View Full Version : Anyone know the right lens for 2:1 reproductions on a 10" x 8" camera?

Danny Treacy
30-Jan-2007, 09:58
If anyone could advise me on this that'd be great; I've been using my standard (360mm) lens on my 10" x 8" to get 1:1 - 2:1 reproductions of 3-D objects around 7" tall, I'm finding it a real pain to accurately use movements and even focus due to large bellows extension (I can play a tune on it though, it's as tight as a drum). I've found my sweetspot so it's not that that's a sharpness problem, it's due to light being lost in bellows, so if anyone knows of a good macro lens for 10" x 8" (I'd like to avoid buying an expensive new one). Thanks.

Joe Forks
30-Jan-2007, 10:36
try a 150mm lens with 600mm of bellows extension and see how that goes. You'll have a long exposure - 360,000/22,500 = 16x the indicated exposure.

on the other hand, an object 7" tall at 2x life size is 14" tall and you only 10" of film height on the verticle. I might be missing something, but how you gonna do that?

Richard Kelham
30-Jan-2007, 10:44
If you are shooting at say 1:1 ratio then the bellows are going to be stretched to twice the focal length of the lens. If you use a lens of say 200mm FL then the bellows stretch will be less of a problem, but you will still be losing 2 stops worth of light.

There are shed-loads of old but good process and repro lens out there which would be ideal for your purposes. Some might even have shutters. A few might even allow you to reverse them. They do tend to be rather slow lenses, typically max aperture of f9...perhaps you need brighter lights?:)

That's my tuppence worth. Stand by to be deluged with more advice.


Danny Treacy
30-Jan-2007, 10:47
Thanks but I tried it already with the 150mm off my Linhoff 5 x 4, it worked ok but I use reflected light to illuminate my objects and therefore need to have reflectors either side and near the front of the object, I found that the 150mm was so close it prevented me being able to use such reflectors.

I did state that my reproductions are 1:1 - 2:1, nice try at being smart though!

Danny Treacy
30-Jan-2007, 10:50
Thanks Richard, the explanation of the maths helps. I think the F:9 may be a bit of a problem, also I polarize the lights which doesn't help!

David A. Goldfarb
30-Jan-2007, 10:57
Then do you have a 210mm or something thereabouts? This is always going to be a tradeoff--a longer lens gives you more working distance for lighting but also requires more bellows. It's just a matter of finding a happy medium.

As far as bellows exposure factor goes, this will be the same no matter what lens you use, as long as the magnification stays the same. A shorter lens doesn't get you a brighter groundglass image, unless it also happens to be a faster lens.

If you want a faster lens for composition and focusing, maybe something like a 210-240mm Tessar or Xenar would do. They're usually around f:4.5 and not too costly, and at this magnification should be pretty sharp.

Joe Forks
30-Jan-2007, 11:00
sorry, I really wasn't trying to be smart.

besides the 360, which other lenses do you already own?

Danny Treacy
30-Jan-2007, 11:08
I only own a standard for 10 x 8 and a standard and wide for 5 x 4, I'll check out Tessar and Xenar on ebay, I had looked into G-Claron and Apo-Ronar but they all seemed to be around F:9, thanks for the advice.

neil poulsen
30-Jan-2007, 11:36
You might be able to rent something for a day. Can you borrow something from a friend, or is this something you intend to do on a regular basis?

Also, be careful about depth of field. Most calculations don't apply to close-up photography. Check it out on the ground glass with a penlight and small target or something.

Danny Treacy
30-Jan-2007, 11:53
Renting isn't really an option as it's something I'll be doing for a long time, thanks for the advice about depth of field, there's one of those calculator dial things on my camera, I thought I wasn't usuing it right but it must be due to the close up factor changing it. This Macro thing's starting to become a pain in the backside.

Ernest Purdum
30-Jan-2007, 16:39
Maybe temporarily removing the polarizers or otherwise increasing the illumination while focusing would help. I have sometimes used an extremely bright portable spotlight for focusing purposes.

Enlarging lenses are faster than the process lenses but made for use at closer distances than the Tessars and Xenars. They are also often available at relatively low cost. For the work you describe you can probably do without a shutter.

Ole Tjugen
31-Jan-2007, 00:57
Yet again I'll suggest an elderly 240mm f:5.6 Symmar. Make sure you get one in a #2 shutter though - then you can easily swap the lens cells around if you need to get even closer than 1:1!

A 240mm gives you 48cm bellows extension and working distance at 1:1. That's a lot easier to handle than your 72cm, yet gives more working room than the 30cm you get from the 150mm. F/5.6 is less than the f/4.5 of the Xenars and Tessars, but the Symmar is a lot better for close-up work.

John Kasaian
31-Jan-2007, 02:25
I've seen some slick work done with a 210mm Dagor

Danny Treacy
31-Jan-2007, 08:54
Thanks for all the advice, from what I can gather there's alot of pros and cons to each lens.

I've been looking on ebay and have managed to pick four lenses that have been mentioned, now the hard bit is deciding which one to go with.

So I'll list them and if anyone feels they could advise the best lens out of the bunch for producing 2:1 - 1:1 enlargements of objects around 7" on a 10 X 8 then I'd be very happy, here goes:

Schneider G-Claron 210/F:9

Schneider Symmar-S 240/5.6

Schneider Symmar 240/5.6 - 420/12 Conv

Siniron S 210/5.6 (Rodenstock Sironar N)

David A. Goldfarb
31-Jan-2007, 09:17
If you want a larger focusing aperture, I'd skip the G-claron for this purpose. The Symmar-S will be newer than the Symmar convertible and both should cover 8x10" at infinity, I believe, so that's a plus if you want a moderately wide landscape lens for 8x10".

The 210mm Sironar N should also be an excellent lens, similar to the Symmar-S in quality, is perfect for 4x5" tabletop work, and will cover 8x10" at 1:1 but not at infinity.

Ken Lee
31-Jan-2007, 09:48
Make sure you get one in a #2 shutter though - then you can easily swap the lens cells around if you need to get even closer than 1:1!

Which shutter types have front/rear threads of identical size ?

I was aware of the #0, and have been grateful for the info.

Bob Salomon
31-Jan-2007, 10:58
The 180mm Apo Macro Sironar is designed to do exactly what you are trying to do.

Ernest Purdum
31-Jan-2007, 10:59
The Number 1 has different size front and rear threads (usually, there are rare exceptions). The other modern standardized sizes and, as Ole points out, the long discontinued number 2 size, have the same threads front and rear. So do most, but not necessarily all, of the older shutters.

Why the number 1 is an exception beats me.

Danny Treacy
31-Jan-2007, 11:29
Thanks for the advice about the 180mm Apo Macro Sironar, unfortunately I can't find a 2nd hand one anywhere.