PMA Australia speaks of a 21MP Pentax!

falconeye · 06-10-2010, 06:08 AM

Originally posted by cbaytan

As an uneducated user I sharpened other picture from Nikon HR page, with Photoshop.

Amount 200 %
Radius 0.5 Pixels
Threshold: 50 Levels

Check with the Jackson's cape!

Just sharpen properly. But I admit, unlike the test chart sample, the bill sample with AA filter isn't perfectly focussed. I had to sharpen more (FocusMagic r=2 sharpening -- both samples, the test chart (r=1) and the bill (r=2) used the sharpening parameter computed by FocusMagic).

P.S.
From the fact that you call for a weak AA filter and uneducated users do as well you cannot logically deduce that I called you uneducated

Actually, I did not.

Last edited by falconeye; 06-15-2011 at 05:29 AM.

Class A · 06-10-2010, 06:22 AM

Originally posted by wll

If the new sensor is 21 MP, in the aps-c mode how many pixels would you have ?

~8.8 MP. Just divide 21 by the square of the crop factor (= ratio between the sensor areas).

Originally posted by falconeye

BTW, you can order the 645D with or without an AA filter. So, there is no Pentax decision I could disapprove.

Interesting, I didn't know that.
Thanks for the rest of your post as well!

Originally posted by falconeye

From the fact that you call for a weak AA filter and uneducated users do as well you cannot logically deduce that I called you uneducated

Actually, I did not.

From the fact that cbaytan wrote "As an uneducated user" you cannot deduce that he thinks that you called him uneducated.

falconeye · 06-10-2010, 06:36 AM

Originally posted by Class A

From the fact that cbaytan wrote "As an uneducated user" you cannot deduce that he thinks that you called him uneducated.

And you cannot deduce I assumed he thought

But to be honest, I didn't think that cbaytan is uneducated. But I do think as well that very few educated opinions about the AA vs. no AA topic have ever been posted

And this Nikon D200HR site is a particularly bad example which tries to mislead on purpose (tries to sell something you don't need).

cbaytan · 06-10-2010, 06:56 AM

Originally posted by falconeye

But I do think as well that very few educated opinions about the AA vs. no AA topic have ever been posted

AA filter education?

I don't buy and test cameras with and without AA. Most people are trying to learn by discussing here and there, on the internet, like me.

gazonk · 06-10-2010, 07:15 AM

Originally posted by falconeye

But in general, lenses still outresolve the sensors by a large margin (in the image centers, I mean).

That's the only drawback I've noticed with my DA70, it so easily outresolves the K10D sensor that I get super ugly color moiré way too often

- often combined with labyrinths:

Class A · 06-10-2010, 07:23 AM

Originally posted by falconeye

And you cannot deduce I assumed he thought

Did you think I thought you assumed he thought?

**Digitalis** · 06-10-2010, 07:48 AM

"Perhaps it is relatively safe to do with the old MF glass? Leica should be in more trouble with their glass but seem to get away with it."

In my experience I find that lens sharpness has little to do with the appearance of moire, pixel pitch seems to be the biggest contributing factor.

"Just look at a frame from a 1536x1024 K-7 video."

the video from the k-7 is not super sampled therefore aliasing artefacts are going to be much more common with subsampled video output....besides video is a feature on the K-7 that I could live without, though live view certainly does come in handy.

"Demosaicing algorithm. It is much more challenging to write a good demosaicer for a weak AA filter. But progress has been made in this domain and e.g. Leica and Hasselblad claim to recognize and eliminate color aliasing in their firmware demosaicers. Pentax does not claim so."

though considering how often pentax announces such features, I wouldn't be surprised if they have developed such a thing.

at any rate I have explored techniques to combat moire both in camera and on the subject. capture one has a very good moire reduction tool, I am uncertain if Light room 3 has similar functionality but C1 does a very good job of it, despite their less than stellar DNG profiles.

one of the simplest ways to prevent moire is to stop a lens down to the point where such fine details are blurred from diffraction. Either that, or ask your models to avoid wearing certain fabrics.

"Canon EF-S lenses cannot be used on the 24x36mm cameras, because their rear-element design would "interfere" (i.e. collide) with the mirror. I believe they cannot even be mounted on these cameras."

you're correct on that point, though i wouldn't be surprised of Canon alters their lens mount...again, to enable EF-S lenses.

" you can order the 645D with or without an AA filter."

gee thanks Falk, now I'm going to have to order two of the blasted things...

Last edited by Digitalis; 06-10-2010 at 08:06 AM.

ogl · 06-10-2010, 08:41 AM

Originally posted by falconeye

Just sharpen properly. B
P.S.
From the fact that you call for a weak AA filter and uneducated users do as well you cannot logically deduce that I called you uneducated

Actually, I did not.

