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Peter Chong
23-Jan-1999, 22:53
I am begining to consider LF, having used the 35mm format for more than a decade . My current system is built around the Canon EOS.

I am considering a 4X5 camera. Primary intention is to do macro work on watches (60%. I would need 2.5 to 3x magnification), some portrait (30%) and architectur al(10%).

Some threads in this forum seem to indicate that LF would not be the perfect for mat for large magnification closeups, due to bellows extension. But I am unclear .

I am considering either the Arca-Swiss Discovery or the Toyo 45C, and begining w ith just one lens: the Rodenstock Macro Apo Sironar 180mm. I understand this len s is useful to up to 3X magnification by interchanging the front and rear elemen ts. What belows extension would be required for 3X? Would my chances be better w ith the 120mm version of the same lens? How would you compare this to the Nikkor Apo Macro ED 120mm or 180mm alternatives?

Would the lens be good for my other intentions, vis a vis portraiture and archit ecture?

I am planning on getting a Sekonic 488 meter, a 6X loupe, the black cloth. I cur rently have a Benbo tripod, but will get a Bogen pan/tilt head for it. Would app reciate recommendations on tripod head. What other accessories would be recommen ded?

Thanks for the help. And for this excellent site.

Michael S. Briggs
23-Jan-1999, 23:27
The relevant equations are: 1/o + 1/b = 1/f, m = 1 / (o/f - 1), m = b/f - 1, where m is magnification, f is focal length, o is object distance (lens to object) and b is bellows length (lens to film). Be sure to measure f, o and b in the same units.

For m=3, f=120 mm, one gets b=480 mm (19 in) and o=160 mm (6 in). This bellows length exceeds the capability of some cameras. The object distance might be inconvenient, e.g., lighting the object without the camera getting in the way. For m=3, f=180 mm, one gets b=720mm (28 in) and o=240 mm (9 in). Very few cameras will permit such an extension.

For this one of work you will need a solid (heavy and/or precise) setup because of the long bellows extension and the long exposures. Otherwise vibration will obviate the advantages of going to large format. Exposures will be long, from the light being spread out because of the long bellows extension, the need to stop down for depth of field, and the resulting reciprocity correction. You might not even need a shutter! Unless you really pour the light on or use flash, exposures will probably be well over 1 second.

Other options: Schneider sells shorter focal length lenses (enlarginging lenses) in shutter. These would reduce b and o. They might make o too small. Or you could use a view camera to shoot medium format using a roll film back. These lenses have correspondingly smaller coverage. But at magnifications >= 1 this won't be a problem: the coverage of a lens (the largest image it can project) is double at 1:1 compared to the coverage at infinity.

Nikon, Rodenstock, Schneider all make macro lenses. The Rodenstock one calls for switching the elements depending on magnification. Most macro lenses are optimized for 1:1 but will perform well over a range of magnifications. Many use the G-Claron (which is optimized for 1:1) for infinity work. But with your high magnifications, you probably wouldn't want the G-Claron because it is slow (f9), versus one of the modern faster macro lenses.

In terms of choosing a lens, the boundary for designs for infinity work vs macro work is magnifications of roughly 0.1 or larger. In many cases one lens will work adequately at all ranges. But many macro lenses have smaller coverages than standard lenses, and so might not cover the film for infinity work, or if they do, not allow much movements. For architecture work you may find yourself wanting to use large movements. Ultimately, you might need two lenses. Start with one and see how things work...

Good luck.

Peter Chong
24-Jan-1999, 00:15
Thanks Michael.

Long bellows would be a great problem. I know this would cause extremely long exposures, especially if I need f/64 to get good DOF.

Would you think a Rollei SL66 (with 8 deg tilt, no rise/fall, shift, or swings) be more suitable?

thanks

Bob Salomon
24-Jan-1999, 00:21
Unfortunately you are being given incorrect information about our Apo Macro Sironar lenses.

1: These are optimized for 1:5 to 5:1 2: You DO NOT switch the elements on the Apo Macro Sironar series 3: The Apo Macro Sironar is available in 120 and 180mm.

4: The discontinued Macro Sironar series was the one where the elements had to be switched. For 1:3 to 1:1 the elements were placed as they were when the lens was first purchased. For 1:1 to 3:1 the elements were swapped. 5: The Macro Sironar was only available in 210 and 300mm. There never was a 180mm version in this series.

There is also a new macro from Rodenstock - the Apo Macro Sironar Digital for the same range as the 120 and the 180mm but for roll film and digital cameras. It is a 120m

Peter Chong
24-Jan-1999, 22:05
Dear Bob,

Thank you for your response. The information on the Rodenstock APO Macro Sironar was gathered from B&H's site

http://www.bhphotovideo.com/photo/large/lenses/macsironarn.html

I do see that the information in your website agrees with that in Rodenstock's...

However, isn't a 5X magnification impractical? From my calculations, this would result in a bellows draw of 1080mm! And would require an Exposure Compensation Factor of 36! Did I calculate wrong?

Would appreciate more info. Thanks.

Bob Salomon
25-Jan-1999, 06:24
5x is impractical if you have a camera that can not have enough extension to reach 5x.

There are a couple of ways to reach 5x.

1 is with a lens design like the Apo Macro Sironar (the reason they made one as short as 120 is that too few current cameras have enough bellows)

2 is with an enlarging or duplicating lens. Frequently used for this purpose are the Apo Rodagon N and the Apo Rodago D. Linhof makes a "Macro Shutter system" that takes lenses like this directly in to the shutter. The drawback to this system is lack of movements and very close positioning of the front of the lens to the subject. For that reason the Linhof shutter is on a long tapered tube to facilitate the leighting of small objects without the camera standard interfering with the lights.

3: reverse mounting the lenses in 2 above.

The advantage with # 2 and # 3 is that you need very little bellows for very large magnifications. A MAster Technika 45, using this system can get magnifications up t

Ellis Vener
25-Jan-1999, 15:33
Bob is correct and in agreement with Rodenstock, because his company imports Rod enstock into the US. What he did not address in either of his posts was cameras. My recommendation, and I don't work for any dealer, distributor or maker, is th e Arca Swiss F-line. This is the top of the line Arca "F" camera. If you don't l ike Arca, then the Horseman LXC. either way you want a heavy stable camera that expands and allows you the use of long bellows. A third choice if you don't mind not having rear rise & fall movements, is the Canham DLC.

Bob Salomon
25-Jan-1999, 19:44
Since he had indicated the cameras he had decided on I didn't add ours.

Obviously if he wants an extremely versatile system which has rails that telescope and endless bellows capability I would have recommended the Linhof GT or GTL AMS cameras.

We once sold to Dixie Cup a GTL 810 with a 480 lens and enough bellows and rail to use the 480 at 1:1 on 810. This would be far more extension than the poster would probably need but it was easily accomplished with a telescoping rail a couple of meters long and an 810 bellows. A 57 bellows and a 45 bellows. + a 57 intermediate standard and a 45 intermediate standard.

There are lots of cameras that can do what he is looking for. If he wants information on systems beyond what he is looking for we would be pleased if he considered Linhof.

But he seemed to be asking a question about macro lenses, specifically our macro lenses, for which he was given incorrect information. We only tried to give him accurate and complete information on the lenses and thank you for the opportunity to point out that there are more than just Arca and Horseman with the capability he i