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Reliability rating of N series lenses

 
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conurus
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Joined: 15 Aug 2006
Posts: 795
Location: Vancouver, Canada

PostPosted: Fri Jul 23, 2010 2:34 am    Post subject: Reliability rating of N series lenses Reply with quote

The first column of following table lists defective on arrival (DOA) rate of unconverted Contax N lenses we receive, up to October 29, 2010. Only lenses already defective before conversion are counted.

Planar 85/1.42.4%2.3%
Tele-Apotessar 400/40%0%
Planar 50/1.46.7%8.9%
Makro-Sonnar 100/2.84.8%7.7%
Vario-Sonnar 70-200/3.5-4.52.7%1.7%
Vario-Sonnar 17-35/2.89.2%12.5%
Vario-Sonnar 24-85/3.5-4.57.2%10.2%
Vario-Sonnar 28-80/3.5-5.613.5%13.1%
Vario-Sonnar 70-300/4-5.68.7%12.7%

We advise extreme caution in purchasing a used lens on the market, even if your seller appears to be reputable. Try to get your seller to guarantee that the lens will pass our tests before buying.

A second column is added on 2016/01/15 to show all failures up till that point, including converted lenses subsequently sent to Contax Japan for repair. Note how the 24-85, 17-35 and 70-300 spiked into the two-digit range. 70-300 is very prone to impact damage, but it may not be obvious from a visual inspection. After impact the lens may have difficulty autofocusing and may suffer from image quality degradation at 300mm.

24-85 and 17-35 suffered from ultrasonic motor failure. The final 'wave' of repairs to catch Contax's closure at the beginning of 2015 is comprised primarily of 17-35, 24-85 and 70-300 with very little representation from other lenses.

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Last edited by conurus on Fri Jan 15, 2016 8:41 am; edited 2 times in total
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conurus
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Joined: 15 Aug 2006
Posts: 795
Location: Vancouver, Canada

PostPosted: Sat Jan 08, 2011 6:51 pm    Post subject: Reply with quote

If we receive your unconverted N mount lens and it did not pass any test case of our test suite, it will be automatically forwarded to Contax Japan for a repair estimate. You will then have the option of accepting Contax Japan's quote and pay, or declining it and have your lens returned unrepaired and unconverted.
[edit: Contax no longer accepts any repairs, and most malfunctioning lenses are now un-fixable.]

Typical charges would be 21,000 yen for labour, 5,000 yen for parts (except for 70-300) and 1,500 yen shipping per lens, though your specific quote may be higher or lower and it is completely up to Contax Japan. We will add an additional 18% on top of Contax Japan's charges to cover our expenses such as labour to deconvert/reconvert the lens, PayPal fees, currency exchange rate spreads when we buy Japanese yen, wire transfer fees our bank charges us, as well as our shipping costs to Japan. Using today's exchange rates the total repair charge will typically be around CAN$3xx.

For some reason, many 70-300's cost significantly more to repair than other lenses. About half of them cost 20,000 yen for parts to repair on top of the 21,000 yen for labour for a total repair cost of approximately CAN$545 depending on exchange rate.


Last edited by conurus on Fri Jan 15, 2016 8:43 am; edited 6 times in total
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gatorine



Joined: 09 Dec 2006
Posts: 10
Location: South Florida

PostPosted: Mon Jan 24, 2011 12:35 am    Post subject: How do we get updates on Contax Japan Repair status? Reply with quote

Are you going to add some additional information to the tracking page so we can see where our defective lenses are in the repair process? I'd like to know when the lens arrives in Japan and when it is shipped back to you following repair at a minimum.

What is your experience with Contax Japan on previous AF system repairs? Are we looking at a couple of weeks or several months for a repair?
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gatorine



Joined: 09 Dec 2006
Posts: 10
Location: South Florida

PostPosted: Fri Jan 28, 2011 11:26 pm    Post subject: How reliable are the new AF motors? Are they the same design Reply with quote

Bo Ming,

Do you have enough data yet on the replacement motors from Contax Japan to gauge their reliability relative to the original motors, especially in the 70 - 300 N? Are they in any way redesigned or are they simply new copies of the same design that was initially installed in the 70-300 N?
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amhlee



Joined: 27 Nov 2007
Posts: 35

PostPosted: Sat Jan 29, 2011 3:48 am    Post subject: Reply with quote

Hi Bo Ming,

I have send four lense for convertion including 70-300N. It is the only lense that was not converted. Is there any problem with the lenses that I send ?
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conurus
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Joined: 15 Aug 2006
Posts: 795
Location: Vancouver, Canada

PostPosted: Mon Jan 31, 2011 4:59 am    Post subject: Reply with quote

Dear amhlee,

We have not identified any problems with your 70-300, and we will begin to work on it very shortly. Thanks!

gatorine,

I noticed no changes in the design of the motor, but even with the exact same design, workmanship and quality assurance standards may vary (hopefully for the better) over the production period.

You may keep on tracking with the lens' serial number. The tracking number to Contax Japan is shown in the "tracking" field. You will see a new column appear when the lens returns from Contax Japan to us.

Thanks!

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I am a bird and I uncovered the E, EF and N-mount communication protocols!
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conurus
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Joined: 15 Aug 2006
Posts: 795
Location: Vancouver, Canada

PostPosted: Fri Feb 04, 2011 8:49 pm    Post subject: Reply with quote

If you are purchasing your lens from eBay, you are suggested to not leave positive feedback until your lens has passed our tests.
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