Matching InDesign and Photoshop Pixel Dimensions

Question

I'm attempting to use InDesign to determine pixel sizes of a baseline grid and typography that will eventually be used on a webpage. Since Photoshop doesn't have a baseline grid or a baseline grid snapping feature, I thought I might be able to make something work in InDesign.
Unfortunately I'm running into a problem, where pixel dimensions in InDesign don't seem to match up with pixel sizes in Photoshop. For example, with documents at 100% view in both Photoshop and InDesign, a 100px square appears larger on screen in InDesign than in Photoshop. It's as if InDesign is rendering the view at a different resolution than Photoshop.
Above you can see a square made at 42 pixels in InDesign viewed at 100% zoom (though InDesign insists on displaying the size as points) with the same square screen-captured and opened in Photoshop. The square is actually measured at 54 pixels.
How can I get InDesign to display the same pixel sizes as Photoshop?

Answer 1

True enough on both counts! Relative resolution and scaling is definitely helpful for print design (I learned early on what scale to view in order to preview onscreen at what would be actual physical size--the reverse of double-clicking the zoom tool now, I guess.)
But I see no reason why we can't have it both ways. Isn't that the whole point of "web" or "Digital Publishing" intent in document setup? Why not have Indesign switch to 1-1px scale when you create a document set to web intent? Wouldn't be any different, functionally, than what the script does, it would just revert to physical scale when I open a print document. Seems like it should be obvious that the preview scale when creating a web site should be 1 pixel is 1 pixel--my browser isn't going to display my website at 123.7% scale. Or that if you chose the "iPad" digital pub template, the display scale should be twice that of a (theoretical) Retina display iPad. It's functionally just a different number, right? That is, if I were writing a script, I could theoreticall specify any resolution I wanted to get the desired display scale.
Ok, so now I'm turning this into feature request, I know, and the question has been thoroughly answered. But it needn't be that complicated--all we really need is a place to CHOOSE what mode to opperate in, right? If Adobe really prefers not to open the output-intent-view-scale can o' worms, then why not leave an Acrobat-style resolution preference where I can type in a number? The obvious advantage of that over the script solution is that it's easy to set or reset.
Aside: while we're on the topic of having it both ways in regards to using Indesign for more than print work... Why not include the option to set the document color profile (most likely to sRGB) when I choose "web" intent in a new document dialog? Oh! And give me actual RGB black and white color swatches in "web" documents.
I'm just excited about the idea of Adobe taking a few more steps in the direction they've started with the whole document intent feature set in Indesign. A more inviting web design environment wouldn't in any way keep me from continuing to use Indesign for print work (all day every day). What is there to lose? Not like they're developing Fireworks anymore, and Indesign already makes more sense for web than Illustrator. ... I'm sure it's a HUGE internal debate at Adobe. Probably some Fireworks replacement app in the works that I don't know about.