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Old Mar 15, 2008, 7:19 AM   #11
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NHL wrote:
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This is odd since when VR or IS help in action or sport?
Don't you need a higher shutter speed to freeze the action... and with a higher shutter speed don't you stop the camera shake as well?


In "panning" one actually turns the IS(VR) OFF in one axis ...
I don't necessarily agree.

Case in point:



I'm sure we all agree that image stabilization would certainly have prevented any vertical camera shake from inducing motion blur, but I submit that image stabilization can also prevent motion blur from minute variations in the rate of panning.

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Old Mar 15, 2008, 9:51 AM   #12
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DarkDTSHD wrote:
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Thanks man. Hmmm....I had previously believed in VR any how...still,the Sigma 70-200 w/o OShas been proven to be sharper (less vignetting, less CA...etc.) when stopped down to at least f/4 than the Nikkor equivalent. ...
That doesn't have anything to do with whether the lens contains IS or not, and is true of almost all lenses. It is a rare and expensive lens that is as sharp wide open as it is stopped down.
Regarding whther having IS does or does not have a big influence on the MTF I suppose is open to debate. NHL posted two links for two versions of a Canon lens. The non IS version has better MTF.

Nikon's 70-200 f/2.8 VR vs Sigma's 70-200 f/2.8...Sigma's is sharper stopped down to f/4 (according to http://www.slrgear.com test of the Sigma). Does it have anything to do with not having OS? Shrug. Could be Sigma's combination/type of lens elements.

I guess most will agree though that it is better to have IS/VR than not. Even if it's not a foolproof tool and that shooting style and "technique" play a very important part in getting a sharper image So if we're talking about considering the Nikon VR 70-200 and the Sigma non-OS I suppose one would have to weigh in factors like how much low light shooting you plan to do hand-held. Whether you're willing to carry around a tripod for your night shots of still objects. And your budget. Can you afford to spend the extra $700 for a VR lens.
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Old Mar 15, 2008, 10:27 AM   #13
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Mike Johnston's Catch the Rave! is an article is about the Konica Minolta 7D that talks about the benfits of stabilization with this camera model. But, some of Mike Johnston's impressions would also apply to other systems with Stablization (lens or camera based).

Here's a quote from it that I found impressionable, as I think about the photos I've missed in the past when I've had shutter speeds a bit too slow to prevent blur from camera shake.

From a Sunday Morning Photographer Series Article by Mike Johnston. See Catch the Rave! for the entire article:

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What pleases and amazes me most about the 7D is when I think back in my mind to the thousands upon thousands of pictures I've taken in my life using too wide an aperture, or too fast a film, or struggling with camera-holding techniques, making attempt after attempt to steal a clean shot in low light. And also, of course, thinking of all the shots that got away because of camera movement. The more such examples you can recall in your own experience, the more you will love the Konica-Minolta 7D. Personally, it has convinced me that spending any less for a DSLR would have been a golden opportunity tragically missed.
Here's another of Mike's articles that touches on the benefits of stablization:

A Tale Told by Two Pictures


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Old Mar 15, 2008, 10:41 AM   #14
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Rjseeney has said it best.

Also agree with NHL (see, we can agree sometimes :G) - any time you introduce more complexity or moving parts or elements in a lens you risk introducing more potential problems. But it isn't a blanket statement you always need to compare a lens on a case by case basis.
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I guess most will agree though that it is better to have IS/VR than not. Even if it's not a foolproof tool and that shooting style and "technique" play a very important part in getting a sharper image So if we're talking about considering the Nikon VR 70-200 and the Sigma non-OS I suppose one would have to weigh in factors like how much low light shooting you plan to do hand-held. Whether you're willing to carry around a tripod for your night shots of still objects. And your budget. Can you afford to spend the extra $700 for a VR lens.
Here's my take on the above:

1. IS vs. Non-IS: To me it's a matter of how best to spend limited finances. with unlimited budget. sure it's better to have IS vs not having it. But, you also have to consider how else could you spend that $700 and could that investment better help your photography. For instance I recently bought canon 70-200 2.8 to replace my sigma 70-200 2.8. I chose not to buy the IS version. Instead that $500 went to a canon 580exII flash and external battery pack. All of which were infinitely more useful for a recent wedding shoot than IS would have been. And they'll be of great help when football season rolls around. Again much more so than IS would have been. Thats not saying IS might not prove useful to me - just not as useful as these other tools. Others are different and IS might be more useful than different allocation of funds.

