What am I doing wrong?

Hi all,

I was considering selling my Sigma 150-500mm and getting the Canon 100-400, but then I saw this thread and it occurred to me that its probably me.

Here is a gallery of my images, but I'll put these two Sigma shots forward for comparison.

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5204​015481/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5204​221091/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5623​486425/

I have no idea what you want help with. Can you elaborate? These two images are taken in such different light that there isnt much to compare.

I too am really confused. What exactly do you need help with?

Well, I picked the best of all my shots with the 150-500 which is fine, but I take just two shots with the 100-400 on a overcast day and get decent IQ and sharp focus, let me see if I can get a closer example.

I have edited the original post and added two from the Sigma pics to better shot the issue, to me the Sigma images look soft and a little flat.

I'm not seeing what's wrong with those, but I do notice, in your 2nd and 3rd, that your shutter speeds are a bit slow for the focal length you're shooting at. Remember that your minimum shutter speed should be 1/focal length including the crop factor. So, in your 2nd pic, you shot it at 340mm but remember the crop on your 7D is 1.6 so it's really 544, so your minimum shutter speed should have been at slowest 1/544 sec. (not counting any IS systems, obviously)

John_N wrote in post #12235000
Well, I picked the best of all my shots with the 150-500 which is fine, but I take just two shots with the 100-400 on a overcast day and get decent IQ and sharp focus, let me see if I can get a closer example.

I have edited the original post and added two from the Sigma pics to better shot the issue, to me the Sigma images look soft and a little flat.

Overcast light is wonderful for revealing detail that would be obscured in shadow or lost to the contrast of hard daylight. It might have nothing to do with gear, and more to do with the quality of light you have been shooting in.

Ah, thank you - as you've got me looking at the details yes on the 100-400 I was a little under speed, but not by much, also the ISO was higher hence a brighter shot (I think).

I'm just looking at my original of the guy on the beach, how can I tell for sure that its camera shake.

I'm not really sure how to do a 100% crop shot in lightroom, but here is a close up roughly close to the zoom.

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5624​990177/

gonzogolf wrote in post #12235071
Overcast light is wonderful for revealing detail that would be obscured in shadow or lost to the contrast of hard daylight. It might have nothing to do with gear, and more to do with the quality of light you have been shooting in.

Aye, but on the whole the images from the Sigma just don;t match up - that said I may have just taken the best shot that I will ever with the Canon just by pure luck

John_N wrote in post #12235108
Ah, thank you - as you've got me looking at the details yes on the 100-400 I was a little under speed, but not by much, also the ISO was higher hence a brighter shot (I think).

I'm just looking at my original of the guy on the beach, how can I tell for sure that its camera shake.

I'm not really sure how to do a 100% crop shot in lightroom, but here is a close up roughly close to the zoom.

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5624​990177/

Looks like some movement to me.

For shots without IS using the 7D your minimum shutter speed should be 1/focal length x1.6 In your blown up shot you are at 1/320 for a 340mm shot. Your safe handheld speed ought to be 1/450

Thank you all, I'll take a look at both my other images and those taken by others and I think I'll see what you guys are telling me.

I'll also try and get out tomorrow with the Sigma and give it another bash - I'll probably cheat, stick it on TV, set it to 1000 and click away

Motion blur and focus blur look distinctly different, in that motion blur seems to be moving in a direction whereas motion blur is more omnidirectional. In your blown up guy's face crop, it looks like the camera was moving frame-left-to-right as the blur has that directionality to it. It also looks pretty noisy for iso 400...

Well, as promised I've taken your collective advice and sped things up a bit, as I recall someone saying its harper at f8 I set it to manual to lock speed and apature - I left the ISO on auto though.

Anyway heres a sample:

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​234361/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​267167/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​842736/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​879046/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​821878/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​299547/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​326291/

IMAGE LINK: http://www.flickr.com/​photos/magsnorton/5627​930664/

The only problem I have left I guess is pinning down if my micro adjustment should be +2 or +3, I can;t quite make my mind up!

If I recall correctly the first image (upper left) and the cross were on +2, some on +3 (including the running dog) then I eventually switched back to +2 - I wish there were a way to tell in the metadata

Very difficult to tell anything from all your photos because they are rather small and have varying subject matter and lighting conditions.

His 150-500 does have OS so no need for 1/1.6x focal length for handheld photos if OS was turned on. There might be a front focusing issue with the lens especially if the last photo was focused on the girl's face and not her hands. I suggest the OP look at doing micro autofocus adjustments to tune in his lens.

I have the Bigma (Sigma 50-500) and it is a lens that is known not to be that sharp wide open needing f/8 for good sharpness. f/8 doesn't yield as nice of backgrounds as using the Canon 100-400 at f/5.6 but Sigma's 50/150-500 lenses are known as being good value lenses for $1000. If you want something better pay more for the Canon 100-400.