External (rangefinder) finder on an SLR?

D

Danny D

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I am thinking about getting a briteline finder and sticking it on my FM2, purely for zone focusing a 21mm lens. Is there any reason this wouldn't work?
How come I've literally never seen anyone use one of these on an SLR before?
 
That used to be the norm, back in the day. Extreme wide angle lenses (and a 21mm was considered extreme back then) didn't clear the SLR mirror; they were used with the mirror locked up, and an accessory finder that was sold as a set with the lens.
I assume it's not done now because contemporary lenses don't need the mirror lock-up; an accessory finder is redundant. Of course, there's no reason not to use one, if you want!
 
I use one on my Bessa L with a 21mm CV and it does an alright job. Goes really haywire for anything close. I'm trying to understand the rational in using one.
 
I guess you only want an external optical finder and not really a rangefinder, but since you wrote it, i wanted to show my avatar i have used since i registered here on RFF.
It have newer actually used it on the FM2.
 
Darthfeeble said:
I'm trying to understand the rational in using one.
Click to expand...


When you look through the viewfinder of an SLR, while zone focusing, pretty much everything is out of focus. There is the depth of field preview lever of course, but this kind of defeats the object of zone focusing: putting the camera to your eye and very quickly snapping a shot off.

I have a voigtlander briteline finder on the way now. Also, I'm curious about why you'd have an actual rangefinder on an SLR? To go with an Nikon E grid screen I suppose?
 
Useless exercise, except your 21 is f1.5.

I used 19, 21 f3.8 lenses, DOF is so huge @f3.8, it makes all visible at regular focusing distances which are in use for scale focusing.

Don't forget, many lenses will accept cable tie and focus tab. With this you could focus without looking at lens or in VF.
 
I had a setup with a leica R 21mm f3.5 on a leicaflex standard (mirror lock up version) with the external 21mm finder. I thought it was a little unwieldy, and switched to a Leica IF with a screwmount 21mm and external finder

It can be done, but I didn't like it personally. Even though it looked pretty badass.
 
With the finder perched on top of the prism, I expect there would be a fair bit of parallax. But, you always have the camera's viewfinder available if you need precision.

Another approach, which may not be applicable for your camera, might be a clear focusing screen of the type meant for extreme magnification. The image on these always appears "in focus", and they are very bright. I think Nikon made such a screen for the F models, not sure about any others, though finding one is probably much more difficult than popping a viewfinder on top.
 
Danny D said:
When you look through the viewfinder of an SLR, while zone focusing, pretty much everything is out of focus. There is the depth of field preview lever of course, but this kind of defeats the object of zone focusing: putting the camera to your eye and very quickly snapping a shot off.

I have a voigtlander briteline finder on the way now. Also, I'm curious about why you'd have an actual rangefinder on an SLR? To go with an Nikon E grid screen I suppose?
Click to expand...
Because the SLR is an Alpa, perhaps? They gave the choice of rangefinder or reflex focusing in several models by making both systems part of their camera. You can probably blame Jacques Bolsky for that being the designer of what became the original Alpa Reflex. But only 50mm lenses were rangefinder coupled. Odd, but not that much odder than fitting a Rolleimeter accessory rangefinder to a Rolleiflex TLR.
 
Sticking a viewfinder on the accessory flash bracket of a Nikon F or F2 is how it used to be done when mounting the 2.1cm O-Nikkor, or anything wider, for that matter, which didn't clear the mirror. As for parallax, that's not an issue, especially if you're sticking it atop the prism. The "precision" of a 21mm viewfinder is so lax that you probably can't even measure the difference between error of viewfinder parallax and what the lens covers. The placement of your pupil in the viewfinder affects this more than where the finder is on the camera.
As for out of focus in the SLR viewfinder, I think only up close does this become an issue. Past about 10 feet, everything is in acceptable focus, especially for composition.
Go forth and have fun with it.

Phil Forrest
 
I have the Nikon 2.1cm finder for the accessory shoe of the F. It is a bit on the squinty side, not for use with eyeglasses. I also have the TTL viewer for the 2.1cm mirror-up lens.
 
I have a split screen SLR (P3n) that is the only SLR I can focus my 20mm lens with. I also have an external rangefinder. I like your idea I'm going to use it with my other SLRs. The only problem I see is the distance scale on the lens is pretty general, not like a rangefinder lens.
 
Danny D said:
When you look through the viewfinder of an SLR, while zone focusing, pretty much everything is out of focus. There is the depth of field preview lever of course, but this kind of defeats the object of zone focusing: putting the camera to your eye and very quickly snapping a shot off.
Click to expand...

I have a FM2 with 20mm 3.5 on my desk right now, if anything it is the opposite and hard to focus because so much is already sharp.
 
Mirror-up operation on standard Nikon F requires wasting a shot- the mirror stays up after the shutter is released. Celestron modified Nikon F bodies have a separate button added to release the mirror before the shutter is released. I'm not sure how many of those were made, but I have 3 of them. They are good for the 2.1cm Nikkor.
 
With lenses of 28mm and wider, I don't typically focus on a subject; I set a zone of focus using the DOF (depth of field) scale on the lens. So, an accessory rangefinder wouldn't be useful to me.

In the case of true wide angle lenses that require MLU (mirror lock-up), I can understand the use of a separate viewfinder.

- Murray
 
Danny D said:
When you look through the viewfinder of an SLR, while zone focusing, pretty much everything is out of focus. There is the depth of field preview lever of course, but this kind of defeats the object of zone focusing: putting the camera to your eye and very quickly snapping a shot off.

I have a voigtlander briteline finder on the way now. Also, I'm curious about why you'd have an actual rangefinder on an SLR? To go with an Nikon E grid screen I suppose?
Click to expand...

I'd just set the focus and look through the viewfinder, ignoring that much of it is out of focus. If your selected zone is about right, everything on the sharpest plane of focus will be sharp enough anyway.

I have 21mm optical finders. Never saw the need to put one on any of my SLR or EVF cameras, and I scale focus/focus by zone a lot of the time.

G
 
I suppose one advantage of using the brightline finder on an SLR would be the ability to see what's just entering your field of view, but is still outside the frame lines. This could be of some advantage in fast-changing situations such as street shooting, and is one of the oft-touted benefits of shooting with a RF camera. Personally, I've mostly found that advantage to be theoretical. YMMV.
 
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