Depth of Field, Diffraction and Landscape Photography with an MFDB

[baudolino]

Having used an MFDB for about a year (Sinar eMotion 75 / Hy6) and having read the various threads here (which confirm my observations), am I right to conclude that there is almost no point in using a medium format digital back on a typical medium format system for landscape photography?

The arguments:

(a) medium format digital inherently has more limited DoF than smaller sensors
(b) digital (any chip size) has a very steep fall-off of sharpness outside of the very thin plane of focus (compared to film), this is even more visible on the ultra sharp output from MFDBs
(c) stopping the lenses down beyond f8.0 to increase DoF is not really helpful since we start losing detail and contrast through diffraction; the lenses are not optimized for use fully stopped down

Now what puzzles me is that something like a Leica S2 is often pitched as the "landscape shooter's camera" and a lot of people, myself included, have gone into MFDB to achieve higher quality in landscape photography. But for the above reason, this would seem a bit pointless.

What confuses me even more is why the manufacturers all seem to offer fast lenses that are optimized for shooting wide open or near wide open. This may be great for the fashion shooters (the biggest market) but these lenses would seem far from ideal for landscape. And even for portrait photographs, I often find that I have to stop down to f5.6-8.0 (especially with something like a 180mm lens) to achieve acceptable range of sharpness (unless I want to always be "creative" and have everything unsharp except for the person's eyes - and frankly I often want also the nose and the ears sharp or at least not completely OOF).

So what are the solutions here for the landscape shooters trying to maximize DoF while using the performance of their digibacks to the full - is it using lenses originally designed for use with LF cameras and optimized for shooting at small apertures, like the Digitars, on something like an Alpa?
Or is there some way around these constraints with the more mainstream MF SLR systems?
In the light of the above arguments, is something like a Leica S2 really a landscape photographer's "dream camera" as we sometimes read here and on the other discussion fora?

 

[Mike M]

Digital chains us to F8 because of diffraction. But it also has an impact on focus because many of the traditional view camera movements used to manipulate focal planes will cause color problems and other aberrations (depending on the digital system)

The only way to shoot digital is to think around these problems. Ultra-wide angle is a good solution for digital because F8 on a very wide lens can pull much of a landscape into focus without need for extra movements. Alpa is of course a great system for ultra-wide.

My idea of traditional landscape photography is still ruled by 8x10 fine art of the past. People that are trying to make digital hasselblads, mamiyas, and leica's into landscape cameras are sort of not following the traditional idea of what landscape photography is all about. That's OK and people can do whatever they want, but maybe they were the bad kid in kindergarten that was always trying to make a square block fit into a triangle opening.

There are a myriad of reasons as to why film is still very legitimate in landscape photography not the least of which is diffraction, or camera movements, manipulation of focal planes etc.

Another thing to consider is that perfectly sharp focus from foreground to infinity can actually destroy the illusion of depth. So while front-to-back focus might be a technical exercise in craftsmanship it might not always be what's desired in terms of aesthetics and creating the illusion of 3 dimensional depth in an image. I still think that film does this better than anything because the transitions between in-focus and out-of-focus areas are smoother than with digital. The S2 actually excels in this area since it lacks many of the protective filters and AA filters etc of the other digital cameras and backs.

Just some thoughts.

 

[baudolino]

Digital chains us to F8 because of diffraction. But it also has an impact on focus because many of the traditional view camera movements used to manipulate focal planes will cause color problems and other aberrations (depending on the digital system)

The only way to shoot digital is to think around these problems. Ultra-wide angle is a good solution for digital because F8 on a very wide lens can pull much of a landscape into focus without need for extra movements. Alpa is of course a great system for ultra-wide.

My idea of traditional landscape photography is still ruled by 8x10 fine art of the past. People that are trying to make digital hasselblads, mamiyas, and leica's into landscape cameras are sort of not following the traditional idea of what landscape photography is all about. That's OK and people can do whatever they want, but maybe they were the bad kid in kindergarten that was always trying to make a square block fit into a triangle opening.

