Sensor size & viewing on monitor

[Shootist]

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I have been doing some thinking, I know that may or may not be a good idea, about sensor size, image resolution and viewing on a PC monitor.

Everyone talks about viewing at 100%, pixel peeping, and it has come to me that when you look at a image from any digital camera RAW file data converted to 300 PPi what you are really looking at is a image not at 100% but at 1000%+.

To view the image at it's true 100% you would need to set the RAW converter to the native 3xxx "X" 2xxx (depending on the digital camera you are using and base MP of the sensor) PPi setting.

 

Then again sometimes when I start thinking anything can happen.

 

Comments?

[luigi bertolotti]

Uh... it's easy to get confused about these questions of dot/pixels/inches... thinking of the question, and speaking about MONITOR viewing I would say :

 

- How we define a 100% image of a file ? To me, an image on the PC screen in which you have a precise correspondance 1 Screen pixel = 1 CCD pixel (RAW, of course)

 

- So, if your screen has, say, 1600 horiz. pixel, let's say that taking in due account the windows borders etc. you can display surely about 1500 pixel in horizontal.

 

- So a 100% image is a crop which "cuts away" a fraction of the entire frame so that the total horiz. pixel are about 1500 : from a 3916 horiz. pixel RAW M8 frame you have to cut away about 60% of the frame.

 

- Then, the PPI setting has to be set so that you "enjoy" your screen : given the above data onto an about 15 inch (horizontally measured) window, you can set a 100 PPI (1500/15) factor.

 

- and all the same in vertical, of course...

 

This is a brutal computation, but I think is a correct one. But maybe I can be wrong : don't know if the assumption "100%=screen pixel coincident with CCD pixel" is right.