D200 never had strong AA filter.

ogl · 06-10-2010, 08:42 AM

Originally posted by gazonk

That's the only drawback I've noticed with my DA70, it so easily outresolves the K10D sensor that I get super ugly color moiré way too often

- often combined with labyrinths:

Change RAW-convertor.

falconeye · 06-10-2010, 09:14 AM

Originally posted by Digitalis

"Just look at a frame from a 1536x1024 K-7 video."

the video from the k-7 is not super sampled therefore aliasing artefacts are going to be much more common with subsampled video output

That was my point. Subsampled video frames are a nice demonstration how images look if you have no means of blurring prior to demosaicing ... no lens blur, no motion blur, no defocus blur and no AA blur. Ugly enough to make people cry for a means to blur ...

gazonk · 06-10-2010, 12:35 PM

Originally posted by ogl

Change RAW-convertor.

The image I showed was converted with PPL, which usually is better at this than Apple built-in RAW which I usually use. But in this case they were similar.

zackspeed · 06-10-2010, 03:32 PM

Originally posted by Pentaxor

and the 645D does make economic sense for Hoya? :ugh:

Oh yes,it does.
The first production Run is complete ordered and sold out

Pentaxor · 06-10-2010, 03:52 PM

Originally posted by zackspeed

Oh yes,it does.
The first production Run is complete ordered and sold out

you have to consider which target market is that. otherwise, I dont think that Pentax would make more 645D's than their midrange and starter cameras. same principle as to selling 1D's and D3's.

Class A · 06-10-2010, 04:04 PM

Originally posted by Digitalis

In my experience I find that lens sharpness has little to do with the appearance of moire, pixel pitch seems to be the biggest contributing factor.

I have a benchmark image, the roof of a house in the distance. Only a few select lenses of mine excite moiré with this roof. The majority doesn't.

Originally posted by zackspeed

The first production Run is complete ordered and sold out

Nice to hear!

Thanks for sharing.

**Digitalis** · 06-10-2010, 05:57 PM

"I have a benchmark image, the roof of a house in the distance. Only a few select lenses of mine excite moiré with this roof. The majority doesn't."

lens micro contrast, is what is to blame here...remember film? the reason why moire never occurred with film is due to the random nature of silver particles, not to mention the fact that resolution of High spatial frequencies would reach it's peak and sharply lose contrast beyond that point, We never had aliasing artefacts like we do with digital. Moire is a sensor based artefact, I won't debate if certain lenses exacerbate it or not, I'm sure some do due to higher contrast at higher frequencies.

06-10-2010, 07:15 AM	#185
gazonk Pentaxian Join Date: Feb 2009 Location: Oslo area, Norway Photos: Gallery \| Albums Posts: 3,746	Originally posted by falconeye But in general, lenses still outresolve the sensors by a large margin (in the image centers, I mean). That's the only drawback I've noticed with my DA70, it so easily outresolves the K10D sensor that I get super ugly color moiré way too often - often combined with labyrinths: Attached Images

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06-10-2010, 06:08 AM	#181
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871	Originally posted by cbaytan As an uneducated user I sharpened other picture from Nikon HR page, with Photoshop. Amount 200 % Radius 0.5 Pixels Threshold: 50 Levels Check with the Jackson's cape! Just sharpen properly. But I admit, unlike the test chart sample, the bill sample with AA filter isn't perfectly focussed. I had to sharpen more (FocusMagic r=2 sharpening -- both samples, the test chart (r=1) and the bill (r=2) used the sharpening parameter computed by FocusMagic). P.S. From the fact that you call for a weak AA filter and uneducated users do as well you cannot logically deduce that I called you uneducated Actually, I did not. Last edited by falconeye; 06-15-2011 at 05:29 AM.

06-10-2010, 06:22 AM	#182
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by wll If the new sensor is 21 MP, in the aps-c mode how many pixels would you have ? ~8.8 MP. Just divide 21 by the square of the crop factor (= ratio between the sensor areas). Originally posted by falconeye BTW, you can order the 645D with or without an AA filter. So, there is no Pentax decision I could disapprove. Interesting, I didn't know that. Thanks for the rest of your post as well! Originally posted by falconeye From the fact that you call for a weak AA filter and uneducated users do as well you cannot logically deduce that I called you uneducated Actually, I did not. From the fact that cbaytan wrote "As an uneducated user" you cannot deduce that he thinks that you called him uneducated.

06-10-2010, 06:36 AM	#183
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871	Originally posted by Class A From the fact that cbaytan wrote "As an uneducated user" you cannot deduce that he thinks that you called him uneducated. And you cannot deduce I assumed he thought But to be honest, I didn't think that cbaytan is uneducated. But I do think as well that very few educated opinions about the AA vs. no AA topic have ever been posted And this Nikon D200HR site is a particularly bad example which tries to mislead on purpose (tries to sell something you don't need).

06-10-2010, 06:56 AM	#184
cbaytan Inactive Account Join Date: Nov 2008 Location: Trabzon/Turkey Photos: Gallery Posts: 1,010	Originally posted by falconeye But I do think as well that very few educated opinions about the AA vs. no AA topic have ever been posted AA filter education? I don't buy and test cameras with and without AA. Most people are trying to learn by discussing here and there, on the internet, like me.

06-10-2010, 07:23 AM	#186
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by falconeye And you cannot deduce I assumed he thought Did you think I thought you assumed he thought?

