Which MF system for me?

[Nebster]

You mention that you only shoot in natural light, and that it is not always in abundant supply.

That's true, but I am generally free to shoot longer exposures, so I'm at the base ISO probly 90% of the time.

The other times, I'm either shooting a stack and want to speed things up (if it's cold, I'm pretty wimpy), or I'm shooting something that's fluttering or flickering or having cars or people drive between me and it.

It would be nice to be able to go up-ISO, and I think my expectation would be to move to a lower noise sensor down the road if not starting with the Sony one today. Perhaps I could put up with dealing with those 10% outliers in the near term.

On the lenses, you will be best off shooting at between f/8 and f/11. That's what they're optimized for.

That's interesting, I wasn't aware that they were optimized for a particular aperture. Did they pick that aperture because it's a nice balance between DOF and staying out of diffraction-limited transfer?

I know on my 4.9um pitched d800 sensor, with the very best lenses, on high-frequency subjects like I often have, I can definitely see the diffraction falloff at f/8 versus f/5.6 and between f/5.6 and f/4. With a sufficiently flat subject (rare) or a grudging switch to focus stacking (sometimes, for a good enough subject), I try to stay at f/4 or f/5.6 on my current system to get maximum sharpness. Many times I don't have that luxury and fall back to f/8, though.

 

[Nebster]

Shifting will deliver exactly what you need here - you set your camera level, focus on the wall, and then just shift the sensor around the large image circle that the lens projects.

Okay, that sounds great, but I guess the lens has to have a much wider FOV to pull that off, right?

What about if my subject is largely above my lens height? Even wider FOV?

Sometimes, my subject is below my lens and small. I have trouble getting the camera all the way to the ground, but some of the coolest stuff can be, say, on the wall 2 inches off the ground. Physically in those cases I'm often pointing down a bit. Also, I think I mentioned above that I sometimes shoot stuff on the ground from above.

I'll admit, I'm struggling tonight to figure out how I can tell how much I can shift and capture for a given focal length and image circle, even leaving out the additional complexity that I know will come into play with optical performance and ray angle issues nearer the edges, which I'm sure varies by lens and sensor*respectively.

It seems like something I'll have to just physically play with at some point to really get it. That's okay, too.

 

[jlm]

to give you a rough idea (using 24mm canon tilt/shift lens on 35mm)
shooting an architectural interior (a staircase, 12' ceilings, but stair passes up through floor opening another 4')
24mm is just wide enough i can see everything in the frame when I'm backed up to the wall behind me. tripod is at about 5 and camera is level so the verticals are plumb . by shifting, i can set the floor at the base of the stair and the 4' railing entirely in the frame. without shifting, i'm going to see way too much floor and maybe see up to 10'

 

[MGrayson]

Okay, that sounds great, but I guess the lens has to have a much wider FOV to pull that off, right?

What about if my subject is largely above my lens height? Even wider FOV?

Well, FoV is usually with respect to the sensor size. If you mean the angle of coverage, yes, that is much larger for a tilt/shift lens than for a "standard" lens. The image circle of a stationary lens is usually barely larger than required to cover the sensor. This is easier on the lens designer, makes the optics (potentially) smaller and limits internal reflections. A lens meant for shifting - either in 35mm format or larger - has a (sometimes much) larger image circle so that moving the sensor won't vignette the image.

A technical camera or a tilt/shift lens on 35mm format will do exactly what you want.

--Matt

 

[jerome_m]

Typical subject size varies from near-macro (typically 1:3 to 1:10 repro) to 8 feet square.

If you shoot objects that small, a tech cam will not be usable in the way people describe here: the necessary shifts to keep the wall and film plane parallel will be much larger than what a tech cam can do. Moreover, tech cams are not really adapted to macro: you'll need either live view, a tethered computer or removing the back and replacing it with a ground glass to frame and focus.

If I could fabricate a lens as good as the Zeiss 135/2 at any focal length, I'd probably pick 85mm as the best hybrid. More often than not, though, I walk with the 100mm for the additional close focus flexibility it offers

Because you shoot flat subjects, a change in focal length will not change your perspective. This discussion should not be limited to a particular focal length.

(and the lower chiropractic bills incurred after the trip).

Weight will be a problem with MF cameras, especially with the Fuji GX680 which was discussed earlier. I think people ignored that requirement of yours in their advice.

