"anti-shake" "vr" etc?

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oldson

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simon
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simple question (i hope)
do these features degrade picture quality, in any way?

if not, why is feature selectable, rather than always "on"?

lastly is the "in lens" version, better or worse than "in body"?

thanks for your views, in advance.
 
The 'in lens' version is supposed to be better........ :popcorn:

And it's turn off and on-able because you wouldn't want to use it with a tripod. It can actually cause camera shake, so I'm given to believe!
 
andy_fozzy said:
The 'in lens' version is supposed to be better........ :popcorn:

And it's turn off and on-able because you wouldn't want to use it with a tripod. It can actually cause camera shake, so I'm given to believe!
Click to expand...

cheers for that. now it makes sense!
only wish i had thought of that (tripod use) before asking.
 
If it was on for every shot it would also drain your battery quicker

In lens stabilisation is better in terms of its more advanced - it has been around much longer and improved with time, now being able to 'add' up to 3 or 4 stops of light (8 to 16 times longer shutter speed can be used and the shake reduced) on some lenses, whereas on camera reduction is reletively new and restriced to only adding 2 stops (4 times as long shutter) of light IIRC
 
Of course it adds an absolute fortune to the price of lenses whereas if you are using inbody IS you can use any lens you like including 20 year old 300/400mm primes which cost peanuts by comparison.

Not saying either is better or worse than the other but there are 2 sides to evey coin (y)
 
Uneducated_Rick said:
If it was on for every shot it would also drain your battery quicker

In lens stabilisation is better in terms of its more advanced - it has been around much longer and improved with time, now being able to 'add' up to 3 or 4 stops of light (8 to 16 times longer shutter speed can be used and the shake reduced) on some lenses, whereas on camera reduction is reletively new and restriced to only adding 2 stops (4 times as long shutter) of light IIRC
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In camera shake reduction can and does work up to 5 stops.
 
Apparently it is possible that VR/IS can reduce picture quality (sharpness) if left on whilst using a tripod..many, if not all, DSLRs automatically turn-off in-body stabilisation during mirror-lock for this very reason

Most manufacturers recommend not to use VR/IS when using a tripod

Simon
 
I leave the IS on, whenever I'm not using a tripod on both the kit and the 55-250 lenses. Wouldn't be without it. I've shot at 1/30 @250mm handheld with it. If you leave IS on when the camera is tripod mounted the IS kicks in and the moving lens element will muck up the picture. I've been trying to find an example, but I can't I'm afraid, I've only had it show up in longer exposures though...
 
jgs001 said:
....If you leave IS on when the camera is tripod mounted the IS kicks in and the moving lens element will muck up the picture....
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I would say that you're way off the mark with that statement. I would suggest that most users of the long telephotos will leave IS on (and active) for tripod shots. The only prime telephoto where this wouldn't be a good idea is the 300/4 IS which has a slightly different design.

Bob
 
In-lens is better than in-camera because it is optimised for individual lenses (theory). In-lens is better because it also stabilises the viewfinder (fact). This is very noticeable and very useful for framing moving subjects with longer lenses.
 
I cannot get rid of the suspicion in my mind that VR lenses by virtue of having a floating element moveable by electronic triggering cannot deliver the sharpness of a non VR lens with fixed elements, or is it that the VR at lower shutter speeds delivers better sharpness than you would naturally get with non VR at those lower speeds(handheld)?

Sorry if that is confusing! :thinking:

An example is the Nikon 24-120, I have had the VR unit and thought it soft, I currently have the 'Non-VR' and I find it noticeably sharper and this is a lens noted for softness at anywhere near wide open!:shrug:
 
Have a look at the reviews of the canon 70-200 f4L IS and non-IS. The IS version is sharper, competing with primes pretty much. The only downside is the £££.
 
Canon Bob said:
I would say that you're way off the mark with that statement. I would suggest that most users of the long telephotos will leave IS on (and active) for tripod shots. The only prime telephoto where this wouldn't be a good idea is the 300/4 IS which has a slightly different design.

Bob
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Bob, I took some 30 second exposures of satellite trails using the 18-55 kit lens with the IS turned on. The satellite trail should be a solid straight line. With the IS turned on, the line waves back and forwards in the resulting picture, and after a moment of the exposure starting, the noise of the IS becomes very apparent (I actually thought I had a problem with the camera the first time, as I wasn't expecting the IS to kick in with it mounted on the tripod). I will keep trying to find a sample so I can show you what I mean, and a shot with the IS turned off to show what it should look like. I've had this effect with both the 18-55 kit lens and the 55-250.
 
I did a test using in body IS on a tripod (I posted it here but unfortunately I must have deleted the pictures) but I found that, with long exposures, the images were horrendous with the IS switched on.
 
simonkit said:
Apparently it is possible that VR/IS can reduce picture quality (sharpness) if left on whilst using a tripod..many, if not all, DSLRs automatically turn-off in-body stabilisation during mirror-lock for this very reason

Most manufacturers recommend not to use VR/IS when using a tripod

Simon
Click to expand...

You can actually see what happens when used on a tripod.
In live view you can see the image drift as it hunts for stability.
Of course on a long exposure that makes it smear across the sensor.

