I'm a photographer looking for a good (detailed) resource that will inform me of specifically how I should be saving my images for print/online

Question

I've been working in photoshop for years but I've always gotten a bit lost on exactly what size I should be saving my photo's for optimal quality.
I basically need a good website that will go over all the aspects of saving images as a photographer, but if you can answer these questions that will also help.
• What size/resolution should I save if I am giving the client images on a disk for them to print?
• What size/resolution should I be saving photo's just for online viewing?
• How come when I place my image (saved at 4in x 6in) into a new document that is (682px x 459px) the picture is pixelated?

Answer 1

Perhaps the best resource for all things digital media related, especially when it comes to best practices in the industry is
dpbestflow.org
Specific answers to your 3 questions:
-generally, 300ppi at the final print size is good enough in most cases. If they are printing the image very large, like a poster or billboard image, then the print size at a lower resolution can be acceptable since it's being viewed from further away. Either always get the specs from the printer for what size/resolution they require, or just give them your full-sized original image, since that's all the pixels they can possibly have to work with.
-depends on every individual's monitor settings. If you supply an image that is HD-sized at 1920x1080, and they're using a monitor with a resolution at that size or greater, the whole image will fit on their screen. If their monitor resolution is smaller than that, your image will be bigger than they can display. Browsers, website coding, monitor resolution, all factor into how these will display on each individual computer. If you want the whole image to display within a browser window then you'll want your total pixel dimensions to be smaller than the average person's monitor resolution (unless you want them to be able to zoom in and see all the detail of your full-size image, then you would upload the full image and let your website do whatever it does to display smaller/thumbnail versions which can then be clicked on to open up the full-res version. Note, the actual resolution, e.g. 300ppi, doesn't factor into monitor display. PPI means it will PRINT that many pixels per inch of paper, and has nothing to do with how it will display on monitors which only concern themselves with pixel dimensions.
-682x459 is a rather small size. Of course it will lose detail. Just imagine if you scaled your image down further into a 10x10 pixel image. You'd have 100 pixels to make up all the detail in your image. Lots of detail will be lost since you've got a lot fewer pixels to make up the image.