to the forums, deadhead!
Here's a link to my tutorial on OIl Dot Weathering--by the way, if you want to have this in "hard copy", the December issue of Finescale Modeler will have my article on this exact model and tutorial in that issue!
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A filter is the same as a wash in some respects, but in that it is a very,very thinned application of paint which is used the same way that a photographic filter would be used, as in a "Sienna" tint applied to a photo. You use a reallt thin application of paint to subtly alter the base coat. The "Dot Weathering method simply uses a wide palette of colors to effect a range of hues.