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Problem with 24-105mm F:4 G OSS lens


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When I saw the introductory photos taken with the Sony a7RM3 outfitted with the new 24-105 F:4 G OSS I was very impressed and felt it was time for me to change from my Nikon D800 to the Sony mirror-less system.  I purchased an a7RM3 with  the new 24-105 G, the 100-400 F:4.5 GM and the 16-35 F:2.8 GM.  This combination provides a nice overall system with a nice walk around lens.

I proceeded to run some quality tests on the system with all of the lenses and have found a problem with the 24-105.  I photographed an old lens test chart that I had put together in my film days.  It uses the NBS 1952 lens resolution charts.  The charts are placed in the center and corners of the frame.

The 100-400 GM and the 16-35 GM both tested very well with 80 lines/mm everywhere in the frame, center and corners.  I tested the lenses at min, max and central focal lengths.

The 24-105 G, however, is quite different.  It tested very well with 80 lines/mm across the frame at min and max focal lengths, I was quite delighted.  When I went to 60mm the results were not good at all and when I tried stopping down to F:8 the results were even worse.  The problem I see is that the left side of the frame is very soft while the center and right side test okay.  The NBS test charts have a thin lined circle in the center and that thin line becomes doubled when it is tangent to a radius drawn from the frames center.  I returned the lens to B&H and they replaced it with another new one.  The second lens exhibits the same problem.  Since my other two lenses test okay, and the 24-105 tests okay at min and max focal lengths I feel quite certain that the problem is with the 2 lenses tested and not the camera body.

I am beginning to wonder if I just got units from a bad run or if there is a mechanical design error in the zoom rails causing misalignment.  I realize that for a great many photos this is not too great a problem, but when photographing flat surfaces it does show up.  When I shot a brick wall, left side softness was quite apparent in the mortar and brick texture.  I am thinking seriously of sending the second lens back and getting the 24-70 F:2.8 GM even though it is very heavy and does not have OSS. 

 

Has any one on the Forum seen a similar problem?

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Just for fun, after reading your post, I took a photo of my stucco wall with a horizontal crack and at F4 60mm the left side is marginally sharper than the right.  However this was just hand held shooting my wall without tripod, etc.  To this point I have been totally happy with the lens, and in more carefully controlled tests it outperformed my Sigma (Canon mount adapted).

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Guest Jaf-Photo

In nu experience, decentering in zooms show up more at certain focal lengths at certain focal distances and certain f-stops. So, your results would not be unusual for a decentered zoom. Whether this lens would be constructed to be decentered at certain settings, I doubt it. In any case you should do something about it, having the lens returned, replaced or realigned. Over time, the annoyance would just grow on you.

 

On a side note, I once had a Canon camera where the sensor was misaligned. It would only be prominent with some lenses at certain settings. The problem went away after Canon realigned the sensor.

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In nu experience, decentering in zooms show up more at certain focal lengths at certain focal distances and certain f-stops. So, your results would not be unusual for a decentered zoom. Whether this lens would be constructed to be decentered at certain settings, I doubt it. In any case you should do something about it, having the lens returned, replaced or realigned. Over time, the annoyance would just grow on you.

 

On a side note, I once had a Canon camera where the sensor was misaligned. It would only be prominent with some lenses at certain settings. The problem went away after Canon realigned the sensor.

Thanks for that information

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For those that would like to view the test file here is a link to a JPG of it on Microsoft OneDrive.  https://tinyurl.com/yb5cmmo7


The JPG was made from the RAW file in PhotoShop CC. Once you see the file click on it to see the image not a thumbnail. Then click "View Original" to bring up the file as uploaded.  Now you can click anywhere on the image to see a magnified view, and compare the left side, center, right side.  The file can also be downloaded if you wish to view in PS.

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I received the Sony 24-70mm F:2.8 GM lens to replace the 24-105 F:4 G.  This lens works as it should, 80 lines/mm corner to corner at all focal lengths.  I really would have preferred the 24-105 as a general shooting lens but could not seem to get a good one.

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For those that would like to view the test file here is a link to a JPG of it on Microsoft OneDrive.  https://tinyurl.com/yb5cmmo7

The JPG was made from the RAW file in PhotoShop CC. Once you see the file click on it to see the image not a thumbnail. Then click "View Original" to bring up the file as uploaded.  Now you can click anywhere on the image to see a magnified view, and compare the left side, center, right side.  The file can also be downloaded if you wish to view in PS.

 

Where did you find the testcharts to print out?

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Where did you find the testcharts to print out?

