What happened to the focus: Both photos taken using Nikon equipment and a tripod and only a few minutes apart - the time it took me to remove the telextender. Distances are in meters.

Howard5252 Loc: New York / Florida (now)

Both photos taken using Nikon equipment and a tripod and only a few minutes apart - the time it took me to remove the telextender. Distances are in meters.
When I blow up both photos so the image of the bird is the same size, the second photo is sharper. EXIF info:
PHOTO1: focus dist.= 84.14 , DOF= 4.63 (81.89~86.52)
PHOTO2: focus dist.= 84.14 , DOF= 9.33 (79.73~89.09)
Both photos were f11 and shutter speeds were virtually the same (1)= 1/400 , (2) 1/320.
What is bothering me is the Focus Distance being the same. Could it be that the bird was actually outside of the 4.63 DOF? Or is it simply the softness of added by the telextender? OR is there something else I should be aware of?

500mm + Nikon 2x Telextender

(Download)

500mm

(Download)

Camerabuff Loc: Liverpool UK

Manual focu or auto?

warrior Loc: Paso Robles CA

You might want to take a look at "Topaz Focus."

Rongnongno Loc: FL

I would think the focus point is off* and the extender adds softness to the capture, a common problem.

---
* In both captures, the branches have more details!!! That seems to indicate either an auto-focus mode or your manual focus is mainly off (use the diopter and test your eye correction.

oldtigger Loc: Roanoke Virginia-USA

Howard5252 wrote:

... EXIF info:
PHOTO1: focus dist.= 84.14 , DOF= 4.63 (81.89~86.52)
PHOTO2: focus dist.= 84.14 , DOF= 9.33 (79.73~89.09)
Both photos were f11 and shutter speeds were virtually the same (1)= 1/400 , (2) 1/320.
What is bothering me is the Focus Distance being the same. ...

assuming the exif info is correct, your problem is the extender.

Its just difficult to believe two focusing operations came up with answers less than 5 thousandths of an inch apart at 84 feet distance.

oldtigger Loc: Roanoke Virginia-USA

Howard5252 wrote:

...
What is bothering me is the Focus Distance being the same. ...

Erv Loc: Medina Ohio

Hi Howard. I think your camera front focused on the branch on the right side and not the bird, in the shot without the TC. Look at the branch and you will see in the first one it is blurry and the second one it looking pretty sharp.

Howard5252 Loc: New York / Florida (now)

Thank you. I use a single focusing point in the viewfinder and typically focus on the head of the bird. The mode was Auto Focus. I'm not looking for post camera corrections. I will re-create this again.

boberic Loc: Quiet Corner, Connecticut. Ex long Islander

Howard5252 wrote:

Both photos taken using Nikon equipment and a trip... (show quote)

What kind of focusing do you use? Averaging of some kind? Try spot focus/spot metering. May solve the problem

Apaflo Loc: Anchorage, Alaska

Howard5252 wrote:

Both photos taken using Nikon equipment and a trip... (show quote)

But is there actually a problem? I don't see one.

The second image has sharper detail on the bird's head, in the feathers. The first image has more detail in the darker areas. In both cases it is only a very slight difference. The head may have had more motion for the one image, and either processing or the difference in exposure could be a reason to see more shadow detail.

Why is VR on? You'd probably get sharper images with it off at those shutter speeds on a tripod.

The narrower DOF is obvious in the first image, with the branch that is nearest to the camera being blurred more in the first image than in the second.

I'm impressed. 84 meters is darn near a football field away, and that is doing pretty good at that distance! Your 2x TC was well worth the money! Compare that to the cost of an 800mm lens.

Apaflo Loc: Anchorage, Alaska

boberic wrote:

What kind of focusing do you use? Averaging of some kind? Try spot focus/spot metering. May solve the problem

There is no such thing as averaging focus.

oldtigger Loc: Roanoke Virginia-USA

Howard5252 wrote:

... EXIF info:
PHOTO1: focus dist.= 84.14 , DOF= 4.63 (81.89~86.52)
PHOTO2: focus dist.= 84.14 , DOF= 9.33 (79.73~89.09)
Both photos were f11 and shutter speeds were virtually the same (1)= 1/400 , (2) 1/320.
What is bothering me is the Focus Distance being the same. ...

Guess thats 84 meters rather than 84 feet but i'm still curious what exif extracter i can use on a photo that will tell me the distance to a subjects focal point to 2 1/2 decimal places at 100 meters?

Can anyone help?

Apaflo Loc: Anchorage, Alaska

oldtigger wrote:

Guess thats 84 meters rather than 84 feet but i'm still curious what exif extracter i can use on a photo that will tell me the distance to a subjects focal point to 2 1/2 decimal places at 100 meters?

Can anyone help?

No need to guess about it being meters, the OP specified that. He is correct too, and a good Exif data tool will indicate that.

The Exif data may be indicating two decimal places, but that does not mean it is accurate either. Typically lenses read distance in steps, and the camera rounds that off to a digital value. On a typical wide angle lens the steps can be huge, meaning you really don't have much idea what the actual distance is. On longer focal length lenses the distances tend to be more accurate. The two digit precision is not the accuracy of the lens' measurement though, it's an artifact of the data storage assigned by the Exif standard.

It's likely that at 80 meters the accuracy is within 5 or 10 feet.

Rongnongno Loc: FL

oldtigger wrote:

Guess thats 84 meters rather than 84 feet but i'm still curious what exif extracter i can use on a photo that will tell me the distance to a subjects focal point to 2 1/2 decimal places at 100 meters?

Can anyone help?

elementsvillage.com wrote:

source

havov wrote:

In Lightroom can you see the distance to your focus point and the depth of field and the hyperfocal distance when you own a Nikon or Canon dslr. (Not all types are included though).
You need the download a plugin:

http://www.lightroomfocuspointsplugin.com/

Rongnongno Loc: FL

I am getting irritate (is that possible?) when I see posts like there is no average focusing and not explaining.

A camera when using several point of focus does an averaging to determine a plane of focus where these point are closest to. The process shows in the camera screen with several 'hot' points that will vary when you take the capture.

When you take the capture there is indeed one single point and plane of focus BUT it is the result of an averaging.

To just say 'there is no averaging' is misleading and show a complete misunderstanding of what is taking place in a camera 'brain'.