I own and use all 3. WA G-Claron's are a huge double gauss 4 element 4 group lens. Trouble is they're giant and don't really cover any more than the tiny G-Claron will in the same length. G-Clarons are listed at 64 degrees but when stopped down past f22 they actually cover about 82 degrees. You can use a 305 G-Claron on an 11X14 camera and it would have lots of movement on an 8X10. Repro Claron's are dialyt. 4 element 4 group and to answer your question, a 305 has a circle of illumination far past it's useable "coverage" circle. Schneider didn't put a mechanical vignette in. So on an 8X10 you'll see an image on your 8X10 screen but when you get out to the edge it falls off super quick into mush. I don't consider my 305 Repro Claron useful for 8X10 even though it covers. A 355 Repro and even better, a 420 Repro-Claron are fine 8X10 choices. For 305 though, look for a G-Claron. Avoid the WA G-Clarons.