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Two changes to the desktop editor, both about photographs with something far away in them.
The lens can be changed after you have seen the scene
The lens a photograph was taken with decides the shape of the reconstruction, not merely its scale, and a photograph that does not record its own is unprojected through a 30 mm default that is usually wrong. The editor asked for the number before uploading — which is advice nobody can follow, because the whole difficulty is that it cannot be judged until the scene exists and you have looked at it.
Rebuild at this lens, under the same field, builds the photograph the server is already holding again through a new number. Nothing is uploaded a second time: the picture is still in the job directory, and the scene keeps its place, so this can be tried as often as it takes to find the right one.
The backend could always do this and the phone could always ask for it — but only for a photograph that recorded no lens of its own. The desktop, which is the one place with a screen large enough to judge the shape on, could set the number once and never revise it. It is now offered for any held scene, including one whose EXIF recorded a lens, because a photograph can record one and record it wrongly. A 360 is six reconstructions merged and cannot be rebuilt this way.
It is a separate button from Generate deliberately. Generate needs a file, clears the stored scene and starts a different one; this takes no file and replaces the scene where it stands.
Turning a scene with a distant background is controllable
Dragging to turn a photograph with a background — a landscape, a room with a window, anything with sky — threw the subject across the frame faster than a mouse could be aimed.
The camera orbits a point at the median distance of the gaussians. That is right when the subject fills the frame, and wrong when it does not, because the median lands in whichever half is larger: in a landscape, the background. In one measured scene the nearest splat sat at 1.20 units and the median at 57.83, so the camera swung on a radius forty-eight times the distance to the subject, and a ten pixel drag moved it three times further than the subject was away.
Finding the subject instead was tried and abandoned against that same scene. It is not two clusters with a gap between them but four humps with no gap at all: the largest step between neighbouring sampled distances across its middle nine tenths is two and a half per cent, which is noise, and a valley in log space exists but there are two of them, five times apart.
So the pivot is bounded rather than guessed. What makes a distant pivot unusable is not how far away it is but how that compares to the nearest thing on screen, because that ratio is exactly how much a drag is magnified there. A scene whose subject fills the frame is left alone; so is a landscape with nothing near it, where everything is far and the ratio is small.
In stereo this counted twice, since pivot mode puts the plane of the screen at the same distance and had been putting it on the horizon.
Nothing on the phone changes.
The full description of what this project is, and the two external conditions worth reading before installing, are in v1.0.