which zoom level to trust for printing

[mel76]

Hi to all,

In psp , which zoom level gives me the accurate printing display?
Is it 66% or 100 %?

Before printing I'd like to see what it is going to look like on the paper.
To do this, should I zoom to 66% (a friend told me that 66% is the accurate printed size) or 100 % ?
Most of my photos are not sharp enough when I zoom to 100% so does it mean they won't look sharp when they are printed ?

Thx
Melih

[AndyStevens]

Hi Melih,

Unfortunately, you won't ever be able to replicate print quality onscreen - it's a physics thing due to screen resolutions.

I think you would be better off running some tests prints. Any image you view onscreen will be at 72ppi and you really need to be printing at at least 240ppi but preferably 300ppi. Either resolution will still look unsharp on the screen as you're viewing at 72ppi regardless (unless you use an iPad but then you're still way below printed quality).

Now, don't confuse ppi and dpi - ppi (pixels per inch) is the on screen digital file resolution and dpi (dots per inch) is the physcial printing resolution. Many printers use 600dpi upwards for printing but you can use as low as 150ppi depending on the printed size (the bigger the print, the lower the ppi that is acceptable).

As you can see, it's not that simple so do a test print and see what it looks like. If it's soft, increase the sharpening a little.

Hope that helps
Andy

[mel76]

Thx Andy,

I get what you explain here.
But just in terms of sharpness , is it more like %100 or %67?

[AndyStevens]

No worries Mel.

For initial sharpness, you really have to do that at 100%. If you choose 67%, the image will have to be interpolated down to fit to 67% which could introduce artefacts and appear soft.

For anything that I print, I always inspect at 100% on screen first to ensure sharpness is ok and all dust bunnies etc have been removed.

Cheers
Andy

[cosmicma]

i think you need to take the size and resolution of your monitor into consideration if you are trying to achieve in an odd sort of way what i think you are but first re read AndyStevens post it really does explain it's not that simple

ok now for my interpretation...

what i think you are trying to do is match what you see on the screen to be the same as you see in print
will this be printed at a3 a4 ? 6x4 ? 7x5 ? you don't say

so lets presume your printer is perfect and you want to print an a4 image but your curious how sharp its gonna be before committing ink to paper

the norm for checking how sharp an image is is to zoom in 100%
if the image looks a little soft as explained by AndyStevens there are various sharpening techniques to remedy this
we havn't even gone into image resolution and maximum print sizes before pixel stretching occours which softens a final print
if the same image was printed at 8x6 and 16x12 the 8x6 image would appear sharper how the sharpness of the image could be emulated on a monitor through magnification would ultimatly depend on print size and monitor size and resolution
for example a 22/24 inch monitor could show an a4 image lifesize ( 2 a4's on a 24" widescreen ) so in theory if i view the a4 page at 100% that is what i would see printed so if it looked sharp on the monitor it should look sharp on paper ( in a perfect world ) and so on

in other words iv'e gone a very long way to say
is it 100% or 67% ???
it doesn't work like that

EDIT...
ahh i see andy was typing at the same time

[mel76]

Ok, now it is more clear.
thx to you guys...

[AndyStevens]

no probs, glad to be of help.

something I meant to suggest, and kind of follows what cosmicma was saying...

Open an image, go to Image > Image size and make sure 'Constrain porportions' is ticked. Then resize the image to 6" x 4" at 300ppi. I've just done this and trhe resulting image, when viewed at 100%, is bigger than my 15.4" laptop screen. Now, go back to Image > Image Size and change the resolution to 72ppi and see what happens.

100% on screen is useful, but a bit bobbins really...

And make sure you don't save that image as 6x4

[GeoffWessex]

It's been a long-standing 'feature' of both Photoshop and Photoshop Elements that some zoom levels (magnifications) in the editing window are sharper than others. So maybe that's the same in PSP.

As far as i remember, 25%, 50%, 75% and 100% are accurate and sharp. The ones in between - 12.5%, 33%, 67% etc - are a bit fuzzy.

If that's what you mean.

Of course, none of it has anything to do with printing, just viewing.

[Forseti]

And just to add a bit more to this saga of zoom and sharpening. When editing a raw image in either LR or ACR sharpening is disabled until the image is viewed at 100%. When editing a jpeg image in Photoshop and one selects Filters > Unsharp Mask for example a pop-up window will appear with a section of the image displayed at 100%. View actual pixels, view at 100% or any other such terminology are, in effect, one and the same thing and is always the level at which sharpening should be applied.

[AndyStevens]

And they say you learn something everyday - didn't realise sharpening was disabled in LR and ACR until viewed at 100%. Thanks Forseti