First look preview of X100 at dpreview.com

Frankie said:
It is really not understanding how an encoder works that caused a lot of questions...you are not the only one in RFF.

Encoders are available in rotary or linear forms. Rotary encoder can only rotate 360-degrees...period.

[Liner encoders are essentially a very fine scale and EXPENSIVE, unlikely being used within a lens, else there will have to be a mechanical coupling between the ring and encoder "read-head"].

In AF mode, rotating the focusing ring around and around means nothing.

In any case, rotating the lens ring around and around simply means restarting at the 0-degree position whether you intend to or not. The 0-degree position can be marked or unmarked, hard-stopped or not. Whether the X100 focusing ring can rotate clockwise or counter-clockwise is immaterial...it is still limited to 360-degrees.

So, all you need to do is to selection clockwise or counter-clockwise mode; set desired focal distances and mark the focusing ring.

And, if the X100 only needs 165-degrees to focus from infinity to near limit, then the firmware can and will have to also place any arbitrary ring position to the nearest effective position [and that was how encoders are reset to zero positions in engineering applications].
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That's all very well and good, but it's not going to work like you think. If you place a mark on the focus ring, it could be focused at 1 meter right now, and then correspond to 5 meters in 20 minutes after rotations, mode changes, on/off, etc.

I don't know if you've ever used lenses that aren't mechanically coupled or not, but there are so many that can rotate forever, and plenty that have clutches. I have never seen a fly-by-wire lens on a camera or video-camera that has a specific degree rotation hard linked to a focus distance. Ever.

It is very likely for the focus ring to only pass on when it's being rotated, in which direction, and by how much. The lens is not going to pop to a certain focusing distance when it's switched to MF mode, it will stay exactly where it is till the lens is rotated. Focusing marks on the focusing ring will be useless.
 
videogamemaker said:
That's all very well and good, but it's not going to work like you think. If you place a mark on the focus ring, it could be focused at 1 meter right now, and then correspond to 5 meters in 20 minutes after rotations, mode changes, on/off, etc.

I don't know if you've ever used lenses that aren't mechanically coupled or not, but there are so many that can rotate forever, and plenty that have clutches. I have never seen a fly-by-wire lens on a camera or video-camera that has a specific degree rotation hard linked to a focus distance. Ever.

It is very likely for the focus ring to only pass on when it's being rotated, in which direction, and by how much. The lens is not going to pop to a certain focusing distance when it's switched to MF mode, it will stay exactly where it is till the lens is rotated. Focusing marks on the focusing ring will be useless.
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Except fixed infinity-focus lens [such as aerial camera lenses I spend my career in], all lens focal positional changes, whether via a railing system or helical rotation are related to focal and focus distance changes within its design range. A distance marking on the lens barrel is, in effect, a way of encoding focal distances; likewise with markings on camera monorails.

Indeed, and as I have already said, when switching to MF, the lens IF unit will focus the lens at wherever the ring [encoded] position is at...whether you intended it or not. That position could be infinity or closest focus position [depending on whichever end is is at the closest angular position to the arbitrary focusing ring encoded position, or might just happens to be within the effective range and at 14.271m].

[If I were the firmware designer, I would default reset the fixed lens in MF mode at the hyperfocal distance...]

Then you set your intended focal distance manually and leave the ring alone. If firmware allows, set a couple more zones. [That was why I posted long ago that the ability to also set far and near zones via the Fn+jog is desirable... having three preset zones is better than just one.]

The whole point about zone focusing is not to refocus the lens after it is set...allow DoF to cover the intended scene depth. So set the lens at the mid-point or your sweet spot in that DoF zone. The OVF is always in focus and won't distract framing acuity...essence of RF street photography.

As to the X100 IF specifics, no one knows except Fuji. However, I start posting about zone focusing via encoders only after seeing the picture of the Fuji lens unit. The marking of the lens ring is only one shorthand method.

I simply apply basic encoder engineering.
 
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Frankie said:
Indeed, and as I have already said, when switching to MF, the lens IF unit will focus the lens at wherever the ring [encoded] position is at...whether you intended it or not.
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We're both just posting our own opinions, but if it works like every other focus by wire lens on consumer cameras, this is just not how it works. You will switch to MF mode and the lens is going to sit there, no moving, no focus change whatsoever. It will wait till you rotate the focus ring to move, and it's not going to snap even then, it will start to slowly focus in the direction you are moving it. It provides rotational change data, not absolute position in rotation.

V V V what this man said V V V V
 
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Frankie said:
Indeed, and as I have already said, when switching to MF, the lens IF unit will focus the lens at wherever the ring [encoded] position is at...whether you intended it or not. That position could be infinity or closest focus position [depending on whichever end is is at the closest angular position to the arbitrary focusing ring encoded position, or might just happens to be within the effective range and at 14.271m].
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Your statement above assumes that the focusing ring features absolute position encoding, i.e. that the ring will contain a unique position code which establishes a unique relation between one lens focus position and one ring position.

While I agree that this would be nice, it would have two disadvantages:
  • Assembling the focus ring would become much more complex in production.
  • If the lens is operated via autofocus, the lens will be moved independently from the ring's position (There are compelling indications that this will indeed be the case). So, any subsequent operation on the focusing ring could possibly cause the optics to be moved in a potentially large jump to follow the ring's absolute position. This would result in a very user-unfriendly and intransparent operating behavior.
I am quite sure that the focusing ring will rather contain relative position encoding, i.e. it has position clicks, and lens focusing movement will be based (a) on the lense's inital position plus (b) on the number of position clicks that are delivered by the ring's relative encoding. This would also explain why the ring does not contain any position markings, as these would not make sense with relative encoding.

