In only has 5 diaphragm blades and on some shots the bokeh was unpleasing.I used it @400mm in 99% of the time so the push pull zoom ended up beeing more of an inconvenience for me.Even with IS turned on I still found it hard to get tack sharp shots handheld at 400mm so I ended up using a beanbag, monopod or tripod most of the time.Don't get me wrong, the 100-400 is a great lens. I would probably still own and use it happily I someone wouldn't have stolen it from me. But next time I'd probably buy the 400/5.6 prime.But it all depends on what you intend to use it for.

I don't have problems with the Bigma I have an old non DG version but always use it with a monopod or bush hawk and provided my technique is ok I get sharp pictures.once mounted on a monopod I find it quite comfortable to carry the Bigma over my shoulder.

yeah bob, that rabbit shot is sweet.

Nice shots Bob. That rabbit shot makes me think of watership down;) Does the lens work well with a 1.4xTC? Cheers Mike

Yes, f6.3 and f5.6 are almost the same. IS makes the difference.Shooting in open light can make IS unused, but it you deep into a forest and hunt for a birds/squirrels in shadows you will have 1/200sec for ISO800 and here IS helps a lot.

Mike Fursovwrote:Yes, f6.3 and f5.6 are almost the same. IS makes the difference.Shooting in open light can make IS unused, but it you deep into a forest and hunt for a birds/squirrels in shadows you will have 1/200sec for ISO800 and here IS helps a lot.Here are some samples, "small forest" and some squirrels, at sunset, all ISO-400: 1/125, f/8:1/160, f/8:1/250, f/6.3:1/320, f/6.3:1/320, f/6.3:All the above are straight out from the camera, resized in DPP. The following one was shot at 1/80, f/6.3, spent two hours on post processing, here is the workflow: http://www.photo96.com/blog/?p=224ISO-100, f/6.3, 1/125, also spent few hours on post processing: http://www.photo96.com/blog/?p=50I think IS is optional, monopod is a must. -- Yongbo Photo Gallery:http://www.photo96.com/

Hi Mikethe 1.4 converter works better as far as focus is concerned on my 400D in good light with the pins taped but my 350D does not like the 1.4x and hunts for focus as can be expected the IQ does drop with converter attached so have a tendency not to use it unless I have no choice. thanks guys for the commentscheers Bob

Nice samples! I was really confused to see sharp photos with the shutter you used for 400-500mm range from non-IS lens.Only in the end of the message I've read that you used monopodI use the same shutter speeds with 100-400L (1/200-1/300 for 400mm) and have never thought about monopod. This is the difference.

BTW I do really think that SIGMA 50-500 will be a better option than Canon 100-400 in 3-4 years when we will have usable and noiseless crop from ISO3200.

Mike Fursovwrote:BTW I do really think that SIGMA 50-500 will be a better option than Canon 100-400 in 3-4 years when we will have usable and noiseless crop from ISO3200.That's a very good point. Hopeful, my 40D will arrive this month, so I can try ISO-800 and above. The ISO-800 on 300D is useless. BTW, I checked your gallery on pbase, those pictures from the kit lens are very nice, that proves the post processing skill is a big factor in digital photography. -- Yongbo Photo Gallery:http://www.photo96.com/

I've been looking into both these lensesand after seeing some of the cropping done using the 50-500 compared to even a 300mm f4 i have say i dont think the bigma is the oneBut what about the 80-400mm which does have OS on it as welland is nearly 600 dollars cheaper than the canonhttp://www.adencamera.com/prod-overview.asp?ProdID=1350&Category=7

I had the sigma 80-400 and now use the canon 100-400. For what its worth I wouldnt trade the canon for the sigma if I was given $1600 to boot. Just my take.My beefs with the sigma were: slow focusing issues, OS issues, IQ not to mention the added wight and bulk -- http://www.pbase.com/salmo_salar