Champagne Pool

[John 2]

........................On that point (choosing Av Priority) - that wouldn't have been my first choice because choosing Av Priority then requires the monitoring of any changes in the Tv (Shutter Speed) - which is fine if one doesn't forget to monitor those changes. But I like "simple" and simple means I don't like to have to remember a lot of things about what the camera might do for me. ......................................

I suspect we have all fallen foul of that situation. Recently, I puzzled over why I couldn't achieve a shutter speed longer than 1/3 rd sec when I had a 10 stop ND fitted until I realised (too late) that the camera was set on auto ISO from my last attempts at birds in flight.

[Mike Buckley]

The image as posted (post #1) has comprehensive EXIF data embedded in it. Perhaps it is only realized, depending upon the Browser used?

I downloaded the image to my computer and my cataloging software didn't display most of the EXIF data. It didn't display the shutter speed.

Specifically I made the comment about Image Stabilization because of the clarity and edge sharpness of the immediate foreground, (i.e. a Subject Distance very close to the camera at FL = 19mm on an EOS 5D Series Camera) and a Shutter Speed at 1/125s in addition to the important fact that the Camera Mode was set to Av Priority (Aperture Priority).

Sorry, but I still don't understand why image stabilization is helpful in that situation. The same photo with regard to shutter speed could have been easily taken with a similar camera-lens combination that has no image stabilization.

[William W]

I downloaded the image to my computer and my cataloging software didn't display most of the EXIF data. It didn't display the shutter speed.

I don’t think I can help. I don’t know why that happened for you, because as I mentioned, I got a full EXIF report when I downloaded the image using a Firefox browser.

***

Sorry, but I still don't understand why image stabilization is helpful in that situation. The same photo with regard to shutter speed could have been easily taken with a similar camera-lens combination that has no image stabilization.

OK, sorry for not being clear enough. Maybe more detail about one particular element will assist:

I mentioned the “immediate foreground” and also I mentioned “(i.e. a Subject Distance very close to the camera at FL = 19mm on an EOS 5D Series Camera)” – This is one important element in my analysis and my comment.

What we know:
The lens used was FL = 19mm. We have established that the camera was hand held.

What I would like to assume for a rough analysis and to better understand my comment:
Let’s assume Peter is 5’10” tall (eyes are at 5’6” or 66”); let’s assume that the camera was perfectly horizontal; let’s assume the camera was held in Landscape orientation; let’s assume Peter did not crop any of the BOTTOM of the image: (yes I know those are quite a few ‘assumptions’ – but let’s assume anyway).

So the DOWNWARD AoV, from the horizontal for that lens will be about 32° that is about half of 64.551°, which is the Vert AoV at FL = 19mm on a 135 Format Camera.

Moving to a simple triangle to illustrate (inches and degrees) – we have:



My point being that the immediate foreground was really close to the camera: only about 8~10ft away. And it is a big and a noticeable part of the image. If Peter was tilting the camera downward (which it looks as though he was) then a better estimate could be that red/orange area is about 7~8ft from the camera . . . if Peter is a bit shorter than 5’10”. . . etc, but I am sure you get the general concept.

[important concept] If we can please for the moment forget about the FL of the lens and the “1/FL Rule for Hand Holding” Please ONLY consider the small amount of Camera Shake necessary to show a little bit of blur in any Subject which is only 8~10 ft from the camera. On that topic what I would state is -

1/125s would be ‘OK’ in many Photographers' hands for Subjects that are that close – but IMO and IME it is not a “safe” Shutter Speed to ensure that elements of the image located at that close a Subject Distance are rendered as crisp as humanly/technically possible when hand holding the camera.

So, sure, I agree that many times that shot could be made at 1/125s and not using IS and it would be a good shot – but my point is many times it might have missed and the foreground would have suffered.

Hence as we have established that Peter used IS, and we note that the 1/125s Shutter Speed is a really nice choice for the for rendition of the 'steam' (well IMO it is a nice Shutter Speed for the steam) - I concluded that the image is a good example of the usefulness of Image Stabilization on UWA lenses.

Does that make better sense of my comment?

WW

[Mike Buckley]

Thanks for the detailed explanation, Bill, as I now comprehend what you are thinking. However,...

Please ONLY consider the small amount of Camera Shake necessary to show a little bit of blur in any Subject which is only 8~10 ft from the camera.

I don't remember it ever being explained that such a situation is more conducive to displaying evidence of camera shake. Moreover, I shoot much closer on a regular basis (about 2 feet), though not with a wide angle or ultra wide angle lens, and I've never experienced a greater likelihood of the short distance being an issue.

Last, though it has been established that a lens with Image Stabilization was being used, do we have information that absolutely confirms with no doubt whatsoever that the Image Stabilization was enabled at the time of capture? Is that information displayed in the EXIF data?

[William W]

. . . I don't remember it ever being explained that such a situation is more conducive to displaying evidence of camera shake.

This topic has been discussed here at CiC before: the closer the Subject (and as a result, the greater the relative area that, that part of the Subject takes in the whole image frame), then: for any given enlargement of the image, the closer the Subject Distance, then the more likely there is exhibited blur from any given amount of shake at any given Shutter Speed.

Subject Distance is one of the many factors that should be taken into consideration when assessing a 'safe' shutter speed to arrest or reduce the resultant Image Blur from Subject Motion and/or Camera Movement.

***

Moreover, I shoot much closer on a regular basis (about 2 feet), though not with a wide angle or ultra wide angle lens, and I've never experienced a greater likelihood of the short distance being an issue.