Oh my, I originally bought these, along with an instruction book,  from the NBS when it was so called. I bought the package around 1965.  I don't think it is available any more.  They are the NBS 1952 Resolution test targets and have to be photographed at 26 focal lengths away (target to center of lens). You might try the USA Government printing office or ANSI. https://www.appliedimage.com has it but it is very expensive.  When I got mine it came with 10 charts and the book for about $10.

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..............the NBS 1952 Resolution test targets and have to be photographed at 26 focal lengths away (target to center of lens). 

 

 

Interesting. I thought the 26x were measured from, the film plane; that would make the enlargement factor 25. A nice (round) figure making calculations in your head much easier than 26x. (With 25x just multiply by 100 and divide twice by two.)

 

I have an old test chart that needs to be photographed 40x, not 41x, from lens center, which prompts my remark here.

 

Have a nice day.

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When I saw the introductory photos taken with the Sony a7RM3 outfitted with the new 24-105 F:4 G OSS I was very impressed and felt it was time for me to change from my Nikon D800 to the Sony mirror-less system.  I purchased an a7RM3 with  the new 24-105 G, the 100-400 F:4.5 GM and the 16-35 F:2.8 GM.  This combination provides a nice overall system with a nice walk around lens.

 

I proceeded to run some quality tests on the system with all of the lenses and have found a problem with the 24-105.  I photographed an old lens test chart that I had put together in my film days.  It uses the NBS 1952 lens resolution charts.  The charts are placed in the center and corners of the frame.

 

The 100-400 GM and the 16-35 GM both tested very well with 80 lines/mm everywhere in the frame, center and corners.  I tested the lenses at min, max and central focal lengths.

 

The 24-105 G, however, is quite different.  It tested very well with 80 lines/mm across the frame at min and max focal lengths, I was quite delighted.  When I went to 60mm the results were not good at all and when I tried stopping down to F:8 the results were even worse.  The problem I see is that the left side of the frame is very soft while the center and right side test okay.  The NBS test charts have a thin lined circle in the center and that thin line becomes doubled when it is tangent to a radius drawn from the frames center.  I returned the lens to B&H and they replaced it with another new one.  The second lens exhibits the same problem.  Since my other two lenses test okay, and the 24-105 tests okay at min and max focal lengths I feel quite certain that the problem is with the 2 lenses tested and not the camera body.

 

I am beginning to wonder if I just got units from a bad run or if there is a mechanical design error in the zoom rails causing misalignment.  I realize that for a great many photos this is not too great a problem, but when photographing flat surfaces it does show up.  When I shot a brick wall, left side softness was quite apparent in the mortar and brick texture.  I am thinking seriously of sending the second lens back and getting the 24-70 F:2.8 GM even though it is very heavy and does not have OSS. 

 

Has any one on the Forum seen a similar problem?

 

I am new to the Sony System, formerly used a Nikon D810.  I bought the A7R2 and the 24-105 FE F4 G OSS lens.  The lens had to go back and I am now waiting for a new one to be shipped to my dealer.   I found that at the wide setting the lens is poor and at 105, it is unusable. I compared images shot with a borrowed 16-35 F4 with those shot with the 24-105 and the differences was like night and day with the 16-35 being far, far sharper and better quality.     I was under the impression my 24-105 was single sample failure, but what I read here suggest its a design defect.  So I need to ask, how is it that reviews of this lens were so positive? 

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When I saw the introductory photos taken with the Sony a7RM3 outfitted with the new 24-105 F:4 G OSS I was very impressed and felt it was time for me to change from my Nikon D800 to the Sony mirror-less system.  I purchased an a7RM3 with  the new 24-105 G, the 100-400 F:4.5 GM and the 16-35 F:2.8 GM.  This combination provides a nice overall system with a nice walk around lens.

 

I proceeded to run some quality tests on the system with all of the lenses and have found a problem with the 24-105.  I photographed an old lens test chart that I had put together in my film days.  It uses the NBS 1952 lens resolution charts.  The charts are placed in the center and corners of the frame.

 

The 100-400 GM and the 16-35 GM both tested very well with 80 lines/mm everywhere in the frame, center and corners.  I tested the lenses at min, max and central focal lengths.

 

The 24-105 G, however, is quite different.  It tested very well with 80 lines/mm across the frame at min and max focal lengths, I was quite delighted.  When I went to 60mm the results were not good at all and when I tried stopping down to F:8 the results were even worse.  The problem I see is that the left side of the frame is very soft while the center and right side test okay.  The NBS test charts have a thin lined circle in the center and that thin line becomes doubled when it is tangent to a radius drawn from the frames center.  I returned the lens to B&H and they replaced it with another new one.  The second lens exhibits the same problem.  Since my other two lenses test okay, and the 24-105 tests okay at min and max focal lengths I feel quite certain that the problem is with the 2 lenses tested and not the camera body.

