Its nice that there is the ability to go back to each sequence. But each processing step also adds a large number of files. becomes a disk space problem when there are lots of short exposure subs of high resolution.
I am already using symbolic links (Windows 10) for the FITS conversion step. Any other suggestions apart from a new or external SSD ?
So heres my understanding as of now from a practical point of view
For disk space reduction, use any combination of symbolic links, 16 bit, and compression
For compression, there are 4 algorithms in SIRL - RICE. HCompress, and GZIP 1/2
16 bit images can be compressed with any of them. But RICE and HCompress will work only with 16 bit
If using HCompress, need to set the HCompress Scale Factor. A factor of 0 or 1 will mean lossless compression. Above 1 becomes lossy. A scale of 2 or 3 should be a good balance (as per tooltip)
For 32 bit, have to use gzip. For this, Quantization Level needs to be adjusted. Zero will be lossless, have poor compression. 16 is the default, where there will be some loss but may be unnoticeable. Higher will be more compression but with more loss of information.
In all cases, processing time will obviously be longer.
RICE works well with 32bits. But this is lossy algorithm. However, as @vinvin said you will never see the difference as the compression is at noise level.
I know this topic is carrying on a bit, but FWIW, the tooltips say otherwise - that RICE and HCompress work only on integer arrays, which in SIRIL’ case is 16 bit.
Did it mean to say that RICE and HCompress will only do lossless for integer arrays? If so,
would be great if the text could be redone in the next version.