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Message: <blockquote data-quote="CliveP" data-source="post: 3415958" data-attributes="member: 85835">I think I sorted it.Seems it was collimation and the screws are for adjusting but it's an awkward system so I can see how it could easily be out after manufacture assembly or maybe a knock of some kind but the 4 screws seem to hold firmly so I doubt this.I still have to see how they fare outdoors but from indoors I've been able to use them without getting any further ache and they are just all-round better. More equal sharpness in both sides and much better focus with resulting sharp image and I seem now to be able to use them with a wider ipd even fully extended so fuller view and eye positioning seems to have improved so a lot to be gained and lost with collimation.I actually adjusted both sides in the end and I also swopped eyepieces and prisms between barrels to see if I could sort out the slight softness in the right side and I seem to have sorted that also.It's easy to see how they could have been collimated a bit out during assembly as it is a very fiddly system that can easily become off until everything is tightened and even the final tighten can knock them out a little again so I spent a lot of time getting it as best as I thought it could be and I think I got it which is actually pretty good so I'm pleased with that and glad to know a bit more about it but that should be it firmly set now.I accidentally touched one of the prism surfaces and in trying to clean it some smear is left so I should have been more careful but really it's just cosmetic and not affecting the bin. Once you get anything on a prism its basically impossible to get it factory clean as far as I know especially these caged roof prisms.Tomorrow I will replace the leatherette (after checking them outdoors first just in case they could do with another tweek or something weird happens with them?) as they came off without damage and that will be that. No visit to Pentax required I expect.Not recommended to do this on your best bins. This pair are a spare I bought cheap - probably sold by some-one who got eyestrain with them - so no real risk to my attempting this repair and I could always have sent them to Pentax to get professionally serviced and still can but I expect it's about £60 min for them to look at it so seems I will avoid that for now. I'll try and get a quote for info anyhow but way more important is that I do seem to have made an improvement to them from pretty painful and difficult to use for long to good or very good.So if they work well outdoors in a real test and I don't see why they shouldn't then that will be fantastic. I may even perform a similar op on some of my other bins just to fine tune them remembering to be extremely careful with the prisms next time athough I managed to have no problem with the second prism or any of the lenses so all in all I think an improvement and worthwhile. It's actually quite good fun but a bit of a puzzle.</blockquote>

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