Electronic Coincidence-type Rangefinder

charge5photo

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This is a concept for an electronic, coincidence-type rangefinder. The concept is about having the ability to move the focus point around viewfinder or within the boundary of the framelines.

6044042295_43102b7113.jpg
 
Is that image the concept?

It looks cool. Needs more detail though imo. Like, would the amount of time spent repositioning the focus point be less than focusing and recomposing?
 
Is that image the concept?

It looks cool. Needs more detail though imo. Like, would the amount of time spent repositioning the focus point be less than focusing and recomposing?

Quite. And given that it would probably rely on similar technlogies to autofocus or focus confirmation, how is it more reliable or convenient? It looks like exactly the sort of thing a Japanese manufacturer might market as a gimmick, because they could, but I'm not sure how much use it would be to a photographer. And, of course, it's an EVF: they need to improve for at least a year or two before they are anywhere near an optical finder.

Cheers,

R.
 
Is that image the concept?

It looks cool. Needs more detail though imo. Like, would the amount of time spent repositioning the focus point be less than focusing and recomposing?

Focussing and recomposing can result in slightly out of focus images due to the focal plane moving as you do.

Could be useful if you know where you want your subject to be in the frame.
 
Nice idea, but EVFs will probably never be as accurate as optical viewfinders.

I'd rather have the new NEX-7 with its 3 mill. dot EVF and focus peaking then, thanks :)
 
Focussing and recomposing can result in slightly out of focus images due to the focal plane moving as you do.

Yes, that can theoretically happen if you're shooting at full aperture and close distances (how often does it actually happen, though?), but I'd be much more worried about losing the moment while I was faffing around with positioning the focusing spot. I mean, why not use a 5x7 inch and ground glass if you're not worried about speed? Or an SLR? Or stop down?

Cheers,

R.
 
Yes, that can theoretically happen if you're shooting at full aperture and close distances (how often does it actually happen, though?), but I'd be much more worried about losing the moment while I was faffing around with positioning the focusing spot. I mean, why not use a 5x7 inch and ground glass if you're not worried about speed? Or an SLR? Or stop down?

Cheers,

R.

If you had a particular photo in mind and you know where your subject will be then I would use it. Most of the time I wouldn't.

Is there a reason that the whole viewfinder can't be taken up with rangefinder patch? The double image might be a headache...
 
If you had a particular photo in mind and you know where your subject will be then I would use it. Most of the time I wouldn't.

Is there a reason that the whole viewfinder can't be taken up with rangefinder patch? The double image might be a headache...

Para 1: I think I'd just use a different camera, i.e. not an RF.

Para 2: Interesting thought, but (as you say) it might be a bit headache-inducing. There have been optical range/viewfinders where the whole image has been split, top/bottom, but obviously that precludes coincidence. But why not use an SLR if you want full-screen focusing? Surely most of the appeal of an RF is the bright, clear, uncluttered finder, with as little technology as possible between you and the subject.

I'm increasingly disinclined to say that anything can't be done, and although there are plenty of things that no sane person would do, they get done anyway, so I'm ever less willing to say that something won't be done. But this 'concept' seems fairly high on the list of things that are unlikely to be done.

Cheers,

R.
 
Is there a reason that the whole viewfinder can't be taken up with rangefinder patch? The double image might be a headache...
I guess a fairly nice solution would be a variable-size rangefinder patch (implementing an aperture for the image path of the rangefinder image). This would allow for "traditional size" and much bigger image depending on whether you want no headache or prefer some. ;) Actually, I think the use cases would be "capturing the moment" vs. "working with a static subject".

The real issue I believe would be the size and cost of the assembly. I'm afraid it would not allow for smaller cameras than Leica M or Bessa. Think at least M5 size for 135 or FF digital.
 
I would be satisfied with a "zoomed-Circle" for an EVF to magnify 10x for a chosen spot, even just the center. I find switching back and forth between magnified view and 1x view on the Olympus EP2 to be very difficult. Having a center spot, or movable spot to provide a 10x fine-focus and the rest of the finder to remain 1x view for composition would be much easier. The electronics are there, all they need to do is write some software. It would not be very hard to do. And given that this simple solution has not been written into the firmware, I doubt that the electro-optic system proposed here would be implemented.
 
The "zoomed-Circle" is what I have on my old Panasonic and it works well. I imagine it would be even better now and into the future with the improved EVFs coming out. I think Brian is right that an electro-optic system would be needlessly complicated and expensive to implement vs taking off the shelf technology. The mechanical coupled RF and the need to have it might be holding back the idea of what maybe the future ala Fuji X100. For those who need a mechanically coupled RF there is Leica and for those who want a small RF form camera an interchangeable lens camera similar to the Fuji X100 should do nicely.

Bob
 
If the X100 blind that pops up to cover the OVF when you engage the EVF, would have a square hole in it this would be achieved already.

With a hole in the blind, the OVF image would show through the EVF image and the focus ring of the lens when set to manual could be used to focus both coinciding images. I've been asking Fuji to consider this before the launch of the X100 but never had a reply. Guess my suggestion got swamped in the feedback on the new camera.

When in the future the X100 becomes old and cheap, I plan to Dremel myself a digital rangefinder from one.

We are real close to having an digital rangefinder unit on cameras. The titanium M9 had electronically projected framelines and I predict the M10 to have a digital RF unit.
 
Nice idea, but EVFs will probably never be as accurate as optical viewfinders.

...

I would think exactly the opposite.

The lag of an EVF does not produce the same level of spontaneity as an OVF.

However the focus accuracy of an EVF is not fundamentally compromised in any way. With my D700 I use Live View with a high degree of zoom (could be at least 50 X,I'm not sure) to nail hyper-critical focus independent of any small AF calibration errors (front or back focus). The limit to focus sensitivity with this form of EVF is determined by the mechanical limitations of the lens focus collar.
 
I would be satisfied with a "zoomed-Circle" for an EVF to magnify 10x for a chosen spot, even just the center. I find switching back and forth between magnified view and 1x view on the Olympus EP2 to be very difficult. Having a center spot, or movable spot to provide a 10x fine-focus and the rest of the finder to remain 1x view for composition would be much easier. The electronics are there, all they need to do is write some software. It would not be very hard to do. And given that this simple solution has not been written into the firmware, I doubt that the electro-optic system proposed here would be implemented.

Agree with Brian here.
A magnified region of the EVF is less jarring view-switching than the current implementations.

I would also get behind the idea of a simulated rangefinder. Kind of the one suggested here, sans the ability to move it around.

I've always wondered the usefulness of multiple focusing points for the kind of photography that I do (read: I don't do sport-action shots). I end up always moving the focus point right back to the center on my cameras that has multiple of them.

As Roger pointed out above, focusing and recomposing is second nature after some practice, even when the subject is "live" (not posed or inanimate).
 
Electronic Coincedence-type Rangefinder

Electronic Coincedence-type Rangefinder

One of things I forgot to mention was this is a optical hybrid finder similar to the X100. The difference is instead of the rangefinder using a mirror to reflect the focus point into the viewfinder, a small digital camera (similar to an iPhone) would display it in the hybrid VF. To be clear this a OVF with a HUD like display.

A hybrid VF and electronic rangefinder would open possibilities to enhance rangefinders. Framelines can adjust instantly with a zoom lens. You could adjust the size, shape and position of the focus point (as illustrated above).

What other features would be possible with a hybrid finder?
 
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