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11-18-2010, 07:11 AM   #16
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QuoteOriginally posted by falconeye Quote
The K-5 pixels almost come in in 2x2 blocks!! There is only minimal variation within a block. A demosaicing routine should never produce such results. I attach a second 800% crop to showcase this. What looks like a pixel are 2x2 pixels. Just look more closely!
That's just very strange. Is this consistent with any other K-5 pictures at all?

11-18-2010, 07:18 AM   #17
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To be honest I am quite confused by all these "samples"...
In another "sample post" on this forumI noticed that While the K-5 images were without any doubt softer (although I wonder if one would notice in real life) the D7000 images of the same object showed more or less aterfacty patterns around the indeed sharper lines, but again, one must wonder if you would notice that in real life....

Now we have these samples which show not so artefacty behaviour BUT I notice that the D7000 has much more "jaggy edges"(see top of Samuel Smith bottle label).
Still I wonder if it can be noticed in real life....
The purple haze over black/white edges and lines do suggest lens issues as well,
Maybe the camera is fine but as many have feared would happen the lens can't cope...

Last edited by janneman; 11-18-2010 at 07:24 AM.
11-18-2010, 07:25 AM   #18
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QuoteOriginally posted by falconeye Quote
I've not yet started my formal testing, so I don't know yet what exactly is going on here.

But for the record:

I notice that Exhibit C/D clearly shows that the AA filter on the D7000 (exhibit C) is too weak. The horizontal lines in the "Pure Brewed" label have all rainbow colors you imagine, just not the correct one: mid gray. The K-5 (exhibit D) renders just fine, be it due to AA filtering or another source of blur (defocus, lens, whatever): perfect color.

It is a known fact that Bayer filtered sensors need an AA filter and a properly adjusted sharpening operator to deliver optimum results: too weak an AA filter and you get ugly Color Moiré artifacts, too weak a sharpening operator and you get soft details. Side by side comparisons using AA filters of different strengths must use different sharpening operators too.

I noticed the colorful lines as well, but the K5 still have the false pixels in between the lines which also is a sure sign of a weak AA-filter. So I'm thinking they have done some color noise reduction even on base iso. Notice also that the thin green lines ( a little higher in picture ) are not as green as the ones from the D7000, color NR in the works?
11-18-2010, 07:29 AM   #19
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QuoteOriginally posted by Erik Quote
That's just very strange. Is this consistent with any other K-5 pictures at all?
Well, okay, these are 200% crops for some reason. Both the K-5 and D7000. The extra "pixels within pixels" are just JPEG artifacts. Nevermind.

11-18-2010, 07:46 AM   #20
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Thought I would do my own mini test

K-5 with DA* 55mm f1.4.
f5.6, ISO 100, 1/50th, Hand held.

Raw file opened with Faststone viewer, and saved as Jpeg .. then 100% crop taken same way. No processing, no sharpening, no nothing.

Personally I am happy with that.

Full picture



100% crop

11-18-2010, 08:11 AM   #21
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Of all of the people who own the K-5, not one person who's reviewed it so far that I've seen has talked about soft photos; in fact, the camera has been praised for its image quality up to this point. Now Dpreview and Image Resource do some admittedly flawed "tests" and all of a sudden the K-5 has soft photos compared to the competition. I know why they do these comparisons and I can see some value in it, but I feel like it's a hard way to actually judge cameras against one another. You're really not seeing any of these cameras at their best.

It reminds me a little of the Canon 7D produces soft photos meme that has plagued that camera since its release, yet somehow many people are happy with that camera.
11-18-2010, 08:12 AM   #22
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Canon 60d wins



11-18-2010, 08:12 AM   #23
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QuoteOriginally posted by falconeye Quote
I just had a closer look at the samples JohnBee uploaded. And I noticed a strange thing, unrelated to the AA filter thing and causing a sharpening artefact which made me take the closer look.

The K-5 pixels almost come in in 2x2 blocks!! There is only minimal variation within a block. A demosaicing routine should never produce such results. I attach a second 800% crop to showcase this. What looks like a pixel are 2x2 pixels. Just look more closely!
Falk, perhaps it would be better if you worked with the originals?

D7000, ISO100 RAW/NEF Sample;
http://216.18.212.226/PRODS/D7000/FULLRES/D7000hSLI00100_NR0.NEF

K-5, ISO100 RAW/DNG Sample;
http://216.18.212.226/PRODS/K5/FULLRES/K5hSLI00100_NR_0.DNG

Let me know if this helps.

