Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
05-13-2018, 04:42 PM - 1 Like   #1
Loyal Site Supporter
Loyal Site Supporter




Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,412
B&H Pixel Shift Review - Terrible K1 PS Image used.

B&H Photo produced a Pixel Shift comparison using Pentax, Sony, Olympus and Panasonic bodies. The review was overall pretty good in terms of the actual write-up. However, the example pixel shifted image that they used from the K1 is absolutely terrible in comparison to the others. It appears that there is some blur in it.


05-13-2018, 05:45 PM   #2
Site Supporter
Site Supporter
madbrain's Avatar

Join Date: May 2008
Location: San Jose, CA
Posts: 1,167
QuoteOriginally posted by interested_observer Quote
B&H Photo produced a Pixel Shift comparison using Pentax, Sony, Olympus and Panasonic bodies. The review was overall pretty good in terms of the actual write-up. However, the example pixel shifted image that they used from the K1 is absolutely terrible in comparison to the others. It appears that there is some blur in it.
Not sure about this, could be optics. One thing I can say is this :
"Figure 12. Detail comparison at output size from each camera" looks wrong.
For example, K-1 outputs 7360 x 4912 whereas A7R III outputs 7952 x 5304 .
That means the full Sony image should be about 8% larger in each dimension vs Pentax. That is the difference in sensor resolution.
I could tell with the naked eye that the Sony image looked too large relative to the Pentax.

So, I downloaded the figure 12 image and did crops.
A crop of the K-1 image done on my PC reveals it is about 224x188 .
Whereas the Sony image is 295x247.

The Sony image should be 8% larger in each dimension. But it is actually about 31% larger.
This probably comes down to different focal lengths or lenses being used.
The K-1 image was shot with a 15-30 zoom, and A7R III with 16-35 zoom. B&H should have been able to match the focal length between those two cameras, but they didn't.
The Sony was zoomed in much closer than the Pentax. Of course it will have more detail, in addition to having a higher resolution sensor.

I just posted this comment at B&H . Also find it a bit strange that they would just now come up with a K-1 comparison, when the K-1 came out two years ago. The A7R III came out about 6 months ago.
K-1 II was already out by the time B&H posted their review one month ago.

The other odd thing is that the A7R III is at a very different price point than the other 3 cameras. The two micro 4/3 cameras and original K-1 are all $1700, whereas the A7R III is $3200, nearly twice the price . They really in different price categories. The A7 III at $2000 should have been in the review.

Last edited by madbrain; 05-13-2018 at 05:57 PM.
05-13-2018, 05:54 PM - 1 Like   #3
Loyal Site Supporter
Loyal Site Supporter
monochrome's Avatar

Join Date: Mar 2008
Location: St. Louis, Missouri
Photos: Gallery | Albums
Posts: 24,299
Given that Sony takes influential reviewers on Press Junkets, do you suppose there is some intentional dissimulation here?

Last edited by monochrome; 05-13-2018 at 08:07 PM.
05-13-2018, 06:29 PM   #4
Site Supporter
Site Supporter
madbrain's Avatar

Join Date: May 2008
Location: San Jose, CA
Posts: 1,167
QuoteOriginally posted by monochrome Quote
Given that Sony takes influential reviewers on Press Nunkets, do you suppose there is some intentional dissimulation here?
I'm not making any suppositions, just observing that this aspect of the test is flawed.

05-13-2018, 07:49 PM   #5
Pentaxian




Join Date: Jan 2015
Location: mid nth coast,nsw
Photos: Gallery
Posts: 4,068
QuoteOriginally posted by madbrain Quote
The A7 III at $2000 should have been in the review.
Pixel shifted images with that camera are as rare as HENS TEETH!

Actually, even rarer seeing its a feature not included on that body.
05-13-2018, 10:06 PM   #6
Site Supporter
Site Supporter
madbrain's Avatar

Join Date: May 2008
Location: San Jose, CA
Posts: 1,167
QuoteOriginally posted by surfar Quote
Pixel shifted images with that camera are as rare as HENS TEETH!

Actually, even rarer seeing its a feature not included on that body.
And apparently, there is a shooting delay between each of the 4 frames in the A7R III PixelShift mode.

Looks like it was 1s before, and now a revolutionary 1s !
Sony reduces Pixel Shift interval to 0.5 seconds in a7R lll: Digital Photography Review

Of course, K-1 / K-1 II have no such delay, even for tripod mode. And can do the processing in-camera also.
05-13-2018, 10:39 PM   #7
Pentaxian




Join Date: Jan 2015
Location: mid nth coast,nsw
Photos: Gallery
Posts: 4,068
QuoteOriginally posted by madbrain Quote
Of course, K-1 / K-1 II have no such delay, even for tripod mode. And can do the processing in-camera also.
Yes, its $$$ony's first go at it...i'm sure their engineers will develop in camera processing,$$$ooner or later.

The big disadvantage of $$$onys way is that the images are not labelled PS,so you have to find which ones go with which.Thats easy if its different scenes but if you take numerous shots of the same stuff,then good luck!
05-13-2018, 11:55 PM - 1 Like   #8
Pentaxian




Join Date: Sep 2016
Posts: 618
I do not understand why testers do not use the excellent Sigma Art 35/1.4 which is available in all brands for FF cameras?
Besides, they do not say which software they use and results can be the opposite according to this particularity...

