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09-29-2010, 04:55 PM   #76
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addition

105mm Kiron Iterations

09-30-2010, 08:31 AM   #77
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What is the most

breakable part on the ol' 110 system?
see the link above to s gandy's take on the 110 system

or

Which 110 had revealing see-through attire?

Last edited by solar1; 09-29-2011 at 08:54 AM.
10-03-2010, 09:26 AM   #78
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Additions

Lens defects

Lens repair rates

several more misc. additions
10-03-2010, 02:19 PM   #79
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new News

see in the listing above :0 )

is that new News, or - New news?

10-04-2010, 02:05 PM   #80
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additions

Radiation-induced Discoloration/lens browing/yellowing

*ist review, pophoto

Last edited by solar1; 10-04-2010 at 02:12 PM. Reason: clarification
10-05-2010, 09:59 AM   #81
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Numerous 645D additions

+ According to one shooter, Kx and eye fi card compatible for both still images and video
10-09-2010, 08:29 AM   #82
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New Addition

M42 - lens aperture control on modern dslr's
10-14-2010, 09:08 AM   #83
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Additions

Photographer Bong Manayon, Pentax Original by S Gandy + wustl lens listings + McFaddens Pentax Library and several others.

10-23-2010, 11:41 AM   #84
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Good to know Department: Lens Repair Data 4.0

From Lensrentals.com, this data will be superseded in near future. I decided to add this separately from the Mega List in the possible outcome that they will have a new pagesite and this page info deleted - just in case I've included it here. Useful info.

WHAT IS THIS?
We started doing this several years ago. We have a unique opportunity: we own a very large number of lenses (5,600 have passed through our system) subjected to rather harsh conditions: they get packed in boxes, tossed around by UPS, and sometimes the user isn’t as careful with them as you would be with your own lenses.
Our numbers reflect how often lenses fail under fairly harsh conditions: your personal lenses shouldn’t fail nearly as often; they aren’t subjected to rental conditions. But since all of our lenses are subject to roughly the same number of rentals per year, and the same rental conditions, it does provide some comparison about how fragile various lenses are compared to other lenses. Its not scientific, but its a bit more useful than posts on a forum going back and forth between “never had a problem with it” and “mine sucked.” For those of you interested, I’d also suggest looking at the LensPlay Database. Again, it’s not scientific, but it has responses from thousands of users, so it is a large series.

This list is NOT a comment about how good a lens is, it’s about how often it breaks under harsh conditions. Some of my favorite lenses are on this list.

WHAT IS DIFFERENT THIS TIME?
First, this will be our last Lens Repair Data report, because our new website will soon start putting the repair data for each lens on the item page in real time. I may write an editorial or two in the future about repair rates, but the up-to-date repair data for every lens will be available on its web page, so I don’t need to repeat it ever six months.

Second, we’ve doubled the number of lenses we carry since the last report so this report includes Sony, Zeiss, and other lenses that were not eligible for review previously because we didn’t have enough copies.

Finally, and this is most important: we’re doing it differently this time. Previously our numbers have been additive for an entire year–we looked at the data for one year prior to the date of the report. This report is for the 6 months period from January 1, 2010 through July 1, 2010. There are two reasons for the change:

1) We are so much larger now that we’re actually looking at as much data during this 6 month period as the previous report looked at for a one year period, so it makes a nice then versus now comparison.

2) A few months ago I wrote an article, This Lens is Soft and Other Facts in which I speculated that manufacturers quietly upgrade problem lenses fixing problems without really admitting the problem was ever there. Part of the reason I made that speculation (and that’s all it is, I have no proof at all) was the changes in repair rates we’ve seen with certain lenses. Showing the data this way demonstrates a couple of those changes.

WHAT DO THE NUMBERS MEAN?
It is an annualized repair rate of the period from January 1, 2010 through June 30th, 2010 for lenses that have failed (meaning stopped working with no obvious signs of damage). The percentage we use is simple—number of lens repairs divided by the average number of copies of that lens stocked. With this report, we then doubled the six month figures to give the annualized rate so that it is comparable to previous reports.

A dropped or physically damaged lens does not count as a repair for this list. It is probable that some lenses included in these numbers actually were damaged but there was no overt evidence that it was so. We do not accept the factory service center’s word that the failure was “secondary to shock damage,” because a number of brand new, fresh-out-of-the-box lenses that we’ve sent back for repair came back with warranty work denied because of “shock damage,” even though we sent the lens to them straight out of the manufacturer’s shipping box.
We make no comment at all on lenses that we have less than 9 copies of (we don’t think that’s particularly useful, it’s too small of a number), or on new lenses we’ve carried less than 6 months (unless something is spectacularly bad, which has only happened a few times). All of our lenses are rented with about the same frequency (we have many more copies of popular lenses than of less popular lenses), so there’s not a great difference in the amount of wear-and-tear one lens gets compared to another.

