Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-14-2009, 05:48 PM   #1
Veteran Member
jeffkrol's Avatar

Join Date: Sep 2006
Location: Wisconsin USA
Photos: Gallery
Posts: 8,434
Imaging resources review...

Some results with my favorite quote.........
Total dynamic range is good (at 10.7 f-stops), however the score (6.54) at the highest level is a little on the low side for a modern APS-C sensor, likely due to noise in darker tones. Indeed, when deep shadows are closely observed in K-7 images, a moderate amount of noise is visible, though there is also a lot of detail present. We find this far preferable to low noise with detail obliterated by over-aggressive noise reduction.
...............
When it comes to the Pentax K-7, as noted above, its low scores for camera JPEGs reflect Pentax' decision to leave more image noise in its files at default settings, so as to not have to trade away as much subject detail. There's quite a bit of subject detail visible in the shadows of the K-7's images, but its dynamic range rankings in Imatest are brought down by the noise that's also present. We're finding that we personally prefer this approach to cameras that smudge away subtle subject detail just to achieve lower noise levels in areas of flat tint.

Pentax K-7 Digital Camera Imatest - Initial Test - The Imaging Resource!
Enjoy........


Last edited by jeffkrol; 08-14-2009 at 05:54 PM.
08-15-2009, 03:43 PM   #2
Pentaxian
Mike.P's Avatar

Join Date: Mar 2008
Location: South Coast .. UK
Photos: Gallery
Posts: 1,734
So as I understand it they prefer the way Pentax handles noise in jpegs but because they do it that way they are going to knock the score down
08-15-2009, 06:01 PM   #3
Loyal Site Supporter




Join Date: Mar 2009
Location: Southern Indiana
Photos: Gallery
Posts: 14,940
Well, I don't think they like Pentax's jpegs. They say that they are soft and yet still have jaggys in places. I guess I wouldn't know. I have always shot in RAW and will continue to do so, but it would seem like Pentax could make a camera that would have a decent Jpeg engine.
08-17-2009, 06:30 AM   #4
ogl
Pentaxian
ogl's Avatar

Join Date: Dec 2007
Location: Siberia
Photos: Gallery | Albums
Posts: 7,112
QuoteOriginally posted by Rondec Quote
Well, I don't think they like Pentax's jpegs. They say that they are soft and yet still have jaggys in places. I guess I wouldn't know. I have always shot in RAW and will continue to do so, but it would seem like Pentax could make a camera that would have a decent Jpeg engine.


AF in numbers...

08-17-2009, 07:23 PM   #5
Forum Member




Join Date: Aug 2009
Location: South Texas
Posts: 82
Looks like imaging-resource is starting to do short video clips from the recent crop of video-enabled digicams. In most of them they shoot a very simple short scene of their dog retrieving a frisbee. Take a look at the 720 *** setting from the K-7 and compare it to the similar videos they've done with other recent camera reviews (EP-1, GH1, T1i, d5000/90). To me the K-7 has about the most pleasing 720 mode of all of them right out of the box, crisp but without as much of that harsh videocam look
08-21-2009, 04:17 AM   #6
RaduA
Guest




The final version of the review is up: Pentax K-7 Digital Camera - Full Review - The Imaging Resource! and it is indeed a very positive and thorough writing.

Enjoy!
Radu
08-21-2009, 04:58 AM   #7
Veteran Member




Join Date: Jun 2009
Location: Philadelphia
Posts: 478
It's a great write up. Makes me want one even more...
08-21-2009, 05:31 AM   #8
Senior Member
dnaseigel's Avatar

Join Date: Jan 2008
Location: Rockford, IL
Photos: Gallery
Posts: 179
QuoteOriginally posted by ogl Quote


AF in numbers...
These are eye opening numbers. Where did you find them? They somewhat confirm what I have suggested to my customers and to other retailers, but the suggestion only meets steep incredulity until I can demonstrate with like lenses.

Recently I had the opportunity to show a Nikon D300 with 50mm f/1.4G, Pentax K20D with 55mm f/1.4SDM and Canon 50D with EF 50mm f/1.4USM to a group of photo retailers who were mocking my support of Pentax. Over drinks in a dimly lit bar I could not get any of a dozen people to show me that one camera was faster or slower at AF. The only real difference amongst the three outfits was the Canon occasionaly would not lock focus.

Each admitted to being very impressed with the product, but they also said they will continue to mock my support of Pentax until they believe Pentax to be a real player in the marketplace. I find it amazing that the people who should most be "in the know" can give such light regard for Pentax. I hope they come around.

