I have done longer tests than that in the past.
e.g. the Tamron 200-500mm on APS-C (=800mm equiv):
http://www.opticallimits.com/canon-eos/2...rt--review
However, this was barely manageable.
Since this is possible outdoors only, this could be done during winter time at best (on a day without wind).
e.g. the Tamron 200-500mm on APS-C (=800mm equiv):
http://www.opticallimits.com/canon-eos/2...rt--review
However, this was barely manageable.
Since this is possible outdoors only, this could be done during winter time at best (on a day without wind).