How were these shot? Presumably hand held?Well to give you an idea these were my findings (passed on to Intro2020 the UK distributor / support for Tamron):
Overall image
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VC off
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VC on
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I could repeat that test any number of times and predictable results.
You're probably right, though I did read all of the OP and I based my comment on that but I misread the purpose of the tripod base shot
I think we might just be expecting too much from our equipment if we are picking holes in images shot at 800 mm with a SS of 1/100 but I see the point of the overall discussion.
That said, using IS/VR/OS is a fairly basic thing to get right is it not?
How were these shot? Presumably hand held?
I have the issue with the VC of my Tamron 24 - 70 2.8, hand held at 'moderate' shutter speeds (1/125 @ 70mm, f2.8), VC on is a softer image with the introduction of a hint of blur vs VC off which is pin sharp. Repeatable results across any number of frames, three different copies of the lens (with serial numbers significantly different), all new direct from Amazon UK.
I found another case on DP review with virtually identical results from 2013 : http://www.dpreview.com/forums/post/52316394
All lens based IS/VR has to be "activated" with a button press... otherwise it would just eat batteries. Sensor based IS just tends to be on (if enabled) and eats batteries.i dont know if canikon vr is always active, but with the sigma one your ment to half press shutter button to get it to settle or spin up
i think the shutter has a effect too, ive got silly sharp shots with my sigma dps at low speed, leaf shutter
The movement seen in live view on a tripod is "different" than with IS/VR off... You will (should) see a stable image that occasionally "jumps" to a new stable position.
....That has been my experience too, Bill, on Canon Image Stabilisation (IS) when using LiveView (LV). I also notice alarming camera body movement as the shutter sounds but I guess that must be on the shutter mechanism's return after the actual shot is taken? However, the results are all sharp on that session regardless of my IS settings when on a Gitzo Systematic tripod nearly flat and low on the ground so rock solid.
Similar to what I find at higher SS's... nothing one would say is obviously VR induced... could easily be attributed to missed focus.Well to give you an idea these were my findings (passed on to Intro2020 the UK distributor / support for Tamron):
I could repeat that test any number of times and predictable results.
In my case not missed focus, i can hit 10 shots vc off perfect and 10 shots vc on with the induced blur. I also performed controlled tests (all still hand held) with a focus chart and the focus didn't shift but the quality of the in focus elements did.Similar to what I find at higher SS's... nothing one would say is obviously VR induced... could easily be attributed to missed focus.
Then trigger the camera in timer mode so you can watch the laser dot closely... if it moves around during the exposure you have an issue.
No-one is saying VR doesn't/can't work and be of a benefit... There's just a question of when it may be potentially detrimental. This will certainly be VR/IS version dependent...it will also be FL/body/technique dependent I think.Ok, these images were shot with a Sigma 105mm OS handheld at 1/50th (iso 1600) at f/4, raws but converted straight to jpeg.
I did a few test shots and each time, same results.
Not scientific (and yes the crops are slightly different but the image is unaffected) but a real world application. I'd say OS certainly worked well here.
My point was not that it *was* missed focus, but that VR could be affecting some images and you would be likely to attribute it to missed focus instead.In my case not missed focus, i can hit 10 shots vc off perfect and 10 shots vc on with the induced blur. I also performed controlled tests (all still hand held) with a focus chart and the focus didn't shift but the quality of the in focus elements did.
This is a "hands off" test (timer or remote release)Thanks Steven
is this a hands off exercise on a very good tripod locked down or normal shooting?
I still see movement on the LV screen if I use delayed release ........... holding the lens as steady as possible, with full weight on the middle part ..................or hands off or with any other technique that I have tried ...... there always seems to be some movement there with every lens that I have and every camera body
Wimberly head and Gitzo tripod
you mention issue what would that be ......... I need to still improve my technique or something else?
Ah, it's the way i read it sorryMy point was not that it *was* missed focus, but that VR could be affecting some images and you would be likely to attribute it to missed focus instead.
This is a "hands off" test (timer or remote release)
Your problem is likely the Wimberly gimbal head. It has too many pivot points and too much leverage to be rock steady... just putting the camera out there on the platform is similar to raising the center column. It's not really meant to be "rock steady," that's not what a gimbal head is for...It could also be leg/column extension etc...