06-10-2010, 07:48 AM	#187
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,694	"Perhaps it is relatively safe to do with the old MF glass? Leica should be in more trouble with their glass but seem to get away with it." In my experience I find that lens sharpness has little to do with the appearance of moire, pixel pitch seems to be the biggest contributing factor. "Just look at a frame from a 1536x1024 K-7 video." the video from the k-7 is not super sampled therefore aliasing artefacts are going to be much more common with subsampled video output....besides video is a feature on the K-7 that I could live without, though live view certainly does come in handy. "Demosaicing algorithm. It is much more challenging to write a good demosaicer for a weak AA filter. But progress has been made in this domain and e.g. Leica and Hasselblad claim to recognize and eliminate color aliasing in their firmware demosaicers. Pentax does not claim so." though considering how often pentax announces such features, I wouldn't be surprised if they have developed such a thing. at any rate I have explored techniques to combat moire both in camera and on the subject. capture one has a very good moire reduction tool, I am uncertain if Light room 3 has similar functionality but C1 does a very good job of it, despite their less than stellar DNG profiles. one of the simplest ways to prevent moire is to stop a lens down to the point where such fine details are blurred from diffraction. Either that, or ask your models to avoid wearing certain fabrics. "Canon EF-S lenses cannot be used on the 24x36mm cameras, because their rear-element design would "interfere" (i.e. collide) with the mirror. I believe they cannot even be mounted on these cameras." you're correct on that point, though i wouldn't be surprised of Canon alters their lens mount...again, to enable EF-S lenses. " you can order the 645D with or without an AA filter." gee thanks Falk, now I'm going to have to order two of the blasted things... Last edited by Digitalis; 06-10-2010 at 08:06 AM.

06-10-2010, 08:41 AM	#188
ogl Banned Join Date: Dec 2007 Location: Sankt Peterburg Photos: Gallery \| Albums Posts: 8,382	Originally posted by falconeye Just sharpen properly. B P.S. From the fact that you call for a weak AA filter and uneducated users do as well you cannot logically deduce that I called you uneducated Actually, I did not. D200 never had strong AA filter.

06-10-2010, 08:42 AM	#189
ogl Banned Join Date: Dec 2007 Location: Sankt Peterburg Photos: Gallery \| Albums Posts: 8,382	Originally posted by gazonk That's the only drawback I've noticed with my DA70, it so easily outresolves the K10D sensor that I get super ugly color moiré way too often - often combined with labyrinths: Change RAW-convertor.

06-10-2010, 09:14 AM	#190
falconeye Veteran Member Join Date: Jan 2008 Location: Munich, Alps, Germany Photos: Gallery Posts: 6,871	Originally posted by Digitalis "Just look at a frame from a 1536x1024 K-7 video." the video from the k-7 is not super sampled therefore aliasing artefacts are going to be much more common with subsampled video output That was my point. Subsampled video frames are a nice demonstration how images look if you have no means of blurring prior to demosaicing ... no lens blur, no motion blur, no defocus blur and no AA blur. Ugly enough to make people cry for a means to blur ...

06-10-2010, 12:35 PM	#191
gazonk Pentaxian Join Date: Feb 2009 Location: Oslo area, Norway Photos: Gallery \| Albums Posts: 3,746	Originally posted by ogl Change RAW-convertor. The image I showed was converted with PPL, which usually is better at this than Apple built-in RAW which I usually use. But in this case they were similar.

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06-10-2010, 03:32 PM	#192
zackspeed Veteran Member Join Date: Mar 2010 Posts: 527	Originally posted by Pentaxor and the 645D does make economic sense for Hoya? :ugh: Oh yes,it does. The first production Run is complete ordered and sold out

06-10-2010, 03:52 PM	#193
Pentaxor Veteran Member Join Date: May 2009 Location: Vancouver, B.C. Photos: Gallery Posts: 6,513	Originally posted by zackspeed Oh yes,it does. The first production Run is complete ordered and sold out you have to consider which target market is that. otherwise, I dont think that Pentax would make more 645D's than their midrange and starter cameras. same principle as to selling 1D's and D3's.

06-10-2010, 04:04 PM	#194
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by Digitalis In my experience I find that lens sharpness has little to do with the appearance of moire, pixel pitch seems to be the biggest contributing factor. I have a benchmark image, the roof of a house in the distance. Only a few select lenses of mine excite moiré with this roof. The majority doesn't. Originally posted by zackspeed The first production Run is complete ordered and sold out Nice to hear! Thanks for sharing.

06-10-2010, 05:57 PM	#195
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,694	"I have a benchmark image, the roof of a house in the distance. Only a few select lenses of mine excite moiré with this roof. The majority doesn't." lens micro contrast, is what is to blame here...remember film? the reason why moire never occurred with film is due to the random nature of silver particles, not to mention the fact that resolution of High spatial frequencies would reach it's peak and sharply lose contrast beyond that point, We never had aliasing artefacts like we do with digital. Moire is a sensor based artefact, I won't debate if certain lenses exacerbate it or not, I'm sure some do due to higher contrast at higher frequencies.