Re: [Gimp-user] Exporting files

[Burnie West <west ieee org>]

On 01/09/2014 12:50 PM, EGoldman wrote:
> I had a point and shoot camera that only shot in Jpeg so after I did all my
> levels and curve and contrast changes, I would always export as Tiff file so I
> would have a negative/master file of my pic.
>
> I have just bought a  Canon DSLR which I can now shoot in the Raw, my question
> is after I make my color corrections, how should I export the file so I have a
> negative/master?
>
> Any guidance would be so appreciated.
The principal advantage of RAW images is the amount of data.  Your jpeg files 
will have been compressed using lossy algorithms before the camera ever 
delivered them, and image data will have been lost. Exporting to PNG prevents 
that. TIFF may or may not lose image data, depending I think on the settings. 
Anyway, I usually export to PNG. I just did an experiment; I have a 5K by 6K 
portrait. The image exported to PNG is 10.3 MB, to TIFF it is 29.8 MB using 
packbits compression, uncompressed it is 117.4 MB. I think packbits is not lossy.