Your problem is likely the Wimberly gimbal head. It has too many pivot points and too much leverage to be rock steady... just putting the camera out there on the platform is similar to raising the center column. It's not really meant to be "rock steady," that's not what a gimbal head is for...It could also be leg/column extension etc...
At 600mm everything becomes a bit more critical...I have a heavy Arca Swiss head ...... I try it with that, although with a 600mm it gets a bit balance critical
Well to give you an idea these were my findings (passed on to Intro2020 the UK distributor / support for Tamron):
Overall image
View attachment 33385
VC off
View attachment 33386
VC on
View attachment 33387
I could repeat that test any number of times and predictable results.
Nah. With shorter FL's and lower SS's (the kind of stuff you would normally handhold and use VR) it works pretty well, certainly not any worse than without VR. ("active mode" is meant for when something is moving you)sk66 mate, your lenses or camera is broken or something, your getting odd results - hand held with IS/OS/VR on = clear shots for the rest of us.
Nah. With shorter FL's and lower SS's (the kind of stuff you would normally handhold and use VR) it works pretty well, certainly not any worse than without VR. ("active mode" is meant for when something is moving you)
But combined w/ a tripod (unless tripod aware) or higher SS's, not so much. And I don't think it's as effective at long FL's and high resolution as it's advertised to be.
Nah. With shorter FL's and lower SS's (the kind of stuff you would normally handhold and use VR) it works pretty well, certainly not any worse than without VR. ("active mode" is meant for when something is moving you)
But combined w/ a tripod (unless tripod aware) or higher SS's, not so much. And I don't think it's as effective at long FL's and high resolution as it's advertised to be.
IS / VR is most effective at long FLs. At short FLs you can get away with longer shutter speeds anyway (UWAs anyone?)
And why would you use IS/VR when on a tripod? Most people know not to do that for obvious reasons, and secondly, it's on a tripod, so why would you need it anyway?
It would be better if you start at the beginning and read the thread...
The purpose of using it while on a tripod was to show what VR issues can look like while eliminating the other (confusing) potential causes for the image degradation. I know I've had VR *cause* IQ issues when used "correctly," and also when used at higher SS's. Other's in this thread have noted similar results.
If you don't know what VR caused issues might look like you would probably just blame it on soft focus/motion blur... (at higher SS's it *is* motion blur; of the moving lens elements)
TBH I thought the iq issues caused in your bird shot looked like they were caused by the use of a UV or "protective" filter on a long lens. I asked if one was used and it wasn't answered (unless I've missed it). It's still a point I'm curious about. Particularly because of the nasty bokeh which I'm sure isn't typical of that lens.It would be better if you start at the beginning and read the thread...
The purpose of using it while on a tripod was to show what VR issues can look like while eliminating the other (confusing) potential causes for the image degradation. I know I've had VR *cause* IQ issues when used "correctly," and also when used at higher SS's. Other's in this thread have noted similar results.
If you don't know what VR caused issues might look like you would probably just blame it on soft focus/motion blur... (at higher SS's it *is* motion blur; of the moving lens elements)
But combined w/ a tripod (unless tripod aware) or higher SS's, not so much. And I don't think it's as effective at long FL's and high resolution as it's advertised to be.
I must have missed your question... Only the required "plain" drop in filter was in place (400/2.8 VRII).TBH I thought the iq issues caused in your bird shot looked like they were caused by the use of a UV or "protective" filter on a long lens. I asked if one was used and it wasn't answered (unless I've missed it). It's still a point I'm curious about. Particularly because of the nasty bokeh which I'm sure isn't typical of that lens.
This part of your post is why I and others have questioned the tripod issue again as you stated its not of benefit on a tripod or with high SS, both occasions where you wouldn't use it anyway. So a rather moot point and this comes across differently to simply using your tripod shot as a control image.
I was aware of the standard, but I had never read it...Lens manufacturers these days usually use the CIPA standards for things like this, here http://www.cipa.jp/image-stabilization/index_e.html The test method I use for magazine reviews usually ties in with that pretty closely.
the determination level for image stabilization performance was set to 63 um
<snip>
And if you use longer FL's with high resolution sensors (most of them these days) my experience says you should use much faster SS's (i.e. 1/2xFL min) which puts it outside of VR use.
<snip>
I was aware of the standard, but I had never read it...
I found this interesting:
For a D8xx with 4.88um pixels that would equate to an ~13 pixel offset; certainly acceptable for the postcard size output print it was based on...
