Bausch & Lomb 506mm 5.6 / lens coverage for 16x20

[maxi0909]

It's the magnification. 1:1 means the image projected is the same size as the actual person/thing in the photograph. Thank you for mentioning your intended photographic subject. Now, consider how exactly you want to photograph them (full-body, environmental, headshot, etc.) and then see how that compares to the magnification of the lens you are considering. 1:2 would be half life-size, btw.

I want to make headshots... i saw a dude who did that and the picture on the plate was life size... maybe this is what i want? 1:1 ?

so i can buy this lens for that type of use?

It´s very hard, because those other people tend to use highly expensive lenses

[Dan Fromm]

Dan,

I have the Telephoto lens in question. Mine came on a weird Leica threadmount mirror-box thing. Was a freebie with a Leica III I bought through an estate.

It illuminates 8x10 easily. I haven't shot it on 8x10...no shutter, and no reason to do such a crazy thing. But, I wouldn't hesitate to do so. And as we both know, focused close it would cover more. If the OP wants to shoot 16x20 portraits at 1:1 it would be reasonable to think the B&L could do what he wants, especially if a little vignetting and/or poor corner resolution is okay. He hasn't told us his objective.

Whatever it was rated for via the USAF is indicative of just one use-case.

Bryan, I thought I hedged.

The OP asked about 16x20, didn't say anything about application. 8x10 is large, 16x20 is, alas, larger.

[Dan Fromm]

Fairchild K17 shutter would be the one.


Bernice

Interesting. I ask because I don't know. Can those monsters be operated manually when the lens isn't mounted on the camera it is intended for?

[Dan Fromm]

I want to make headshots... i saw a dude who did that and the picture on the plate was life size... maybe this is what i want? 1:1 ?

so i can buy this lens for that type of use?

It´s very hard, because those other people tend to use highly expensive lenses

Measure heads. Will 8x10 do for the shots you have in mind? Will 16x20?

You said plate. Did you mean glass plate, wet or dry, or are you thinking film?

Early in this discussion you mentioned small digital and a fast 50 mm lens. Do you want to make portraits with tiny depth-of-field?

I directed you to the list and lens catalogs so that you can find lenses' rated coverages. Makers usually use the coverage concept "puts acceptable quality image in the corners." Some people here use the concept "puts light in the corners." If the shots you have in mind will have little or no fine detail in the corners then the second concept is better for you.

The list has short reviews of books on close-up work and of books on LF photography. You'll learn more, and more quickly, from books than from short posts on a bulletin board. Buy some books.

Long lenses with high coverage tend to be very expensive. One way to get coverage is to use a relatively narrow angle lens that's longer than normal and stand back a bit from the subject. That's what the guys who do full body portraits on huge negatives do. Look for Richard Learoyd for examples and, perhaps, inspiration.

[Corran]

Listen to what Dan says. Before you can shoot 16x20 well, I think it would be good to understand how to shoot 8x10 well (the largest format that is relatively "easy" to find usable cameras and lenses for, and relatively inexpensively. Notice my liberal use of "relatively!").

Don't jump into the deep-end headfirst and blind, basically. Perhaps find someone near you who can get you hands-on with ULF.

[Bernice Loui]

Correction, that would be a Fairchild K38 shutter. It is HUGE and the shutter blades can slice off a finger. Yes, the K38 shutter can be operated stand alone. There is a wind up shaft then a shutter release spigot, think it has three shutter speeds. At one time there was a YouTube video of a K38 shutter's operation. Have one of these in the pile with a 12" f2.5 "hot" Aero Ektar. Might dig it up then re-do that video showing it's operation.


Bernice

Interesting. I ask because I don't know. Can those monsters be operated manually when the lens isn't mounted on the camera it is intended for?

[maxi0909]

Listen to what Dan says. Before you can shoot 16x20 well, I think it would be good to understand how to shoot 8x10 well (the largest format that is relatively "easy" to find usable cameras and lenses for, and relatively inexpensively. Notice my liberal use of "relatively!").

Don't jump into the deep-end headfirst and blind, basically. Perhaps find someone near you who can get you hands-on with ULF.

Guys please, we can talk about jesus and the world later..

I already shot 4x5... i need to shoot 16x20 because it is a project for the university... large portraits on glass with wet plates (i did this on 4x5)

Can you please answer me this small question because the offer someone did to me will run out soon /:

Will the Zeiss apo tessar 640 f10 24" work for only close portrait shots or not? Nothing more

Please HELP me

[Corran]

Dan and I have already given you the answer. At 1:1, the spec sheet says it will cover 25 x 21 inches sharply. So at 1:1 magnification, a.k.a. life-size, it will do what you want. At less-than, it might not.

I trust you can handle the rest.

Caveat: I don't own the lens or shoot 16x20, so my opinion is based on the posted spec sheet and nothing more.

[fuegocito]

Since you have the said lens already, you can stick it through a black out window, and make a 1620 white cardboard and line up the projected image till sharp focus is achieved to see if it covers the whole board. I have the exact lens and I have mounted to my 11x14 and it certainly illuminates the entire field sharply at infinity.

[Mark Crabtree]

Guys please, we can talk about jesus and the world later..

I already shot 4x5... i need to shoot 16x20 because it is a project for the university... large portraits on glass with wet plates (i did this on 4x5)

Can you please answer me this small question because the offer someone did to me will run out soon /:

Will the Zeiss apo tessar 640 f10 24" work for only close portrait shots or not? Nothing more

Please HELP me

Of course. Go for it, and have fun. You won't find a lot of 20" or longer, normal design (non-tele), lenses that won't cover at 1:1.

There are a few other things to keep in mind when choosing your lens, though, that you might already know, or might have been mentioned here even, but worth a reminder - For head and shoulders portraits on this format you will be at 1:1 or higher magnification (closer). That is a handy reference point to use.

At 1:1 you will need to extend the lens about double its focal length, so 48" for a 24" lens. Depending on the lens design and mounting, that will generally require just a bit less than that amount of bellows. Your subject will also be about 48" from the lens. So about 8 feet from the focus point of the subject to the ground glass. Add in some distance for the depth of the subject, to the background, and room to step back to view on a 16x20 ground glass. I can do it on 11x14" in my 15 foot shooting space, but more would sure be nice. This is one aspect where higher magnification is handy since you need less shooting space. Also, obviously, longer lenses need more space. I can't shoot all that much looser than 1:1 with 24" fl in my space.

At 1:1 your lens is effectively 2 stops slower, so an f11 aperture is working like f22. I use window light and find that way too slow for me. F6 is as slow as I like. Outdoors, or with enough light your options are greater.

Good luck with your project. I hope you'll post your progress.