As mentioned in this post
I finally got the opportunity to give the D30/Sigma combination it's first proper outing of the year at Manchester.
Overall I'm very pleased with the results I've been able to obtain but one (dare I say it) 'flaw' with this setup is a failure to focus at the short end of the lens. As an aircraft began it's take-off roll I would be zoomed out to 500mm gradually pulling back all the way to 170 as it passed side on to me and the push out to 500mm as it climbed out. However I began to notice that as I zoomed in to anything less than 250mm the lens would simply refuse to focus on the aircraft.
I then tried this by focusing on static objects and still the same problem. The camera is exhibitng no error messages and focuses fine throughout the range with my 28-80 & 75-300.
Anyone else experienced this and have a solution? Have I been a complete dufus and missed something blindingly obvious?
I'm wondering if this could be a low power issue? I only ask this as I've just tried the camera again focusing out of my window and it now focuses throughout the zoom range!
Yesterday was a beautiful day with great sun but my battery pack was a bit low on juice. Today with fully charged battery pack and pretty grey and overcast conditions it focuses very nicely thanks!
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