When I know I need to do a lot of processing of a RAW file I open it at 16 bit in Photoshop. Now when I’m done and need to save as jpg to put on my photoblog I first convert to 8 bit and ’save for web’ as a jpg.

This often causes the photo to go very ‘flat’. A lot of the colour and lumination is lost. I understand 8 bit is a lot smaller colour space than 16 bit, but it still should not be that different. For example I can open the jpg and increase saturation and contrast and get a lot closer to what it looked like before I converted the 16 bit file.

Do you have a work flow to avoid this?

Thanks,
Jesper Garde

Julien :
Yes, your problem is a very common one and has nothing to do with 8bits or 16bits .
You probably edit you picture in another profil than sRGB which is the default format for web export. There are good chances that you edit it in AdobeRGB or ProPhoto RGB which is a good thing, but you need to convert it to the standard web profile (sRGB) before saving it.
1. Save your source PSD file
2. Flatten picture (Layer > Flatten image)
3. Resize picture to the desired web format (Image > image size)
4. Convert image color profile (Edit > Convert to Profil …> Destination Space : sRGB IEC61966-2.1) (note that you can see in “source space” the profile you were using)
5. Convert image to 8 Bits (Image > Mode > 8Bits / Channel)
6. Use “File > Save As” instead of save for web (save for web is more a web designer tool), you will preserve your EXIF metadata
Voilà!

Julien : Yes, edit in 16 bits :). If you are talking of JPG artifacts then shoot in RAW.

Julien : I take all picture in RAW (color), results are due to the conversion and post-processing under photoshop, I will post a black and white tutorial in the near future, but right now I don’t have enough time

Fantastique petit tutoriel que tu nous présentes là! Je vais le conseiller à plusieurs amis graphistes et photographes. Continue ton excellent travail comme photographe et comme rédacteur de ces bons petits tutoriels :).

P.S. Petite rectification à débattre: Je suis graphiste et selon mes cours de couleur, l’oeil humain ne discerne environ que 200 tons de gris, du noir au blanc.

Julien : Merci pour cette info Olivier, effectivement ça reste à débattre mais je n’en ferais rien puisque les diverses sources que j’ai pu voir à ce sujet disent toutes des choses différentes et semblent être sûres qu’elles ont raison … mais c’est pas bien important

Julien : I try to have the less possible real picture. Most of the time I only have my original as the first layer and adjustment layers above it with masks. However, sometimes, I need to duplicate the original for some specific destructive filters like denoisers.