Following on from Ann's comparison of the 100-400/4L and 300/2.8L lenses, I'm posting some of my own. When I first used the 100-400 I confess I was disappointed by its sharpness - it was very versatile, but generated a large number of "almost" shots. I finally realised that the poor results were due to an inappropriate technique: namely, sampling focus from one part of the scene, recomposing and then quickly firing the shutter. I'm convinced that there is some kind of "lag" in the image stabilisation, as the lens is razor sharp when the IS is given time to settle (or turned off with the lens on a tripod or some other kind of support).
Anyway, here are three examples of sharp images, and one which demonstrated the classic "shimmer" which seems to be due to firing the shutter before the IS has settled down. All are 100% crops which have been through the RAW converter and basic sharpening in Photoshop.
The relevant inside leg measurements are:
- Starling: 170mm; 1/250s at f/8; ISO 200; 40D
- Tiger: 330mm; 1/500s at f/8; ISO 400; 5DmkII
- Impala: 400mm; 1/800s at f/8; ISO 250; 40D
- Elephant: 400mm; 1/400s at f/8; ISO 200; 40D
The golden rule seems to be that one needs to slow down when using the 100-400. Treated with respect it is capable of some excellent results.
Thanks Ian - I agree that the 100-400mm gives very varying results - sometimes very sharp and other times disappointingly soft. Your explanation sounds plausible - will try a slower approach or turning off stabilisation when using fast shutter speeds.
ReplyDeleteYes, that would explain some observations on my 100-300 IS [not L :-(]. That lens is also hugely affected by aperture; I think I've only ever had really sharp results at F8 or F11.
ReplyDeleteMartinB