Sarcococca confusa meets and defeats Scheimpflug principle

[elf]

Scheimpflug principle can only get 3 points to lie on a plane, but the Sarcococca has at least 5 that need to be in focus

This is the first (semi-successful) image I've taken after adding tilt and swing movements to my macro panorama head.



The flower is 10mm wide. The movement settings were 15 degrees tilt up, 15 degrees left swing, 5mm right shift, 0mm fall.

Lens 50mm El-Nikkor at f/11. Magnification is approx 1:1.3.

I should have read http://www.bobwheeler.com/photo/ViewCam.pdf and http://en.wikipedia.org/wiki/Scheimpflug_principle more thoroughly before designing the tilt/swing mechanism and noted that close-ups require a lot more movement. The tilts are limited to about 30 degrees which is not enough to bring a horizontal plane into focus with the subject at 67mm and 100mm bellows draft and the axis of the lens at 45 degrees. According to my rough calculations, this would need about 60 degrees of tilt. If you move out of the macro range then much less tilt is required. Typically only a few degrees tilt are needed to bring the proverbial flower and mountain into focus.

The really nice thing about movements is that it now takes hours to compose a single shot instead of just pointing and shooting

[Charles Krebs]

Elf,

Yes, tough to use for extreme closeups. An even bigger problem than the degree of mechanical movement needed in the camera, is finding a lens that will allow that much movement and still provide some semblance of image quality.

[elf]

How true. I was outbid by a total of $4.00 on two Mamiya 80mm lenses this last weekend. If only I could afford this one: 160314136630

[elf]

Somehow I missed this one earlier.

[kds315*]

I had very good results using a Symmar 120mm which has quite a large image circle or a Componon-S 100mm (both with suitable t/s bellows of course)

[elf]

I need a lens that has the following characteristics (listed in order of importance)
1. Cheap.
2. Flange focal distance > 63mm. Mamiya 645 at 63.3mm is at the minimum flange focal distance for movements at infinity focus. Pentacon Six and Hassleblad at over 74mm would be even better.
3. Fast. Diffraction is a big problem, so f/5.6 lens are too slow for the 4/3rds cameras. 2.8 in a medium format lens is probably the most reasonable for fast and cheap.
4. Sharp. Zeiss makes a ton of different medium format lens, but how does one determine if the lens is sharp enough on a DSLR?

Unfortunately #1 probably elimates 2 -> 4 :

[kds315*]

EL-Nikkor 135mm + 105mm are rel. cheap to find. Unfortunately they are not very bright, but they are very sharp and have large image circles. Zeiss S-Planar 74mm is tack sharp and has a large image circle too, optimized for 1:1 and compared to an UV Sonnar really cheap. Sorry, "cheap" is a very relative term...

[Harold Gough]

Klaus,

It's good to see you here. I discovered your excellent macro lens website a few months ago.

Harold

[Charles Krebs]

Elf,

Mamiya 645 at 63.3mm is at the minimum flange focal distance for movements at infinity focus.

Now I'm a little confused... are you looking for "infinity" focus, close-ups, or both? Focal length?

Pentax 67 has a flange to film distance of just under 85mm. They made some truly excellent lenses. The 90/2.8 is great and should be very modestly priced on the used market. I would not hesitate to use mine on 35mm, although the 4/3 sensor is only half that size. (And I've never extended it too far into the "close-up" range).

As you alluded to earlier... the higher the magnification the more movement you need. I'm not sure even medium format lenses will provide enough coverage for the degree of tilt you seem to want for closeups. One problem is that nearly all of your "Scheimpflug" benefits need to be accomplished with the lens standard... so you need a very large coverage. With SLR camera bodies, the "tunnel" or "throat" from the lens mount to the film/sensor limits how much tilt/swing can be accomplished with the back before serious mechanical vignetting occurs. With a view camera it is possible to tilt/swing the back significantly more, so you can work with optics with less coverage. (Although depending on the subject and camera position this can sometimes result in too much subject distortion).

