100% image peeking

[Polar01]

I really did not know what to call it. I look at 100% in Photoshop as 1 inch on the on screen ruler as equal to 1 inch on a hand held ruler when held up and compared to the on screen, both are the same length. For me as I use a 32 inch screen the little percentage showing in the lower left corner is only 26 point something % and the image is full size, that is 1 inch on screen ruler same length as 1 inch on hand held ruler.
So I guess the question is when someone states to zoom into 100% is that really zoom into until you are full size?

Cheers: Allan

[xpatUSA]

I really did not know what to call it. I look at 100% in Photoshop as 1 inch on the on screen ruler as equal to 1 inch on a hand held ruler when held up and compared to the on screen, both are the same length. For me as I use a 32 inch screen the little percentage showing in the lower left corner is only 26 point something % and the image is full size, that is 1 inch on screen ruler same length as 1 inch on hand held ruler.
So I guess the question is when someone states to zoom into 100% is that really zoom into until you are full size?

Cheers: Allan

A subject often discussed on another forum that I infest regularly.

There, 100% refers to viewing an image whereby one file pixel maps to one screen pixel with no "sizing to fit", no zooming in to where one file pixel maps to several screen pixels and no zooming out to where one screen pixel maps to several file pixels.

For some reason, viewing at a true 100% is often derided as "pixel-peeping", I've never understood why. For me, a one-to-one correspondence between file and screen is truly "WYSIWYG" - any other view has been degraded by interpolation.

I do make an exception when analyzing an image. My viewer can be set to "nearest neighbor" re-sampling as opposed to "smoothed" viewing. That means that, if I view at 200%, 400%, 800%, etc. then 2x2, 4x4, 8x8 on-screen pixel blocks represent one file pixel ... can be useful at times. Perfect for viewing the havoc wreaked by JPEG compression, for example.

[Manfred M]

Alan - Ted's interpretation is the same as mine; one pixel in the image file = one pixel on the display

I've never thought about is as a physical measurement, but when I do the math, my main display runs at about 108 pixels per inch.

I also agree with Ted regarding pixel peeping. 100% is the only time we can truly see the image without any interpolation by the software I am using. I always do my input sharpening and process sharpening at 100% size.

[DanK]

+1. I have always used the term to refer to a 1:1 mapping between pixels in the file and on the display.

I routinely start sharpening at 1:1 but then reduce magnification to check the appearance. 1:1 is also important for noise reduction.

[pschlute]

I really did not know what to call it. I look at 100% in Photoshop as 1 inch on the on screen ruler as equal to 1 inch on a hand held ruler when held up and compared to the on screen, both are the same length. For me as I use a 32 inch screen the little percentage showing in the lower left corner is only 26 point something % and the image is full size, that is 1 inch on screen ruler same length as 1 inch on hand held ruler.
So I guess the question is when someone states to zoom into 100% is that really zoom into until you are full size?

Cheers: Allan

I concur with the other answers her both on the definition of 100% view and its usefulness.

A picture opened on a computer has no physical dimensions only pixel size x*x

When you edit an image in PS you can use the Image Size menu to change the pixel dimensions (re sample) and/or specify a physical size for the picture. You would only do this for printing purposes. The third part of the equation (again only important for printing) is the ppi (pixels per inch) setting. Have a play with an image changing these settings and you will understand the process better. You will also discover what can and cannot be changed without altering another setting.

As an example if I want a print 24"*16", and my printing company require a file that is 300 ppi, I know I have to supply them with an image 7200 * 4800 pixels at 300 ppi. The physical size of my image is a by-product of those two numbers.

Last thing to remember is that two different screens will display any image differently when asked to use 100% view if they have different screen resolutions. Two identical screens for example will display a 100% image differently if one is set to 2560*1440 and the other to 1920*1080