Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-23-2008, 04:24 AM   #1
Forum Member




Join Date: Mar 2007
Location: Beijing, China
Posts: 58
PopPhoto admit using K10D AF speed data in K20D review

As it has been discussed here and elsewhere, the March 2008 issue of PopPhoto has a K20D review with AF speed data being identical to that of their K10D lab test back in Jan. 2007. It was suspected that they did not bother to test the K10D's AF performance in full detail but rather copied the K10D numbers and pasted over to the K20D review. There was also one apparent error during the process: The time for -1 EV (of the K10D) was plotted as 0 EV on K20D chart.

I posted a question to the editors on PopPhoto's forum with no response from them so far but I just saw that they responded to another thread here:

Uh-oh, shennanigans in the Pentax K20D review - Respond to Popular Photography & Imaging - PopPhoto


Online Technology Editor Jack said the following in a reply to the thread:

--- quote begins ---

FYI:

Executive Technology Editor Michael J. McNamara explains: Pentax openly admits that the K20D AF system is identical to the AF system on K10D with no claims for speed or sensitivity improvements. As noted in our several stories on the K20D, there are multiple design and performance elements that are identical between the two cameras since the K20D is actually a significant upgrade to the K10D but not a totally new camera design. Our preliminary lab findings supported the similarity in AF systems, and therefore we decided to incorporate the AF results from the K10D to minimize confusion. Had there been slight variations between the two camera models (as there would be), we would have received even more complaints after claiming both AF systems were the same. However, when the test data was incorporated into the K20D Test Results graphic in print and online, it is was accidentally transposed by one place. We have since updated the chart to correct this and believe the chart to be an accurate appraisal of how the K20D AF system performs compared to other DSLRs tested in the same manner.

--- quote ends ---

"we decided to incorporate the AF results from the K10D to minimize confusion"???

I have to say I am confused by this decision. Back in the days when they tested the K10D it was running firmware 1.00 presumably and it had no support for SDM lenses because SDM lenses were not out yet. Even if Pentax said the AF hardware is identical in the K20D, there have been revisions in firmware and most notably SDM support was added since 1.30. Since they tested the DA* 16-50 for the same March 2008 issue, at least we can expect them to re-test the AF speed using an SDM lens on the K20D and publish the full numbers. Granted, low light AF performance could still be bad and SDM may not improve speed much, but I don't think they would come out 100% identical to the K10D using body-driven AF.

I don't know about the rest of you but this is the kind of review philosophy and policy that I personally cannot agree with.

Best,

Peter

02-23-2008, 04:58 AM   #2
Veteran Member
mattdm's Avatar

Join Date: Feb 2007
Location: Boston, MA
Photos: Gallery
Posts: 2,964
Yeah, I gotta say, that explanation is a bit weak. They could have put in a little note saying "slight difference from K10D results is due to sample variation". As it is, they definitely should have said "since AF system is unchanged, we're printing the data from the K10D" in order to make the review honest.
02-23-2008, 05:03 AM   #3
Veteran Member
creampuff's Avatar

Join Date: May 2007
Location: Singapore
Photos: Gallery
Posts: 3,955
Lame backtracking by PopPhoto. Doesn't add to their credibility.
02-23-2008, 05:08 AM   #4
Pentaxian




Join Date: Apr 2007
Location: Romania
Posts: 8,406
QuoteOriginally posted by mattdm Quote
Yeah, I gotta say, that explanation is a bit weak. They could have put in a little note saying "slight difference from K10D results is due to sample variation". As it is, they definitely should have said "since AF system is unchanged, we're printing the data from the K10D" in order to make the review honest.
Has anyone noticed the AF working range is different from K10D? i.e. EV 0-19 for K10D and EV -1-20 for K20D. It looks like Pentax tweaked their AF for a (slightly) better low light performance.

