Photoshop - 'Fit on screen' question (1 Viewer)

I have recently downloaded a trial version of Photoshop which I have been trying out and have found something that has me a little puzzled.
When I open an image it initially appears to be quite sharp on my screen and the image shows xxxx@25% RGB8.
However I normally like to enlarge the image to fill the screen and have noticed that when I select 'Fit on screen' the image appears quite unsharp and a bit blurred. When I do this the image shows [email protected]% RGB8.
This had me a little puzzled as I was convinced the original photo was very sharp and I never experienced this issue when I previously used Elements.
What has me really puzzled though is that if I select 'Zoom in' the photo enlarges even bigger ( 33.3% ) or more but still remains relatively sharp as I would have expected.
My question therefore is Why do my photos look blurred when I select 'Fit on screen' but look nice and sharp when I select 'Zoom in' and enlarge them even bigger than the 'Fit on screen' image ?

The only size to judge the sharpness of an image on screen is at "Actual Pixels." At this view setting you have a 1:1 ratio of one pixel in the image file = one pixel on your output device (your monitor.) This is why you really need a large display for photo work. The Actual Pixels command and its corrisponding keyboard shortcut (which will be your new best friend) can be found under the View menu on Macs and PCs. All other sizes are scaled interpretations of the image content. Evenly divisible sizes, such as 200%, 50% and even 25% can also show the image somewhat clear of interpolation artifacts, but sizes such as 22.9% for example will leave your image looking like it's been run across a cheese grater. Fit to screen is only useful when you are concerned with composition issues, rotation straightening, perspective/distortion correction and cropping. Photoshop is indeed a capricious beast, best of luck to you.

Ok thanks for the info which explains to a large degree what is happening.
I still think it a little strange though that I never experienced blurred images when using Elements to view photos that were enlarged 'Fit to screen' but I do with Photoshop.
This seems especially odd when you consider that both software packages are from the same company.
Like you say this if probably one of those quirks with Photoshop and I've still a lot to learn regards using it at the moment.

mookadabird said:

The only size to judge the sharpness of an image on screen is at "Actual Pixels." At this view setting you have a 1:1 ratio of one pixel in the image file = one pixel on your output device (your monitor.) This is why you really need a large display for photo work. The Actual Pixels command and its corrisponding keyboard shortcut (which will be your new best friend) can be found under the View menu on Macs and PCs. All other sizes are scaled interpretations of the image content. Evenly divisible sizes, such as 200%, 50% and even 25% can also show the image somewhat clear of interpolation artifacts, but sizes such as 22.9% for example will leave your image looking like it's been run across a cheese grater. Fit to screen is only useful when you are concerned with composition issues, rotation straightening, perspective/distortion correction and cropping. Photoshop is indeed a capricious beast, best of luck to you.

Click to expand...

The fit to screen is probably the worst viewing size in PS.

I find that working at 33.3% is a good compromise.