Dear CANON EF100-400 user, I would need your opinion

[JetSpotter215]

I have just bought a Canon EF 100-400 lens and I would like to hear your opinion about the attached test photos because the image quality (sharpness) scatters between different examples and I really have expected more sharpness of this lens.

Attached I have two pictures, shot at 100 and 400mm. One the left side you will see a 100% crop at maximum aparture of the lens and on the right side is a crop at minus one f-stop.
@100mm

@400mm


Do you think this is a poor, average or a normal example of the EF100-400 lens, concerning sharpness?

Thanks in advance for your replies!

[Iwan Bogels]

Hi JetSpotter,

Am I right that you shot all images at about 0,3 or 0,5 second exposure time ? If so, would you mind doing the same test in brighter light with 1/1000 exposure to rule out all the possible motion problems ? So far I would not be unhappy with the result, if I were you.

Oh, and max aperture at 100mm is lower than at 400mm. So you may want to use max aperture and f8.0 to compare.

Cheers,
Iwan

[JetSpotter215]

Dear Iwan,

Thanks for your reply.

Some words to the making of my test photos. Camera+lens were fixed and I used a remote control for shooting, so no influence from any motions.
I also made some test photos at f8.0 (not available now), where sharpness was really ok.
But isn't the exposure time to slow for action photos at such aparture times, if you would not increase ISO?

Which settings of exposure time/aparture value you normally use for action photos?

Regards,
Christian

[Iwan Bogels]

Hi Christian,

The general rule for shutterspeed is to use at least the same shutterspeed as the focal length. This means:

1/100 sec shutterspeed for a 100mm lens
1/250 sec shutterspeed for a 250mm lens
1/400 sec shutterspeed for a 400mm lens

These are all minimum shutterspeeds. In Europe it's not uncommon to find the correct camera setting at ISO 100 - 1/500 sec - f5.6. But with todays sensors it should be absolutely no problem to increase ISO to 200 or even 400. This would allow you to use f8 most of the time. I know that with the EOS 400D you may want to avoid ISO 400, but ISO 200 should be no problem at all.

Regarding my own settings for action photography, it depends on the situation. Sometimes I drop the shutterspeed to 1/125 or even 1/60 at my 300mm when I try to achieve background-, propellor- or rotorblur. But when intentional blur is not an issue, I do tend to use 1/1000 or higher for shutterspeed. For me apperture is not as much an issue as shutterspeed is. After all, unsharpness caused by camera motion is a bigger problem than unsharpness caused by lack of depth of field. And as I use a camera with a 1.3 crop factor, I don't have to worry too much about vignetting as dark(er) corners stay outside sensor view. Your situation with the 1.6 cropfactor is even better.

But when you have to shoot near apperture minimum (f5.6 with your lens), apperture will become more of an issue than with my lenses (most are f2.. So you will have to make your own decision on which settings to choose. There are many factors to consider.

Hope this helps.

Cheers,
Iwan

[MikeLima]

I use the Canon 100-400mm L f/4.5-5.6 with a Canon 50D. Standard setting is f/8.0 (sometimes f/7.1 also) with ISO values ranging between 125 and 400. Shutterspeeds vary with these settings from 1/320th to 1/3000th, depending on conditions.

These settings work fine for me, on each focal length of the lens.

My personal experience is though, that you have to stay away from the maximum apertures of this lens (f4.5-5.6), to avoid a dramatic loss of sharpness.

[JetSpotter215]

Dear Iwan, Dear MikeLima,

Thank you for your very helpfull answers.

Best Regards and good light
Christian