Page 2 of 7 FirstFirst 1234 ... LastLast
Results 11 to 20 of 62

Thread: How Do You Test a New Lens?

  1. #11
    Senior Member neuroanatomist's Avatar
    Join Date
    Dec 2008
    Location
    Boston, MA
    Posts
    3,716
    Quote Originally Posted by HDNitehawk View Post
    A new item like that I usually tell the store "You call Canon and give me a different copy"
    +1

    I can understand them waiting to receive the returned item before shipping the replacement, but they should replace it as a clicking sound certainly isn't normal.

    I'd be interested to hear what Canon tells you. Either way, Adorama should replace. Email Helen if the issue remains unresolved.

  2. #12
    Senior Member
    Join Date
    Dec 2008
    Location
    Planet Earth
    Posts
    2,906
    Quote Originally Posted by neuroanatomist View Post
    I'd be interested to hear what Canon tells you.
    I would be interested to. After reading the CR thread it sounds like a batch of current lenses with the issue. It would be a surprise if it were the result of a fix of some other problem and it is now normal.

    I think more likely from the reports on CR it sounds like they got a bad component that went in the lens by accident for a period of time.

  3. #13
    Super Moderator Kayaker72's Avatar
    Join Date
    Dec 2008
    Location
    New Hampshire, USA
    Posts
    4,378
    Quick update:
    1. Adorama responded to my email from yesterday providing the return information. Also, I did reread Adorama's original response. They had said I was within 30 days, so they would exchange it, but wanted me to contact Canon first.
    2. I did call Canon. They did not hear any clicking sound in any of their copies. They recommended that I exchange the lens.


    The lens is now in a box waiting for UPS to pick it up.

  4. #14
    Senior Member neuroanatomist's Avatar
    Join Date
    Dec 2008
    Location
    Boston, MA
    Posts
    3,716
    The number of people reporting this issue suggests a bad production batch. Hope you get a good one next time!

  5. #15
    Super Moderator Kayaker72's Avatar
    Join Date
    Dec 2008
    Location
    New Hampshire, USA
    Posts
    4,378
    Me too! But, given the number of people having this issue, I am preparing myself that I may have to send a couple of lens back before they run out of this batch. Hopefully not. If Bryan is right and the DD is the month and the "C" is the batch number, I am hoping I do not get another 032 serial number again.

    BTW, I asked the Canon rep that I spoke with if they had heard of this problem and they hadn't. I thought this was odd given the number of people stating they had an issue on the CR thread, so I referenced the thread. They said that they were a technician and were not (edit) aware of the thread but did say that "Canon USA" probably was aware as they do monitor several forums. I thought that was interesting. Expected, but interesting.
    Last edited by Kayaker72; 10-23-2013 at 07:41 PM.

  6. #16
    Super Moderator Kayaker72's Avatar
    Join Date
    Dec 2008
    Location
    New Hampshire, USA
    Posts
    4,378
    I am almost done testing my third version of the 24-70 f/2.8 II. Most everything about this copy checks out, except I am concerned about two things:

    1. It may be soft at 70 mm. In comparing the "quality of focus", the 24-70 II is ~100-150 units better than the 24-105 at 24 mm and 50 mm. But the 24-70 II is equal to or less than the 24-105 at 70 mm for apertures f/4.5-f/9.
    2. In addition, at 70 mm, there is an odd dip in "quality of focus" from f/8 to f/4. Below are examples from two different runs with slightly different set ups.


    Click image for larger version. 

Name:	24-70 copy 3 @ 70 mm.jpg 
Views:	34 
Size:	35.0 KB 
ID:	2041
    Click image for larger version. 

Name:	24-70 copy 3 @ 70 mm 2.jpg 
Views:	29 
Size:	35.7 KB 
ID:	2042

    I am thinking this goes back as well. No clicking while zooming, but it is soft at 70 mm.

    Of course, this is based on my assumption that Reikan's "Quality of Focus" a reasonable approximation of sharpness...

  7. #17
    Senior Member
    Join Date
    Dec 2008
    Location
    Planet Earth
    Posts
    2,906
    I had similar charts at 70mm when I used different AFMA settings. It would peak at f/2.8 and have erratic results at other settings, but when I found the right setting it did great. Try running the same test at several different AFMA settings to see if you have similar results.

    I think Reikan only focuses on the first shot then all the aperture settings after that are at the same point.

    This looks like it might be a setting problem. I would try a few more tests.

    Use the ISO charts on the site and compare at 70mm. the 24-70mm should be better than the 24-105 especially in the corners.

  8. #18
    Senior Member
    Join Date
    Dec 2008
    Location
    Planet Earth
    Posts
    2,906
    Also, I would set up a make shift chart and take pictures with both lenses at 70mm, same lighting same target and compare the two using live view and manual focus. Do not count on the Reikan results for a quality comparison, especially if you are using the AF to take the pictures.

  9. #19
    Super Moderator Kayaker72's Avatar
    Join Date
    Dec 2008
    Location
    New Hampshire, USA
    Posts
    4,378
    Thanks Rick. I'll definitely try different AFMAs and test chart shots before returning the lens. I am traveling for work Tu-F, so if I don't get to it tonight, I'll be next weekend before I can do the tests.
    Last edited by Kayaker72; 11-11-2013 at 11:36 AM.

  10. #20
    Super Moderator Kayaker72's Avatar
    Join Date
    Dec 2008
    Location
    New Hampshire, USA
    Posts
    4,378
    Not an extensive test set up, but I did play with the AFMA settings this morning. 1/200, f/5.6, ISO 100 from ~2 ft (closer than what I ran the FoCal test). I just used the focal target.

    24-105 @ 70 mm
    Click image for larger version. 

Name:	24-105 @ 70 Center.jpg 
Views:	31 
Size:	177.8 KB 
ID:	2044

    24-70 f/2.8 II @ 70mm

    Click image for larger version. 

Name:	24-70 @70 Center -15 AFMA.jpg 
Views:	29 
Size:	181.0 KB 
ID:	2045

    I was say the 24-70 f/2.8 II is sharper than the 24-105 f/4. But, it was at -15 AFMA. FoCal's test ran at a greater distance (2.3 M) was AFMA 0 for 70 mm. Also, the AFMA, according to FoCal's results, for 24 mm was + 4. So, I am potentially ranging from +4 at 24 mm to -15 at 70 mm.

    Of course, that is comparing results from two different distances, but I wouldn't want that to matter so significantly.

    For comparison, this was the center from the 24-70 f/2.8 II @ 70 mm AFMA = 0:

    Click image for larger version. 

Name:	24-70 @70 Center 0 AFMA.jpg 
Views:	26 
Size:	131.7 KB 
ID:	2046

    I also just ran the FoCal's Aperture Sharpness test @ 70 mm with the AFMA = -15
    Click image for larger version. 

Name:	Focal AFMA -15.jpg 
Views:	48 
Size:	37.9 KB 
ID:	2052
    Last edited by Kayaker72; 11-12-2013 at 12:28 PM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •