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Over thirty years ago I remember reading an article in a photography magazine which demonstrated a technique for getting extreme depth of field in a macro shot. The results which made such an impression on my teenage self that I'm recalling them now, were blades of grass in the foreground with an entire backyard in focus maybe 50 meters of depth of field. The setup was extremely homebrew, from what I remember combining large lenses threaded back to front, and the exposure was done over as many hours of daylight as were available.

The results looked like something from Honey I Shrunk the Kids which was a popular movie around that time. It didn't look like traditional macro photography. It looked like small things were giant things. In the same way tilt shifting makes giant things look small. To this date, I've never seen photos like these, and I'm wondering if anyone knows of a technique to create similar photos. Looking back at it, it seems like black magic given the lengths one must go through using stacking to achieve even a few millimeters of depth of field in extreme macro photography.

Chris Lukic
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  • Could it have been some type of composite technique, like an analog precursor to focus stacking? Or maybe something using tilt-shift lenses? – xiota Mar 29 '21 at 21:41
  • I have a vague memory that it was a setup involving attaching lenses back to front and exposing only a small portion of the film and then blowing it up. It feel like it's a technique lost to time, but the result was so striking. – Chris Lukic Mar 31 '21 at 17:15
  • The best way that I can think of to increase the apparent depth of field without stopping down the aperture is by using a tilt-shift macro lens. Perhaps the method involved free-lensing a reversed lens. Using a smaller portion of the film may also increase apparent DOF, but at macro distances, it's not that helpful. There is list of macro techniques at What macro techniques offer an alternative to expensive optics? – xiota Mar 31 '21 at 23:37

3 Answers3

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Sounds like large format tilt to me...

Using tilt only creates the "toy world effect" because the technique creates a thin sliver of focus w/in the FOV, which appears as a very shallow depth of field; which creates the impression that the scene must have been very close and therefore very small.

It's a mental/optical illusion; and when tilt is applied to close-up photography in the more traditional manner it can have the opposite effect (unusually large DoF).

The only other method of achieving extreme DoF is using the hyperfocal distance with a short focal length lens; but that couldn't include macro level magnification.

Steven Kersting
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  • I may have not explained it very well. The effect was the exact opposite. It was an extreme depth of field at a very small scale, with both the blades of grass in the foreground in focus just as sharp as fence posts in the distance. A kind of macro Ansel Adams shot. – Chris Lukic Mar 31 '21 at 17:13
  • @ChrisLukic, with a tilt lens if you tilt it the opposite direction of the surface the apparent DoF decreases and you get the toy effect (e.g. tilt lens up when ground is moving down/away). But if you tilt it in the same direction the apparent DoF increases exponentially along that plane. See the example images here: https://www.cambridgeincolour.com/tutorials/tilt-shift-lenses2.htm – Steven Kersting Mar 31 '21 at 20:06
  • There's a few ways of accomplishing it for macro... using a bellows with tilt capability, using a macro lens on a tilt adaptor, or medium/large format with integrated tilt. The only other method of achieving extreme DoF is using hyperfocus with a short focal length lens... I used that technique for this image which seems kind of similar to your description (but not macro). https://flic.kr/p/5wdxp1 – Steven Kersting Mar 31 '21 at 20:13
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Assuming you don't help the focusing plane with a tilt lens (which is a major tool when your objects don't have too much height above the plane), the essential thing is to have an entrance pupil that is small against the subject size. That will cause diffraction that tends to be the lesser evil in macro photography than a limited depth of field. For that you want to use the smallest aperture available with your lens. Note that tele extenders placed between lens mount and (macro) lens will not just increase magnification but also increase aperture number. They allow you to go further in the tradeoff between depth of field and diffraction than the lens designers thought reasonable. With a pinhole aperture and a comparatively large focal length, you'll need a whole lot of light (and/or long exposure times).

Also these days you have a chance of reducing diffraction effects using something called "deconvolution sharpening" since the diffraction effects are essentially independent from the distance of the objects in the scene. Effective deconvolution amplifies noise significantly, so you want to work with the lowest ISO values your sensor supports, again meaning lots and lots of light.

For high-depth-of-focus photography, you can deal with some problems at the expense of others by simply omitting the lens completely and only working with a pinhole aperture and very high exposure times. Not having aperture blades at all will avoid "sunstars" (albeit the geometry of macro lense apertures should already try to minimise them, but a variable aperture is harder to perfect in that regard).

user98068
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If aperture and the projected size of the subject on the image plane are held constant, a longer focal length will provide more depth of field than shorter focal lengths. For example at f16 and 1:1 macro, a 200mm lens will provide greater depth of field than a 50mm lens.

For deeper depth of field in a macro image, use a longer focal length lens.

For conventional lenses, longer focal length lens will require proportionally greater extension (via tubes or bellows) than a shorter lens.

This may explain what you saw...a long focal length lens to increase depth of field with an extension tube making it even longer...for example a 500mm lens with an extension tube to achieve macro projection on the image plane would be approximately a meter in length.

That's why those old 8x10 view cameras often had such extreme bellows extension capability.

Bob Macaroni McStevens
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