Does Image Stabilisation adversely effect image sharpness?

[Colin Southern]

Manfred - et al, I just found this -

http://software.canon-europe.com/fil..._Book_9_EN.pdf

I did not know an electronic version was avaialable publically and for free, from Canon.

I still like the hard copy, hard cover book, though.

WW

Hi Bill,

This is an older version - I think I'm up to v9 or v10 for the printed copy (covering lenses like the EF16-35/F2.8L USM II).

[William W]

I'm up to v9 or v10 for the printed copy (covering lenses like the EF16-35/F2.8L USM II).

My Library is overgrown and we just sent TWO car-boot loads of books to the Salvation Army Store . . .
I am on a “space saving” and make the house “neat” ration.
I am not allowed to buy any more: DVD's; Books; or magazines.
I am however still allowed to still buy wine . . . so realistically I think I will stay in charge of the cellar and keep the Boss happy with the bookshelves appearing respectable and no "piles" (of books) on the carpet . . .
So for me - my 2004 hard bound copy is what I have at the moment . . . and I will wait for Canon to release the newer versions in pdf file medium.

I am thankful for small mercies.

Bill

[mykeowens]

Hi Colin,
I have been struggling with IS and panning. You mention "double image" could I ask for your opinion on what I'm seeing please?
Look at the star at the feet of the wingwalker here https://www.dropbox.com/sh/1fspd99en....Y3NWx6Ob.dpuf

Looks like a double image to me!
Best regards
Myke

[Polar01]

I am afraid that Colin is not longer a member here at CIC, also note that the thread is at least 4 years old. May get better response if you started a new thread about your problem. One question I would as is what was your shutter speed and you f-stop when you took this image.

Cheers: Allan

[Manfred M]

Myke - the file metadata says you are shooting a Canon 5D Mk II and a Canon f/2.8 70-200mm ISM + a 1.4x teleconverter. You were shooting at ISO 200 at 1/2000th sec at f/4 and 280mm focal length.

I don't know the Canon lenses, but I have the Nikon equivalent. It has a switch that allows me to change from regular image stabilization to a different mode of stabilization that is used when panning. Does the Canon lens have this feature and if so, were you using it?

In optical stabilization, the camera uses accelerometers to measure lens velocity and acceleration and if move a floating lens element inside the lens to compensate for this motion (i.e. camera shake). If the wrong IS mode was in use of the motion exceeded the camera's ability to compensate, I can definitely understand that you could be seeing a bit of blur. If you look, it's not just the shoe that is a bit blurred, the whole image shows signs of softness when viewed at 100%.

[William W]

. . . the file metadata says you are shooting a Canon 5D Mk II and a Canon f/2.8 70-200mm ISM + a 1.4x teleconverter. You were shooting at ISO 200 at 1/2000th sec at f/4 and 280mm focal length.
I don't know the Canon lenses, but I have the Nikon equivalent. It has a switch that allows me to change from regular image stabilization to a different mode of stabilization that is used when panning. Does the Canon lens have this feature and if so, were you using it?

Hi Manfred - quickly FYI:

There are two EF 70 to 200 F/2.8 L IS Lenses, (the original and the MkII).

Both support “Image Stabilization Mode 1” and “Image stabilization Mode 2” which is selectable by a switch on the lens’s body.

When panning, “Image Stabilization Mode 2” should be selected. It should also be noted that the IS in this case seeks to (only) arrest Camera Movements which are at 90 degrees to the panning action.

Both Lens’s Image Stabilization will function correctly on an EOS 5D MkII when combined with the Extender x1.4EF MkII & MkIII: I am not sure about use with the Extender EF x1.4. (the original).

Canon will make no guarantee about Lens/Camera performance when used with third party Tele Converters (Extenders).

I have not viewed the image, yet – therefore no specific comment thereon.

WW

[Stagecoach]

Looking at the images, it appears the lines running vertical (meaning nearest vertical to the camera position) appear sharper than those in the near horizontal direction.