That's interesting, I wasn't aware that they were optimized for a particular aperture. Did they pick that aperture because it's a nice balance between DOF and staying out of diffraction-limited transfer?

Not really. The optical engineer cannot optimise at wider apertures or your lens would weight a ton and be much more expensive.

I know on my 4.9um pitched d800 sensor, with the very best lenses, on high-frequency subjects like I often have, I can definitely see the diffraction falloff at f/8 versus f/5.6 and between f/5.6 and f/4. With a sufficiently flat subject (rare) or a grudging switch to focus stacking (sometimes, for a good enough subject), I try to stay at f/4 or f/5.6 on my current system to get maximum sharpness. Many times I don't have that luxury and fall back to f/8, though.

On the D800, you should start to see the effects of diffraction between f/5.6 and f/8. You see them earlier, but only for macro photography. The reason is that, when you are focussed very close, the real aperture of your lens is smaller than what your camera tells you (it is an unavoidable property of macro lenses).

*******

Something else: you are saying that you have problems with your tripod and subjects close to the ground. Have you tried a tripod with an adjustable column, like the Gitzo explorer? I have one and it can be adjusted to bring the camera very low:

 

[Geoff]

With regard to shifting amounts - here's another way to look at it:

If you are looking for really radical amounts of shift to address "looking up at an angle" for your shots, its not likely that MFDB (or any shifting lens on a digital camera) will achieve what you want. What is meant by radical? Say a 45º look up, for example. Perhaps older film lenses on say 4x5 could accommodate this, but digital isn't quite that flexible.

Where shifting really works well is when there is a moderate amount of looking up, and you want to hold the planes parallel and reduce (or eliminate) keystoning. Figure (for the sake of discussion) say 30º or less for the angle of "looking off axis" you wanted to address.

These are just seat-of-the-pants approximations, but might give you a ways to think about this all. Some folks try eliminating keystoning by PP, but lets leave that off the table for now. Its ok for minor corrections, but not major ones.

Shifting is a slower means of working, precise, and provides very special results. Some of us like it quite a bit. The quality in working this way is remarkable. The lenses have a special look. That said, it can be a slower technique, and it takes some time to learn. It also takes time to get a combination of the various pieces (lens, camera, back) and your own working methodology in synch. It is very difficult to get that combination without working physically with all the parts. And you may find your own work flow evolving over time. That is part of the fun of working this way.

One last thing - with the combination of a high res back, with wider lenses (more than you might have considered), and shifting, you may find all sorts of possibilities opening up. Just food for thought. For example, I like to shoot wide with a 35mm lens. But a 55 with shifting and stitching does quite nicely too.

 

[gerald.d]

If you shoot objects that small, a tech cam will not be usable in the way people describe here: the necessary shifts to keep the wall and film plane parallel will be much larger than what a tech cam can do. Moreover, tech cams are not really adapted to macro: you'll need either live view, a tethered computer or removing the back and replacing it with a ground glass to frame and focus.

I could be wrong here, but I'm pretty sure he's not talking about those ratios on the sensor, but rather on the print.

Kind regards,


Gerald.

 

[Nebster]

If you shoot objects that small, a tech cam will not be usable in the way people describe here: the necessary shifts to keep the wall and film plane parallel will be much larger than what a tech cam can do. Moreover, tech cams are not really adapted to macro: you'll need either live view, a tethered computer or removing the back and replacing it with a ground glass to frame and focus.

I would say the tiny stuff is less common, but a lot of the detail is, er, in the fine details, for sure. Sometimes I find big walls or surfaces that are interesting, like this one that's probably five feet across:

But just as often the thing is pretty small, like this one that's maybe eight inches:

I definitely want to be able to shoot both subjects with the same kit.

Because you shoot flat subjects, a change in focal length will not change your perspective. This discussion should not be limited to a particular focal length.

That sounds true in theory, but the practical reality is that a change in focal length changes my distance to subject, and I don't always have the luxury of being arbitrarily far away. The lion's share of the time, though, I either have enough room or I need to be pretty close such that it's irrelevant. I suppose I mostly agree.

Weight will be a problem with MF cameras, especially with the Fuji GX680 which was discussed earlier. I think people ignored that requirement of yours in their advice.

Hm, yeah, looks like that GX680 is 12ish pounds with a full setup, wowzers.

On the D800, you should start to see the effects of diffraction between f/5.6 and f/8. You see them earlier, but only for macro photography. The reason is that, when you are focussed very close, the real aperture of your lens is smaller than what your camera tells you (it is an unavoidable property of macro lenses).

