What focal lengths for standard finder on LTM camera

I'm a bit confused about lens focal lengths and RF compatibility on a

screw mount camera like my IIIc. Is the built-in RF only good for

50mm lenses? Is a special finder required for longer or shorter

focal length lenses?

 

If I mount a 35mm lens on my IIIc, will I still be able to focus it

accurately with the built-in finder? What about a 90mm or 135mm

lens? Do you have to mount an auxilliary RF every time you use a

focal length other than 50?

Yes, the viewfinder (VF) on your IIC only has the 50mm view & you will need special finder(s) for anything shorter or longer. You can *focus* non-50mm lenses w/the RF (rangefinder), but the VF will only show the 50mm view.

You can focus accurately regardless of lens focal length, as long as it is a rangefinder-coupled lens (most leitz lenses). However, the FRAMING will be off, because the view portrayed by the built in viewfinder is that of a 50mm lens. This is why you get an external viewfinder, for composition, not for focussing.

Skip, the answer is YES to each of your quesstions. :-)

<p>If you end up wanting one or more accessory finders, you might start

by reading <a href="http://www.cameraquest.com/leicafin.htm">this

page</a>.</p>

To add a little to the former comments. The viewfinder of the IIIc roughly diplays the view of a 50mm lens at 3 meters and about 90% of the view at infinity. You will have to correct for parallax and reduced view angle at shorter distances.

 

The rangefinder on the IIIc is independent and will focus any RF coupled lens.

 

Cosina makes three excellent and affordable viewfinders for 35mm under the Voigtländer brand, or you can use any of the dozen classic finders for that focal length. I use a Soviet one made by Arsenal or a Kiev turret copy of the Contax.

You seem a little confused about your camera's finders. The VIEWFINDER is the window closer to the accessory shoe; it shows the entire view that will be on your negative if you use a 50mm lens. It works only for ALL 50mm lenses. The RANGEFINDER is the window near the rewind knob, which shows an enlarged image, to focus the lens. It works for ALL rangefinder coupled Leica lenses, regardless of focal length.

Ok, I was more confused than I thought! Thanks everybody. I've got it now. As long as it's an RF-coupled lens, the rangefinder on my IIIc will allow me to focus the lens. I need a viewfinder that is compatible with the lens focal length to show me the proper field of view.

 

I haven't actually used my "new" IIIc yet. This is the one that I got at a garage sale for $1 that I mentioned in a post about a week or so ago. I sent it to Youxin Ye for a CLA and to have the vulcanite replaced with new a leatherette cover, and he got it back to me in less than a week. It looks great and operates smoothly. Unfortunately, my 5cm Elmar is still with Sherry Krauter, so I'm unable to use my camera. I was thinking about buying another lens in a different focal length, maybe 35mm, and I was just trying to figure out what else I'd need to use it. And apparently that would be an accessory viewfinder, assuming that I find a 35mm lens that is RF-coupled.

Get a CV 35mm, super lens (they all are) and see previous post for VF.

I would like to infuse a bit of heresy into this discussion for which I will probably incur some flaming. Most of the concern about viewfinder coverage is attributable to the expectation of accurate framing associated with SLRs. The fact is that though SLRs are much more accurate in the framing department, very few of them afford the accuracy expected. Nikon is the exception, particularly the F series and can be depended upon to satisfy the most demanding user. However, that degree of accuracy is only expected by those who eschew cropping and consider framing to the exact 24 x 36 format as gospel. To the rest of us who employ after the fact cropping as a standard procedure there are measures that can be used to produce successful shots with a minimum of investment in auxiliary viewfinders. <p> The multifinders are well covered by Gandy and will not be addressed in detail. Suffice to say that unless you prefer bright-lines, the Arsenal (Russian), Tewe, and Nikon finders do a great job for anything other than the more extreme wide angle lenses. The latter two are zoom finders that can be adjusted to any in between focal lenghts that might be encountered. <p> To many of us on the other hand, the mounting of any auxiliary finder is a PITA and contradicts the original intents of the miniature camera as perceived by Barnack, when he laid down maximum dimensions that were generally honored at least until introduction of the M series of cameras. <p> Here are a few tips and tricks that will enable a resourceful user to employ various focal lengths in the absence of dedicated view finders. <p>

Barnack cameras: <p>

∙ The RF field (though round) defines the approximate width and height of the field of the 135mm lenses. <p>

∙ The field of the 90mm lenses is half the width and half the height of the field shown in the standard viewfinder. <p>

∙ The 50mm frame covers approximately 75% of the width and height of the 35mm frame & 50% of the height and width of the 28mm frame. <p>

I've been using an IMARECT finder on my IIIf for over 50 years, and an quite happy with it. They are often on eBay and quite inexpensive (especially for a Leica product). They're good for 35-135mm lenses, and give extremely accurate framing.

Harry, I could probably manage the longer lens with the 50mm VF in a pinch, but going wider than 50mm sounds like it would be considerably more bother. It does seem a bit inconvenient to have to put an auxilliary VF gizmo up on top of the camera.

 

Bill, I've got my eye on a couple of IMARECTs now on Ebay. Thanks for the tip.