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New holland honeyeater crop only |
This is an update on my previous post on this subject whichyou can read here.
I have been running many tests on static and moving subjects of different types.
The tentative position I have arrived at is
For static subjects
The 1.4x extender delivers slightly better rendition of fine detail and slightly less luminance noise (grain).
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With 1.4x extender |
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Crop only |
For moving subjects
The lens without extender appears to have
* more reliable focus with fewer misses
* better tracking with a higher keeper rate.
* slightly better stabiliser function.
I say “appears to” here because it is difficult to set up exactly comparable moving subject conditions.
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Whip bird with extender |
At all times
Using the lens without the extender is more user friendly than with it. The kit is easier to carry in a compact package. There is no need to manipulate the lens, body, extender and various caps to get the extender mounted.
Without the extender the full focal length range of the lens is available.
Notes on sharpness vs focal length range
The extender prevents operation between 100-420mm.
From 420mm to 500mm I would expect the bare lens to be better.
The advantage for the extender would be confined to the range 500-700mm or 600-800mm. Somewhere in that range anyway.
Conclusion
There does appear to be an advantage to the extender for ultimate rendition of fine detail in static subjects in the 500-700mm range.
However for bird/wildlife/sport/action work the flexibility, versatility and slightly better focus, tracking and stabiliser functions without the extender could make a good case for leaving the extender at home.
It only takes the slightest touch of off-focus, or a small amount of camera or subject movement to negate the advantage of the extender.