2. night shots - here's a thing I've noticed about a lot of photos relying on IS - they're bad. Some are good to be sure. However some people try to stretch it too far or their subject is moving slightly. So they misuse the tool. Be careful of that. IS CAN be very useful in situations like this as long as you understand it's limitations.

3. Comparing Nikon VR to the Sigma. I can't speak for Nikon. But I recently sold off my sigma lens in favor of canon 70-200 2.8. The canon performs better at 200mm and it's definitely faster to focus in low light. In good light my sigma did very well but in low light there's no contest. Mark1616 also upgraded recently to the canon with IS. His Sigma had more problems than mine did so for him it was an even bigger improvement. Bottom line here - MTF charts are not the end all and be all of determining quality. They're only one indicator. Now I can't say that the increase from sigma to nikon would be the same - only that it's a possibility. I've always said my sigma could do the job about 90% as well as the canon could - I still think that's true - but that 10% was becoming important to me - as low light sports are all about that 10%. I've also been concerned that there seem to be more complaints about the newer sigma 70-200 2.8 lenses (dg and dg macro). The older non-DG lenses like I had or NHL has seemed to have less issues. Maybe the new version II of the lens will correct those problems.

In the end I would say my opinion of IS is this:

It can turn photos from a very good photographer into better photos. But photos from a good or so-so photographer will still be just good or so-so and most of those good or so-so photographers could probably benefit more from using the right tool for the job (i.e. not trying to rely on 4 stops of anti-shake) and using faster lens, flash, higher ISO or some stabilizing platform (tripod, monopod, ground, wall, etc). And without a doubt most could benefit from learning and practicing proper hand-holding techniques. Unfortunately too often they rely on IS as a crutch rather than doing the above and the results show it.





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Old Mar 15, 2008, 10:50 AM   #15
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JimC wrote:
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Mike Johnston's Catch the Rave! is an article is about the Konica Minolta 7D that talks about the benfits of stabilization with this camera model. But, some of Mike Johnston's impressions would also apply to other systems with Stablization (lens or camera based).

Here's a quote from it that I found impressionable, as I think about the photos I've missed in the past when I've had shutter speeds a bit too slow to prevent blur from camera shake.

From a Sunday Morning Photographer Series Article by Mike Johnston. See Catch the Rave! for the entire article:

Quote:
What pleases and amazes me most about the 7D is when I think back in my mind to the thousands upon thousands of pictures I've taken in my life using too wide an aperture, or too fast a film, or struggling with camera-holding techniques, making attempt after attempt to steal a clean shot in low light. And also, of course, thinking of all the shots that got away because of camera movement. The more such examples you can recall in your own experience, the more you will love the Konica-Minolta 7D. Personally, it has convinced me that spending any less for a DSLR would have been a golden opportunity tragically missed.
Here's another of Mike's articles that touches on the benefits of stablization:

A Tale Told by Two Pictures

Thanks for the link JimC. Good read!

Looks like I'm going to foot the extra $700 for the Nikkor VR 70-200. Even if the Sigma was said to be sharper when stopped down to f/4 (less vignetting, less CA...etc.). Better to have VR than not.

And thank you ever one else for chiming in as well!!

Now onto other things....later guys.
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Old Mar 16, 2008, 8:02 AM   #16
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DarkDTSHD wrote:
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Better to have VR than not.
Not necessarily and here's why:

VR works best in low-light and still, but guess what? Low-light usually means poor lighting and photography is all about lighting! Here's an example taken with a 500 f/4 IS to illustrate JohnG point:




-> This shot was captured @ 1/250s with a 500mm (with IS OFF) and I'll go into that in a few moments...
This should be an ideal shot for IS (or VR): long tele photo and handheld under the cover of trees, but guess what?

1. If VR is used here this picture would have been totally unacceptable as only a silhouette of the subject would come out. Why? when you shoot under tree canopy the camera is ususally pointing up to the bright sky behind the leaves (which thoses bright spots in the background are...)

2. In poor lighting regardless of how sharp the lens is, the picture still have the appearance of poor focus because of the lack of contrast and saturation... and I can point you to many posts of folks having poor results wide open with top-end lenses.

3. As JohnG points out a flash here makes a whole world of difference, and takes away the need for VR (or IS), as a flash pulse is so fast that it would freeze any image... I also need 1/250s because this is the shutter limit where the flash can output its maximum power to overcome the strong backlit
-> The benefit here is dual-fold as it also returns the color saturation and contrast that no IS or VR could ever done if you were to depend on it!

