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Old 03-06-2025, 04:51 PM
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bojan
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Join Date: Jul 2006
Location: Mt Waverley, VIC
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Quote:
Originally Posted by Leo.G View Post
How hard is it going to be getting the mirror adjustment spot on?
Trial and error I guess?..
If you are referring to colimation, there is none.. The mirror sits in its seat, not tightened, just touched.. so it is not deformed (hopefully)
And since this lens is going to be used for AP only, I am adjusting focus with Bahtinov mask on live screen. Focus is usually stable since the lens is small so it reaches thermal equilibrium relatively quickly.
For Solar Eclipse 2028, I am guessing I will adjust focus (with live view again) on some distant object on the horizon, before the event, when the temperature is already stable.

When I was adjusting focus on modified Canon 50mm F1.4 FD, I was also using live view, with the lens assembled but focus stops accessible for adjustment. so it was not entirely trial & error method :-)


Quote:
Originally Posted by Leo.G View Post
Have you had any luck with the other lens with the un-removable screw?
Not yet.. I postponed the Astron Reflex for the day I am less nervous :-)
I will try with hot air gun (and small nozzle) and your method (I have cold spray.. and butane gas can be used as well).. but later , maybe this week.
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