It is also interesting to note that the rating is based upon the average of ~200 images and that outliers are discounted from the average... that means "up to x-stops" means you can expect occasional results that are significantly worse, and occasional results that are better than advertised.
Just more evidence that you should try to avoid needing it as opposed to readily relying on it.
I must have missed your question... Only the required "plain" drop in filter was in place (400/2.8 VRII).
That kind of depends on what you consider a "high SS." If you use the ROT 1/FL you might have issues if you frequently work at long FL's like I do (400mm+). And if you think of it as "tripod" instead of "stability" you might run into issues as well (i.e. used with a pad). Or if you use it with a gimbal head as recommended... And many never turn VR off because they have never seen/recognized an issue, or if they do it's only when mounted on a tripod and only because they're "not supposed to use VR."
And if you use longer FL's with high resolution sensors (most of them these days) my experience says you should use much faster SS's (i.e. 1/2xFL min) which puts it outside of VR use.
I thought the first post where I stated I misused VR on a tripod in order to exasperate the issue made it clear...
The CIPA standard is certainly generous; I am usually 0.5 to 1.0 stops less optimistic at the end of the day, but not a million miles different.
If you mean the 1/.5x sampling rate (~1/500) Thom notes, then yes... but I can't state with any certainty that 1/500 is applicable across the board. IS/VR systems vary/improve. And even if it *can't* "technically" help, that doesn't mean it *will* hurt.Not sure what you mean by this. Is it the 'Thom Hogan effect'?
In response to an earlier question as to my stupidity...It did. But then the post I quoted kind of contradicted that, as why state the obvious as it was a control shot?
Definitely very generous... Their "acceptable COC" of 63um is based upon viewing a "postcard" from an average distance of 72cm/~2.5ft. I'm guessing the "most popular postcard size" is A6/4x6 (they show it as being smaller than A5). Compared to the (arguably low) "COC standard" of viewing an A4/8x10 from 25cm/1ft, it's not even in the same ballpark...
I'm surprised your results do not differ more greatly.
If you mean the 1/.5x sampling rate (~1/500) Thom notes, then yes... but I can't state with any certainty that 1/500 is applicable across the board. IS/VR systems vary/improve. And even if it *can't* "technically" help, that doesn't mean it *will* hurt.
There are so many variables, and it can be hard to discern the cause. And this CIPA standard all just reinforces my opinion which is:
Do not use VR "incorrectly." Do not enable VR if you do not *need* VR. Try to avoid needing VR if possible (use higher min SS's with more demanding sensors). And don't count on VR fixing your problems when you do need it (i.e. maybe take more images).
I understand the "a standard is better than no standard" approach... and I agree that it is. At least it's "relative."I know where you're coming from and to some extent I agree. But I use a fairly generous standard of 'acceptable' sharpness partly so that my results don't vary too far from the CIPA standard - it would only serve to confuse. The other thing is, it doesn't matter what standard of sharpness is used (within reason). If my tests, to my standard, come out with a three stops improvement over normal hand-holding, then your tests to your standard should show a similar level of improvement.
*For me* (understanding I primarily shoot wildlife/birds with very long FL's w/ D810) my minimum desired SS is 1/2xFL. Or 1/FL if using monopod/rest/aid. Using those guidelines (at any FL really) I have never seen an improvement from IS/VR, only the occasional result I believe VR degraded. I'll push these rules if using a lower resolution sensor, but not using VR to do so. I can't say I've ever seen an improvement from VR above 1/500, but that kind of goes with the previous rule. I have seen VR degrade an image below 1/500 when combined with a stability aid (not a locked tripod).So when do you not need IS/VR? At what point does this extraordinarily effective technology cease to be a benefit, and actually become a liability?
<snip> ...I can't say I've ever seen an improvement from VR above 1/500... <snip>
Yes, I am serious. What were you shooting?You can't be serious. Try hand-holding an unwieldy monster like the huge and front-heavy Sigma 150-600 S on a blustery day, as I did. Very real, significant and consistently better sharpness with OS on than off at speeds a lot higher than that. Up to 1/2000sec from memory, on Canon 7D.
Yes, I am serious. What were you shooting?
I *handhold* my 400/2.8 +2x frequently... and my Sigma 120-300/2.8 +2x occasionally... both are more unwieldy than the 150-600's. But I'm not adverse to doing a test to verify.... I need to do some focus testing anyways. (I'm a bit torn between TC use VS cropping)