Pete, the bucket size is the number of pixels each thread of the processor works on at one time. You should adjust the bucket size to something more realistic: a bucket size of 1 is useless, the smallest I use regularly is 16 (i.e. 16 x 16 pixels) and anything larger than 128 makes little sense.

Choose 32 as a start point.  I've rendered complex scenes at well over 6000px in Poser 8 with no trouble, though it does take a while. 

What are your system specs? (Just CPU, RAM and OS).

Which software version?

What render settings (a screenshot is best)?

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Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)

PoserPro 11 - Units: Metres

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