 

I am beginning to wonder if I just got units from a bad run or if there is a mechanical design error in the zoom rails causing misalignment.  I realize that for a great many photos this is not too great a problem, but when photographing flat surfaces it does show up.  When I shot a brick wall, left side softness was quite apparent in the mortar and brick texture.  I am thinking seriously of sending the second lens back and getting the 24-70 F:2.8 GM even though it is very heavy and does not have OSS. 

 

Has any one on the Forum seen a similar problem?

 

I returned this lens to my local deal and asked to get another sample.  The lens was very soft at 24mm and unusable at 105mm I have never encountered a factory new lens displaying such deviant performance from what reviewers report.  All of the reviews I have seen of this lens is that is among the best in it class across all brands.  I wonder if the factory is having a QC issue. 

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I returned this lens to my local deal and asked to get another sample.  The lens was very soft at 24mm and unusable at 105mm I have never encountered a factory new lens displaying such deviant performance from what reviewers report.  All of the reviews I have seen of this lens is that is among the best in it class across all brands.  I wonder if the factory is having a QC issue. 

There is a lot of discussions on other forums concerning aperture dependent focus shift on a considerable percentage of the new lens. If your test shots were made at any aperture outside of f4 this might explain your problem. 

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Seems there is a focus shift or some other issue on many. Most being reported are with later SNs and earlier ones seem fine. Many of FM and DP forums are reporting the issue. Seems in AF-S and even MF that at F4 the image is sharp but as you step down to 5.6 and F8 the image is out of focus. Most noticeable in the 50-105mm range. I have been through two copies with this issue and both were recently bought. Hopefully a batch issue but Sony needs to address and fix this. When they do I will buy another. 

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For what it is worth, I decided to simple test my lens.  Nothing formal about this, just a test target, on tripod, fill the frame.  It appeared perfectly centered at several focal lengths.  At 60mm was sharp at f4.0 but  sharper at F8.0  Serial #1809868.  Really enjoying the lens, but doesn't replace my 24-70 2.8 as best overall general use lens.

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I am new to the Sony System, formerly used a Nikon D810.  I bought the A7R2 and the 24-105 FE F4 G OSS lens.  The lens had to go back and I am now waiting for a new one to be shipped to my dealer.   I found that at the wide setting the lens is poor and at 105, it is unusable. I compared images shot with a borrowed 16-35 F4 with those shot with the 24-105 and the differences was like night and day with the 16-35 being far, far sharper and better quality.     I was under the impression my 24-105 was single sample failure, but what I read here suggest its a design defect.  So I need to ask, how is it that reviews of this lens were so positive? 

 

Follow up.  

I got the second 24-105 lens from my dealer last week and finally had a chance to try it out shooting from tripod at my usual test wall.  Tried it at 24mm aperture f4, 5.6, and 8.  Tried it at 105mm same apertures.  Absolutely no complaints this lens is sharp at both 24 and 105 mm extension and sharpness increases slightly between f4 and f8.  What a relief!  I am going to enjoy using this fine lens from here on out.  What a difference from the first sample i had.  Like day and night!

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It is really unfortunate when there is so much apparent sample variation with a given lens.  I wonder what happens to all the returned/replaced lenses?  Sold by Sony as "refurbished"?  Wonder if any attempt is made to correct the flaws?

 

at 1300$ a piece they will probably try to fix it  ;)

 

Sample variations are really annoying and almost all manufacturers are affected. One reason to always test a lens before I go out and shoot with it. But in the end it is sometimes hard to say whether you actually have a good copy or a slightly subpar one. You would have to order 2 or 3 lenses every time.

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at 1300$ a piece they will probably try to fix it  ;)

 

Sample variations are really annoying and almost all manufacturers are affected. One reason to always test a lens before I go out and shoot with it. But in the end it is sometimes hard to say whether you actually have a good copy or a slightly subpar one. You would have to order 2 or 3 lenses every time.

I am aware of an individual who was told by either Adorama or B&H that he had reached the limit of exchanges they would offer him!

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My third copy arrives tomorrow. First two had the focus issue. Bought, exchanged and returned in January at BB. Ordered this one from B&H and hoping three times is a charm. If not I will sadly just return it and wait until Sony addresses the issue or new batches are released without the problem. Never had this happen before and its quite frustrating.  

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As reported on FM and DPR all samples with sn 180xxxx have been ok, but about 50% of samples with sn 181xxxx have been bad. When using AF-S, the camera focuses wide open and the stops down to shooting aperture and the resulting photo is very much out of focus if a aperture outside of f4 is used. Using AF-C the camera focuses at shooting aperture and the problem will not manifest itself.

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