25mm f1.7 comparison shots...disappointed

I don't have the skills or lens inventory to do a similar test, so I appreciate another set of 'eyes' on this issue (non-issue for me, I'm quite pleased with the lens).

Tony8232 wrote:

I agree with you, there is nothing wrong with the sharpness of the Panasonic 25 f/1.7. My copy is much better than the OP's. Contrast seems OK on my sample anyway. The biggest drawback of the lens for me is its size. I also noticed the focal length to be about 27mm..

Regarding your estimate of the focal length, what's your reference? I really don't think there's any standard that applies to lens focal length. They are always approximate, and the manufacturer can call it what they like.

If you're comparing with the field of view of a zoom lens set to 25mm, that will be approximate as well and probably even less likely to be right on 25mm.

Gidday Warren

That is more than just a bit noticeable, mate ...

Can you adjust the focus trimming (micro-adjust) in the body to compensate?

Big D in SP wrote:

nzimmers wrote:

Tony8232 wrote:

I agree with you, there is nothing wrong with the sharpness of the Panasonic 25 f/1.7. My copy is much better than the OP's. Contrast seems OK on my sample anyway. The biggest drawback of the lens for me is its size. I also noticed the focal length to be about 27mm..

This ~27mm focal length is something that really has me scratching my head and thinking....

My Theories:

a) Engineered that way as a couple of extra mm's of focal length helped straighten out some performance issues (maybe with CA or distortion) and Panasonic hoped no one would notice/care

b) Factory in China was rushing production to make a big shipment and skipped an adjustment step or something else was out of tolerance. QA caught the issue and two weeks went by while Panasonic considered options and finally determined 1) They would pay factory but at a fraction of the agreed cost due to the error and 2) Panasonic hoped no one would notice/care, especially since they would be selling it at a reduced price during the holidays, and 3) every sale of a Panasonic 25mm(~ish) means one less sale of an Olympus 25mm.

Honestly, could this not be something that would be addressed through warranty?

I've increased the last line to "Bold" since that is a question I'm asking myself, because, I've done further testing on my lens and found the main problem is that it is FRONT-FOCUSING on my G7!

I'll be posting the shots showing it in a few minutes and how it compares to a Sigma 30mm. Here's just one shot to peruse. Now the question is: lens or camera??

25mm f1.7 @ f1.7

Regards,

Warren

Option 1: your focus center point is moved out of center. In many cases this is a result of focusing via touch screen. Bring center point back to the center of the screen

Option 2: your lens is de-centered.  You can check it easy when take the same shot with camera upside down.

The most important from my point of view - you have taken correct step (and shot) to display the issue.

Big D in SP wrote:

nzimmers wrote:

Tony8232 wrote:

I agree with you, there is nothing wrong with the sharpness of the Panasonic 25 f/1.7. My copy is much better than the OP's. Contrast seems OK on my sample anyway. The biggest drawback of the lens for me is its size. I also noticed the focal length to be about 27mm..

This ~27mm focal length is something that really has me scratching my head and thinking....

My Theories:

a) Engineered that way as a couple of extra mm's of focal length helped straighten out some performance issues (maybe with CA or distortion) and Panasonic hoped no one would notice/care

b) Factory in China was rushing production to make a big shipment and skipped an adjustment step or something else was out of tolerance. QA caught the issue and two weeks went by while Panasonic considered options and finally determined 1) They would pay factory but at a fraction of the agreed cost due to the error and 2) Panasonic hoped no one would notice/care, especially since they would be selling it at a reduced price during the holidays, and 3) every sale of a Panasonic 25mm(~ish) means one less sale of an Olympus 25mm.

Honestly, could this not be something that would be addressed through warranty?

I've increased the last line to "Bold" since that is a question I'm asking myself, because, I've done further testing on my lens and found the main problem is that it is FRONT-FOCUSING on my G7!

I'll be posting the shots showing it in a few minutes and how it compares to a Sigma 30mm. Here's just one shot to peruse. Now the question is: lens or camera??

It can't be the lens. It's got to be either the camera or the user.

25mm f1.7 @ f1.7

Regards,

Warren

John King wrote:

Gidday Warren

That is more than just a bit noticeable, mate ...

Can you adjust the focus trimming (micro-adjust) in the body to compensate?

I thought that this focus trimming was only necessary when focusing sensors are separate from the imaging sensor. Since focusing and image capture all happen in the same place there'd be no point to an adjustment like this.

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clengman wrote:

John King wrote:

Gidday Warren

That is more than just a bit noticeable, mate ...

Can you adjust the focus trimming (micro-adjust) in the body to compensate?

I thought that this focus trimming was only necessary when focusing sensors are separate from the imaging sensor. Since focusing and image capture all happen in the same place there'd be no point to an adjustment like this.

I don't think that's so. The E-M1 has provision for this adjustment. I don't know about other mFTs cameras.