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Tele Lens Attachments...help please
Old 02-14-2019   #1
Larry Cloetta
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Tele Lens Attachments...help please

Recently purchased a “tele lens attachment” for an Aires rangefinder, which turns the 4.5cm normal lens into an 8cm lens, in effect. Bought it for the distinctive resulting rendering, not because I needed a telephoto per se.
It screws onto the front element of the normal lens. People are using this setup with adapters on Sony digital bodies.
I will be using this on the Aires. My question is, how do you focus with this on a film rangefinder? Just align the rangefinder patch as normal, and use, say, an 85mm viewfinder for framing? Which is what my intuition tells me. Or do you have to scale focus because the rf won’t be correct?
My optics theory obviously is lacking, though this should be simple. I tried Google, but Google has no idea.
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Old 02-14-2019   #2
michaelwj
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Quote:
Originally Posted by Larry Cloetta View Post
Recently purchased a “tele lens attachment” for an Aires rangefinder, which turns the 4.5cm normal lens into an 8cm lens, in effect. Bought it for the distinctive resulting rendering, not because I needed a telephoto per se.
It screws onto the front element of the normal lens. People are using this setup with adapters on Sony digital bodies.
I will be using this on the Aires. My question is, how do you focus with this on a film rangefinder? Just align the rangefinder patch as normal, and use, say, an 85mm viewfinder for framing? Which is what my intuition tells me. Or do you have to scale focus because the rf won’t be correct?
My optics theory obviously is lacking, though this should be simple. I tried Google, but Google has no idea.
It shouldn’t change the focal distance and the RF should still work. The Tele attachment is just effectively a magnifying glass in front of the normal lens.
If you think about it, if the RF was no longer accurate then the distance scale on the lens would no longer be accurate (they are “coupled”), so you wouldn’t be able to scale focus.
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Old 02-14-2019   #3
peterm1
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As an aside I have always had the hots for this attachment on a Retina rangefinder. A Retina Longar Xenon C - f:4/80mm Schneider Kreuznach

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Old 02-14-2019   #4
Larry Cloetta
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Thanks, you guys are better than Google. I wasn’t sure if I was over-thinking this, or under-thinking it.
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Old 02-14-2019   #5
Sarcophilus Harrisii
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Larry,
Does the attachment feature a dual scale ring by any chance?

Unlike a dedicated Tele lens that can be calibrated or cammed to the integral rangefinder, the accessory attachments are altering the distance at which the basic lens focuses to, at any particular point of its focus travel. Meaning the rangefinder and combined lens will diverge.

Typically a dual scale will be incorporated into the better ones. The drill is therefore to rangefinder focus on your subject as usual, note the distance set according to the standard focus scale of the basic lens, and then check the accessory lens for the correct adjusted distance to achieve actual focus with the attachment in place. Ie the attachment scale is a calculator or compensation guide—you tweak the focus to the suggested distance with the Tele in place that is shown opposite the figure you initially got using the rangefinder, and this brings the combined rig back to sharp. It's a two stage focus. Hope this makes sense? 3.15am here so I'll check in later.
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Old 02-14-2019   #6
Sarcophilus Harrisii
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I can do a couple of quick pics of the dedicated Fujica Tele lens I have for my 35-EE RF tomorrow, if it helps. Cool unit that looks impressive. Not a fabulous performer wide open, of course, but makes up for that in sheer presence...
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Old 02-14-2019   #7
Larry Cloetta
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Quote:
Originally Posted by Sarcophilus Harrisii View Post
Larry,
Does the attachment feature a dual scale ring by any chance?


Typically a dual scale will be incorporated into the better ones. The drill is therefore to rangefinder focus on your subject as usual, note the distance set according to the standard focus scale of the basic lens, and then check the accessory lens for the correct adjusted distance to achieve actual focus with the attachment in place. ......
Hope this makes sense? 3.15am here so I'll check in later.
Cheers
Brett


Brett, that all makes sense, and it seems the attachment in question is not one of “the better ones”. So, I now understand how to use one of the better ones, but how did people focus the not-better-ones like my new not yet arrived one on a rangefinder? Not an issue with an adapted lens on a digital body. That might be the easy way out, if Aires to anything adapters were common, which they aren’t.

Maybe there were printed tables one carried around with conversion distances you could use after reading off the value on the distance scale on the lens? Something like that isn’t in the manual for the body, which in itself isn’t easy to come by.

Thanks for your help!
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Old 02-14-2019   #8
Sarcophilus Harrisii
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Quote:
Originally Posted by Larry Cloetta View Post
Brett, that all makes sense, and it seems the attachment in question is not one of “the better ones”. So, I now understand how to use one of the better ones, but how did people focus the not-better-ones like my new not yet arrived one on a rangefinder? Not an issue with an adapted lens on a digital body. That might be the easy way out, if Aires to anything adapters were common, which they aren’t.

Maybe there were printed tables one carried around with conversion distances you could use after reading off the value on the distance scale on the lens? Something like that isn’t in the manual for the body, which in itself isn’t easy to come by.

Thanks for your help!
Page 20 of this instruction manual (page 23 of the pdf file) suggests I am on the right track with my previous comments. But also raises more questions, as it does indeed refer to a calculator or compensation scale ("...set the triangle on the telephoto focusing scale..." ) that provides the adjusted setting for the main lens scale, so where is it? Perhaps there was a table supplied for use with the attachment?
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Brett
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Old 02-14-2019   #9
Larry Cloetta
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Thanks, Brett, now I understand. The manual you show was for the Aires Viscount, which was a later (and purportedly less good) model than the Aires 35-V I have. The section in the manual you referred to was not in the 35-V manual I had. The reason for that, as I am coming to understand, is that the tele lens can be attached to, but can't be focused on the lens on the 35-V.
The tele attachment was apparently made in conjunction with the Viscount, as Aires redesigned the lens/shutter assembly for the Viscount specifically to allow the use of the tele attachment.
Take a look at the lens on the Viscount, at the ring next to the body (picture below). There is the triangle referenced in the manual, next to the word “tele”. So, this setup does have a dual scale, they just implement it differently, the scale is on the main lens, not the attachment.
I learned something. Now, since I can’t use this attachment on the camera I have, I either need to get a Viscount, or get an adapter for a digital body, which might make more sense at this point. Although Viscounts are easier to come by and cheaper, than the adapters.
Thanks again, Brett, I doubt I would have figured this out without the help of those here.

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Old 02-14-2019   #10
Sarcophilus Harrisii
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Welcome Larry!
Although it would be tedious, I suppose you could use a ground glass to plot the correction needed every five or so feet of focus distance to manually compensate the focus for the camera model you have. Given that these additional lenses tend to only perform well closed down a few stops anyway absolute precision beyond fifteen feet is not essential, as there will be a DOF buffer. But I can absolutely see why you may prefer to procure Eg. a Viscount to make things easier.
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Brett
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Old 02-14-2019   #11
zuiko85
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Watch that thing carefully and always support its weight. It's a lot of stress on the regular lens hanging on the filter threads. I've seen front filter thread rings or whole front lens groups loosened or broken off by these contraptions.
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Old 02-15-2019   #12
Doug
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I have my Dad's Petri 7S with the tele and wide attachments and aux viewfinder. Both the lens attachments have focus adjustment scales. The user focuses normally then reads the distance off the main lens distance scale and manually resets the distance on the lens according to the translator adjustment scale. As Brett earlier explained!
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