I recommend the InDesign workflow to everyone doing this kind of creative. The speed with which you can create an accurate layout in ID (not to mention ID’s type engine) is jaw-dropping to someone who’s only used Photoshop. Several of my friends have the maxillary bruises to prove it.
Under the hood, in the dark recesses of your system where only low-level functions hang out, some minion of the OS is telling InDesign that the resolution of your monitor is [x] pixels/inch (a number that may or may not be accurate).
InDesign has with this manic fixation that if you set your document dimensions in px you really meant points. So InDesign goes through the marvelously convoluted calculation of converting your document dimensions in pixels to a size in inches, then converting that (using the pixels/inch value passed to it by the OS) to a new pixel count. If the px/in value from the OS is valid, and you’re planning to print your document, the 100% view works reasonably well. If you’re targeting the web, it doesn’t.
You could work around this by telling your OS the blatant lie that your main display is 72 ppi. (Pray that it never finds out, because it will probably sue for divorce.) Other things in your system use that value that you probably don’t want to alter, but if churning out MPUs is what you spend most of your time doing, it’s certainly worth a try. In fact, if the px/in value being reported to your OS is flagrantly wrong now, you may get a far better result in general.
A compromise might be to zoom out one click from “100%”. It may not be exactly the size you see in Photoshop, but it may give you a better look at it.
Having said all that, the actual visual dimensions of your MPU are going to be so different on each of the many screen sizes out there (especially mobile devices) that I wouldn’t consider it worth the effort to try for some exact value. You might want to give yourself a week to get used to ID’s concept of 100% before you decide you really need to change it. InDesign’s way of doing it isn’t necessarily wrong unless you’re targeting an exact, known display; it’s just different. Because I use this workflow for everything from web banners to outdoor electronic billboards, I’ve never paid much attention to exact size. An electronic billboard display can be 60 feet wide. The artwork is 1400 pixels (no kidding!), so a “100% view” is pretty meaningless.
It’s probably more worthwhile to get several displays of different resolutions hooked up. What looks about right on your 110 ppi professional screen might look positively clunky on a generic 1280×1024 screen but wimpy on a high-res smartphone.