Oh, never knew that. How... unintuitive, ha.

Something else: you are saying that you have problems with your tripod and subjects close to the ground. Have you tried a tripod with an adjustable column, like the Gitzo explorer?

I can get the camera plate about 3 inches off the ground with my tripod. A long time ago I had one of those tripods with an extension arm like that, and I never could get to like it. The lever arm was such that I was always fighting vibration, and that was back in the days of 6 or 8MP. That's also one of the reasons I love the Cube and a big tripod; it's just so stable that it takes that part of the hassle out of the equation. There are so many other things nipping at my heels trying to keep me from coming away with a really high quality capture that I love the way the mega tripod just nukes that issue.

With really low positioning, I've found that I just end up putting a bean bag on the ground typically. By the way, that's one reason I love the articulating display on the 645z (and, presumably, wifi live view on a couple of the other backs). Sometimes it really stinks having to lie down on the ground to fiddle with that stuff.

Thanks for all the thoughts.

 

[Nebster]

Where shifting really works well is when there is a moderate amount of looking up, and you want to hold the planes parallel and reduce (or eliminate) keystoning. Figure (for the sake of discussion) say 30º or less for the angle of "looking off axis" you wanted to address.

I think I'm with you now. So the ideal thing would be to shift way up, into the upper region of a lens with a bigger angle of view, sort of like the equivalent of shooting with a wider lens and then just cropping to the top part of the image. This gives the benefit of parallel projection (and, if the lens is really good, presumably doesn't introduce many other forms of distortion using the outer edge of the circle that way?).

What I was thinking of was pointing up and then tilting to align the plane of focus with the vertical surface. I believe I could that, but it would "harder" perhaps (more sensitive, and possibly not solvable in just one axis unless I am perfectly aligned in the other), and I would still have keystoning.

Thanks for the food for thought. It definitely makes me want to hold one of these and play with it. I feel like it wouldn't take too long to figure out what would work (or not) -- maybe a couple hours outside with some time for reviewing on the computer in the middle.

 

[Nebster]

I could be wrong here, but I'm pretty sure he's not talking about those ratios on the sensor, but rather on the print.

I could have picked better terminology, but I was trying to express macro ratios at the sensor, yes. So some small stuff, like 6 or 8 inches across, up to pretty big subjects. Plenty of small stuff. If it helps, the Zeiss 135mm can do about 1:4, which is about as much as I ever do. I wouldn't lose sleep over something more like 1:5 or 1:6 (on 35mm) as well; the really tiny stuff is less common and usually presents too much of a hassle when I find it anyway... the DOF is just too small and painful.

 

[jlm]

most tech cameras only tilt the lens, and then shift the sensor. basic rule of thumb is you want the sensor plane to be vertical to avoid keystoning and not shift the lens (because that would change the parallax of objects in the image) tilting the lens is then done to optimize the plane of focus. usually the camera body is fixed tot he tripod as well, so shifts do not move the lens.

a full bore view camera can shift and tilt both lens and sensor, but if you tilt the sensor to correct the focal plane (which works), you will also change the sense of perspective in the image

 

[jerome_m]

If I understood correctly:
-you shoot generally flat subjects
-these can be between postcard size and car size
-they can be high up or very low, making it difficult to shoot straight on
-you want to print to huge sizes
-you want everything to be portable on a 2 hours walk.

I am not sure a medium format is the best choice: the cameras are generally heavy and the bigger sensor means that depth of field will be even more limited to what you are used to. Also: you won’t win that much resolution over your D800.

I am also not convinced that a tech cam is a solution. The shift capabilities won’t allow you to straighten the perspective on the kind of subjects you take, especially with the focal length discussed here. You will need a cmos back to have live view (so as to actually frame macro subjects and focus) and these are limited to 50 mpix (not that much better than your D800). On the positive side, you will be able to take a surface at an angle and move the plane of focus to the same angle (read on Scheimpflug).

Maybe I should describe how I would operate my MF camera on this kind of subject. Not that I am suggesting my camera is the best choice, but to explain what details make a lot of difference.

