Charlotte-- By far the easiest way to is to always keep a scale in the original picture; then there is no chance of losing or changing the scale. I also find a scale is helpful for focusing the picture, as long as you keep the scale in the same relative position to the specimen every time.
You could buy an expensive micrometer, but for large specimens we just print a paper grid. There is a very nice web site that lets you print many kinds of graph paper (squares, dots, lines, diagonals) to any size: http://incompetech.com/graphpaper/ Use a laser printer to make the lines very sharp. You can also print onto transparent plastic to make the grid waterproof. Put a piece of this scale in with the specimen, or put a sheet under the dish the specimen is in. I don't know how big wolf spiders are, but hopefully this will suit them. Regards, E.E. LeClair ____________________ Elizabeth E. LeClair PhD Associate Professor Biological Sciences DePaul University 2325 N. Clifton Ave. Chicago, IL 60614 USA 773-325-7462 773-325-6595 (fax) [EMAIL PROTECTED] On 10/30/07 9:48 AM, "morphmet" <[EMAIL PROTECTED]> wrote: > hi ! > > I just started a study on wolfspiders (genus Hogna), I want to measure > some morphological features (carapax,legs) but I'm also interested in > the shape from for example the carapax and the position of the eyes. I > think to use Tps. > Untill now I didn't find any related research on this topic (measuring > spiders). > > When I want to scale the pictures, do I have to take a picture of the > desired object and then from a measuring rod ? (but then I have 2 > pictures, and I will have to photoshop the rod to the first > picture..., isn't there an easier way ?) > > Thx for explaining to a fresh starter ! > > sincerely greetings > > Charlotte -- Replies will be sent to the list. For more information visit http://www.morphometrics.org