02-23-2008, 05:19 AM   #5
Forum Member




Join Date: Mar 2007
Location: Beijing, China
Posts: 58
Original Poster
QuoteOriginally posted by Kunzite Quote
Has anyone noticed the AF working range is different from K10D? i.e. EV 0-19 for K10D and EV -1-20 for K20D. It looks like Pentax tweaked their AF for a (slightly) better low light performance.
If that's indeed the case, it makes PopPhoto's explanation look even worse as they said "Pentax openly admits that the K20D AF system is identical to the AF system on K10D with no claims for speed or sensitivity improvements"

Peter
02-23-2008, 05:32 AM   #6
Pentaxian




Join Date: Apr 2007
Location: Romania
Posts: 8,406
Ahh... sorry, folks. I was comparing the data from dpreview (in case of the K10D) with the data from the K20D manual.
The K10D manual (I've just checked) has the same EV -1-18 range, so the dpreview is wrong (copy/paste? ).
02-23-2008, 06:26 AM   #7
Veteran Member
Tom M's Avatar

Join Date: Aug 2007
Location: Lincoln Park, NJ
Photos: Gallery
Posts: 782
I wrote the editor as well.. It's a BS excuse and goes to show how irresponsible their reviews are. In all honesty, they should ALWAYS check ALL focus modes - and that should include trap-focus etc. Not to mention, just who do they think they're kidding? The K20D kit lens is the DA 18-55MK II, and the K10D kit lens was the DA 18-55 - AF is highly effected by the lens used for testing.
02-23-2008, 07:00 AM   #8
Site Supporter




Join Date: Sep 2006
Location: midwest, United States
Photos: Gallery
Posts: 3,222
If they are going to take every companies word for the specs of their product why do ANY testing? Every camera company puts out a page or more of specs with their dslr. Truthfully, they aren't able to do a proper review anymore. Every review has major mistakes. They knocked the K20D because there aren't big SD cards. There are 16g from everyone. A couple have announced 32g (these may be available now). Largest for CF is 32g with 48g announced (maybe shipping).
They just need filler to put between their ads. Figure the mag is headed for the great beyond in a few years. They don't do anything very well. They got caught being lazy or dishonest. Should have also tested SDM focusing. One of the reasons I send "subscription" money to this forum instead op Pop Photo. The user tests here are worth so much more.
thanks
barondla

02-23-2008, 07:08 AM   #9
ogl
Pentaxian
ogl's Avatar

Join Date: Dec 2007
Location: Siberia
Photos: Gallery | Albums
Posts: 7,112
How can we trust to other figures from this co-called REVIEW?
It's MUCH worse that Phil made at dpreview.
02-23-2008, 07:19 AM   #10
ogl
Pentaxian
ogl's Avatar

Join Date: Dec 2007
Location: Siberia
Photos: Gallery | Albums
Posts: 7,112
Why don't they make test with K20D with SDM lenses? Pentax's kit has no SDM.
Canon and Nikon have. I understand that SDM is not miracle and not helper in low light, but it's more honestly.
It will be more interested to compare Pentax AF speed with Canon/Nikon/Olympus.
'Cos I don't care AF of 18-55 with 14.6 Mp camera.
K20D are shiped in body version to the shops. No kit version.
02-23-2008, 08:01 AM   #11
Veteran Member




Join Date: Nov 2006
Location: Hong Kong
Posts: 1,934
Well Done, Peter!

Peter, thanks for making the query and now we've got their answers. Btw, I think I might the first person to point out the shift in 1EV problem in my blog for their chart which they have now admitted, too :-)

Well, as for the case, I'm totally disappointed with PopPhoto, anyway.


QuoteOriginally posted by Peter Fang Quote
As it has been discussed here and elsewhere, the March 2008 issue of PopPhoto has a K20D review with AF speed data being identical to that of their K10D lab test back in Jan. 2007. It was suspected that they did not bother to test the K10D's AF performance in full detail but rather copied the K10D numbers and pasted over to the K20D review. There was also one apparent error during the process: The time for -1 EV (of the K10D) was plotted as 0 EV on K20D chart.

I posted a question to the editors on PopPhoto's forum with no response from them so far but I just saw that they responded to another thread here:

Uh-oh, shennanigans in the Pentax K20D review - Respond to Popular Photography & Imaging - PopPhoto


Online Technology Editor Jack said the following in a reply to the thread:

--- quote begins ---

FYI:

Executive Technology Editor Michael J. McNamara explains: Pentax openly admits that the K20D AF system is identical to the AF system on K10D with no claims for speed or sensitivity improvements. As noted in our several stories on the K20D, there are multiple design and performance elements that are identical between the two cameras since the K20D is actually a significant upgrade to the K10D but not a totally new camera design. Our preliminary lab findings supported the similarity in AF systems, and therefore we decided to incorporate the AF results from the K10D to minimize confusion. Had there been slight variations between the two camera models (as there would be), we would have received even more complaints after claiming both AF systems were the same. However, when the test data was incorporated into the K20D Test Results graphic in print and online, it is was accidentally transposed by one place. We have since updated the chart to correct this and believe the chart to be an accurate appraisal of how the K20D AF system performs compared to other DSLRs tested in the same manner.

