BirdForum is the net's largest birding community dedicated to wild birds and birding, and is absolutely FREE!

Register for an account to take part in lively discussions in the forum, post your pictures in the gallery and more.

Reply to thread

Message: <blockquote data-quote="Cosme" data-source="post: 2971874" data-attributes="member: 118064">Rui, to me that CA at 25x is to be worried -in fact is to be worried in the APO too- look at the bricks distorsion, i repeat, only at 25x ... noticed the semi apo has the Pentax on it while the APO has the william optics ... though the pentax are better, if you put the WO on the semi apo and the pentax on the APO, well, what can i say ... and finally, the APO is FK61 glass, not a typical FPL53 we find in almost APO scopes. So the gap is even closer.This is taken with the BT81 at 27x (hyperion 17mm) compare one with another<img src="http://www.davidesigillo.eu/images/tele/hyperion17.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /><a href="http://www.davidesigillo.eu/test_vixen81.html" target="_blank">http://www.davidesigillo.eu/test_vixen81.html</a>Also, i finally get reply for the BT81 owner who confirms it can reach 50x without any loss (except some bright of course) compared with smaller mags. No one of the four or five APM owners i ask give me that performance chance by a long way, that said, he was very explicit that always with very good ep's ... the expensive ones forget about the 50 euros ep's ... so put it on your budget ....So maybe with some filters you can push it a little more, or maybe without it getting some acceptable CA.Cost the same, weight half, perfomance better ... my bet for terrestrial, would be the vixen.</blockquote>