Now, for those of you who want to reach conclusions from the data, please note the following:
Our median failure rate for all lenses during the last 6 months was 5.5%.
If the lens is on the list below, we’ve had more than 9 copies during the last 6 months, and it has a repair rate significantly above the median rate.
Our lenses are less than two years old, the vast majority less than 15 months old, we rotate them out of stock regularly.

There are three reasons a lens is not on the list:
We don’t carry it. Hence, we have no comments on the Sigma 70-200 f/2.8 OS, Canon 18-55 EF-S, and a number of other lenses, because we don’t carry them.
We carry the lens but have fewer than 9 copies of it, and therefore we don’t feel any comment on reliability is appropriate (all Leica, 4/3, and Micro 4/3s lenses fit this category).

The lens has proven so unreliable we’ve stopped carrying it. The following three lenses have been discontinued for this reason:
Sigma 150-500 OS
Sigma 120-400 OS
Tamron 70-200 f/2.8

One other repair rate favorite no longer qualifies for the list because we now have less than 9 copies, the Sigma 120-300 f/2.8. Rental demand for it has dropped significantly and we just don’t carry as many copies as we used to.
If we stock the lens, it isn’t in the ‘low copy’ category mentioned above, and it’s not on this list, then its failure rate is NOT high in our experience.

THE FOLLOWING LENSES HAD FAILURE RATES AT LEAST DOUBLE THE MEDIAN RATE (5.5%)
Lens Annualized Repair Rate Typical Problems
Sony 24-70 f/2.8 ZA 30% Decentered, calibration, autofocus
Sony 70-200 f/2.8 APO 28.5% Autofocus, manual focus
Canon 18-200 IS 23% Zoom sticking, IS failure, aperture stuck
Nikon 70-300 AF-S VR 22% VR failure, autofocus failure
Nikon 50 f/1.4 AF-S G 22% AF, calibration, decentering
Nikon 70-200 f/2.8 VR II 21% Zoom sticks, VR failure, AF failure
Nikon 24mm f/3.5 PC-E 20% Loose mechanism
Nikon 14-24 f/2.8 17% Zoom sticks
Sigma 50-500 OS 18% AF failure
Tokina 12-24 f/4 PRO 14% Zoom sticks, calibration
Canon 35mm f/1.4 14% Calibration, decentered element, autofocus failure
Canon 70-200 f/2.8 IS II 13.75% Zoom sticks or catches, IS failure
Canon 100-400 IS L 13.75% IS problems, zoom sticking, calibration
Canon 28-300 IS L 12.5% Zoom sticks, autofocus
Canon 70-200 f/4 IS 12% Manual focus, autofocus, IS failure
Nikon 16-85 f/3.5-5.6 VR 12% Zoom sticks
Tokina 11-16 f/2.8 11% Calibration, zoom jammed
Canon 50 f/1.2 L 11% Calibration, autofocus
Nikon 80-400 VR 11% Zoom sticks, VR failure, autofocus sticks
Nikon 17-55 f/2.8 11% Autofocus, calibration

A FEW OBSERVATIONS. (ed: note the following carefully)
Fanboys love to misuse the list above, and one of the common things I’ve seen is,“Brand X has the most (or least) lenses on Lensrentals’ high repair rate list.” Lets keep it in perspective. There were 41 Canon, 37 Nikon, 14 Sigma, 13 Zeiss, 7 Sony, 5 Tamron, and 3 Tokina lenses (120 total) eligible to make the list. The final makeup was 7 Canon, 6 Nikon, 2 Sony, 2 Tokina and 1 Sigma lenses. Every brand seems to have some troubled and some trouble free lenses.

This is the first time period during which we’ve had enough data to show Sony lenses in this report. They definitely represented once given the opportunity, but the sample size is relatively small (for example we have 12 to 15 copies of most Sony lenses compared to over 100 copies of similar Canon and 50 copies of similar Nikon lenses) so a few repairs made a relatively high number. Then again, when 1/3 of all the copies fail, it makes you take notice.

*Ed note emphasis added: I would also add, for those who haven’t experienced an out-of-warranty repair on a Sony lens, the price will make you spit your morning coffee. If you want to know how much higher, lets just say its in proportion to the cost of a Sony lens hood compared to a Canon Lens hood. Alpha has some of the best lenses around, but say your nightly prayers that they don’t break.