4. Now you're also comparing the 70-200 VR to the Sigma 100-300 f/4 EX - All you need to do is to go back to the various lens threads and see how many folks already are asking about 1.4x or 2x teleconverters, because once you start exploring this option that means you don't have enouch reach. As good as the 70-200 VR is by itself theses are just facts:
a) No 70-200 with a 1.4x TC can equal the Sigma 100-300 as this lens is as sharp as a prime.
b) By the time you use a 2x on the 70-200VR its AF speed is so degraded that a 100-300 with a 1.4x TC looks much more promising...

I have many lenses with IS, but I don't buy a lens because it's better to have VR: :blah:
i.e. I could have bought an EF 70-200 f/2.8 IS too; However, I rather spend that $ on a 120-300 f/2.8 instead by going with the lower price Sigma 70-200 f/2.8 initially, or spend that difference on other lenses and flash(es) that will fit my need better than IS or VR...



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Old Mar 16, 2008, 8:51 AM   #17
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Here are a few more examples to help illustrate flash produced better results than IS could have:










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Old Mar 16, 2008, 8:54 AM   #18
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NHL wrote:
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DarkDTSHD wrote:
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Better to have VR than not.
Not necessarily and here's why:

1. If VR is used here this picture would have been totally unacceptable as only a silhouette of the subject would come out. Why? when you shoot under tree canopy the camera is ususally pointing up to the bright sky behind the leaves (which thoses bright spots in the background are...)
That's would be a result of selecting an inappropriate metering mode, and has nothing to do with whether image stabilization is in use or not.

NHL wrote:
Quote:
DarkDTSHD wrote:
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Better to have VR than not.
Not necessarily and here's why:

2. In poor lighting regardless of how sharp the lens is, the picture still have the appearance of poor focus because of the lack of contrast and saturation... and I can point you to many posts of folks having poor results wide open with top-end lenses.
To be sure, but how does that differ depending on the availability of VR or not?

NHL wrote:
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DarkDTSHD wrote:
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Better to have VR than not.
Not necessarily and here's why:

3. As JohnG points out a flash here makes a whole world of difference, and takes away the need for VR (or IS), as a flash pulse is so fast that it would freeze any image... I also need 1/250s because this is the shutter limit where the flash can output its maximum power to overcome the strong backlit
-> The benefit here is dual-fold as it also returns the color saturation and contrast that no IS or VR could ever done if you were to depend on it!

Except at longer focal lengths wherethe subject(s) are out of range of the flash.

Edit: I thought about it some more, and realized that the optical image stabilization systemalways projects a stabilized image out the back of the lens, so it doesn't matter whether there's a TC or tube attached. So I retracted what I said, that JimC quoted.
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Old Mar 16, 2008, 9:04 AM   #19
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So, I think if you plan at the outset to use teleconverters, you might be better off with sensor shift imagte stabilization instead of optical image stabilization.
I'm sorry. But, that doesn't make any sense at all to me (that a lens based system would have problems with stabilization using a TC because the camera may not be aware of the true focal length and aperture.

I could see the opposite being true, though. For example, Pentax models with stabilization have a way you can enter the focal length of a lens manually to help the system work better, if you are using an older lens that can't report focal length.

The "smarts" are built into the lens with a stablized lens (detection and correction of shake it senses).

If the lens is providing a corrected image to the TC, what difference would it make whether or not the camera knows what the true focal length is if it's not being reported to it for purposes of stablization?

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Old Mar 16, 2008, 9:14 AM   #20
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JimC wrote:
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So, I think if you plan at the outset to use teleconverters, you might be better off with sensor shift image stabilization instead of optical image stabilization.
I'm sorry. But, that doesn't make any sense to me at all to me (that a lens based system would have problems with stabilization using a TC because the camera may not be aware of the true focal length and aperture.

I could see the opposite being true, though.

The "smarts" are built into the lens (detection and correction of shake it senses).

If the lens is providing a corrected image to the TC, what difference would it make whether or not the camera knows what the true focal length is if it's not being reported to it for purposes of stabilization?

The camera may be aware of the corrected focal length, but the lens isn't.

In addition to the lens being aware of how long its focal length is, it also knows how far away it is from the image sensor. If you increase that distance, especially with air gaps between optical elements, then the optical image stabilization will deflect the image too much, thereby overcompensating for camera shake. It would deflect the image an appropriate amount for the uncorrected focal length, but too much for the corrected focal length.

Edit: I thought about it some more, and realized that the optical image stabilization systemalways projects a stabilized image out the back of the lens, so it doesn't matter whether there's a TC or tube attached. So forget all that.
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