A reader takes the number of images from the innermost axis of the sample chain when no axis varies,
and chi/phi are innermost whenever they are present. Written as scalars, a still or a grid scan with
a recorded head position imported as ONE image however many were collected - dxtbx falls back to
nxsample.depends_on and takes num_images = len(scan_axis).
NXmx has no attribute that would say otherwise: there is no "equipment", and equipment_component
identifies a rigid assembly ("detector_arm", "detector_module"), which dxtbx reads only for the
detector module hierarchy. The axis length is what carries the image count.
Both writer paths are fixed, and the goniometer in BuildTransformationChain now takes its container
whenever the image count is known, as the writer already did - a stationary spindle sent over CBOR
had the same one-image shape.
Verified against DIALS 3.27: same file, chi/phi as scalars imports as 1 image, as per-image arrays
as 5.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VfYvJT5Nb71suJCowRBn5z
leonarski_fandClaude Opus 5
8dd3ee6576
