RAW Processing : Colour Depth

[dje]

I have the following options available for processing RAW files

1. Photoshop Elements 9 (which uses Camera Raw to open the RAW file and do the initial processing)
   
2. RAWTherapee
   
3. GIMP (which uses UFRaw to open the RAW file and do the initial processing)

With Elements and Camera Raw, the initial processing can be done with either 8 bit or 16 bit colour depth. However if 16 bit is used, there is limited functionality in Elements to do further processing (eg no layers) and the image can't be saved as a jpeg.

RAW Therapee seems to be fairly good freeware but it has no advanced features like layers etc. Therefore you have to use Elements in 8 bit mode for further processing.

GIMP is also good freeware but as far as I can see it only works in 8 bit mode ??

I assume that full 16 bit processing can be done with say Lightroom plus CS5 ? ( but I can't justify the cost)

In terms of final quality, how important is it to work in 16 bit mode all the way through processing until a final jpeg (8 bit) is produced ? I am not interested in large prints, only images viewed on screen and sometimes small prints.

Could anyone help me with my understanding of this issue please ?

Cheers Dave

[jiro]

I'll give you a bit of encouragement, Dave. Some very well paid photographers/photoshop artists like Calvin Hollywood prepares their portfolio using only 8-bit files in sRGB mode. You can access all the features of Photoshop when you work in 8-bit mode. Once you stay in using 16-bit mode you would lose the ability to use a lot of filter commands in Photoshop. The portfolio that I am talking of are also uploaded by Calvin Hollywood on the web to be viewed by his prospective clients. As long as you are starting from the RAW file you can definitely work with a lot of advantage in your hand. I can't speak for RAWTherapee and GIMP nor Elements but with Photoshop I can work in 8-bit mode and NOT complain at all. I am not a professional photoshop user so kindly take my word with a lot of grain of salt. Make that a bucketful.

[dje]

so kindly take my word with a lot of grain of salt. Make that a bucketful.

I don't think so Willie, I dont think so !!

Thanks for your comments. I may be concerning myself too much with this issue (not that I'm losing sleep over it )

Cheers Dave

[AlanP]

Camera Raw always processes in 16 bits. There is an option to output the files in 8 0r 16 bits. In elements you can perfrorm some operations in 16 bits including using any plug ins that operate in 16 bits. After exhausting your 16 bit oparations convert the image to 8 bits and continue with the 8 bit operations.

Alan

[Colin Southern]

As a rule - once you've made the major levels adjustments in a RAW converter, there's little to be gained in a subsequent 16 bit workflow for most normal processing.

Hope this helps

[dje]

Thanks Alan and Colin for your replies. I think I'm pretty comfortable with the situation now.

Cheers Dave

[Amhornedomd]

thanks for sharing this Colin, i didn't know this up to now.

[Colin Southern]

thanks for sharing this Colin, i didn't know this up to now.

Hi Abner,

No worries.

Basically, a 16 bit workflow gives us the potential to make bigger adjustments with less of a risk of banding and posterisation -- but as these "bigger adjustments" are best handled in the RAW converter, once we get the image out of the RAW converter and into Photoshop or Photoshop Elements (or in fact any editing program) there shouldn't be any big adjustments left to do -- and thus 8 bit workflows are generally OK.