TSE 17mm Blurring

[wildwoodphoto]

Please look at this image taken with the Canon TS-E 17mm f4 on a Canon EOS 5D MkIV at f7.1 ISO 320 0.3 sec. The lens is shifted down slightly.

If you look at the corners, all look sharp except top right side around the window and coffee machine area

Why is this, and can it be fixed?

[Waddizzle]

The photo is fine.  Just for fun, crop the part of the image that you feel has an issue.  What is the resolution of that cropped image?

[wildwoodphoto]

Hello, if you think the image 'is fine' perhaps you cannot see the issue?

I have attached screen grabs from the left, centre and right side. You can clearly see the blurring on the right side.LeftCentreRight

[Waddizzle]

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@wildwoodphoto wrote:

Hello, if you think the image 'is fine' perhaps you cannot see the issue?

I have attached screen grabs from the left, centre and right side. You can clearly see the blurring on the right side.

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That’s not what I asked you to do.  

You are missing the point entirely.  I assume that you shot RAW.  Crop the image and generate a JPG.  What is the resolution of the final JPG files?

Did you use autofocus?  Where is your locked AF point located?  

[wildwoodphoto]

Did you not know that the 17mm TS-E is manual focus only? 

I don't understand the relevance of what you are asking me to do, as the issue is not RAW or JPEG or resolution: the issue is coming from the lens.

If you don't have the knowledge to provide a solution, please don't contribute.

[Waddizzle]

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@wildwoodphoto wrote:

Did you not know that the 17mm TS-E is manual focus only? 

I don't understand the relevance of what you are asking me to do, as the issue is not RAW or JPEG or resolution: the issue is coming from the lens.

If you don't have the knowledge to provide a solution, please don't contribute.

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I recognize that you do not understand what I am driving at.

If you manually focus by eye, then you are 100% responsible for the image being in proper focus.  However, the lens communicates with the camera.

This not only means that the camera can report Av, it can also report the location of locked AF points if the AF system is active when the shutter is fired.  The camera can also show you where locked AF points can be as you manually focus when you use One Shot AF.

[All you have to do is press and hold AF-ON as you focus in One Shot AF.]

BTW, screenshots are not useful because they introduce additional unknowns.

I tried.  Good Luck.

[Waddizzle]

Look at the f/8 column.  Your DOF should have been quite deep.

I assume that you used a tripod.  I am not professional architectural photographer, but i did take photos of my son’s rental property.  

I used the EF 16-35mm f/2.8 II USM.  I lowered the camera so that it was midway between floor and ceiling.  I carefully leveled the camera, which straightened the walls and took the photos.

[wq9nsc]

Even though you have tremendous depth of field with a 17mm lens @ f7.1, it looks like your lack of sharpness could be coming from depth of field.  It appears to me that as you go from the far left to the center crop that sharpness is already dropping and it becomes more evident further right in the frame.  Distance from the camera to the far wall is also increasing as you move to the right in the scene.  To my eyes, it looks like the foreground in the far right crop is better than the background in terms of sharpness again indicating depth of field is the issue.

As an experiment, try retaking that scene and focus on part of the scene further removed from the camera.  This is going to throw your foreground out of sharp focus but it will be useful to see if the problematic corner now looks sharp which would indicate it is a DoF rather than lens issue.

A 17mm lens @ f7.1 with the focus optimized on a point 3 feet from the lens has a depth of field of about 6'  with limits of 2 feet close and 8 feet distant in critical focus, choose the critical focus point 7 feet from the camera and everything from 3 feet to infinity should be in critical focus.  You may need to either decrease aperture or if possible move the camera further away so that the closest item in the photo is not so near allowing the critical focus point to be chosen where all of the relevant scene is within the critical focus depth of field.

Rodger

[wildwoodphoto]

Thanks for the reply. I did as you suggested, moved the focus further into the subject and the issue appears to have gone away. 

[rs-eos]

For this image, was the lens shifted, tilted, or both?  What happens if you take an image with the lens in its default position (no tilt or shift)? Does the issue still occur?