7D Mark II

[Fay]

After a long wait my brother and I got our hands on a couple of Mark IIs. Problem is after a week of work we still feel like pictures are soft. I originally started trying to adjust with some of the methods on the web. I finally said @#$ with that and bought a LensAlign MKII and then the Focus Tune V3. Over the weekend we got the system set up and learned the basics of the software. Adjustments were made after doing 5 shots in steps of five. Then when we had the general area we shot 10 images in steps of 1 around the indicated best spot. Several times we did an even tighter refinement again using 10 shots for the software to scan. This was done with the 100-400 at both ends of the zoom and the 600 with and without the 1.4 extender. I think I got the 100-400 zeroed in, but brother is still frustrated. Neither of us like the results with the 600 after micro adjustments.

One thing we did notice is that when the lens was locked down on the tripod and we pushed the TC-80N3 remote controller button half way the focus point tended to drift down. The image stablization was on with all lens. I usually don't tripod my 100-400 and when using the 600 the tripod is typically not locked down so I was told the IS being on was okay.

So any suggestions or words of wisdom would be appreciated. To be truthful I am a very short way from taking the camera back and replacing it with a different body.

Thank you. Fay and Robert

[cicopo]

IS should be OFF. That drift downward was the IS kicking in. How stable is the tripod? When I'm doing serious tests I mount to something that can't move like the one in the 2nd message here.

. http://www.fredmiranda.com/forum/topic/1330556/3

Or something like this

[Fay]

Thanks cicopo I was afraid that may be the answer. All I can say is @#$%#$ and go back and do it all over again. What a frustration.

The cameras are on heavy duty fiber carbon tripods with a Whimbery head. Fay

[KeithR]

The more stable the platform, the more likely you'll get problems from image stabilisation that isn't explicitly designed to work with a tripod.

[RobertTheFat]

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@KeithR wrote:

The more stable the platform, the more likely you'll get problems from image stabilisation that isn't explicitly designed to work with a tripod.

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I know that's the conventional wisdom, but I wish someone would explain why it's true. What's the difference between mounting the camera on a tripod and holding it absolutely still? The latter doesn't represent a challenge to the IS system, does it? And if the tripod is buffeted by a breeze, why isn't that like holding the camera not quite steady, in which case the IS would presumably help?

[ebiggs1]

The IS operates by correcting shake and when there is no shake, or even when the shake is below the threshold of it's detection capability, the IS feature can actually add unwanted blur to the picture.

 IS lenses look for vibrations in your camera in order and try to reduce it.  When IS doesn't find any as you use a tripod, for instance, it can actually cause it.

You know ying and yang working against each other.

[ebiggs1]

Oh, BTW, if you look carefully sometimes you can see the image jump when it is on a tripod.

Turn it off.  

[Skirball]

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@ebiggs1 wrote:

The IS operates by correcting shake and when there is no shake, or even when the shake is below the threshold of it's detection capability, the IS feature can actually add unwanted blur to the picture.

 IS lenses look for vibrations in your camera in order and try to reduce it.  When IS doesn't find any as you use a tripod, for instance, it can actually cause it.

You know ying and yang working against each other.

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Do you have anything to support this?  Other than ying and yang.  I've heard this story many times, but haven't seen an explanation more details than this.  It may well be true, but it just doesn't make any sense to me.  It would be an extremely poorly designed system if it couldn't detect that it wasn't moving.

[KeithR]

Isn't it safe to assume that there's a reason why Canon explicitly recommends turning off IS on tripods; and that there's a reason why it has actually developed tripod-sensing IS on some of the big Whites?

But here's some reading on the subject from Canon - hopefully authorative enough (and ten seconds' work in Google to find):

http://cpn.canon-europe.com/content/education/technical/image_stabilization_lenses.do

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When using certain early models of IS lenses with a tripod it was necessary to turn off the IS function. This is because of a phenomenon known as ‘Shake Return’. Shake Return occurs when the IS system tries to correct vibrations to which the system itself contributes. When the IS lens sits on a tripod, the IS detection gyros pick up any tiny vibrations or movement; these might be caused by the tripod being knocked, or the photographer adjusting a camera setting.

The IS system then swings into action to correct that movement. The movement of the IS lens group causes its own minute vibration, which is in turn detected by the movement sensor, which triggers another correction. This ‘feedback loop’ can continue endlessly, resulting in the addition of unwanted blur to images that would be sharper if the IS function was switched off.

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[Skirball]

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@KeithR wrote:

Isn't it safe to assume that there's a reason why Canon explicitly recommends turning off IS on tripods; and that there's a reason why it has actually developed tripod-sensing IS on some of the big Whites?

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Actually, no.  Look through your owners manual, you'll see all kinds of things contraindicated that most of us do every day with our cameras.  It's the nature of literature in a litigious world.

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@KeithR wrote:

But here's some reading on the subject from Canon - hopefully authorative enough (and ten seconds' work in Google to find):

http://cpn.canon-europe.com/content/education/technical/image_stabilization_lenses.do

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When using certain early models of IS lenses with a tripod it was necessary to turn off the IS function. This is because of a phenomenon known as ‘Shake Return’. Shake Return occurs when the IS system tries to correct vibrations to which the system itself contributes. When the IS lens sits on a tripod, the IS detection gyros pick up any tiny vibrations or movement; these might be caused by the tripod being knocked, or the photographer adjusting a camera setting.

The IS system then swings into action to correct that movement. The movement of the IS lens group causes its own minute vibration, which is in turn detected by the movement sensor, which triggers another correction. This ‘feedback loop’ can continue endlessly, resulting in the addition of unwanted blur to images that would be sharper if the IS function was switched off.

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Thanks, sarcasm aside.  That's interesting.  I trust that the Canon engineers are better engineers than I.  But I'm surprised that something that seems like simple feedback isn't avoidable.