I use an Hasselblad H4D-50. I has a CCD sensor, so no live view. But the built-in AF system is very accurate, so taking a wall straight on simply means press on the focus button and shoot. All the available lenses for it will give a perfectly sharp image of a car-sized piece of wall at f/8. The resolution is such that I can print 30”x40” and have everything pin-sharp.
On the positive side for your requirements, I can also use a fairly light tripod. The camera uses a central shutter and these produce very little vibration once the mirror is up. I have a very sturdy and heavy tripod and I rarely need it.
If I wanted to take pictures near the ground, I could take the viewfinder off and replace it by a chimney finder. Then, I lose the capacity to meter light (not a big deal on static subjects). The chimney finder is quite light but bulky, so I almost never take it with me on walks.

There is a 120mm f/4 macro lens for that camera. It has about the size and weight of the 70-200 f/2.8 zoom for your Nikon. It gives about the angle of view of a 80mm on your Nikon.

The camera works best at iso 50, and you would use f/5.6-f/8, so you would have the related shutter speed. Only static subjects would do.

There is an adapter called HTS to tilt and shift on Hasselblad cameras. It can be used to shift and keep straight lines straight for architecture (sample) and shows the same limitations as technical cameras in that case: one needs short focal lengths to be able to shift enough. It is also used for product photography, e.g. watches and food, to tilt and move the plane of focus to the angled plane of the subject. For example, someone explained he used it to image pizzas at an angle and keep them sharp front to rear (you don’t do pizzas, but what you do is of similar sizes). I tried it, it works well, but adjusting focus precisely is difficult (sample). People shooting watches or food in studio shoot tethered and check on a large computer screen. Outside, looking at a screen in sunlight is difficult. Still: focussing with the HTS is much easier than on a tech cam, because you can actually look at the same image on a ground glass and then just press a button to take the picture. The ground glass is also larger and more comfortable to use than on your Nikon.

So, basically, with the camera I have, I could probably fit most of your requirements. I would use the 120 macro or the HTS and 50mm (second version, possibly with a macro adapter which exists for it). Still: I am not convinced it would be worth the price and effort (for that particular use you have). It would be marginally better than your D800, heavier and bulkier and not easier to use. Other MF cameras would not be better, as far as I know.

 

[tsjanik]

................................ By the way, that's one reason I love the articulating display on the 645z (and, presumably, wifi live view on a couple of the other backs). Sometimes it really stinks having to lie down on the ground to fiddle with that stuff.

Thanks for all the thoughts.

That feature alone would have been enough to convince me. The older I get, the less inclined I become to lie on the ground for a macro shot. Now it's not a problem. In the shot below, taken today, the ground was wet, snowy and muddy. It's not a keeper, but I doubt I would have attempted it without the screen. I intended this shot for the Behind the Scenes thread and although I'm not really happy with the results, it illustrates the advantage of the articulated screen.

 

[Nebster]

So, basically, with the camera I have, I could probably fit most of your requirements. I would use the 120 macro or the HTS and 50mm (second version, possibly with a macro adapter which exists for it). Still: I am not convinced it would be worth the price and effort (for that particular use you have). It would be marginally better than your D800, heavier and bulkier and not easier to use. Other MF cameras would not be better, as far as I know.

Thanks for this insightful description of how you'd fit your system into my pattern. I follow what you're saying, and I agree: it might be not quite enough better to justify the increases (in $, kg, time). In fact, that is the fundamental concern I have, that I won't get enough return for the marginal cost.

I'm not naive: I expect it will be a diminished marginal return! I think the d800 is at a very efficient point on the curve, at least for what I do and compared to all the options of yesteryear.

I still think multishot holds promise, and I am having a hard time figuring out whether it's viable in the field with a surfacepro. The option to do MS might be a gamechanger, with fallback to regular 50mp liveview when I don't want the complexity and hassle factor. It looks awfully clunky (at a minimum), but the detail in those 6x supersampled images is so compelling... sigh.

 

[jerome_m]

Multishot would certainly be much better than your D800, since it emulates 200 mpix. Multishot needs a perfectly static subject and tripod, however.

I am not sure that multishot backs are still available from Sinar. The one from Hasselblad will require a firewire connection and I do not think firewire is available on the surface pro. You would need a macbook with the thunderbolt adapter (a macbook air would work).

On the Hasselblad platform, I would suggest the HC50-II lens: it is excellent optically, can be used on the HTS tilt-shift adapter and can be used for macro with a special adapter ring.

Another solution would be to stitch with your existing D800. It would not be much lighter than a MF: you would need an accurate pano head to stitch at short distances and these weight a lot. But it would be considerably cheaper.