Float images should bear a caption and be referenced in the text. Please refrain from wording like the next picture or the following figure. Use cross references. Cross references are described Section 4.4

The usage of unreferenced images is discouraged. If you have an image you don't know how to reference either the image is unnecessary or your text is unclear.

The Documentation, both Core and Tutorials, is to be published both on the web and as printable matter. Dimension/resolutions should be, at maximum, as reported in Table 3.1 (see.. crossreferences!)

These resolutions/size guarantees that printed images won't be larger than 17cm and hence fills in a A4 printed page.

The usage of images larger than 800 pixel is anyway strongly discouraged since they are too wide for a confortable reading on a web browser.

Among Blender's Interface most prominent feature is that it's fully OpenGL and scalable. This is great but will sadly result in much disuniformities if many different users resort to screen dumps to show peculiar material settings, texture settings and the like.

To allow for both clarity and uniformity you should dimension the interface so that the RED slider in the material window is 18 pixel hight. This is what Blender produces if you use a 1024x768 screen resolution and press the 'home' button to set the default button size.

If you use a larger resolution, please drop down to 1024x768 for screen capturing. I hope noone out there has smaller screens!

Screen captures must come in a LOSSLESS format, so use PNG.

Inline images showing Blender icons are welcome and make description much clear. Since these are STANDARD images, please refrain from making your own, but download the complete set provided by the Documentation Board

Official Documentation is not a place for smileys. (humor is another matter, of course you can be humoristic!)