Use flats/darks from another dataset
1. Use "true" darks/flats from another dataset
In some cases, multiple scans are queued one after another, and only the first/last have darks/flats. In these cases, it should be good to have a simple way to "just use flats/darks from another dataset".
The current way involve either:
- Use a tomwer widget
- Use
darks_flats_dir
and rename flats/darks to the current dataset prefix (this entails to have them already reduced) - Use
nxtomomill patch-nx --flats-at-start
(for example). But there are some failure cases.
Proposed: add use_flats_from_dataset = <link to nx file>
in [preproc]
This would
- Do the frames reduction
- Insert flats at the "right location" (i.e possibly edit the index)
2. Use another dataset "as" a series of flats/darks
Sometimes a sample is contained within a non-trivial medium. A full tomography of the "top" of the container is done, then this scan is used as a reference to normalize the other scans. This first scan is hereby denoted as "reference scan".
This reference scan contains only projections (?). These projections are used as flats by other datasets.
The flats reduction should be done by angular range, with a granularity defined by user. For example:
-
flat_0 = median(flat(-10), ..., flat(10))
: the reduced flat for angletheta=0
degree is obtained by reducing the projections from angle -10 degrees to 10 degrees flat_90 = median(flat(80), ..., flat(100))