For those that believe early adopters face risks, this year’s data tends to support you. Three new lenses: the Canon 70-200 f/2.8 IS II, the Nikon 70-200 f/2.8 VR II, and the Sigma 50-500 OS made the list. The models they replaced were all low-repair rate lenses.

Several lenses that have been regulars on the list previously not only dropped off, they dropped way off. The Canon 17-55 f/2.8 IS has been a fixture on this list for IS and electrical problems since we started but not only is it gone, its repair rate has dropped to 6%, right around our average. Similarly the Canon 10-22 EF-S has dropped off the list and now has one of our lowest repair rates. The Nikon 24-70, which gave us a horrible time with sticking zoom barrels when it was first introduced, now is virtually trouble free. We’ve eliminated the web-page warnings on all of those lenses. (I probably should point out again that we turn our lenses over pretty frequently, and in all three cases over half of our current copies were purchased in the last 6 months.)

The Nikon 70-300 VR, which has always been a trouble free lens, suddenly appears on the list almost entirely from electrical problems. It reminds me of a similar phenomenon we saw last year with Canon 300 f/4 IS lenses where a number of copies bought at roughly the same time had a very high problem rate. A batch of bad circuit boards, perhaps? If so, the problems will disappear with our next batch of lenses.

AND ONE LAST THOUGHT
I wrote in another article that it seems likely that manufacturers quietly correct problems with subassemblies in various lenses. We’ve seen some circumstantial evidence of that with this year’s data. Several lenses that have had high repair rates for the last couple of years are suddenly absent. Not just absent, but they’ve gone from high repair rate lenses to very low repair rate lenses.
Lens 4.0 (2010) 3.5 (2009) Repair 3.0 (2008-9) 2.0 (2008)
Canon 17-55 f/2.8 IS 7.7% 29% 25% 20%
Canon 10-22 EFS 3% 9% 17.5% 16%
Nikon 24-70 f/2.8 5% 14% NA NA
Canon 35 f/1.4 14% 10% 22% 9%
Nikon 17-55 f/2.8 11% 20% 10% 19%
Canon 100-400 14% 16% 11% 12%

The three lenses listed at the top, the Canon 17-55 and 10-22 EF-S lenses and the Nikon 24-70 have had dramatic changes in repair rates this year compared to last. However, I also want to make clear that there is always some variation in our numbers from one report to another. I’ve put the two lenses that have had the widest variation in repair rate over the last several reports (the Canon 35 f/1.4 and Nikon 17-55 f/2.8) next. As the demonstrate a change from 20% to 10% and back again can just be normal variation of our numbers. The last example, the Canon 100-400, is there just to show what our more typical lens looks like. There’s some variation, but nothing all that dramatic. The vast majority of our lenses are like this, roughly the same repair rate every period.

So what does it mean? It might be that something is slightly different in newer copies of the Canon 17-55, 10-22 and the Nikon 24-70 that has solved a reliability issue. Or it might mean nothing at all, it could just be mathematical chance.
Maybe we should take an old one and new one apart and see if there’s anything different. . . . But in the meantime, we’re going to move to using “last 6 months repair data”, which will be posted on the various lens pages, rather than overall repair data as our standard.

Roger Cicala
Lensrentals.com
September, 2010
11-03-2010, 10:53 AM   #85
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Additions

Reviews of the K-r from photography blog and ephotozine
11-09-2010, 05:22 PM   #86
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New Additions to the listing today

RPP

AF micro adjust for free - thanks to Steephill over at DPreview
12-02-2010, 09:18 AM   #87
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New Additions to the listing today

Gordon Lewis' followup on the K-7 review

Camera shutter life expectancy database

The best recent dslr's

Pentax-M 50mm f/1.7: Junk Drawer Excellence

Yoshihiko Takinami's lens tests

Jens Roesner's camera and lens info pages

Last edited by solar1; 12-02-2010 at 10:47 AM. Reason: addition of a new addition
12-02-2010, 11:00 AM   #88
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Solar 1 : Fantastic resource - many many thanks for taking the time to list these resources for us, very much appreciated.
12-03-2010, 10:48 AM   #89
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Thank you for appreciating my efforts.

QuoteOriginally posted by Frogfish Quote
Solar 1 : Fantastic resource - many many thanks for taking the time to list these resources for us, very much appreciated.
12-12-2010, 02:43 AM   #90
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New Additions

New English translations of 645, K-5 & K-R reviews;

Resolving Power of Pentax 77mm and 85mm lenses

and a bunch more
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