February 27, 2015, 07:02:12 AM

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Messages - torger

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1
EOS Bodies - For Stills / Re: DP Review of New Canon 5Ds
« on: February 06, 2015, 03:33:56 AM »
I suspect that Sony has some key patents that makes it extremely difficult for any other player to compete on DR.
Basically every other player IS competing on tttmnbso*, except Canon. Toshiba? Over 13 stops. Samsung? Over 13 stops. Aptina? They have sensor tech that can do a whopping 20 stops! Canon? Over 11 stops.

Uhh... good point :)... I had forgot about those, but you're right, Canon really is behind and in light of that it's even more of a mystery.

2
EOS Bodies / Re: Canon EOS 5Ds and EOS 5Ds R Preview
« on: February 06, 2015, 03:20:59 AM »
I don't think the DR thing is ignorance from Canon, I'm guessing Sony holds some pretty important patents and without them it's very hard to compete. Canon simply can't do it, if they could they would.

The noise quality will make a big difference though, if the noise is nicely random and lacks banding or any other pattern issues then it will appear to have much more DR than say my aging 5Dmk2 even if they measure similarly.

3
EOS Bodies - For Stills / Re: DP Review of New Canon 5Ds
« on: February 06, 2015, 02:54:09 AM »
What surprises me is why Canon waited this long to make a high MP camera if they couldn't compete on DR anyway. They could have released a 30-something camera when Nikon D800 took off.

I suspect that Sony has some key patents that makes it extremely difficult for any other player to compete on DR.

4
EOS Bodies - For Stills / Re: DP Review of New Canon 5Ds
« on: February 06, 2015, 02:51:50 AM »
So, who all are moving over to Nikon / Sony?

In a way I'm a bit pleased that DR is not progressing. In addition to my Canon I'm using this old-school medium format camera, and it's nice to see that it's still not obsolete ;). Quite remarkable that an MFD CCD from 2004 (mine is from 2008) has slightly better DR than a Canon camera from 2015.

Canon is still great at higher ISOs, so I see no reason to switch. I won't be all over this camera though, although I'll probably rent one to try out the resolving power on the lenses I got.

5
EOS Bodies - For Stills / Re: DP Review of New Canon 5Ds
« on: February 06, 2015, 01:43:55 AM »
It answered the main question I had -- have they fixed the DR issue, and the answer is --- no. Well, that's going to disappoint people.

6
EOS Bodies / Re: More Images of the Canon EOS 5DS & 5DS R
« on: February 05, 2015, 06:37:54 AM »
Camera companies (except Sony?) are extremely conservative when it comes to changing camera operation and design for a good reason. When you use a camera a lot you start to get reflexes, and you would not be happy if buttons would move around between models. This is especially important to professional photographers that use it as a tool rather than seeing at as the latest trendy electronics thingy.

7
EOS Bodies / Re: POLL: aa, or not to aa (5ds vs. 5dsr) ?
« on: February 02, 2015, 03:20:18 AM »
Here's an example of false colors in an irregular landscape subject, the magenta and cyan pixels are not there in reality:

http://www.ludd.ltu.se/~torger/photography/img/ltr-colormoire.jpg

this requires the lens to be very sharp of course, and results vary depending on demosaicers. In general the demosiacers producing the finest details get more problems with false colors. Lightroom makes more false colors than Phase One's Capture One for example.

Water is another landscape classic where moire/false colors can show:

http://echophoto.dnsalias.net/ekr/Articles/Aliasing2/seawater_a.png

So there's more than fabrics.

When you shoot winter subjects it can be visible around sharp edges, thin tree branches on a white background for example.

The examples I've seen from the D800E when it doesn't produce any aliasing always show a pretty soft lens or much stopped down...

8
EOS Bodies / Re: POLL: aa, or not to aa (5ds vs. 5dsr) ?
« on: February 02, 2015, 02:31:18 AM »
Being a contributor to RawTherapee I know a thing or two about demosaicing, and sensors without AA filters is not making it easier. You will get false details and colors, when you know what happens on the software level and how much errors there is in the final image it's much harder to think AA-free cameras is a good idea than if you don't know...

However a little disclaimer - my experience comes mainly from medium format where lenses are sharper and microlenses are either not there or are less effective. It may happen that thanks to softer lenses and better coverage of the microlenses combined with a landscape aperture at f/11 the false color issue is so much reduced it will be negligible to some. If you're the unsure kind I'd wait and see how it looks.

9
EOS Bodies / Re: POLL: aa, or not to aa (5ds vs. 5dsr) ?
« on: February 02, 2015, 02:04:03 AM »
I shoot medium format were there you can't get a camera with AA filter. It's a pain. People has come to believe that being without low pass filter is a feature, but believe me it's not. It's a bad idea, anyone remotely familiar with signal processing knows it.

People think it's only about moire, but the main problem (unless you shoot fabrics) is actually false colors around small details. I rather have a correct smooth image than an aliased image riddled with false colors. With small apertures you can compensate some, but with the Canon you'd need f/11 or even f/16 to really kill aliasing. Yes you can live with it in landscape as you shoot with small apertures and false colors is in that case only obvious to the trained eye (moving water can be a big issue though), but it's just so unnecessary when there is an alternative.

