Pre-Processing and Processing File Types

[groberts]

I only caught up with Steve Richard's Stargazine Talk "Dark Art or Magic Bullet" and was interested that he strongly recommended continuing to work with FITS files after DSS and perhaps later with the PS native files - is there any reason evidence that this produces a better outcome or is it just personal preference?

For no particular reason I've always taken Tiff files from the DSS stacking pre-processing into PS and continued to work with TIFF throughout the PS post-processing until completed and need to export for the web etc.

Graham      

Edited September 24, 2020 by groberts

[symmetal]

While tiff can store multiple layers I'm not sure as to whether all the layer or mask attributes including advanced blend modes, layer linking and locking, etc. will be saved in the tiff file. If info will be lost when saving, Photoshop usually warns you though, so if you haven't had any warnings you should be OK leaving it in tiff. I imagine PS is more efficient in storing its own image data, so creates smaller files than tiff which is a more generic storage format.

Alan

Edited September 24, 2020 by symmetal

[groberts]

Thanks Alan, I tend to flatten image layers as I go along once happy with the result, so not sure that's an issue.  However, this has got me thinking and might at least experiment with other formats (FITS / PS).  I only went with Tiff as, I think, that was the default output from DSS when I started a few years ago and until now never questioned it.

Graham 

[sloz1664]

Hi Graham,

I have always used Fits files for my images, normally 16 bit, but as of late 32 bit. The fit file structure carries with it the astro details for that particular file and is usually called a Fits Header. If the bit data is the same for a tiff file and a fits file there should be no degradation between the images. In fact, StarTools, an excellent image processing programme, outputs Tiff files and not Fit files. 

 

Steve