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11-19-2010, 04:37 AM   #91
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QuoteOriginally posted by falconeye Quote
I made an observation, less for the K-5 but rather for a D7000 sample shot shown.

Please, refer to Digital Cameras, Nikon D7000 Digital Camera Test Image for the original image.

It is an IR shot with a distant test chart (sitting under the bell). That's essential as the full test charts are too large to be interesting.

The interesting detail is the little zone plate chart in the center. At this distance, it is fine grain enough to show the zone plate alias pattern.

For a theory of sampling artifacts of the zone plate function ( sin[x^2+y^2] ), please refer to, e.g., http://www.cgl.uwaterloo.ca/~csk/papers/kaplan_bridges2005a.pdf

The attachment shows the center crop (200% and heavily resharpened).

You see that the zone plate alias pattern emerges at a 45° angle.

That's astonishing and a possible sign that Nikon samples the raw data in a finer pitch lattice turned 45° rather than the original grid of sensels. That, or the sensor is turned 45° which I would think is highly unlikely

I didn't open the NEF and look into it. Maybe interestig to compare though.

The K-5 images show the alias pattern at the expected 0°/90° angles.


So, I add yet another possible cause for the differences in sharpness: Different levels of sophistication in in-camera demosaicers.
Wow that's fascinating information.
I knew both systems handled aliasing differently. However I had no way to demonstrate the differences.

BTW. Imaging Resource has since re-done their still studio shoot to better reflect the K-5's capacity. And I for one am relieved that they did this because it could have mislead a great deal of people into thinking the K-5 was problematic.

BTW. have you looked at part 2. of this thread?
There are two new RAW/PEF/NEF scene shots(with resolution charts) taken with better glass. It might be helpful in assessing your findings further.

11-19-2010, 04:38 AM   #92
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QuoteOriginally posted by Gimbal Quote
Talk about rendering color differently, especially the pink cloth (and the blue) above the fiddlers elbow bottle. I have no idea which one is correct though...
Spot on observation.....
All these test pics tell us nothing if you canot actually compare with what it really looks like... which camera is closts to the pink colour??? Nobody knows....
11-19-2010, 04:55 AM   #93
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QuoteOriginally posted by falconeye Quote
I made an observation, less for the K-5 but rather for a D7000 sample shot shown.

Please, refer to Digital Cameras, Nikon D7000 Digital Camera Test Image for the original image.

It is an IR shot with a distant test chart (sitting under the bell). That's essential as the full test charts are too large to be interesting.

The interesting detail is the little zone plate chart in the center. At this distance, it is fine grain enough to show the zone plate alias pattern.

For a theory of sampling artifacts of the zone plate function ( sin[x^2+y^2] ), please refer to, e.g., http://www.cgl.uwaterloo.ca/~csk/papers/kaplan_bridges2005a.pdf

The attachment shows the center crop (200% and heavily resharpened).

You see that the zone plate alias pattern emerges at a 45° angle.

That's astonishing and a possible sign that Nikon samples the raw data in a finer pitch lattice turned 45° rather than the original grid of sensels. That, or the sensor is turned 45° which I would think is highly unlikely

I didn't open the NEF and look into it. Maybe interestig to compare though.

The K-5 images show the alias pattern at the expected 0°/90° angles.


So, I add yet another possible cause for the differences in sharpness: Different levels of sophistication in in-camera demosaicers.

Could be they are doing something different, but is it better?

Look at this: for once the K-5 looks superior.
11-19-2010, 04:56 AM   #94
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QuoteOriginally posted by Gimbal Quote
Talk about rendering color differently, especially the pink cloth (and the blue) above the fiddlers elbow bottle. I have no idea which one is correct though...
From what I've seen from looking at other cameras (e.g. D3X) and developing the K-5 DNG with natural mode colors, I'd say that the pink has a better color on the K-5 sample, but is far too saturated because of bright mode.

11-19-2010, 06:35 AM   #95
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QuoteOriginally posted by Gimbal Quote
Could be they are doing something different, but is it better?