---------- Post added 11-18-10 at 03:21 PM ----------

QuoteOriginally posted by Urkeldaedalus Quote
Of all of the people who own the K-5, not one person who's reviewed it so far that I've seen has talked about soft photos; in fact, the camera has been praised for its image quality up to this point. Now Dpreview and Image Resource do some admittedly flawed "tests" and all of a sudden the K-5 has soft photos compared to the competition. I know why they do these comparisons and I can see some value in it, but I feel like it's a hard way to actually judge cameras against one another. You're really not seeing any of these cameras at their best.
I believe both DPReview and Imaging Resources have redone their testing in an effort to correct any discrepancies.

However, I think in a case such as this one, we have a little more at our disposition than mere personal observation.

Taking for example, that Image Resource offers controlled testing with the same lens and settings from other Pentax camera's(ie, the K-7). Which makes it more likely to identify any/if discrepancies in the process.

Which raises the question.
Based on the K-5 specs, wouldn't it be fair to expect the K-5 to either match or exceed the K-7 in nominal conditions?
To which, I would say, yes it is.
Unfortunately, at this time, it looks as though the K-7 samples from Imaging Resources have better IQ than the K-5.
And though this may be due to flawed testing(I know IR mentioned this). However, since the results seem consistent with other testing sites also, I think it gives use good cause for investigation.
11-18-2010, 08:21 AM   #24
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QuoteOriginally posted by HeavyD Quote
Canon 60d wins
Seriously? I like the Canon 60D and Pentax K-5 images a little better from that selection, but those three images are for all practical purposes identical. I hate this "my camera wins" BS.
11-18-2010, 08:22 AM   #25
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Mine is fine, it's the focus/lens used

I just did my own quick and dirty test.

Lens was the DA 100 macro WR

The reason for the square pixels maybe that if you open and save in photoshop the default is for square pixels on save, there are many options.

If people wish I will upload the full size raw of this one.

This was not taken under proper test conditions with perfect lighting.


I believe the reason that the OP's images are soft is because they are out of focus. That could be user error/lens used/ lens not calibrated to the body.

Last edited by telfish; 01-30-2011 at 10:17 AM.
11-18-2010, 08:24 AM   #26
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QuoteOriginally posted by HeavyD Quote
Canon 60d wins
They all look pretty much the same. Give us some shots from your Pentax please.
11-18-2010, 08:27 AM   #27
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QuoteOriginally posted by telfish Quote
If people wish I will upload the full size raw of this one.
Please do, it looks very good.

QuoteQuote:
I believe the reason that the OP's images are soft is because they are out of focus. That could be user error/lens used/ lens not calibrated to the body.
I hope this is the case also.

However, it seems that many sites are coming-up with similar output(it makes me suspicious).
Also, I can't say for certain, but your own sample seems to have the same(sort of) softness to it as well.
Would you happen to have a K-7 that you could test it against?
In the Imaging Resource samples, I've found the K-7 to render sharper edge contrast(pixel per pixel) than the K-5 ones. Not saying that this is a definite case, but it could be an indicator as to whether or not a discrepancy truly exists.

Last edited by JohnBee; 11-18-2010 at 08:33 AM.
11-18-2010, 08:36 AM   #28
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QuoteOriginally posted by JohnBee Quote
I'm writing this in response to a series of tests that have been coming about the web lately. And I've found(even in RAW) where the K-5 seems to produce softer images than the competition. Or.. specifically, in contrast to other systems using the same sensor.
...
...

All I can say is, I do hope this is not an issue with the camera or, worst yet... a permanent condition that we will just have to live with. Though I for one would love to get to the bottom of it.
QuoteOriginally posted by telfish Quote
John,

I think you are way off base here with this post. Do you have a K5? Well I have one, my wife has one and we are both very happy with the image sharpness and the color we got out of these cameras.

I disregard these sort of torture tests because they are not really comparable. They use unlike lenses and settings so they are worthless.

Please don't start a false meme on this. It's irresponsible. I am a real world shooter and my real world results with decent glass are superb.
I don't get your point telfish. Johnbee stated that based on 'a series of web tests' he saw some softness. The examples that he posted tell us why he thinks that. What is offbase in stating an observation and presenting the basis of that observation? Should no one scrutinize the camera that you are happy with?

On another note,


QuoteOriginally posted by falconeye Quote
I've not yet started my formal testing, so I don't know yet what exactly is going on here.
Falk - do you plan to do a formal test of k-5? If so, when?


cheers
11-18-2010, 08:37 AM   #29
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QuoteOriginally posted by telfish Quote
If people wish I will upload the full size raw of this one.
My hand is up.
11-18-2010, 08:40 AM   #30
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QuoteOriginally posted by cbaytan Quote
My hand is up.
Look here: https://www.pentaxforums.com/forums/pentax-k-5-forum/123082-pentax-k-5-images...ml#post1271131
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