Image scaling by browsers

Some web browsers come with (wretched) default settings that let them "rescale large images to fit in the browser window" as they call it. Unfortunately that default setting will prevent you from seeing our wallpapers at 1:1 scale at the bottom of our wallpaper viewer page.

Firefox

Below is a screen shot of the preferences dialog box of Firefox. Arrows are showing the check box that must be unchecked to disable the feature "rescale large images to fit in the browser window". The menu leading there is Edit > Preferences > Advanced.

Netscape

Below is a screen shot of the preferences dialog box of Netscape. Arrows are showing the check box that must be unchecked to disable the feature "rescale large images to fit in the browser window". The menu leading there is Edit > Preferences > Appearance.

Windows

On Windows XP boxes, the OS DPI setting may also have an influence. It seems that IE considers 96 DPI the default. If your DPI setting is different, IE will probably rescale the images according to its taste. It is possible that some notebooks are coming from the manufacturer with an OS DPI higher than 96, e.g. 120 or more. With such settings, all the images will be rescaled. Not only those which are too large to fit in the browser window.

Don't ask me where in XP the setting of the 96 DPI can be found, I don't have an XP box, but if you can tell me and send me a screen capture, I may add it to this page.

You can read more about bad scaling at this blog. According to this blog, I understand that Firefox under XP does not consider the OS DPI and not rescale when the OS DPI is something else than 96. Of course the check boxes mentionned above are a different story.

Scale marks test image

To check if your system is rescaling all the images (big and small), just have a look at following scale marks test image. All the lines of the scales should be clearly visible and exactly of the same width. I mean the alternating black lines and the white lines of any scale are exactly of the same width. One pixel for the 1st scale, 3 pixels for the 2nd scale, 5 pixels for the 3rd scale and 7 pixels for the 4th scale.

If some lines look a little thicker than others, your system is rescaling. And it is rescaling badly. If some characters are looking bold while others are not, your system is rescaling. If parts of a character are looking bold while the rest of the character is not, your system is rescaling. If some characters are looking shrunk or faded, your system is rescaling. (Either characters of the blue text, the red text, the black text or the white text in this 240 x 240 pixels test image).

Only in cases where your system is rescaling precisely to 200 % or 300 % etc, the image below will look clean. In cases where your system is rescaling let's say to 75% or 125%, the image below will look ugly.