What's a good size/resolution for picture proofing?

Question

What's a good size/resolution when showing pictures to client using a online tool for proofing ?

I've noticed that 1350x900 and 72ppi is pretty good, considering image quality and size on disk.

What more do you suggest?

Answer 1

Short answer: it depends on lots of things...

• Is the client choosing which shots to pay for? Too high resolution and they might just steal them
• Does the client need to check for minor focus misalignments? Too low and this isn't possible
• Does the client always have a good internet connection? If lots of non-professional/non-technical clients, they may not appreciate having to download hundreds of MBs of photos
• Does the client want to spend a lot of time on this? If not, they may be happy to glance at low-resolution thumbnails
• How many photos would typically be in a set?

To me, proofing suggests not zooming in to 100%, or even zooming in at all larger than screen size, so a typical screen size (which may depend on the client/proofer) seems like a good starting point to specify an absolute upper limit.

Since it's online, my advice would be to have two viewing modes:

• Thumbnails, say 300 max dimension, which can be viewed as a group, and
• Previews, no more than 1200 max dimension (e.g. 6x4" at 300 PPI)

Have a look at how, say, Flickr sets up their users' photostreams; rows of photos around 300px high, which can be clicked on to view as a single large image. Facebook does something similar with albums (though both thumbs and 'full size' are quite a bit smaller on there). I'll bet 500px, imgur, and the countless other image/photo hosting services have similar album vs single-shot views and default sizes, so see how they do it, and what sizes they've chosen, and what upper/lower limits you think fits your application.

If you care about potential lost revenue by clients using the previews directly, you'll want to watermark the Previews quite noticeably, and/or limit images to say 600 px max dimension so they won't be usable as high-resolution prints or wallpapers. Even at 600px you can easily see the content of an image (all photos on Facebook had a max dimension of ~650 up to a year or so ago), if that's all that's required.