>> Tuesday, 4 May 2010
Now that's a heading that verges on the silly, isn’t it?
I had a question today on “how do you uprez your files”. Here’s a little info. A little more than asked for perhaps.
Size is important when it comes to photography. The images have to be of sufficient size to be published. A frequent recommendation is that the “uncompressed” file size should be at least 48MB. What this means is that an 8-bit tiff file should take up at least that much space on the disk. Expressed in another way, this equates to approximately 3000 x 5000 pixels. If you are looking at a jpeg (jpg) then the file size will vary, perhaps between 8MB to 12MB. (If you need this is of course dependent on what you will use the photos for!)
Many cameras do not produce files of that size so you will have to make the files bigger (also called up-res, or up-rezz, or up-size or similar things).
Instead of just giving the simple answer I thought it could be worth while to explain in brief my full “developing” or processing workflow:
1. Shoot in raw. Always shoot in raw! (did you only shoot polarioids when using film cameras?)
This means that the photos must be processed after shooting. Yes, must. You cannot use a raw image as-is.
2. “Ingest”, i.e. move the files from the camera to the hard disks (yes, in plural. Backup is vital) change the names to your naming standard (important!) etc etc. I’ll skip the details of this.
3. Process the images with Capture One (a software from Phase One).
There are several different raw processing sw to choose from. The most popular is probably Adobe Camera Raw (ACR) that you get with Photoshop and Lightroom. My preference is clearly Capture One. My impression is that it gives better results and is faster to work with (speed matters too! Not only size. If you have a few thousand images to process it will rapidly make a huge difference).
However (and this is a big ‘but’): Capture One is difficult to get to grips with. But once you have figured out how it works, all the keyboard short cuts, commands etc it is really fast. And gives very good results. It's worth while to learn it.
Input to Capture One: raw file
Output: 16 bit (yes, 16) tiff file, in the original (camera) resuolution
4. Adjust the image in Photoshop
This may include additional colour/saturation adjustments, dust removal, cloning, etc etc. Or almost nothing.
The final step is to change it to an 8-bit tiff.
The 8-bit tiff becomes my “working original” from which I can make delivery copies. This is the file I put in my “develops” catalogue.
5. Make a delivery copy
This is where up-sizing comes in. If, for instance, a photo is supposed to go into a stock library like e.g. Alamy or my own BKWine Photography then it needs to be at least “48 MB uncompressed”. This, as explained above, means that the 8-bit tiff should be 48 MB. This tiff should then be converted to jpeg and sent to the library. Here’s what I do:
a) Up-size with Photoshop (“Image Size”) using the Bicubic Smoother option. How much you should upsize depends on the size of the original file and how big you need the result to be. If the 8-bit tiff is around 17MB (coming from a 6 megapixel camera) then you need to upsize around 173% to get to 48MB uncompressed. You will have to test to get the exact numbers right. (Note: sometimes it is said that you should upsize in 10% steps. Don’t!)
If the raw file is big enough out of the camera, you don’t need to do this. This is the case for some of the recent DSLRs (e.g. the Canon EOS 5D Mark ii) but for most cameras you need to uprez.
b) Save the file as a jpeg, quality 10 to 12 (maximum quality or close to maximum quality)
6. Send the file to the destination.
A note on sharpening: I never do sharpening, at least not for stock photos. I’m not a specialist on the technology, but there seems to be an consensus that sharpening is a bad idea. You should only do sharpening once you know how the image will be used (what kind of printing and what size) and you never do for stock. So, don’t do sharpening!
A note on noise: If you have used very high ISO (say, 800 or more) you may need to use some noise reduction. I’d recommend a dedicated noise reduction software to do that. You can also do it in Photoshop but I prefer e.g. Noise Ninja.
A note on organisation: You need to catalogue files with a DAM system (Digital Asset Management) but that’s a big subject in itself. I am currently looking for a new DAM solution since my old one (Extensis Portfolio) seems to have decided to leave the independent photographers’ market.