Look at this: for once the K-5 looks superior.
I already expressed my concerns of overdoing the sharpness thing.

You just provide another example: The D7000 inner disk of a darker/more blue color will remain visible at low magnification or on small sized prints. It destroys tonality for subjects with fine texture.

Last edited by falconeye; 06-23-2012 at 03:10 AM.
11-19-2010, 06:40 AM   #96
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QuoteOriginally posted by JohnBee Quote
Yes, I've seen it.
But since I didn't comment on the particular changes due to the NR reshoot, I thought it would fit better in the context of your original thread.
11-19-2010, 11:01 AM   #97
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QuoteOriginally posted by deadwolfbones Quote
Buncha people getting upset over a few samples and condemning the model as a whole.

Stupid.
Ben is right about the sample population, but in addition to the data coming from only a few samples, there is one other tiny little detail. They are being tested with DIFFERENT LENSES.
If I look at something through my binoculars and it looks sharp, and Ben looks at the same thing through his and it looks fuzzy, would that prove my eyes are better than his?
11-19-2010, 11:17 AM - 2 Likes   #98
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I am just a pure amateur, mostly an old Squirrel Shooter, but I have learned a few things in the past five years of my DSLR experience........cameras have many settings, they have great affect on your images. There are thousands of lenses, most all of them rendering a little different results. Good shooters adjust their equipment, and adjust to their equipment....the rest just speculate and pixel peep.
Best Regards!

11-19-2010, 03:52 PM   #99
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I am not comparing with other makes and models, but sufficient to say, I don't hold to the argument of softness in the K5 images.

I judge by what I see plain and simple, and am not into highly technical speculating one against the other. I feel such exercises can only serve to alarm one more and more because it becomes a never ending pursuit of perfection.
I am not ridiculing or refuting anything that has been put in this thread, but just putting my own point of view on the K5 results.
Two of mine which I feel, bear out the quality of the K5 product :

Both taken with DA35 ltd lens on K5.
#1 : no PP sharpening at all.




#2 : Minor PP sharpening:



Any softness detected here would, IMHO, be of very little significance at all.

Summary : I am more than happy that K5 is no softer than other equivilant models.
11-19-2010, 04:11 PM   #100
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QuoteOriginally posted by Bramela Quote
I judge by what I see plain and simple, and am not into highly technical speculating one against the other. I feel such exercises can only serve to alarm one more and more because it becomes a never ending pursuit of perfection.
I am not ridiculing or refuting anything that has been put in this thread, but just putting my own point of view on the K5 results.
Two of mine which I feel, bear out the quality of the K5 product :

Any softness detected here would, IMHO, be of very little significance at all.

Summary : I am more than happy that K5 is no softer than other equivilant models.
Those are great examples too.

However, in this case, it was necessary to tackle the issue at the source. Or should we say Resource(lol). The problem I had with the entire affair is where two of the major review sites 'accidentally' shot the K-5 in(so called) sub-par conditions. And to be honest, I'm having somewhat of a hard-time accepting both of these occurances as accidental(I mean what are the odds?).

Needless to say(and sadly enough), great images such as yours and the likes would have little to no effect on the consequences that such reviews would have on the masses that would be exposed to them.

I'd like to think that we did the right thing here by tackling the issue head-on and exposing the discrepancies for what they truly were. Now(at least), we have something concrete to point too when someone cites such claims as the K-5 is or was soft based on 'insert whatever here'.

And all insecurities and fanaticism aside, I for one, cringe at the thought of what would have been, had we not raised a stink and pushed for remediation on the standing conditions by both DPReview and Imaging Resource reviews of the K-5(terrible I think).

And btw. I also raised a stink when the D7000 studio scenes were consistently shot underexposed by Imaging Resource(completely with proof). To which no offer for remediation was ever made(despite my efforts). So all in all, I consider the K-5 outcome both surprising and generous in nature.

