If you’re not calibrating your monitor and proofing with profiles from your printer you’re likely facing a long, painful road to “good” results...
If you want accurate colors, calibrate, profile, proof. On Sun, Jul 12, 2020 at 5:48 AM JLuc <j...@no-log.org> wrote: > Hello > > I'm using gimp and scribus to produce CMYK PDF > and i have issue with the photograph rendering of the printed books or > magazines. > > The original image files come from various cameras or smartphones > and lots of différente photographers, none of them being professionnal. > They all are RGB and many of them are not technicaly perfect > but at least i manage to get high-enough resolution pictures. > The issue is with colour rendering : > many of them are printed too dark, > and the dark parts are over-dark, flattened and with no details. > > AFAICT my scribus settings for colour management are OK (ICC profile...). > I havent a calibrated monitor. > What is see on screen is very nice - or at least nice enough - > Only printing is the issue. > The industrial printer i send my PDFs to prints on offset paper > - which i was told adds 2 or 3% to the red channel. > When i print localy on my deskjet printer, i kindof reproduces the "too > dark" effect, > which can help me "debug" and improve the rendering. > > When scribus displays the "out of gamut" areas, i see that much of these > pictures are out of gamut. > Bringing these picture more "in gamut" could help. > How can i achieve this ? > > EG this public domain picture https://pxhere.com/en/photo/1575227 > This one is not dark overall compared to others. > I can see the tomatoe are a bit dark but overall the picture looks bright > and balanced enough, > or at least there is a clear color contrast between tomato and salad > colors. > Dont you think so ? > When printed, both the salad and the tomato looks much darker > and there is no more contrast betwen tomato and salad. > I tried editing this photograph with gimp so as to improve print : > - selected tomato red area with progressive selection, boosted the red and > calmed down the blue and green > - selected the salad green area with progressive selection and added some > saturate effect > On screen the result is better, brighter. > But when printed, it is only very slightly (allmost not) improved. > > Another example picture is here : > https://pic.infini.fr/40kyb5S0/L6oygOf7.jpg > This is not so good a picture. > It's been edited a bit but that's not enough. > The dark part (door and water) are dark but we can see details in them on > screen. > When printed, these dark parts look flat dark brown-black with no details > at all. > > How can i improve that ? > > JLuc > > _______________________________________________ > gimp-user-list mailing list > List address: gimp-user-list@gnome.org > List membership: https://mail.gnome.org/mailman/listinfo/gimp-user-list > List archives: https://mail.gnome.org/archives/gimp-user-list > -- https://patdavid.net GPG: 66D1 7CA6 8088 4874 946D 18BD 67C7 6219 89E9 57AC _______________________________________________ gimp-user-list mailing list List address: gimp-user-list@gnome.org List membership: https://mail.gnome.org/mailman/listinfo/gimp-user-list List archives: https://mail.gnome.org/archives/gimp-user-list
