Thank you for your suggestions. I'm not skillful enough to build my dedicated collar.
I tried with an ebay collar for another lens (one 400mm) lens that is thinner than the collar. I have not found the right material (flexible enough to be inserted in the collar and stiff enough so that the lens does not move ) to fill the remaining space.
Originally posted by excanonfd 3. Go to an auto supply store and buy an assortment pack of sheet gaskets (I bought from a local auto supply store, 4 sheets, thickness from 1/32 to 1/8 inch synthetic and natural cork).
Are the cork sheets OK (I've seen on ebay 1.5 and 3mm thickness)? Auto shops in the neighborhood not have.
Another problem is that for some long lenses there is no right space for the tripod collar. Then it would be useful a Manfrotto support. It is at a reasonable price, but I mainly use Arca Swiss fastening system. Is there something similar in the same price range, but Arca Swiss system? I found
this but it seems that adjustments are not so flexible than the Manfrotto support. Other alternatives?
---------- Post added 01-07-16 at 02:48 PM ----------
Originally posted by pepperberry farm almost night and day, vs the K300... the K300 is much more prone to CA than the A 400.... the handful of shots I've been able to get with the A 400 before winter set in are worlds away from the K300's performance...
Indeed A option is better, but it is harder to find (now I do not see for sale) and a higher price.