Klaus' advice about enlarging lenses for larger format is good. 135mm enlarging lenses were made that covered 4x5" (150mm was more "normal" for 4x5). These are likely your best bet to get the coverage you need for the tilts needed for modest close-up work. But forget about a maximum f2.8 aperture, more like f5.6. I've used a (designed for medium format) 80/4 Componon-S with the "swing" on the Nikon PB-4 (with APC sized sensor) and frankly it's really only useful at fairly low magnifications.

[lauriek]

I'm not sure I completely understand Charlie's last post, but if I understand the second to last paragraph correctly, then it occurs to me that Elf may be interested in the upcoming Oly micro4/3 cameras, as these have a much thinner body and less 'flange-film' distance.

The cameras will have no optical viewfinder, EVF/Liveview only as they are not proper DSLRs, DSLs I guess, no Reflex!) I understand they should be able to use 4/3 lenses, so might be adaptable to his kit... (The Panasonic G1 is out already but personally I'd hang on for the Oly!)

I think there was a thread about the Pany G1 somewhere on the forum in the last month or two....

[elf]

EL-Nikkor 135mm + 105mm are rel. cheap to find. Unfortunately they are not very bright, but they are very sharp and have large image circles. Zeiss S-Planar 74mm is tack sharp and has a large image circle too, optimized for 1:1 and compared to an UV Sonnar really cheap. Sorry, "cheap" is a very relative term...

I'll look for these. And yes cheap is very relative, but getting less and less as the world economy deteriorates

Now I'm a little confused... are you looking for "infinity" focus, close-ups, or both? Focal length?

Both infinity and close-ups, which narrows the range of lens available. At infinity I wouldn't expect to use more than 10 degrees of tilt or swing.

Pentax 67 has a flange to film distance of just under 85mm. They made some truly excellent lenses. The 90/2.8 is great and should be very modestly priced on the used market.

It looks like the current market price is around $500 for these, so definitely a possibility

I'm not sure even medium format lenses will provide enough coverage for the degree of tilt you seem to want for closeups. One problem is that nearly all of your "Scheimpflug" benefits need to be accomplished with the lens standard... so you need a very large coverage. With SLR camera bodies, the "tunnel" or "throat" from the lens mount to the film/sensor limits how much tilt/swing can be accomplished with the back before serious mechanical vignetting occurs. With a view camera it is possible to tilt/swing the back significantly more, so you can work with optics with less coverage. (Although depending on the subject and camera position this can sometimes result in too much subject distortion).

I've already seen this just using shifts. I was trying to avoid adding movements to the lens, but will probably end up with them. I wanted to keep the entrance pupil fixed to make it easier to do panoramas, but using movements and rotating around the entrance pupil may not be practical because refocusing will probably be required for each frame of the pano.

I'm not sure I completely understand Charlie's last post, but if I understand the second to last paragraph correctly, then it occurs to me that Elf may be interested in the upcoming Oly micro4/3 cameras, as these have a much thinner body and less 'flange-film' distance.

The cameras will have no optical viewfinder, EVF/Liveview only as they are not proper DSLRs, DSLs I guess, no Reflex!) I understand they should be able to use 4/3 lenses, so might be adaptable to his kit...

The micro 4/3rds have about 20mm less flange focal distance than the full 4/3rds mount and no mirror vibrations to deal with. It remains to be seen if the IQ will be good enough. It's rumored that the camera's will be targeting entry level users, so they will probably have a big AA filter and lots noise reduction. If we're really lucky, they'll make a mid-level camera with an electronic shutter.

[Charles Krebs]

Elf,

The Pentax 67 90/2.8 should be readily available used for between $100-250.

[lauriek]

Elf,

I'm sure you are right they will do an 'entry level' model designed as a step up from P&S cams (the same market I think the G1 is primarily aimed at), but there are rumours of two u4/3 bodies coming from Oly and I'm really hopeful for a mid-range model!

[Cyclops]

Somehow I missed this one earlier.

Good grief,23 grand! But then that is a 300/2.8 AND a Zeiss! Not sure how'd you'd get macros out of it tho

[lauriek]

Simply add a 1.5 metre long bellows for 5:1!