There are a myriad of reasons as to why film is still very legitimate in landscape photography not the least of which is diffraction, or camera movements, manipulation of focal planes etc.

Another thing to consider is that perfectly sharp focus from foreground to infinity can actually destroy the illusion of depth. So while front-to-back focus might be a technical exercise in craftsmanship it might not always be what's desired in terms of aesthetics and creating the illusion of 3 dimensional depth in an image. I still think that film does this better than anything because the transitions between in-focus and out-of-focus areas are smoother than with digital. The S2 actually excels in this area since it lacks many of the protective filters and AA filters etc of the other digital cameras and backs.

Just some thoughts.

Yes, I agree with the conclusion re film. I am waiting for the 6x6 back for the Hy6 (should be launched at Photokina, keeping my fingers crossed).

 

[thomas]

First, I disagree that f8 is the smallest acceptable aperture with MFD. This… and the following… goes for DBs with a pixel pitch around 6µm.
Yes, there is some slight loss of contrast at f11 but you'd always consider it as "sharp" (razor sharp).f16 is noticeable diffraction limited… but only if you compare it directly to the same shot taken at f8. I'd consider f16 as fully usable (i.e. with an acceptable loss of "sharpness").At least this goes for my lenses.

Then again, you are right… DOF is limited.
IMO the ways to maximzie DOF are…
- tilt
- focus stacking
- shooting the same scene at f8 and f16 (or even f22) and merging these two shots to one

I agree with Mike about sharp focus from the foreground to infinity.
It is a certain (actually very special) style and not an end in itself...

 

[baudolino]

First, I disagree that f8 is the smallest acceptable aperture with MFD. This… and the following… goes for DBs with a pixel pitch around 6µm.
Yes, there is some slight loss of contrast at f11 but you'd always consider it as "sharp" (razor sharp).f16 is noticeable diffraction limited… but only if you compare it directly to the same shot taken at f8. I'd consider f16 as fully usable (i.e. with an acceptable loss of "sharpness").At least this goes for my lenses.

Then again, you are right… DOF is limited.
IMO the ways to maximzie DOF are…
- tilt
- focus stacking
- shooting the same scene at f8 and f16 (or even f22) and merging these two shots to one

I agree with Mike about sharp focus from the foreground to infinity.
It is a certain (actually very special) style and not an end in itself...

Thomas, the focus stacking (is this like focus bracketing?) and shooting at 2 different apertures and merging are something I was thinking of when I started the thread - what would be the procedure to merge the images (presumably stacking them as layers in PS and then what?).

 

[thomas]

Thomas, the focus stacking (is this like focus bracketing?) and shooting at 2 different apertures and merging are something I was thinking of when I started the thread - what would be the procedure to merge the images (presumably stacking them as layers in PS and then what?).

as to "focus stacking" - yes, you shoot some frames with the focus shifting from near to far (in small steps). Then use Helicon: http://www.heliconsoft.com/heliconfocus.html
As to the 2 shots at different apertures you actually just have copy the sharp part of the f8 shot in the shot taken at smaller aperture. As at different apertures the framing/magnification changes a little bit you have to do some retouching... or you just can crop (cut) the 2 shots in appropriate pieces and load them in Photoshops merger. Depending on the motif one way or the other works better.

 

[Bill Caulfeild-Browne]

I think there's some muddled thinking going on here. While a theoretical minimum aperture may indeed be f8, various lens aberrations and shortcomings mean that f11 or f16 are rarely distinguishable from f8 in the final PRINT.

Sure, pixel peeping at 100% on your monitor may reveal differences, but I'm not aware of any print that would show them. In fact, in practice I find the P65+ handles f16 or even f18 without discernible differences in print.

If you want to test this, take a MFDB shot to, say, 24 by 30 ins and compare it with the same size from, say, my Sony a900. The detail is clearly better with the MFDB. So is the DR. But yes, one does have to stop down at least an extra stop - or even two- to get the same dof.