That is something I have come across when panning race cars.

[William W]

. . . If you look, it's not just the shoe that is a bit blurred, the whole image shows signs of softness when viewed at 100%.

I just performed a cursory forensic interrogation: it’s an interesting technical study.

I think that there are possibly a few things happening which are the causes DIFFERENT Blurs in the image.

Quick Summary –

1. A reasonable assumption is that the two people are the most flexible Subject Areas in the image, they both appear to have Subject Motion Blur – they appears to each be moving backwards and downwards at an angle of about 45 degrees down to camera left. The movement seems to be at a reasonably consistent speed for each of two evidenced by the comparative length of trailing edge blur on the Pilot’s Helmet and the Wing Walker’s Belly Buckle – and assuming that the head of the pilot is slightly more ‘wobbly’.

2. A similar direction of what could also be Subject Motion Blur appears in the Star on the top main wing (as already mentioned) and also the squares of the lower main wing of the Bi-Plane. What is interesting is that the speed of the movement appears more on Starboard Side than the Port Side of the Bi-Plane, which leads one to believe that there is “Banking Downward to Starboard” movement. This seems logical considering the general aspect of the Bi-Plane and assuming the camera Viewpoint was at Ground-Level.

3. What’s also interesting is a not-so-similar Blur in the Tailplane area (almost an Horizontal Leading Edge Blur). This blur would be consistent as a result of using the IS in Mode 1 (and not Mode 2) whilst performing an Horizontal Pan.

To more precisely interrogate the image’s blurs, one requires the typical air speed; the propeller dimension; the wing span and typical RPM of the prop.. And we’d assume that the image is a full frame crop. But I think that’s probably a bit academic, though possibly an interesting puzzle.

***

In summary two points:


IS MODE:
1. What we really need to know is if Myke had Mode 2 IS engaged (or not) and that will answer a few questions about the Tailplane Area (and the Engine Area appears similar). I’ll go out on a wing and offer a guess is that he didn’t and these Tailplane blurs are as Colin described in Post#6 of this conversation.

(Gee that was dangerous to make a guess). But if Myke did engage IS Mode 2, then the answer to the tailplane and the engine blurs is possibly that the plane is more flexible – front to back - than I assume.

SHUTTER SPEED:
2. The other answer is, prima facie, the Shutter Speed was not fast enough to arrest the Subject Motion Blur of all the directions/speeds of motion for the Aircraft’s general Flight Speed and especially the Banking Manoeuvre , (certainly not when interrogating the image at 100% and closer).

This is the more significant finding.

WW

PS: I’d appreciate Myke confirming what x1.4 Extender was used.

[William W]

Myke?

[jimioutback]

I noticed while pixel peeping that my Sigma 24-105 was less critically sharp with IS on so I stopped using it. I hadn't thought that it might be related to shutter speed and IS operational frequencies. The IS wasn't very effective anyway so no big loss.

[jimioutback]

I think it's more "in theory" than in practice.

Why not do some tests and let us know what you discover?

Keeping in mind too, that the one over focal length rule for hand holding is only a rule of thumb for MINIMISING camera shake, not eliminating it -- so IS/VR may well still contribute something useful well above those speeds.

Without any such suspicion I did notice while pixel peeping that my Sigma 24-105 was less critically sharp with IS on so I stopped using it. I hadn't thought that it might be related to shutter speed and IS operational frequencies, but it definitely made a detrimental difference at 100%. The IS wasn't very effective anyway so no big loss!

[Black Pearl]

Without any such suspicion I did notice while pixel peeping that my Sigma 24-105 was less critically sharp with IS on so I stopped using it. I hadn't thought that it might be related to shutter speed and IS operational frequencies, but it definitely made a detrimental difference at 100%. The IS wasn't very effective anyway so no big loss!

This is an ancient post - why not start a new one and including the 100% enlargement examples showing your findings?