Hi,
this subject is bound to come up eventually so here is the pre-emptive strike.
1 - Straight thru scopes are easy to aim, and use in hides. However they are awful for watching raptors flying over because you have to duck down to look up .
2- If sharing this design of scope with people of wildly differing heights much adjusting of tripods is needed and wastes time getting groups on birds.
3- Aiming an angled scope takes getting used to but becomes second nature fairly quickly. Angled scopes however are not so good on hide shelves as you have to lean over the top. It's easier to stand and keep your tripod up.
4- With an angled scope birds in flight are easy to track as they fly over because you look forward to look up . If you have a group of people of differing heights wanting to see a particular bird it is easy to lower the tripod head and everyone looks down into the scope to share.
5- Angled scopes are arguably better in the rain because your body shields the lens - handy on sea watches too.
6- Angled scopes mean ( in many cases) that you don't extend the tripod central column as far up- so viewing ( and digi-scoping) is more stable.
:))
S
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