And really at 50 megapixel you need that tiny bit of extra sharpness? False colors is a real image quality issue, while slight softening at 50 megapixel resolution is not, especially when you make a print. Being without AA filter is only a pixel peep thing. AA filters sharpen up well, as it's the same smoothness over the whole image surface. You have a problem with sharpness if the lens does not perform and delivers uneven sharpness over the surface, but that's a different story.

Here's one example article showing the effects of moire and false colors:

http://echophoto.dnsalias.net/ekr/index.php/photoarticles/78-aliasing-and-supersampling-why-small-pixels-are-good

10
EOS Bodies / Re: Colou
« on: January 30, 2015, 09:31:26 AM »
Can't wait to see sample images and sensitivity comparisons...

Actually NO! The trend with MF is to optimize the ISO availability ;-)

A plea to the more knowledgeable people here:
Could you please enlighten me why Canon is going for colour that actually eye perception is UNABLE to differentiate? Or I misunderstood it?

You can read this about the Phase One IQ250

http://www.luminous-landscape.com/essays/the_phase_one_iq250_cmos_fully_realized.shtml

quoting the section on the CFA:

"As one example, the selection of a CFA, the color pattern put in front of the sensor, is a choice between quality of color, and ISO performance. If the CFA allows each pixel to see a broader spectrum of color (e.g. for the green pixels to see a bit further into yellow) a camera’s ISO range can be modestly increased. The resulting loss in color quality is subtle – subtle variations in color are missed and a handful of specific colors become difficult to photograph. In a market where a ISO 25,600 camera has a leg up on a ISO12,800 camera, the engineers are under enormous pressure to pick the modestly increased ISO over subtle color quality."

The trend of going to more ISO in MF is because CMOS has become available just recently. The olde CCD tech was just not capable. Still The IQ250 is capped at ISO6400.

Stay at MF-oriented forums for a while. Color is a big thing there. What's real and what's imagined differences is harder to understand, but even microscopic differences are important to that kind of users. So if you want to get good credibility in those circles this kind of optimization, regardless of how subtle it is, is valuable.

11
EOS Bodies / Re: More About the EOS 5DS & EOS 5DS R
« on: January 30, 2015, 09:18:49 AM »
Not once have I read someone complain about colour accuracy when shooting birds or sport.

No, it's a medium format thing, on medium format forums these kind of very subtle and subjective color issues are discussed at length.

I can guarantee that it's a very small difference in the CFA, and it does not limit high ISO that much. Capping it at ISO6400 is probably more about differntiating their own products than that the sensor is really limited. It could be that the real fact is that they aim this camera to be a studio/landscape/architecture camera and people that care about utmost image quality and color and then you don't use high ISO much, and that fact has been transformed to this type of rumor.

Pentax 645z is a MF camera that is said to have CFA optimised for color accuracy and it also happens to have ISO 204800

12
EOS Bodies / Re: More About the EOS 5DS & EOS 5DS R
« on: January 30, 2015, 09:00:46 AM »
That's really interesting. A claimed advantage of medium format digital cameras have been that they have color-optimized CFAs rather than high ISO, it would be awesome if this sensor has taken the same type of optimization.

I think a 50 megapixel camera for sure should be optimized at high resolution use cases, rather than trying to be a hand-held low light action camera.

13
EOS Bodies / Re: Bingo! New Canon 5Ds has 50.6 MP new rumored specs
« on: January 30, 2015, 08:54:17 AM »
On the topic "which version to get" that is with or without AA filter, it will depend if you care about pixel peep crispness or real image quality. AA filter is a good idea, sure it will reduce crispness but also take away most false colors and aliasing, and moire. Diffraction won't kill aliasing fully until you're up at f/16, so yes AA filter is the way to go.

But what will happen of course is that people will prefer pixel peep crispness over aliasing, jaggies, moire (because most don't really know about these issues or choose to ignore them) and buy the 5DsR and the next high res camera will only exist without AA filter, that was the case with the D800 and I think the same will happen here.

14
EOS Bodies / Re: Big Announcements Coming Next Week [CR3]
« on: January 30, 2015, 06:09:28 AM »
It's supposed to be a medium format killer, don't you think? In that case ISO6400 is plenty. Still seems as an unlikely upper limit coming from Canon, but maybe they want to sell the lower megapixel cameras for high ISO work.

15
EOS Bodies / Re: A Sony & Canon Sensor Partnership Mentioned Again [CR1]
« on: January 29, 2015, 09:37:04 AM »
One thing is sure, a high megapixel Canon body with the same DR as previous Canon models would be a massive disappointment. To make the consumers happy it must be competitive with Sony in this regard.

If the only way they can achieve this is to use a Sony sensor, then it's the right way to go.

If it falls a little short on high ISO performance compared to their other models it's just a plus, it differentiates the products, it's not good to have one that is best at all aspects. Today a high resolution camera must perform excellently at base ISO with huge DR, that's what people expect.

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