--- quote ends ---

"we decided to incorporate the AF results from the K10D to minimize confusion"???

I have to say I am confused by this decision. Back in the days when they tested the K10D it was running firmware 1.00 presumably and it had no support for SDM lenses because SDM lenses were not out yet. Even if Pentax said the AF hardware is identical in the K20D, there have been revisions in firmware and most notably SDM support was added since 1.30. Since they tested the DA* 16-50 for the same March 2008 issue, at least we can expect them to re-test the AF speed using an SDM lens on the K20D and publish the full numbers. Granted, low light AF performance could still be bad and SDM may not improve speed much, but I don't think they would come out 100% identical to the K10D using body-driven AF.

I don't know about the rest of you but this is the kind of review philosophy and policy that I personally cannot agree with.

Best,

Peter
02-23-2008, 10:09 AM   #12
JMS
Senior Member




Join Date: Oct 2007
Location: Wisconsin
Posts: 273
I just feel obligated to point out that PopPhoto uses 50mm lenses in all their AF speed tests.
02-23-2008, 03:22 PM   #13
Veteran Member
*isteve's Avatar

Join Date: Nov 2006
Location: London, England
Posts: 1,187
QuoteOriginally posted by JMS Quote
I just feel obligated to point out that PopPhoto uses 50mm lenses in all their AF speed tests.
Hardly fair then, given that the Canon versions are USM lenses. The 50 1.4 is not the fastest focusing lens in the Pentax camp either - its contrast wide open is not that great and it affects AF performance. Also many of the FA lenses are slow to focus.

You cannot say anything about AF performance unless you compare with a cross section of popular lenses on a variety of targets under controlled conditions and publish the results. I have never really seen such a test performed by any magazine.

As for pop photo, they have proved to me that their reviews are garbage and I would not take any more notice in them. I would say the same about amateur photographer in the UK too, these days anyway. They are not the magazine they once were.
02-23-2008, 04:12 PM   #14
Veteran Member




Join Date: Feb 2007
Location: Auckland
Photos: Gallery
Posts: 452
Shucks, thats disappointing to hear such a lax attitude from pop photo towards their testing procedures. I wouldnt expect a huge difference in the AF, but a difference if its present is still a difference, cutting and pasting results from a previous model is just plain lazy and unprofessional.
02-23-2008, 05:19 PM   #15
Veteran Member
*isteve's Avatar

Join Date: Nov 2006
Location: London, England
Posts: 1,187
QuoteOriginally posted by Kaimarx Quote
Shucks, thats disappointing to hear such a lax attitude from pop photo towards their testing procedures. I wouldnt expect a huge difference in the AF, but a difference if its present is still a difference, cutting and pasting results from a previous model is just plain lazy and unprofessional.
Pop photo are talking rubbish anyway. There is more to an AF system than the AF sensors. The K10D later versions and K20D support SDM lenses, so this in itself is a major change, plus the K20D support fine tuning of lenses (another upgrade to the AF system).

I am also fairly sure that the SDM algorithm has been enhanced and is much more precise (less hunting) than on the K10D. This is just a matter of tweaking the settings in the AF computer but it could make a big difference and not to test this out is sheer laziness. To cut and paste number from a different camera is not just laziness however, its downright lying.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
af, chart, k10d, k20d, pentax news, pentax rumors, popphoto, results, review, sdm, system, test
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Real World AF Speed Data. K20D and K10D Russell-Evans Pentax DSLR Discussion 16 04-12-2009 01:45 PM
af speed test on popphoto hll Pentax DSLR Discussion 10 04-16-2008 04:50 PM
PopPhoto DP1 Review k100d Pentax News and Rumors 1 03-17-2008 09:50 PM
Interesting review of k20d and AF speed PentaxPoke Pentax DSLR Discussion 2 03-12-2008 07:28 AM
K10D Review at popphoto.com KFrog Pentax DSLR Discussion 1 12-12-2006 08:34 AM



All times are GMT -7. The time now is 11:59 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top