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Frank Petronio
11-Jan-2009, 22:13
Going off-topic on the Littman Polaroid 110 thread, people were discussing building a camera similar to a 110 only using better materials and specifically for 4x5 film.


I'd think you would want a larger rangefinder in order to be more accurate?

Perhaps the simple, compact, light, cheap thing to do is to not have a built -in rangefinder and use a shoe-mounted separate one instead (like an early Leica did). It would allow you to have different scales mounted to the rail for each lens, and the moment spent transferring the rangefinder distance to the focusing against the rail mark would be minimal anyway.

Might be time for a new thread rather than continuing here....

Just wondering what would be the best practical "off the shelf" rangefinder to use for a scale focusing camera? One of the old 1930s Leica ones? Or perhaps a modern electronic golfer's rangefinder? Or ?

Greg Lockrey
11-Jan-2009, 22:18
I have a Fotoman RF that I got for about $100 that is very small and seems to be very accurate that fits on a hot shoe of a camera. (I use mine with an old Rollei 35 that I had for a number of years).

David A. Goldfarb
11-Jan-2009, 22:26
I have one from an obscure company called Widor that's easy to calibrate with two adjustment screws that are accessible without disassembly, and it has been fairly accurate for 6x6cm and 4x5". When I had a Linhof Tech II for a while, I set it up just as you suggest, with the auxiliary finder (the camera had an accessory shoe that may not have been original) and scales for different lenses taped to the bed.

I looked into the golf rangefinders once, and they are very fancy and expensive optical devices, but the ones I saw weren't calibrated for photographically useful distances. Golfers want to know how far they can hit the ball, and they're probably a little embarrassed if they have to measure distances like 3 or 6 feet.

Oren Grad
11-Jan-2009, 23:05
I have a vintage rangefinder buried away that I haven't fiddled with in a while - as I recall, it's a Voigtlander. At any rate, the current equivalent is the Fotoman rangefinder that Greg mentions. For anyone who's not familiar with the Fotoman product, you can see it on this page:

http://www.fotomancamera.com/accessories_list.asp

I'm skeptical about read-and-transfer, at least for my purposes. Where I really want the focusing help is in situations where just taking my eye away from the finder and waving the camera around to transfer settings is going to be enough to throw everything out of whack. It's tricky enough with a Graphic, or a cammed Horseman or Linhof, where you don't need to transfer settings but you do need to move your eye from RF to VF after focusing.

The combined RF/VF is one really nice thing about the Razzle.

Arne Croell
11-Jan-2009, 23:18
As David says, the golf rangefinders ( at least the ones I've looked at) do not work within "putting range"; on the other hand, they are more accurate than needed for long distances. The "electronic tape measures" made by several companies, also using lasers, have the opposite problen in that they usually end at 30m, 100ft or similar ranges. It should be possible to combine both approaches in one instrument, but I haven't seen one. The classic optical rangefinders using prisms or mirrors still seem to be the best option. There, anything with a larger effective baseline than the 110B should be more accurate. I recently bought one with a 15cm baseline made by a former US subsidiary of Hugo Meyer, Meyer-Opticraft, in the 1950's or 60's; much longer than the usual Leica-sized ones. Its quite accurate. Military surplus would be another venue to look for rangefinders.

Frank Petronio
11-Jan-2009, 23:31
Oren, yes the coupled RF/VF of the 110 is nice but the problem with that one is it is not that accurate up close at the portrait distances you would want the coupled RF/VF for!

I hadn't seen the Fotoman site in a while, they have really matured, thanks for pointing me there. More GAS.

Is it easy to calibrate -- i.e. you don't have to disassemble I take it?

Arne - If the electronic RF is good to 100 feet, couldn't we estimate from 100 feet to infinity pretty well?

Oren Grad
11-Jan-2009, 23:53
Is it easy to calibrate -- i.e. you don't have to disassemble I take it?

http://www.fotomancamera.com/download/2007273347RangefinderManual.pdf

I was amazed to read in the other thread that Gordon's working seriously on this. It's quite a challenge, but more power to him!

Leonard Metcalf
12-Jan-2009, 02:47
I use one of the fotoman rangefinder all the time, I find it easy to use and very accurate. (On my Fotoman 45PS)I don't ever seem to have problems focusing the camera, even when I guess (it is nice having a hyperfocal scale on the helical focusing mount).

My single biggest issue is with the accessory viewfinder. I have cut off so many things, by thinking that the sides would be accurate even if the heights had parallax error. Again I could see the advantages of a coupled rangefinder here.

Len

Arne Croell
12-Jan-2009, 05:32
Arne - If the electronic RF is good to 100 feet, couldn't we estimate from 100 feet to infinity pretty well?

It depends on the focal length - it could certainly be done for wide to normal lenses. Here is one of those, actually now
goes to 130ft: http://www.boschtools.com/Products/MeasuringAndLayout/Pages/BoschProductDetail.aspx?pid=DLR130K

One downside is that the bulk and weight is about 3x that of an optical rangefinder, and they project a red dot of laser light. If used for portraits you want to make sure not to hit the eyes of your subject.

The upside is that you can also use it for its intended purposes in home improvement projects.

rknewcomb
12-Jan-2009, 06:13
My single biggest issue is with the accessory viewfinder. I have cut off so many things, by thinking that the sides would be accurate even if the heights had parallax error. Again I could see the advantages of a coupled rangefinder here.

Len[/QUOTE]

Do you frame subjects tightly?
Do you think the finder frames for the various lens are off?
This worries me as I was thinking about getting one of the Fotoman finders.

Thanks.

Frank Petronio
12-Jan-2009, 06:33
The couple of successful advertising (i.e. prosperous) landscape specialists I knew of used the Linhof Panoramic 612 and 617 with a ground glass back in order to get things "perfect". I never understood why they just didn't bring a 4x5 field camera out to get the same shot with more cropping options and less PITA than not breaking a separate ground glass attachment?

Point being that they wouldn't rely on the viewfinder for something critical.

Even on my lowly Crown, the viewfinder is OK for about 75% of the scene depending on distance. Up close I would try to allow a healthy margin -- maybe 20% or "an inch out of the 4x5 frame" -- to make sure I got the shot. The Linhof was a little better because you can adjust it for distance.

John O'Connell
12-Jan-2009, 12:20
The coupled RF/VF on the Polaroid 180 is pretty accurate close up, and Polaroid made close-up and portrait kits for it.

I probably should save up and send my 180 to Australia at some point . . .

Leonard Metcalf
13-Jan-2009, 01:48
I have the older finder, which has apparently been upgraded by fotoman. The newer model has the mask closer to the eye. They apparently have an upgrade system, which I will shortly undertake, and let you know how the new one goes. I suppose I am used to framing accurately on the ground glass. So yes I frame tightly, and am learning not too. I am also shooting a 135mm lens. I have been considering picking up a linhof multi finder, which I know has the ability to cater for parallax by dialing in the distance.

Regards,

Len