Ultra wide suggestions - Tech camera

[thomas]

While I use a Cambo WRS and not an Arca the concept should be the same; meaning flat movements of the back around the lens circle. In my case I can move my back depending on my lens up to 15mm left and right as well as 10mm up and down.

My Sinar P3 converted from a P2 is a big ugly beast, but it gives, from memory, a total of 8cm rise/fall and 8cm left/right... so, you can use an image circle of 120mm with a 36 * 48 mm sensor (this needs +/- 37mm and 32mm, according to the Schneider brochure.

I think Don referred to the image circle of his particular lenses... as the actual Wide RS body provides movements of +/-40mm (+/-20mm lateral & +25mm rise / -15mm fall).
I doubt your 80mm movements are really usable with a digiback... as the edges will go too soft - at least with wide angle lenses. Of course it depends on your application... but the falloff is really not insignificant.

 

[dick]

I think Don referred to the image circle of his particular lenses... as the actual Wide RS body provides movements of +/-40mm (+/-20mm lateral & +25mm rise / -15mm fall).
I doubt your 80mm movements are really usable with a digiback... as the edges will go too soft - at least with wide angle lenses. Of course it depends on your application... but the falloff is really not insignificant.

I think the Schneider Apo-Digitar lenses are OK, and the lenses Sinar lenses are better re edge res...
When edged res is a problem pan and stitch is an option.

 

[thomas]

I think the Schneider Apo-Digitar lenses are OK

try it!

 

[Joe]

Hello,
I am a new member with lens questions - but first a little introduction: I'm a vet photog for 40 years, mostly 35mm, with a little MF, and barely any LF. I am at home with the 5DMkII and most of the Canon lenses. I am learning the Phase One system with the 40+ and a bunch of legacy manual lenses (Hassy, Ptx 67, and Mamiya).
The Rm3di is on the way, and I am looking at a lens kit for fine art architecture/ architectural elements (wide +/- stitching), portrait (single and group), landscape/ cityscape (medium & tele +/- stitching, still-life (floral/ macro +/- stitching), art repro (icons/ tapestries).
The Phase One knowledge base article #1221 outlines the linear edge artifacts some have found with the Schneider lenses less than 50mm. This seems to suggest that the Rodenstocks might do better at less than 50mm.
Given that I am getting the Rm3di with the goal of images that are as sharp as possible, and often larger than native resolution of the Phase sensor, i.e. stitched, I am interested in several topics:

1. Do you limit your lens choices to the Digitars and Digarons? Which of the "non-digital" lenses could work equally well (?super-angulons, apo-sironars)? I mentioned that I have the 40+, but that is like a camera body - they come and go, but glass is made to last ..... I think that I want lenses that will work with the 80mp (or larger) back.
2. Best "wide" without room to stitch?
3. Best "wide" with room to stitch?
4. Best macro that may also be useable at longer distances (portraits) or useable with stitching (for long tapestries or tall icons)?
5. What teles are stuck in your cold dead fingers?

So if you can't get the Cube ..... what's your vote for a stick-topper, and why? I'm guessing something with gears.

Newbie questions:
6. If you tilt, do you lose room to stitch because the image circle is smaller, (and is the shrinkage significant)?
7. Does the limited amount of shift on the R series mean that anything above a certain image circle size is actually wasted - what is the maximum useable image circle for the RL - the largest of the R series ( that I might actually use some day)?
8. Why do the Schneider apo-digitar 60N, 90N, 100N all have a 53 degree angle of view?
9. Why do the Apo digitar 47 and digitar 28 both have 92 degree angle of view? (Obviously I come from the little land of 35mm where angles of view progress logically - I just don't understand the logic here)

Blessings, and thanks for your time and opinions.

 

[thomas]

just to start somewhere...

So if you can't get the Cube ..... what's your vote for a stick-topper, and why? I'm guessing something with gears.

on a technical camera of course something with gears. Arca's new D4 head is a perfect match IMO.

Does the limited amount of shift on the R series mean that anything above a certain image circle size is actually wasted - what is the maximum useable image circle for the RL - the largest of the R series ( that I might actually use some day)?

limited amount of shift? There are "digital large format" cameras that provide larger movements, but the 30/10mm + 15/15mm of the Rm3D will do for most purposes. At larger movements you have to deal with heavy sharpness falloff anyway (at least with wide angels)
On the other hand the lateral +/-15mm shift on the Rm3D might be a reason to consider a digiback with a larger sensor plane... such like a P45 or P65 ...
"Image circle" is an attribute of the lenses, not of the camera. However the movements a certain camera provides may or may not limit the actual usable image circle of a lens.

9. Why do the Apo digitar 47 and digitar 28 both have 92 degree angle of view?

the 47 has a much larger image circle. When stitiching you are literally increasing the sensor plane... so the 47 stichted to a larger sensor plane results in the same angle of view than the 28 (simplified speaking).

 

[GrahamWelland]

So Terry, did you finally choose a super-wide for use with the P40+? Personally I've been looking at 28mm offerings, with the new Schneider being of particular interest. Did you reach any conclusions in your search?

 

[Terry]

No, not yet. I have a 35 schneider, 90mm Schneider. I also have the new 60mm on order. The 24 mm is the lens I would get but I haven't pulled the trigger yet. Even if I decided today it would take a couple of months to get that lens.

 

[dick]

Hello,

9. Why do the Apo digitar 47 and digitar 28 both have 92 degree angle of view? (Obviously I come from the little land of 35mm where angles of view progress logically - I just don't understand the logic here)

just to start somewhere...

The 47 has a much larger image circle. When stitiching you are literally increasing the sensor plane... so the 47 stichted to a larger sensor plane results in the same angle of view than the 28 (simplified speaking).

The 90 also has a 92 degree "lens field of view".

Technical camera lenses have image circles bigger than the the minimum required to cover the format/sensor/GG, to permit camera movements for perspective correction, stitching, etc.

The concept here is the difference between the
lens field of view, which projects a circular
image circle.

And the Format field of view, which is what you get in the picture ...the part of the image circle that falls on the sensor/GG/film.

The image circle is a slice of the projected cone, so, at higher magnifications (greater extensions) the image circle is bigger.

...so shift-and-stitching 4 or 6 60 Mpx images with the 47 can give the same Stitched-format angle of view as the 28.

Lenses wider that 47 are a PITA to use and usually need a special "pancake" camera or give you no movements, and, with a 47 you can get wide enough for most purposes by stitching.

 

[Joe]

Thankyou Dick,
That helps.
Joe