Extracting Part Of A String

we have a database with a lot of products in it. and for some reason one fo the feilds is set up like "<img src="images/something/image.jpg" />". they should be set up without the html but because of the way they are set up theres no way i can use them outside of the root directory.

I need a way to just pull the first 10 characters off the string. which would be the <img src=" part, and then pull off the last 4 characters " />. so that i am just left with images/something/image.jpg.

I can sort of get the first part to work by using Mid(string,10)

but how can i remove the last 4 characters?

in php the function would do the ending characters if you made it a negative number. but Mid(Mid(string,10),-4) doesnt seem to work.