Yes. OK, but that is more a comment on your skill level and steadiness and/or the Shutter Speeds that you typically use: your particular skill level and steadiness is not relevant to a general conclusion/comment which is based upon all the factors that are relevant OTHER THAN any one individual's skill level.

***

Last, though it has been established that a lens with Image Stabilization was being used, do we have information that absolutely confirms with no doubt whatsoever that the Image Stabilization was enabled at the time of capture? Is that information displayed in the EXIF data?

I thought that was a given by Peter's response to my previous question - but I will ask, specifically now.

Peter, was IS engaged?

WW

[William W]

can't find to old CiC thread. . .

[Mike Buckley]

Thanks for looking for it, Bill.

Though I am very careful about using a shutter speed that is fast enough to compensate for my relative lack of steadiness (faster than most people recommend because I've determined that I'm apparently less steady than most people), I wonder if the real reason I've never noticed camera shake when filling the frame with an image captured at a close distance is that I've never made a large print of such an image.

A related thought: Considering that Peter's image presented here is so relatively small, that again brings me back to the point that it doesn't seem reasonable to cite it or any similarly small image as an example of Image Stabilization being particularly helpful when using a wide angle or ultra wide angle lens. It seems to me that we should feel comfortable making that assessment in this case only after viewing part of the foreground area of the image at 100% of the full-size file.

[Mike Buckley]

Peter, was IS engaged?

To clarify that, I seem to remember that Nikon's Image Stabilization requires two things to happen at the same time: the lens must be configured to use it and the shutter release has to be held halfway down momentarily for the Image Stabilization to kick in. Keep in mind that I could be wrong about that and that I have no idea how Canon's Image Stabilization, which is being discussed here, is implemented.

[ST1]

I thought that was a given by Peter's response to my previous question - but I will ask, specifically now.

Peter, was IS engaged?

WW

Whilst I cant be absolutely certain that IS was switched on for this image. I have just looked at the lens which hasn't been used since I returned from New Zealand the lens IS switch is at the "On" position. Because of that and because I'm certain I was hand held (had I used a tripod I would have switched the IS off) I will go with "I'm 99.9% certain that for the image in question IS was on"

[ST1]

To clarify that, I seem to remember that Nikon's Image Stabilization requires two things to happen at the same time: the lens must be configured to use it and the shutter release has to be held halfway down momentarily for the Image Stabilization to kick in. Keep in mind that I could be wrong about that and that I have no idea how Canon's Image Stabilization, which is being discussed here, is implemented.

Mike my understanding of the difference between the Nikon and Canon approach to overcome camera shake is that the Canon method is built in to the lens (called Image stabilisation) and is switched on/off on the lens body. The Nikon approach (called VR) I believe is in the camera body and not the lens.

[Mike Buckley]

I'll take that as sufficient evidence that Image Stabilization was enabled.

The Nikon approach (called VR) I believe is in the camera body and not the lens.

I only have one lens with VR. (Actually, it's my wife's lens and I've never used it.) The on-off switch pertaining to VR is on the lens. My understanding is that the internal mechanism relating to VR is also inside the lens, not the camera body.

However, I seem to remember that at least one camera manufacturer (I can't remember which one) placed the internal mechanism of image stabilization inside the camera body, not the lens. I'm told that doing so makes their lenses less expensive than they would otherwise be.

[ST1]

For clarity and avoidance of doubt:-

I have tried to see if Canon's processing software (Digital Photo Professional) shows if a Lens has its image stabilisation enabled during the making of an image. Unfortunately I couldn't see any information that identified if IS was on or not within that software. I don't use this software as I find it a bit cumbersome compared to other available processing software.

The image below is a snip of the RAW file from within Canon's Digital Photo Professional (DPP4). From this you can see the active focus point (the red square) which is the centre point. You can compare this to the original image I posted you should be able to see the amount of the image that I cropped from the bottom of the frame in processing. I suspect that my feet are about two feet (no Pun intended !) below the bottom of the image. As I stated in my response to Bill's question I'm 99.9% certain that I will have had IS enabled for this image as I wasn't using a tripod.

IHTH

[William W]

. . . it doesn't seem reasonable to cite it or any similarly small image as an example of Image Stabilization being particularly helpful when using a wide angle or ultra wide angle lens. It seems to me that we should feel comfortable making that assessment in this case only after viewing part of the foreground area of the image at 100% of the full-size file.

A fair enough point.

Also related – knocking down truisms such as “IS is only useful for Telephoto Lenses” is one of a few on Bill’s hit list of passionate topics. I am comfortable acknowledging that passion could be an element that swayed and encouraged any technical assessment.

On passion – (and returning to Post #1) - a salient point is – Peter’s is a bloody good picture and had it not been bloody good, I doubt that I would have become so passionate and so involved in it. That's a big take home.

WW

[William W]

. . .I have tried to see if Canon's processing software (Digital Photo Professional) shows if a Lens has its image stabilisation enabled during the making of an image. Unfortunately I couldn't see any information that identified if IS was on or not within that software. I don't use this software as I find it a bit cumbersome compared to other available processing software.

I am 99.9% certain that neither EXIF nor any other Image file data retains information as to whether Image Stabilization is “ON” or “OFF” for any of the EOS Canon DSLR System.

I have seen what appears to be consistent report of “IS ON” or “IS OFF” as data in the “Maker Notes” for some P&S style cameras, for example the G9X, where Image Stabilization can be turned off.

The common thinking is, that Image stabilization for the EOS DSLR System is a Discrete Lens Function and that means the functionality is NOT reported via the pins to the camera body – hence not recordable in any Image Data.

I know of no document from Canon that either confirms or denies any of those suppositions concerning the reporting of IS.

WW