the size is ridiculously small compared to what it should

[MiniSimit]

Hi,

Why when I create a new file in Photoshop or import a new image, even if the zoom is 100%, the size is ridiculously small compared to what it should (the 500x500 seems like about 100x100)?

Thanks.

[davescm]

Are you using a screen with a high pixel density?

100% zoom is not a physical size, at 100%  Photoshop maps 1 image pixel onto 1 screen pixel. So the smaller your screen pixels the smaller physical size of the image on the screen.

Dave

[D Fosse]

You have a high resolution display. Photoshop displays correctly, the other applications don't. In Photoshop at 100% zoom, one image pixel maps to exactly one screen pixel. You can measure this out against your display's actual pixel resolution to check.

Most other applications don't have the same strict requirements for accuracy, so they scale images to 200% to compensate. This makes everything display at the physical size people are used to from traditional displays. But it's not accurate.

Edit: Dave beat me.

[rayek.elfin]

https://forums.adobe.com/people/D+Fosse  wrote

Most other applications don't have the same strict requirements for accuracy, so they scale images to 200% to compensate. This makes everything display at the physical size people are used to from traditional displays. But it's not accurate.

Whether Photoshop's display behaviour in this is correct or not, is up for discussion depending on the job and user perspective.

The key solution that is missing is a view option similar to the pixel aspect ratio: when the designer must design for retina screens X0.5, x2,x3,x4, custom setting, etc. it would be very useful to have a similar view option that displays the pixel density of the design as most other applications (such as a browser) and how 1 pixel "behaves".

[D Fosse]

rayek.elfin  wrote

Whether Photoshop's display behaviour in this is correct or not, is up for discussion

No, this is actually not up for discussion. 100% means one image pixel to one screen pixel. That is the only way to reproduce the file with absolute accuracy.

Anything else is scaling. So let's just call it that.

If we all had high resolution displays this issue wouldn't even exist. All this is about finding workarounds for displaying files on displays of very different densities. Likewise, the issue didn't exist five years ago when all displays had roughly the same density.

This is a display property, it is completely out of Photoshop's realm. A pixel is a pixel, it's just a data point. It has no size.

[mglush]

Hi!

I just noticed one thing in your image. Yes, you have a 500 x 500 pixel image, but your resolution is set to 300 pixels per inch. So....the image will show up on your screen small because of it being 100%.

[rayek.elfin]

PPI has nothing to do with the display size on the screen in Photoshop.

[D Fosse]

Pixels per inch is strictly a print parameter.

On screen, the image pixels align to the screen pixel grid, and the screen pixel density is the effective resolution.

On paper, such a grid does not exist - so one has to be invented. Otherwise physical print size would be undefined. This grid is defined as pixels per inch.

[rayek.elfin]

https://forums.adobe.com/people/D+Fosse  wrote

Pixels per inch is strictly a print parameter.

On screen, the image pixels align to the screen pixel grid, and the screen pixel density is the effective resolution.

On paper, such a grid does not exist - so one has to be invented. Otherwise physical print size would be undefined. This grid is defined as pixels per inch.

I would amend that answer a bit: knowing the PPI of a given mobile device and the size and height allow you to calculate in which density range your assets should be prepared at: x0.5, x1, x2, x3, x4, etc.

Strictly spoken PPI is no longer a print-only unit these days. DPI *is* strictly a print parameter, of course.

As you can tell, even Google gets it wrong: they insist on DPI while that only makes sense in relation to print (unless they assume DPI means "density per inch". It should be ppi, in my opinion. It is quite disheartening to see that even design software like PhotoLine and Affinity Photo get it wrong, and use dpi to indicate ppi.

Anyway, to calculate exactly what pixel resolution you need for your assets, DP is a unit that was introduced a while ago. A dp is equal to one physical pixel on a screen with a density of 160. To calculate dp:

dp = (width in pixels * 160) / screen density

...which means we need to know the screen's PPI (density). That is why PPI is no longer a print only parameter - it is essential to know any given screen's PPI density before we can decide what resolution our assets should be, and how many variants we require.

To simplify matters, the specific value will fall in a certain range (see above): ldpi, mdpi, hdpi, xhdpi, xxhdpi, xxxhdpi,...

Used to be so simple in the old days: 1 pixel represented 1 pixel on the screen. At all times. If you ask me, bitmap images will have to be replaced by something different at some point. Not quite sure what that would be, though. Perhaps a fourier-based format? Catching the actual wave information in a file (similar to a hologram), and the output device automatically decodes that information to its native resolution?

Anyway, read up on it here:

Supporting Multiple Screens | Android Developers

Units & measurements - Layout - Material Design

[D Fosse]

A "display pixel" is a scaling formula, used as a workaround to compensate for different screen densities.

This kind of argument forgets that Photoshop isn't used only by web designers, it isn't even used primarily by web designers. To a photographer, someone in prepress, a forensic worker, this argument makes no sense. If Photoshop behaved this way, it would be useless. It wouldn't be reliable.

So yes, ppi is still strictly a print parameter. Photoshop cannot do any "hidden" additional onscreen scaling to satisfy a very small group of users. It has to stick to the actual pixels on the screen. 100% is still 100%.

[rayek.elfin]

Then why have an aspect ratio view option to satisfy a small group of video professionals?

Mind, I am just playing Devil's Advocate for all those web and screen designers who use Photoshop. I would argue against the use of Photoshop for web and screen design work myself.

And regarding ppi being a print parameter only - let's agree to disagree. There are more important things in the world.

[D Fosse]

Because pixel aspect ratio is an option, well tucked away unless you specifically need it.

The requested onscreen scaling to conform with browser hacks, however - that would not be optional. And as a result cripple the app for everyone else.

In fact there is such an option already. It's called View > 200%. That should at least work for retina.

[davescm]

Perhaps there should be an option in the View menu, underneath Pixel Aspect Ratio, that could be called something like "Simulate browser scaling". Within it. a default option of OFF but additional options of 0.5x, 2x 4x . In reality it would just be a multiplier on the zoom control, so should be easy to implement (he says as a user not a developer ).

I doubt folk would like it though as they don't seem to like the look of 200% zoom - even though that is doing what the browser does. Plus of course different browsers use different scaling algorithms.

Dave

[D Fosse]

Yes, in principle it could be done that way - View 200% works fine, but now with 125, 150 etc there should be more options.

Some strange psychology at work here. Even though it's been demonstrated here that Photoshop view > 200% does a perfect pixel doubling, no resampling or softening whatsoever. They just don't "like" it... I suspect browsers have some "sweetening" algorithms to make the image look pleasant and agreeable, if not truthful. I strongly suspect Safari has.

[davescm]

Someone, I wish I could remember who,  did some comparative tests a few months back in the "back room". There were some fairly significant visible differences between browsers.

Dave

[rayek.elfin]

Thank you Dave, that's what I had in mind as well - similar to the aspect ratio view setting.

And yes, 200% works fine; yet it is the perception in users' minds that counts. That is why the best UX designer in the world designs a GUI that still needs to be tested with real users, and their preferences taken into account.