Parallax-Free Shift-Lens Stitching for 168 megapixel Images on Fujilm GFX 100 II, GFX100S, etc
Related: Acratech, Brian K, Eastern Sierra, entrance pupil, Fujifilm, Fujifilm GF 110mm f/5.6 TS Macro, Fujifilm GF 30mm f/5.6 TS, Fujifilm GFX100S, Fujifilm Lenses, Fujifilm medium format, Fujifilm mirrorless, image stitching, medium format, Mt Conness area, peak bagging, Really Right Stuff, shift lens, tilt shift, tripods and support
Fujifilm GFX100 II | Fujifilm GF 30mm f/5.6 TS | Fujifilm GF 110mm f/5.6 TS | Fujifilm GF 55mm f/1.7 WR.
Reader Brian K writes:
One thing I noticed about the GF 30mm shift, it has a collar that allows the lens optics to remain in place and to shift the camera body to the sides. That is the proper way to do a shift pano, like you would if using a view camera, not the body remaining fixed and the lens moving. It appears though that the new GF 110mm TS does not have that feature.
A few years back I bought a Fotodiox Hasselblad to GFX TS adapter, I had a camera machinist attach a mount to the front half of the shift collar allowing the optics to remain fixed and the camera body to be shifted. Seems like Fuji was thinking along the same lines with the 30mm, shame they did not do that for the 110mm.
DIGLLOYD: correct, I mentioned this in my earlier post.
What Brian is referring to here is that the lens collar allows keeping the entrance pupil of the lens in a constant position, which eliminates all parallax. The entrance pupil is often erroneously referred to as the “nodal point”. When the entrance pupil stays in the same position, there is no parallax.
Workaround for the 110/5.6 TS, which lacks a tripod collar
15mm offsets to be used for counter-shift
In spite of its lack of a tripod collar, the 110/5.6 TS can still be used for parallax-free shift-lens stitching.
This requires (1) a high quality clamp (larger sizes are better) engraved in millimeters, and (2) a camera plate with a marking for centering vs the clamp (even a scratch will do). To achieve a parallax free set of images:
- Take one image no shift.
- Shift the lens (eg 15mm).
- Counter-shift the camera within the clamp, in the opposite direction.
- Repeat in the other shift direction (assuming the goal is the full 168MP stitched image).
- In Photoshop, layer the images, then join the images (Auto Align then Auto Blend).
With this technique, the entrance pupil remains in the same position (or close enough) so that parallax is avoided.
A high quality clamp like the Really Right Stuff B2 Pro II or Acratech heads are ideal so long as they have engraved 1mm markings.
IMO, lever clamps suck in general (problems sooner or later) and particularly for this purpose, as they are harder to move the rig while doing the counter-shift. Screw-knob clamps are 'bulletproof' and allow these easy counter-shift adjustments. I use the Acratech Panoramic Head as shown at right, in its battle-worn state after some years. The Really Right Stuff B2-Pro-II 60mm Screw-Knob Pro Clamp is also an outstanding choice.
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