This seems to be quite random and some times difficult to see.

However I would not like to be without it at my age.
 
The difficulty comparing IS and non-IS versions of the same lens (eg Canon 70-200 2.8 L) is that they are not the same lens and the optical design is completely revised. Canon's own MTF tests of the IS and non-IS versions show the lenses to perform slightly differently, with both versions having a tiny advantage in different areas.

On the other hand, the new Canon kit lens with IS is miles better all round than its predecessor; ditto the 55-250 IS. And both these lenses suggest that IS does not have to add significant cost at all.

Edit: I have IS turned on with my 100-400L (40D) with tripod/monopod and it works well. But it gets the jitters with a 1.4x Kenko extender. Of course, this takes the max aperture beyond f/5.6 which I'm guessing might be part of the problem. Any ideas Bob? :)
 
HoppyUK said:
In-lens is better than in-camera because it is optimised for individual lenses (theory).
Click to expand...
but bodies with in-body IS have data tables for at least the manufacturers' own lenses which does the same thing
In-lens is better because it also stabilises the viewfinder (fact). This is very noticeable and very useful for framing moving subjects with longer lenses.
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& some people find that it makes them ill, similar to motion sickness so you can argue whether this is a pro or a con.

as I said earlier they both have pros & cons.
you can argue back & forth depending upon your own particular needs which is better - the only general truths are that they both work to roughly the same level & having either is better than none at all.

KavKav said:
I cannot get rid of the suspicion in my mind that VR lenses by virtue of having a floating element moveable by electronic triggering cannot deliver the sharpness of a non VR lens with fixed elements,
Click to expand...
they can suffer from parking errors
 
jgs001 said:
... If you leave IS on when the camera is tripod mounted the IS kicks in and the moving lens element will muck up the picture.....
Click to expand...

Canon Bob said:
I would say that you're way off the mark with that statement. I would suggest that most users of the long telephotos will leave IS on (and active) for tripod shots. The only prime telephoto where this wouldn't be a good idea is the 300/4 IS which has a slightly different design.

Bob
Click to expand...

jgs001 said:
Bob, I took some 30 second exposures of satellite trails using the 18-55 kit lens with the IS turned on. The satellite trail should be a solid straight line. With the IS turned on, the line waves back and forwards in the resulting picture, and after a moment of the exposure starting, the noise of the IS becomes very apparent (I actually thought I had a problem with the camera the first time, as I wasn't expecting the IS to kick in with it mounted on the tripod). I will keep trying to find a sample so I can show you what I mean, and a shot with the IS turned off to show what it should look like. I've had this effect with both the 18-55 kit lens and the 55-250.
Click to expand...

There's a big difference leaving IS off for long exposures as opposed to making a sweeping statement that it will "muck up" shots.
Using tripod mounted long telephotos will benefit from leaving the IS on...especially when when using drive mode....when the IS will help to dampen out any shutter/mirror induced vibrations.
Canon's own advice is thus:
....virtually all Canon Image Stabilizer lenses except the now-discontinued original 1995 EF75-300mm IS model have some degree of tripod-sensing. In most cases, what that means is that when the lens senses that it's completely steady, it effectively prevents the IS mechanism from moving. With typical IS lenses like the EF70-200mm f/4L IS USM or EF24-105mm f/4L IS USM, that’s about as far as it goes. In other words, the IS mechanism doesn’t move when the lens is mounted on a tripod, but by the same token, it doesn’t compensate for other sources of vibration such as the slap of the camera’s reflex mirror prior to the beginning of an exposure. As I mentioned in an earlier edition of Tech Tips, I recommend shutting off the IS mechanism when using these lenses on a tripod in order to save battery power, and also to lock and center the IS mechanism.

However, there is a group of high-end Canon lenses that actually does compensate for mirror slap during tripod use. This list currently includes the EF200mm f/2L IS USM, EF300mm f/2.8L IS USM, EF400mm f/2.8L IS USM, EF400mm f/4 DO IS USM, EF500mm f/4L IS USM, EF600mm f/4L IS USM, and EF800mm f/5.6L IS USM. With these lenses, it's usually a good idea to leave IS on for long exposures on a tripod unless you plan on locking the mirror prior to exposure.

Bob
 
Bob, what's your reference for that info? Is it something anyone can subscribe too? Thanks.
 
HoppyUK said:
Bob, what's your reference for that info? Is it something anyone can subscribe too? Thanks.
Click to expand...

Canon's North American Technical Director (Chuck Westfall) runs a technical Q&A session on the Digital Journalist monthly website. Canon users write/email questions and criticisms and these are addressed/answered.
My quote came from the Q&A portion of last July's tome http://digitaljournalist.org/issue0807/tech-tips.html

If you want to read various other questions and comments then check the archive index here http://digitaljournalist.org/archives.html
Select the year and then scroll down to the "tech tips" link that will appear in each of the monthly sections.....there's a lot of useful information to be had.

Bob
 
Sorry Bob, you're right I should have said it was for long exposures in the first place :amstupid: :D
 
Thanks Bob. Chuck Westfall - very interesting and helpful guy :) Looks like some meaty reading ahead! Cheers.
 
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