Photo Merge combines several frames into one better one — an exposure bracket into a single high-dynamic-range photo, or a focus bracket into one image sharp from front to back. The result is a new file, catalogued and stacked with its source frames.
When a scene's range is too wide for one exposure — a bright sky over a dark interior — shoot a bracket (say −2, 0, +2 EV) and merge it. Lumidex Studio blends the well-exposed parts of each frame into one image that holds detail in both the highlights and the shadows.
The blend is halo-free — it fuses per region of the image rather than averaging the frames flat, so you don't get the tell-tale bright rim around high-contrast edges.
In macro and close-up work, depth of field can be paper-thin. Shoot the same frame several times with the focus stepped through the subject, and focus stacking keeps the sharpest version of every region to build one image that's in focus throughout.
Both merges offer the same output choices:
Auto-align corrects a straight side-to-side or up-down shift between frames — the kind handholding introduces. It does not correct rotation or a change of scale (for example the slight "breathing" of the frame as focus shifts, which is most pronounced at the edges of a wide or fisheye lens). Frames with that kind of movement can show faint ghosting.
For the cleanest result: shoot on a tripod, and make sure all the frames are the same pixel dimensions (merge needs matching sizes).
Panorama and HDR Panorama merges appear in the Photo Merge menu but aren't functional yet.