100-400 L: sharpness, tripod and IS

[lordjim]

Hi everyone -

I just bought a 100-400 F4-5.6 L (a long dream that became true) and I am trying to get the best out of it (especially at 400mm).

I took some pics of a heron with a tripod and the results are not crystal sharp :sad: (1/400 sec, F6.3 or 7.1, Iso 100). I did not switch the IS off. Could that be due to the IS? Was the shutter speed too slow (1/400 sec with a tripod!)? As far as I could tell the heron was not moving.

http://www.pbase.com/lordjim/image/44403275

http://www.pbase.com/lordjim/image/44403274

Please note that the above are the results after sharpening using Elements 2.0.

Thank you in advance for your help.

[loebas]

Hi everyone -

I just bought a 100-400 F4-5.6 L (a long dream that became true) and I am trying to get the best out of it (especially at 400mm).

I took some pics of a heron with a tripod and the results are not crystal sharp :sad: (1/400 sec, F6.3 or 7.1, Iso 100). I did not switch the IS off. Could that be due to the IS? Was the shutter speed too slow (1/400 sec with a tripod!)? As far as I could tell the heron was not moving.

http://www.pbase.com/lordjim/image/44403275

http://www.pbase.com/lordjim/image/44403274

Please note that the above are the results after sharpening using Elements 2.0.

Thank you in advance for your help.

I think you are too critical. I like you photo's. But if you use a tripod on a not moving bird ???? I propose working with a AV of 8 plus.

In this threadlink posted by me you see some handheld results of this lens at much worser light and dito high iso and low shutterspeed and wide open AV

http://photography-on-the.net/forum/showthread.php?t=75050

[Tom W]

Not all Canon IS lenses can be used on a tripod with the IS left on. I believe that the 100-400 is one of those lenses where the IS should be turned off when using a tripod.

[lordjim]

Loebas -

Thank you for your answer. The tripod was to prevent my move (and to hold the lens which is not light) and not to compensate for the bird's move.

I will try to stop down further.

No offense but I do not find your pics crystal sharp either but it seems that you were working in difficult light conditions. I was not. Maybe, I am too demanding but I was expecting more from a CAD1900 lens.

That being said, it generally takes me some times to get use to a new lens.

[Tom W]

Just looked at the images, and I like them. The first one is a bit soft, but hard to tell on the second one. How steady is the camera & lens on the tripod? Is there any vibration that you can see in the viewfinder after you bump it a bit? If so, you may want to employ morror lockup to reduct the vibration that is induced by the mirror slapping the roof of the mirror box. I know that the general school of thought is that mirror slap isn't an issue at such high shutter speeds, but I've seen a difference on long lenses, even at 1/400 shutter speeds.

[Coderunner]

I've found that my bestv results are F8 and 380mm. 400mm seems slightly soft all else being equal

[loebas]

Loebas -

Thank you for your answer. The tripod was to prevent my move (and to hold the lens which is not light) and not to compensate for the bird's move.

I will try to stop down further.

No offense but I do not find your pics crystal sharp either but it seems that you were working in difficult light conditions. I was not. Maybe, I am too demanding but I was expecting more from a CAD1900 lens.

That being said, it generally takes me some times to get use to a new lens.

As I want to learn I don't feel offended by you remarks at all.

There is a rule that says to use a TV that is at least the same as your focal lenght
Keeping that in mind and than look at the settings of the photos i took handheld when kneeled down in dark wood, I think they are quite ok.
In good lightning conditions this lens must be a great performer. Wish I could afford this lens

[neil_r]

All instructions specifically state that the IS must be turned off with this lens when tripod mounted.

N

[lordjim]

Tom: Thank you. No problem with the tripod, it works great with the lens, no vibrations. I will try the mirror lock up tip. I will also try to use the remote for the next shots.

Coderunner: I will try at 380mm F8 but I believe the lens should still be pretty good at 400mm. I am not expecting it to be perfect (I would have chosen a prime) but I am confident that it should give me something better. I had some pretty good results in terms of sharpness at 350mm.

Neil: You are right. Thank you. The IS should be off on a tripod with this lens. I do not know why but I was under the impression that it had the new IS mechanism. :o It does not.

By making all the above changes, I should be able to get some significant improvements. :cool:

Loebas: You are right there is a rule that shutter speed should be 1/focal length to ensure sharpness with a telephoto. Well, it is more a tip than a rule (it depends on the light conditions and on the experience of the photograph). Besides, it applies to non IS lenses handheld. You should be able to get a lower speed than 1/focal length with the IS mechanism. However, this tip does not apply if you use a good tripod as the shutter speed can then go down to several seconds (assuming the subject does not move and the light is very low if not you end up with a blur, an overexposition or both (been there :lol:! )).

Thank you guys.

[CyberDyneSystems]

That "rule of thumb" aplies to hand held... no IS, no tri[pod,.. so it's out the window in this case.