Admittedly, if you're going no larger than 16 by 20, there's no reason to use MFDB - except you can crop the heck out of the file and still make a fine print!

I used to shoot 4 by 5; I find that MFDB is the closest I can get to the fine detail I got from film.

There's a good article on this on LuLa - I'll look it up and provide the link.

Bill

 

[Bill Caulfeild-Browne]

Here is the article - http://luminous-landscape.com/tutorials/resolution.shtml

Note the second paragraph below Table 3. "The only alternative way for more detail is for more capture surface" that is, a larger format.

 

[Paratom]

1) Why does landscape photography automatically mean that you have to have everything razor sharp from the forground to the horicont?
2) if you are not super close I find there is still quite a bit DOF even at f8.
3) if you allready have a Sinar back with Hy6 mount and want to achieve more DOF control I would recommend a technical camera - I really like the Artec with the sliding back. If you choose a 40HR or 70HR you have quite a bit room for movements.
4) Personally I would be to much concerned to close down f-stop to f11 if I want a little more DOF. As others said I am sure you would find some difference if you search for it, but I am sure you still get a very high IQ.

Having used an MFDB for about a year (Sinar eMotion 75 / Hy6) and having read the various threads here (which confirm my observations), am I right to conclude that there is almost no point in using a medium format digital back on a typical medium format system for landscape photography?

The arguments:

(a) medium format digital inherently has more limited DoF than smaller sensors
(b) digital (any chip size) has a very steep fall-off of sharpness outside of the very thin plane of focus (compared to film), this is even more visible on the ultra sharp output from MFDBs
(c) stopping the lenses down beyond f8.0 to increase DoF is not really helpful since we start losing detail and contrast through diffraction; the lenses are not optimized for use fully stopped down

Now what puzzles me is that something like a Leica S2 is often pitched as the "landscape shooter's camera" and a lot of people, myself included, have gone into MFDB to achieve higher quality in landscape photography. But for the above reason, this would seem a bit pointless.

What confuses me even more is why the manufacturers all seem to offer fast lenses that are optimized for shooting wide open or near wide open. This may be great for the fashion shooters (the biggest market) but these lenses would seem far from ideal for landscape. And even for portrait photographs, I often find that I have to stop down to f5.6-8.0 (especially with something like a 180mm lens) to achieve acceptable range of sharpness (unless I want to always be "creative" and have everything unsharp except for the person's eyes - and frankly I often want also the nose and the ears sharp or at least not completely OOF).

So what are the solutions here for the landscape shooters trying to maximize DoF while using the performance of their digibacks to the full - is it using lenses originally designed for use with LF cameras and optimized for shooting at small apertures, like the Digitars, on something like an Alpa?
Or is there some way around these constraints with the more mainstream MF SLR systems?
In the light of the above arguments, is something like a Leica S2 really a landscape photographer's "dream camera" as we sometimes read here and on the other discussion fora?

 

[Quentin_Bargate]

We had the same problems with film, but the solutiions with digital are not merely the same, but better.

For example, Focus stacking is far easier than with film because you should have perfect registration between several tripod mounted digital shots. That is very difficult to achieve with scanned film.

Solutions such as Hasselblad's HTS-1.5 tilt/shift adapter provide similar movements to a LF camera, or you can stick the digital back on a view camera to operate as with film.

I think the issues are largely that digital MF is less forgiving. We could get away with more with film because film grain and lack of film flatness hid the issues.

Quentin

 

[dougpeterson]

First, I disagree that f8 is the smallest acceptable aperture with MFD. This… and the following… goes for DBs with a pixel pitch around 6µm.
Yes, there is some slight loss of contrast at f11 but you'd always consider it as "sharp" (razor sharp).f16 is noticeable diffraction limited… but only if you compare it directly to the same shot taken at f8. I'd consider f16 as fully usable (i.e. with an acceptable loss of "sharpness").At least this goes for my lenses.

