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Message: <blockquote data-quote="smurf.for.mark" data-source="post: 3500403" data-attributes="member: 63586">back again with some better news, after having my ior's pretty much messed up by to my knowledge? the last optical repair company left in the uk i was not going to send my zrak's for the same treatment!i have been busy with work but had a quiet day today and after some though set about fixing the zrak's myself...they had a few issues... mechanically, loose center hinge. optically, some prism lean with a little haze on the back of the prism in the right side. as you can imagine it is a little scary as i spent quite a bit on these and im under no illusions as to how difficult it is do!first thing i notice is there doesnt seem to be any concentric rings around the objective for fine collimation which for me is worrying!secondly there doesnt appear to be any provision for nitrogen purging?... i screw or other port?to fix the center hing i had to make a tool using some tool steel and two drill bits the correct size to fit the holes in the center hinge fastner at the front. i managed to turn it about half a turn and that seems to have tightened it sufficiently so thats one job done!to unscrew the objective i had to remove the beauty ring which is threaded onto the front plate after removing a locking ring (again i had to make a tool to fit) then unscrewed the objective bell using an oil filter wrench with leather padding. the front plate is held with a single screwnow i can see the gimble holding the prisms and noticed the front prism is positioned with concentric screws. knowing i have prism lean and having a couple spare prisms to see which way i need to rotate to correct i at least know which way i have to gofirst thing though is i have to clean the prism back which means removing the prism assembly! its held with three screws and once undone the whole assembly lifts out.after cleaning the prism back leaving the prisms in place i re fitted the prism assembly into the barrel. with the screws done up loose i refitted the objective lens minus the front plate to check alignment which was very close, after tweaking the position of the gimble with a small screwdriver prying on the gimble edge the alignment was good. i removed the objective and tightened the screws and re fitted the objective to check. i had to do this several times.regarding the prism lean, i new which direction i had to rotate it in so loosened one concentric screw slightly and tightened another until the lean was gone and checking collimation while altering the ipd and it seems to be spot on! the binoculars are vastly improved! much easier on the eye when using now and as far as i can tell just fine the sharpness seems improved now as well with both images aligned also luckily i managed to keep everything pretty clean inside so very pleased with myself!</blockquote>

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