Question about metering

How does the metering process work?

I have two different metering values for the same frame but mounted differently.
One is mounted on a glass mount that does not cover any part of the film, (full frame)
The other is with a slide mount.

Resulting scans show the same exposure.

**So, my question is:**
Is the film scanned with the exposure set during the metering process and then adjusted in software?
Or
Is the film scanned with the exposure already adjusted to compensate for the slide mount (too dark) or a cut frame (too bright)?

Metering Full Frame
[full-frame.tiff](https://github.com/user-attachments/files/31117766/full-frame.tiff)
```
2026-08-16T13:44:03.539917Z INFO focused at position=119
2026-08-16T13:44:03.540380Z INFO Focused frame=1 focused=Yes
2026-08-16T13:44:16.356377Z INFO Metered frame=1 exposures=Exposures({Red: 107964, Green: 83890, Blue: 75373})
2026-08-16T13:44:27.573250Z INFO 722 x 493 at 500 dpi, wrote scan_1.tiff frame=1
```

Metering with Slide Mount
[slide-mount.tiff](https://github.com/user-attachments/files/31117767/slide-mount.tiff)
```
2026-08-16T13:45:23.086357Z INFO focused at position=215
2026-08-16T13:45:23.086837Z INFO Focused frame=1 focused=Yes
2026-08-16T13:45:35.916547Z INFO Metered frame=1 exposures=Exposures({Red: 84482, Green: 65690, Blue: 59014})
2026-08-16T13:45:46.124767Z INFO 722 x 493 at 500 dpi, wrote scan_2.tiff frame=1
```