And of course.. to the name callers and fanatics... all I can say is shame on you! At the moment where a community needs to work together, it's nice to know we can always count on those few to cast stones at those taking the initiative to help out wherever possible.
11-19-2010, 07:30 PM   #101
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your enquiring and sceptical mind

QuoteOriginally posted by JohnBee Quote
Those are great examples too.

However, in this case, it was necessary to tackle the issue at the source. Or should we say Resource(lol). The problem I had with the entire affair is where two of the major review sites 'accidentally' shot the K-5 in(so called) sub-par conditions. And to be honest, I'm having somewhat of a hard-time accepting both of these occurances as accidental(I mean what are the odds?).

Needless to say(and sadly enough), great images such as yours and the likes would have little to no effect on the consequences that such reviews would have on the masses that would be exposed to them.

I'd like to think that we did the right thing here by tackling the issue head-on and exposing the discrepancies for what they truly were. Now(at least), we have something concrete to point too when someone cites such claims as the K-5 is or was soft based on 'insert whatever here'.

And all insecurities and fanaticism aside, I for one, cringe at the thought of what would have been, had we not raised a stink and pushed for remediation on the standing conditions by both DPReview and Imaging Resource reviews of the K-5(terrible I think).

And btw. I also raised a stink when the D7000 studio scenes were consistently shot underexposed by Imaging Resource(completely with proof). To which no offer for remediation was ever made(despite my efforts). So all in all, I consider the K-5 outcome both surprising and generous in nature.

And of course.. to the name callers and fanatics... all I can say is shame on you! At the moment where a community needs to work together, it's nice to know we can always count on those few to cast stones at those taking the initiative to help out wherever possible.
I am right behind you John. I you remember I agreed with you when you noticed the softness of the IR images. The problem is a lot of posters here don't look carefully (which is odd for photographers). The other problem was that some posters think that nothing can go wrong in testing, that the K-5 tests were always positive, that K-5 is perfect etc. You raised some questions about the testing without jumping to conclusions that the K-5 was soft. You continued to enquire and get to the bottom of the problem, and came to a conclusion that was favourable to Pentax, and equally favourable to the Nikon D7000.

I must say I am not a pixel peeper, but your work with noise reduction on my RAW K-7 pictures taught me that it is better to keep trying to improve the processing and the technical aspects of image capture and sometimes it can be useful to look at 100% crops, especially if one intends to PRINT photos. Unfortunately people look at a 500 kb photo on the Internet and say Wow that's sharp! See what my D* or K* can do? It's unscientific most of the time; so thankyou John and Falk and others for adding some rigour to the discussions.
11-19-2010, 07:46 PM   #102
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I started to read through this thread but there is way to much, so whats the verdict now? Is there something wrong here? :-/
11-19-2010, 07:54 PM   #103
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QuoteOriginally posted by Abstract Quote
I started to read through this thread but there is way to much, so whats the verdict now? Is there something wrong here? :-/
The shots have since been redone and everything is as it should.
You can see a follow-up thread posted here: https://www.pentaxforums.com/forums/pentax-k-5-forum/123138-k-5-vs-d7000-soft...-part-2-a.html

Based on this, I'd say the K-5 is doing just fine amidst the competition, and that all claims of softness were due to very poor techniques and settings on the part of the reviewers. Even if that meant the K-5 seems to of been the subject of neglect in both cases(oddly enough).
11-19-2010, 08:58 PM   #104
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So, why don't we have a separate thread dedicated to "K5 sharp images" ?

JP
11-19-2010, 09:09 PM   #105
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QuoteOriginally posted by jpzk Quote
So, why don't we have a separate thread dedicated to "K5 sharp images" ?

JP
Great Idea, once agian the Pentax images look great against the competition. Not sure if these have been posted yet but here is a comparison between the K5 and the D7000 at 3200 ISO from Image Resource. I think that the K5 is very sharp, from what I have seen from my own photos anyway. If the D7000 is as good then gongrats to them, I could care less really. I think that the lens will be the weakest link, my da 50-200 still sucks, and my FA 50 1.4 seems better than ever (stopped down ofcourse). The K5 is on top here, literally!
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