I think there's some muddled thinking going on here. While a theoretical minimum aperture may indeed be f8, various lens aberrations and shortcomings mean that f11 or f16 are rarely distinguishable from f8 in the final PRINT.

Sure, pixel peeping at 100% on your monitor may reveal differences, but I'm not aware of any print that would show them. In fact, in practice I find the P65+ handles f16 or even f18 without discernible differences in print.

Couldn't agree more with the above.
- DOF is less but not drastically less
- f/8 may be theoretically the best, but f/11 is nearly identical and f/16 is often still good (base on 6 micron backs with exceptional lenses)
- there are great tilt solutions that greatly increase apparent DOF in most landscape situations. Many, like the Cambo Wide RS, Artec, RM3D do so without adding any glass elements and therefore show virtually no loss in quality within the usable parts of their image circle.
- not every image benefits aesthetically from front-to-back focus
- DOF stacking, especially for 2 or 3 captures is relatively easy and can be done with excellent quality. I suggest Helicon Focus (rather than the built in functions in Photoshop)

Doug Peterson (e-mail Me)
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[dougpeterson]

Admittedly, if you're going no larger than 16 by 20, there's no reason to use MFDB - except you can crop the heck out of the file and still make a fine print!

I would say it a bit differently. If you aren't printing large there's no reason to use a high-resolution MFDB other than the ability to make significant crops.

You can still find many very good arguments for using a moderate resolution (e.g. 16/22/33 megapixel digital back: dynamic range, color, lens renderings, the physical feel/work-flow of the larger cameras, the ability to use many different bodies/platforms with the same sensor, aspect ratio (native square capture or preference for 4:3 over 3:2), waist level finder or ground glass, tethered shooting speed, beautiful low-DOF lenses (e.g. 110mm f/2 which is more than a match for a Nikon 85mm f/1.4), specialty applications (high magnification macro, pinhole cameras, IR photography, ultra-long-exposures) etc etc etc.



Doug Peterson (e-mail Me)
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[Bill Caulfeild-Browne]

I would say it a bit differently. If you aren't printing large there's no reason to use a high-resolution MFDB other than the ability to make significant crops.

You can still find many very good arguments for using a moderate resolution (e.g. 16/22/33 megapixel digital back: dynamic range, color, lens renderings, the physical feel/work-flow of the larger cameras, the ability to use many different bodies/platforms with the same sensor, aspect ratio (native square capture or preference for 4:3 over 3:2), waist level finder or ground glass, tethered shooting speed, beautiful low-DOF lenses (e.g. 110mm f/2 which is more than a match for a Nikon 85mm f/1.4), specialty applications (high magnification macro, pinhole cameras, IR photography, ultra-long-exposures) etc etc etc.



Doug Peterson (e-mail Me)
__________________
Head of Technical Services, Capture Integration
Phase One, Leaf, Cambo, Canon, Apple, Profoto, Eizo & More
National: 877.217.9870 *| *Cell: 740.707.2183
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I quite agree, Doug - and you said it better than me!
Bill

 

[thomas]

- DOF stacking, especially for 2 or 3 captures is relatively easy and can be done with excellent quality. I suggest Helicon Focus (rather than the built in functions in Photoshop)

I think it depends a bit. HeliconFocus is certainly much more sophisticated than Photoshops built in tools (actually mostly specialized third party tools provide better results than Photoshops bulit in tools... except maybe for rotation/straightening). For focus stacking of multiple captures HeliconFocus is probably the first choice.
However Photoshops "Photomerge" does a nice job in "repositioning mode" as there is no image transformation/interpolation involved. To merge two shots of the same scene shot at f8 and f16 you simply have to cut the two captures in appropriate pieces (2 or 3) and load them in "Photomerge" to let Photoshop do the stitching (i.e Photoshop just has to find the pixels).

 

[Mitchell]

The Hy6 has built in focus bracketing which means you don't have to touch the camera between shots to produce a complete focus series.

Best,

Mitchell