08-21-2009, 05:46 AM   #9
RaduA
Guest




QuoteOriginally posted by dnaseigel Quote
These are eye opening numbers. Where did you find them? They somewhat confirm what I have suggested to my customers and to other retailers, but the suggestion only meets steep incredulity until I can demonstrate with like lenses.
The numbers are compiled from the *Performance* tab of each review. You'll get from there a lot of nice info about the responsiveness of various cameras. Also K-7 processes much faster RAWs and RAW+Jpeg (flushing the buffer) compared to a K20D.

Regards,
Radu
08-21-2009, 06:48 AM   #10
Veteran Member




Join Date: Mar 2007
Location: Munfordville, Ky.
Photos: Gallery
Posts: 370
These are, indeed, very impressive numbers (found on the Imaging Resource website), and have me leaning heavily toward the K-7 as an upgrade to my present K10D. I've been thinking seriously about the D300, on the basis of faster continuous AF, but these numbers don't seem to justify the extra cost involved. The main question that comes to my mind has to do with the conditions under which the various tests were done. Assuming they were done with good lighting, the results cannot necessarily be extrapolated to low light. I think I'll wait until Popular Photography Magazine comes out with their test results which show AF speed at light levels from EV 12 down to EV -3. I think for my purposes (shooting high school basketball in a poorly lit gymnasium) those results would be more meaningful. I hope they release something in the next couple of months.

CN
08-21-2009, 07:30 AM   #11
RaduA
Guest




QuoteOriginally posted by Clem Nichols Quote
These are, indeed, very impressive numbers (found on the Imaging Resource website), and have me leaning heavily toward the K-7 as an upgrade to my present K10D. I've been thinking seriously about the D300, on the basis of faster continuous AF, but these numbers don't seem to justify the extra cost involved. The main question that comes to my mind has to do with the conditions under which the various tests were done. Assuming they were done with good lighting, the results cannot necessarily be extrapolated to low light. I think I'll wait until Popular Photography Magazine comes out with their test results which show AF speed at light levels from EV 12 down to EV -3. I think for my purposes (shooting high school basketball in a poorly lit gymnasium) those results would be more meaningful. I hope they release something in the next couple of months.

CN
Hi, Clem!

You may want to look at this results (compiled by falconeye after the test printed in the German magazine ColorFoto): Falk Lumo

Note that the other cameras were fitted with high end supersonic internal motors and Pentax was tested with the kit lens. In low light the K-7 is close to the pack with the other 3 other non Pentax cameras and almost twice as fast as the K20D!

Regards,
Radu
08-21-2009, 10:39 AM   #12
Veteran Member




Join Date: Mar 2007
Location: Munfordville, Ky.
Photos: Gallery
Posts: 370
Thanks for the link, Radu:

Unfortunately I find the information contained therein more confusing than enlightening, because there seems to be absolutely no correlation between the times listed in the German magazine and those listed by Imaging Resource. Surely with such a wide discrepancy there must be something I'm missing???

CN
08-21-2009, 03:23 PM   #13
RaduA
Guest




QuoteOriginally posted by Clem Nichols Quote
Thanks for the link, Radu:

Unfortunately I find the information contained therein more confusing than enlightening, because there seems to be absolutely no correlation between the times listed in the German magazine and those listed by Imaging Resource. Surely with such a wide discrepancy there must be something I'm missing???

CN
Hi again Clem!

The discrepancies are due to:

- different lenses in those 2 tests (DA 18-55 II in the German test and Sigma 70/2.8 Macro for imaging-resources);
- most likely different methodologies: ColorFoto could defocus the lens to infinite and refocus by AF to a target near by and i-r.com most likely uses a more closer approach to reality by focusing from min position to a target near by. In the first case the lens goes full stroke and the time equally depends on the camera AF speed and the lens mechanical speed (whether it has a motor inside or it's driven by the camera) in the second makes a minor correction and the speed of camera AF system is more important than the mechanical speed of the camera or in lens motor. So, IMO the kind of test done by i-r.com is more fair and comparable to general usage than full stroke done by others. Furthermore seems to me that i-m.com standardize on Sigma 70/2.8 Macro in various mounts hence leveling the field in the lens part of the equation and letting the cameras to fight for faster times through speedier AF systems.
I hope it makes sense to you this is just my opinion on the matter.