05-14-2018, 12:44 AM   #9
Pentaxian




Join Date: Jan 2015
Location: mid nth coast,nsw
Photos: Gallery
Posts: 4,068
ha ha

I'm sure DPR would like to use a high quality prime to test the Pentax FF, but they are not released yet.

I could imagine what different forums would say about testing a camera using a 3rd party lens!
05-14-2018, 12:48 AM   #10
Pentaxian




Join Date: Apr 2007
Location: Romania
Posts: 11,588
Nice try. The forums would say what they say about Imaging Resource testing with a Sigma 70mm.
05-14-2018, 12:55 AM - 1 Like   #11
Pentaxian




Join Date: Sep 2016
Posts: 618
QuoteOriginally posted by surfar Quote
I could imagine what different forums would say about testing a camera using a 3rd party lens!
Nothing except that this way would prevent another bias... Am I wrong?

PS: most of my lenses are Leica-R lenses and I am very happy with Pentax K-1 vs Canon and Nikon Gear...
05-14-2018, 01:11 AM   #12
Pentaxian




Join Date: Jan 2015
Location: mid nth coast,nsw
Photos: Gallery
Posts: 4,068
QuoteOriginally posted by teiki arii Quote
Nothing except that this way would prevent another bias... Am I wrong?
No, not wrong,probably right but the testers would be ostracised for using a 3rd party.As it was they used different lenses to test 1&2 and thats caused lots of conjecture.
05-14-2018, 02:06 AM   #13
Pentaxian




Join Date: Sep 2016
Posts: 618
QuoteOriginally posted by surfar Quote
No, not wrong,probably right but the testers would be ostracised for using a 3rd party. As it was they used different lenses to test 1&2 and thats caused lots of conjecture.
testers or brands?
05-14-2018, 07:20 AM - 1 Like   #14
Pentaxian
Rickster's Avatar

Join Date: Jun 2007
Location: SE Idaho - Rocky Mtns
Photos: Gallery
Posts: 558
QuoteOriginally posted by madbrain Quote
Not sure about this, could be optics. One thing I can say is this :
"Figure 12. Detail comparison at output size from each camera" looks wrong.
For example, K-1 outputs 7360 x 4912 whereas A7R III outputs 7952 x 5304 .
That means the full Sony image should be about 8% larger in each dimension vs Pentax. That is the difference in sensor resolution.
I could tell with the naked eye that the Sony image looked too large relative to the Pentax.

So, I downloaded the figure 12 image and did crops.
A crop of the K-1 image done on my PC reveals it is about 224x188 .
Whereas the Sony image is 295x247.

The Sony image should be 8% larger in each dimension. But it is actually about 31% larger.
This probably comes down to different focal lengths or lenses being used.
The K-1 image was shot with a 15-30 zoom, and A7R III with 16-35 zoom. B&H should have been able to match the focal length between those two cameras, but they didn't.
The Sony was zoomed in much closer than the Pentax. Of course it will have more detail, in addition to having a higher resolution sensor.

I just posted this comment at B&H . Also find it a bit strange that they would just now come up with a K-1 comparison, when the K-1 came out two years ago. The A7R III came out about 6 months ago.
K-1 II was already out by the time B&H posted their review one month ago.

The other odd thing is that the A7R III is at a very different price point than the other 3 cameras. The two micro 4/3 cameras and original K-1 are all $1700, whereas the A7R III is $3200, nearly twice the price . They really in different price categories. The A7 III at $2000 should have been in the review.
I posted ...

Julien P. Has made an important point. Really can not compare images for 'resolution' if they were taken at different focal lengths let alone different glass. Just what are we comparing? Some basic flaws here in methodology.
05-14-2018, 09:35 AM - 1 Like   #15
Site Supporter
Site Supporter




Join Date: Mar 2017
Photos: Gallery | Albums
Posts: 322
Anyone that would criticize DPR for using a single lens to compare across brands doesn't understand proper scientific testing methods. The idea is to do everything you can to reduce variables across the things being compared.
The Sigma 35 Art would be a great choice for this. It's well regarded as a high quality lens, and it's available for most mounts/brands.
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!
dslr, full frame, full-frame, k-1, k1, k1 ps image, olympus, panasonic, pentax, pentax k-1, pixel, pixel shift review, review, review terrible k1, shift, vs
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Is it possible to extract the individual PS images from a combined PS image Craigbob Digital Processing, Software, and Printing 4 04-16-2017 01:32 AM
K1 Pixel shift greyed out jeffmsc Pentax DSLR Discussion 4 02-21-2017 07:54 AM
Pixel Shift single image extraction from RAW using Fast Stone Image Viewer rgknief60 Pentax K-1 3 08-18-2016 02:37 PM
K1/Samyang 24mm Tilt/Shift and Pixel Shift DDoram Pentax K-1 3 06-25-2016 02:05 PM
K1 pixel shift question Franc Pentax K-1 21 05-29-2016 11:52 AM



All times are GMT -7. The time now is 11:31 AM. | See also: NikonForums.com, CanonForums.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