that there was an appropriate average density to give the required degree of overall gain. A regular grid of evenly spaced white spots with the same average density would have given exactly the same degree of metering accuracy over the same range of scenes.

Introducing the concept of randomization, was, from a technical point of view, the light-metering equivalent of those ads for cosmetic products that are packed full of scientific-sounding language, which serves only to dupe the non-scientifically minded into thinking that there's something special there that will actually reverse the aging of skin, or whatever. It's a classic marketing/advertizing trick - present the consumer with technical stuff that will impress them even if it means nothing. And in the mid 1970s, telling Joe Punter that something was a computer-generated random pattern simulating the reflectance of film was enough to impress. "We calculated the dot size and spacing in 20 seconds with a slide-rule" wouldn't have sounded nearly as good, but that's all that was really needed. Back of an envelope would have been enough, when you get right down to it.

As for ineffective anti-dust systems, well, you don't expect me to defend the gasfire people, Shirley? :-)

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That's a fair explanation Huw. However, I still wonder whether there may be another (less technical) explanation for the randomised pattern that didn't appeal to the marquetry people, but was necessary nonetheless. Your solution of using a series of dots sounds eminently sensible to me, but if the shutter is moving quickly, a uniform pattern might create a strobe effect under some conditions, which could (conceivably) confuse the metering system.

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Nigel CRIPN and Bar

Beware of the Dark Slide

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That's a fair explanation Huw. However, I still wonder whether there may be another (less technical) explanation for the randomised pattern that didn't appeal to the marquetry people, but was necessary nonetheless.

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That's a fair explanation Huw. However, I still wonder whether there may be another (less technical) explanation for the randomised pattern that didn't appeal to the marquetry people, but was necessary nonetheless.

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I don't think it was a random pattern, I think it was the same on every camera.

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Yes, I'm sure it was, or very similar (depending on how the shutter curtains were made and cut).

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Why shouldn't an apparently random pattern be used, it makes as much sense as anything else?

Surely modern "evaluative" meter patterns work more or less the same way?

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Yes. And at microscopic level, even white dots would have randomly arranged particles of TiO2 in them.

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Nigel CRIPN and Bar

Beware of the Dark Slide

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but if the shutter is moving quickly, a uniform pattern might create a strobe effect under some conditions, which could (conceivably) confuse the metering system.

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I think you're clutching at straws somewhat. But anyway, the metering cells of the OM2(n) received light from wide areas, rather than narrow spots, so there would be no difficulty at all in avoiding any significant strobe effect. For any given average reflectance the spacing of the white dots only needs to be kept inversely proportional to their linear dimension. Then, for any given metering cell pattern the range of fluctuation of the response for a reading off a moving curtain can be made as small you like by adjusting the dot size.

But really, all this is way, way over the top. The notion that a simple plain shutter curtain with the right reflectance couldn't have been used is just fanciful. Oly's pattern was a gimmick - nothing more and nothing less. I've granted Nick his point about OTF measurement during the long exposures - that's fair enough, but the randomized shutter curtain pattern was utter drivel. :-)

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Huw Evans.

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