It remains to be seen whether the camera will feature focusing presets for hyperfocal and various zone settings. All of these will be preset electronically, so I cannot see any reason in marking the focussing ring.
 
Frankie said:
Indeed, and as I have already said, when switching to MF, the lens IF unit will focus the lens at wherever the ring [encoded] position is at...whether you intended it or not.
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Based on my experience with Nikkor A-M/A lenses, this is quite a leap of logic, and I don't share your confidence. Not only will the lens "start off" in manual focus mode at wherever the AF last left it—thus throwing off your ring's calibration—but on some lenses—...

...damn. I penned that an hour or two then forgot about it. Looks like vgm covered the same ground in a reply, too. Carry on.
 
Arjay said:
......It remains to be seen whether the camera will feature focusing presets for hyperfocal and various zone settings. All of these will be preset electronically, so I cannot see any reason in marking the focussing ring.
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Exactly.

I only offered ring marking as a substitute to the virtual "Focal Distance + DoF" scale that many do not believe exists...illustrations published by Fuji notwithstanding. I do not understand why using the "FD+DoF" scale in the LCD display to preset a zone is so "un-candid"...the camera would be at waist level as would be in presetting a lens the old fashioned way.

In ring marking, indexing to a known position is always key...howsoever obtained. I and anyone else will know better when Fuji had more to say...hopefully soon.
 
Isn't it amazing fun to speculate on a camera none of us has seen? The new camera specs are like a Rorschach test for your approach to the promise of new technology. I would submit that the teasers thrown into the water by Fuji are like blood in the water to a crowd like us.

Ben
 
Right now, the camera represents hope... hope that someone is going to do it right. I bet that once it is released, even more threads will be going crazy over it... both good and bad. The arguments have only just begun.
 
jsrockit said:
Right now, the camera represents hope... hope that someone is going to do it right. I bet that once it is released, even more threads will be going crazy over it... both good and bad. The arguments have only just begun.
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Long ago around Photokina 2010 week, I posted elsewhere in RFF to say the X100 represents "promised land", while the M9/ti represents "let them eat cake".

I was surprised that I didn't get busted.
 
To me the X100 is exciting for both practical and ideological reasons.

Practically I like to shoot with an external flash a lot and always hot annoyed that w/the M4/3 cameras I'd have to make a decision of the VF or the Flash.

The X100 brings back a VF and lets me use the flash, so right away even if the look wasn't there I'd prob get it as it does what I want a large sensor-relatively compact camera to do.

But the look is also important and goes in the direction I hope this mid level of cameras will go - where images quality is important but they form their own aesthetic path and aren't just stripped down DSLR's.

I'd like to see compacts remain snappy, dslr's become all full frame and feature rich and this mid level of APS-C sensor be about look and feel and experience as much as anything else. The X100 ticks that box for me.

For example, imagine an iconic 60's movie with Cary Grant and Audrey Hepburn and they're walking along the beach front in the French Riviera and he's taking her picture as they go. What camera would befit that moment? I can't imagine him going ok I'll just get my Ixus out or let me grab my Nikon D3X, it just doesn't fit to the image. He'd have a Contax T3 or a Leica M7/9, they fit the image.

So that's what I'd like this mid-range of cameras to become and why the X100 design is exciting. It's classic/retro but iconic in the same way RayBan Wayfarers are, they're old but modern.
 
andrew00 said:
I'd like to see compacts remain snappy, dslr's become all full frame and feature rich and this mid level of APS-C sensor be about look and feel and experience as much as anything else.
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Although my DSLRs are all going to be full frame crop bodies are here to stay. There is a huge advantage on crop bodies for sports, nature, astrophotographers and even paparazzi. A 400mm f/2.8 effectively becomes a 640mm f/2.8 on a crop sensor. And this is a huge advantage to the consumer.
 
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There's actually a lot of momentum in the rumor mill that canon will merge the 1d lines for a more solid product lineup that doesn't cannibalize itself.

I agree that aps-c is here to stay though, it's obvious looking at the latest gen of sony sensors that the sensor real estate loss over full frame sensors isn't particularly detrimental to IQ, and they can make crop bodies smaller, and the lenses smaller - like the x100. It's a good compromise.
 
While I would love a full frame Fuji X100. Or, Nikon compact mirrorless FF with pancake lenses, I have to agree with you. Loss of about one stop of DOF aside, there IQ difference between APS-C and FF at the sizes I print is not significant and perhaps most of us couldn't even tell the difference in a double-blind test. The emotional allure of FF is still very powerful for many, though.
 
The only reason I want full frame is it is what I'm used to using with legacy lenses. As long as companies make great new lenses to use with a crop sensor, I have no issue using a crop sensor.
 
jsrockit said:
The only reason I want full frame is it is what I'm used to using with legacy lenses. As long as companies make great new lenses to use with a crop sensor, I have no issue using a crop sensor.
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Exactly. I switched from a 40D to a 5D to get that gorgeous 35mmL to be wideangle. The only crop solution is the 20mm 1.8 sigma which is smeary as hell below f2.8. The 35 (either actually, L or f/2) wide open on a 5D spanks the sigma on a crop. If there was a good wide angle sub F2 lens I'd have never switched.

Same with the m4/3. The 20mm 1.7 looks very nice indeed, but I don't really like the sensors or bodies so much. If the Nex had something not quite so wide and not f/2.8, that would be interesting too.

For all the promise that these smaller sensors would yeild smaller lenses, i've yet to see it come to fruition other than the 20mm 1.7 from panasonic. A 3.5-4.6 zoom is quite small on a dslr too.

What's more important about the X100 is that it's a 35mm equivalent f/2 in light gathering abilities (if not dof). A full frame would be nice if it was actually small, but so far... well it hasn't happened at an affordable level yet. (for us proles at least)
 
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