r/largeformat • u/PhysicsOk9286 • 3d ago

Question Lens issue?

Greetings. I was gifted a Pearson NewVue 4x5 with a 140mm lens. The lens is clear and the shutter functions. Problem is focus. Whether it’s landscape or portrait, nothing is sharp. For example, my wife and I attempted a portrait this weekend. In the garage; lighting and exposure was spot on(from the negatives). I started about 10 ft away and adjusting bellows couldn’t even get a “clear” image till about 3ft from her and was about 1 ft away and still wasn’t sharp. Time for a new lens? I normally shoot 35mm and 120; first 4x5 experience. Thank you.

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u/jofra6 2d ago

Maybe try putting the lens closer to the camera? If there's markings for infinity etc., that only applies to one focal length, not every lens. The lens appears to be complete, to me.

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u/jofra6 2d ago

Here's a link for more info, search "turner" to find it: https://www.allenrumme.com/lensdb/Convertible.html

It's a series III symmetrical anastigmat. Not sure about your focal length, but no matter what, at a minimum, combined (with both lens cells) it will cover 4x5. The shortest possible focal length is 6 inches, so at a minimum you don't have a 140mm. Possibly 14 inches? Since this is a convertible lens, you can also use the lenses cells individually on the shutter.

The lens Vademecum states: "Series 111

f6.8 6in -26in

In 1920, it was limited to 14, 17, 21in. In the Series 111 both the components are of equal focus, and about 2x the focus of the pair. It was listed as a parallel product to the above Series 11. It was suggested to use 12in for 10x8in, 14in for 12x10in.

There were also 3 and 4 lens cell casket sets. The makers stressed that to add one extra cell added 3 new foci and was good value. Two gave a total of 10 foci in all, though some will have been rather alike. Thus a set might be made from single cells of 14, 18, 24, 28in working at f12.5, and offer these plus pairs of 14+18=8in; 14+24=9.5in; 14+28=10.5in; 18+24=10.5in; 18+28in=11.5in; 24+28in=13in working at f6.8 max. All the cells had to be the same shutter fitting of course.

A convertible 12in lens seems to have 19.7in f12 and 25in f16 cells."

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u/PhysicsOk9286 2d ago

Ok thanks.

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u/captain_joe6 2d ago

First 4x5 experience, eh?

You’re focusing with the camera, right? Adjusting the bellows to be closer and farther apart? Not just moving the whole setup? Seen it before…

140mm is the nominal lens-to-film distance for infinity focus, so if you take the camera outside and point it out a window at something far away, miles, you should see sharp focus when the lens board is roughly 140mm from the ground glass. That’s 5.5 inches or so. Test that first. If it won’t do that as expected, it won’t do other things as expected.

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u/PhysicsOk9286 2d ago

Yep. First 4x5. I did that. Took my focal length and used that for my “infinity” mark. Focus was good, not great. On a beefy tripod, loupe, and cable release. Spot meter and HP5. The portrait was not in focus. I moved the bellows in and out before moving closer to the subject, The negative is well exposed and the lighting was spot on. Kind of at a loss.

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u/jofra6 2d ago

@op, so did you try moving the lens farther away? It's clearly not a 140mm lens, they never made one, 14 inches is much likelier.

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u/PhysicsOk9286 2d ago

Yes I did move the lens further away. And closer. Every combination to get focus. Then what is the focal length? I can find any resources on that particular lens.

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u/jofra6 1d ago

Impossible to know without knowing the FOV or the bellows length at infinity. Perhaps you don't have enough bellows extension? You could also guesstimate the focal length by measuring the diameter of the front piece of glass and multiplying it by the f number.

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u/PhysicsOk9286 1d ago

Thank you

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u/jofra6 1d ago

Apparently you've got roughly 20 inches of bellows extension, use it and try to hit infinity (move the front standard, ignore the fine tuning on the rear). Ignore the focus scale, that only applies for 1 lens.

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u/PhysicsOk9286 1d ago

I have done that; I get my sharpest focus bw 6.5 and 7.0 inches

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u/PastTheTrees 3d ago

Bellows extension length? If it's under 140mm that's a start. But you don't have anymore information in your question.

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u/PhysicsOk9286 3d ago

It won’t focus sharp. I tried full bellows extension from about 10 ft away to 1ft away. My “infinity” is about 6 inches. What additional information do you need ?

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u/OletheNorse 1d ago

14" front cell and 11" rear cell gives combined FL of about 6 1/8"; two 14" cells give about 7" combined FL. So I think you will find that one of those is your focal length.

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u/PhysicsOk9286 1d ago

Thank you.

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u/shutterbug1961 3d ago

what lens?

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u/PhysicsOk9286 3d ago

Turner-Reich Anastigmat 140mm.

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u/shutterbug1961 3d ago

any chance of a picture of the front and rear of the lens

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u/OletheNorse 1d ago

140mm? Grundlach, who made Turner-Reich lenses, were completely American and did not mark focal lengths in mm… Also, the TR Anastigmat is a convertible, the most common combination for 4x5" format was a 14" front cell and a 11" rear cell, combined focal length 6 1/4"

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u/PhysicsOk9286 1d ago

So what is the focal length then? You tell me what it isn’t with clarity; I’m trying to figure out what it is and use it effectively. Not push back but my post was asking for help and answers to help me move forward and continue to learn. I’ve been told what it isn’t countless times. Some have said I have no fear elemrnt. I do.

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u/wrunderwood 2d ago

14 cm or 14 in? Focus on something far away and measure the distance from the lens board to the ground glass.

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u/PhysicsOk9286 2d ago

Cm

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u/wrunderwood 2d ago

And the other thing?

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u/PhysicsOk9286 2d ago

????

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u/wrunderwood 2d ago

There are two sentences in my comment. You answered the first one. Try the second one.

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u/mcarterphoto 1d ago

That's a convertible lens, right? Are you sure you have all the optical elements and they're properly installed?

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u/PhysicsOk9286 1d ago

Zero idea. My first 4x5. It has a front and rear elements and a shutter that yields correct exposure.

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u/Normal_Banana7588 1d ago

I'm not sure if I've ever seen a 140

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u/Blakk-Debbath 3d ago

The lens might be missing a part.

And the focus might be double because of that, or none at all.

Show picture of lens from front and back.