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Message: <blockquote data-quote="dantheman" data-source="post: 3348065" data-attributes="member: 32998">Stretching the limits ... ?Since I've been called out, as it were, on the Manx Shearwater distance topic, thought I'd best try and provide a little extra info (providing proof not so easy of course).Anyway, first yes, the ED50 is a cracking little scope ... <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" />Thought my eyesight was quite good, but after recent visit to opticians looks like it's 'normal' (20/20)Observer location - Pendennis Point, Falmouth. Birds were seen to be flying behind The Manacles off the east side of The Lizard. I'm sure I measured this as being 8 miles distant on the OS map at the time; however looking on googlemaps <a href="https://www.google.co.uk/maps/dir/50.143902,-5.0431353/The+Manacles/@50.1096763,-5.0781542,12z/data=!4m8!4m7!1m0!1m5!1m1!1s0x486b303e8c583915:0x495fdd792e8c51c!2m2!1d-5.05!2d50.05" target="_blank">https://www.google.co.uk/maps/dir/50.143902,-5.0431353/The+Manacles/@50.1096763,-5.0781542,12z/data=!4m8!4m7!1m0!1m5!1m1!1s0x486b303e8c583915:0x495fdd792e8c51c!2m2!1d-5.05!2d50.05</a>it only looks to be a little over 10km, ie 6.25 miles or so, which is a lot less (unless I've got my rocks off?) That probably changes things a lot?That probable error aside (can't check on the ground as I'm away at the moment), both Manx Shearwater and Balearic Shearwater can be relatively numerous on seawatches in season - used to seeing both, and with some overlap when both occur. On this occasion it was the end of the main Manx season and I was hoping for an early Balearic.The lighting was such that flocks of birds shearing would show a dark grey upperside, followed by a gleaming white underside as they caught the sun (the bright side more noticeable than the dark side of course). Pretty confident that I would have picked out a mid-phase (pale brown) Balearic if one had passed by. A dark bird could have been missed, as could a pale bird, but I was hoping the creamier underparts would stand out. Can't prove one didn't pass by as I was watching, but as I say, don't think an obvious one did. The proof would of course be in picking one out in the future - something to aim for?! And of course it's a case of id'ing birds that aren't rarities requiring a description - picking up on other id features (including even the different shape and length) maybe too much at that range!Manx Shearwater wingspan (from Collins) - 72 -82cm The width of the wing looks to be c.10% ie 7 - 8cm, but can't see this online to confirm. So how many arcseconds would that be at that range and magnification?Anyway ... <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /></blockquote>

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