Hello! I'm a bit late in joining in, but IMHO, a 300mm Artar Red Dot or APO dosen't have the coverage for 8x10. I am basing this on my own 14"(360mm) APO Artar which covers 8x10 with very little wiggle room. Even the 300mm Nikkor M is--once again IMHO--painfully tight though some people do just fine with them. I would opt for the 305 G-Claron is you want an affordable APO lens in that focal length. ------Cheers!