Regards,
Radu
08-21-2009, 06:26 PM   #14
Veteran Member




Join Date: Mar 2007
Location: Munfordville, Ky.
Photos: Gallery
Posts: 370
Radu:

You may very well be correct. Imaging Resource doesn't go into detail as far as I can tell on how they conduct the test, and my inability to read German prevents me from digging into their article. IMHO the figures shown in Color Foto are probably more realistic than the ones in Imaging Resource which shows the K7 with a full AF shutter latency of 93 milliseconds and the D300 with a latency of 227 milliseconds. I think everyone agrees that the K-7 is Pentax's best effort yet to achieve a competetive AF speed, but I've heard no claims that it's blazingly faster than the D300. One thing I find interesting about the CF test is that in 10EV light their results show the K-7 at 390 milliseconds to be slower than the K20D at 280 ms whereas at 3.5 EV the K-7 is much faster than the 20D. Another anomaly, or so it seems to me, is where they show the Canon 50D with a faster focus at 3.5 EV (260 ms) than it has at 10EV (280ms). I think this is highly unlikely, particularly when the other four cameras take at least 50% and in the case of the 20D roughly 300% longer to focus in the low light. FWIW, Pop Photo in their test of the D300 showed an AF speed of 330 ms at 10EV and 720 ms at 3 EV. Similar figures for the K20D were 360 ms and about 1000 ms respectively. For the EOS 40D (for some reason they never got around to doing a full test on the 50D), the times were about 390 ms and 560 ms respectively. These numbers certainly correlate much better with those from Color Foto than with the impossibly (?) low numbers from Imaging Resource. I suspect that these numbers don't tell the entire story about a camera's autofocus ability, however, because based on both sets of data the 50D should out-shoot the D300, and based on the frequent grumbling I've read on DPreview's Canon 50D forum site the feeling there seems to be that it doesn't. I've decided that my best bet for now is to keep shooting with my K10D until the dust settles, so to speak. I've really nothing to lose and with the release of the D300s and probably the 50D's video-capable successor prices for the older D300 and the 50D will probably have dropped along with (hopefully) that of the K-7.

CN
08-22-2009, 04:40 PM   #15
Pentaxian
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,862
QuoteOriginally posted by Clem Nichols Quote
I find the information contained therein more confusing than enlightening, because there seems to be absolutely no correlation between the times listed in the German magazine and those listed by Imaging Resource.
The info from the German magazine were compiled by myself so I may be able to provide some bit of extra information.

I am still confused myself.
QuoteOriginally posted by RaduA Quote
The discrepancies are due to:
- different lenses in those 2 tests (DA 18-55 II in the German test and Sigma 70/2.8 Macro for imaging-resources);
- most likely different methodologies: ColorFoto could defocus the lens to infinite and refocus by AF to a target near by and i-r.com most likely uses a more closer approach to reality by focusing from min position to a target near by.
Ok, here is the extra info:
- Focus is from infinite (1000x focal length ) down to 1.5m
- Delay is measured with 10ms accuracy, from shutter press to captured image
(the target adds one bright LED every 10ms (starting the moment the trigger is activated) and the delay is determined by simply counting them on the captured photo -- so no detection of focus confirmation beep or mirror movement).
[Source: Google translated ColorFoto test methodology]

In my own tests, I could measure delay times more in line with the ColorFoto numbers (however, my own number is more like 400 ms, not 300 ms).

I don't trust the i-r.com figures. They are inconsistent and look like some of the numbers I got when the subject was already in focus. I decided to ignore them.

Even the ColorFoto figures will have an error margin of at least 100ms or so, as is visible from the faster K20D figure whch I cannot confirm.
QuoteOriginally posted by Clem Nichols Quote
my inability to read German prevents me from digging into their article. IMHO the figures shown in Color Foto are probably more realistic than the ones in Imaging Resource which shows the K7 with a full AF shutter latency of 93 milliseconds and the D300 with a latency of 227 milliseconds.
+1
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!
camera, detail, images, imatest, k-7, noise, pentax, pentax news, pentax rumors, range, shadows, subject
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Imaging-Resource full review of K-x UnknownVT Pentax DSLR Discussion 1 03-12-2010 12:35 PM
Full K-7 review up at Imaging Resource gazonk Pentax DSLR Discussion 15 08-23-2009 08:11 AM
K-7 Full test at Imaging-resources. pcarfan Pentax DSLR Discussion 12 08-15-2009 12:46 PM
Imaging Resource K20D Review Rush2112 Pentax DSLR Discussion 5 02-17-2009 07:29 AM
Imaging Resources K10D review *isteve Pentax DSLR Discussion 9 04-06-2007 06:44 AM



All times are GMT -7. The time now is 10:57 PM. | 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