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Sigma SD-1 42mpx


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<blockquote>

<p>Jeff, how do you calculate the Bayer sensor's output? Which Sigma bodies do you use?</p>

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<p>I'm not sure what you mean by output. For resolution, I multiply X and Y, then divide by one million. My old 5D, for example, produces images that are 4368 pixels by 2912 pixels which yields a total pixel count of 12,719,616 pixels or 12.719 MP.</p>

<p>Using the same methodology, <a href="http://www.ddisoftware.com/sd14-5d/flower.jpg">this image</a>, taken with a Sigma SD14 "14 megapixel" DSLR measures 2640 pixels by 1760 pixels for a total pixel count of 4,646,400 or 4.646 MP.</p>

<p>There are advantages and disadvantages to both sensor architectures, I'm not denying that. I have never used a Sigma body and didn't mean to imply that I had.</p>

<p>Regarding video, modern display, Live View...</p>

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<p>It's news to me that these are necessary in a camera.</p>

 

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<p>They are not necessary. However, if you wish to compete with your peers (Canon and Nikon) it's sort of important that you provide similar offerings, no? This leads me back to my original statement, if it offers an extraordinary photographic experience then it <em>may</em> be worth more than DOUBLE the Canon 60D which has an 18MP sensor, 1,040,000 dot display, Live View and HD video.</p>

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<p>By output I meant whatever metrics you're using to judge both sensors. <br /> <br />How do you compete with peers when you have a Foveon sensor? There are the people who always downplay Sigma for using marketing ploys and funky math without ever having tried it. I'm not saying Sigma is the new Messiah, but you have to admit that their sensor technology is something that no one else has. Yeah, the high ISO noise is an issue for me but I like the camera and the images I get with it. Hopefully the SD1 will help Sigma open more minds out there, I just hope they bring the price down more.</p>

<p>For both sides of the argument though: Loyalty is the trait of refusing to admit you've made the wrong decision. ;)</p>

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<p>I think Sigma is about 2 years behind the times. If they threw in HD video, live view, IS, and a 930,000 px disp. it would be a maybe.</p>

<p>Well if their are behind by a few years so be it but who the heck felt we needed Video in our DSLR to<br>

begin with and other things, I can see where live view in the Studio would be a great help, But since the most of the Sigma lenses are now being shipped with OS so they do not need it in the camera:</p>

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  • 4 weeks later...
<p>Jeff, you need to do a little research, so you understand that 15 million photosite locations does not equal fifteen million pixels. Imagine if each of the pixels in a Canon 7 D (which is supposed to be 18 MP) could capture the true color of the light hitting it? Imagine if ALL of the light hitting a sensor could be used, rather than 2/3 of it being "filtered" out. In fact, if you are shooting a photo of something red or blue with a "normal" sensor, you are only capturing light on about 1/4 of the surface of the sensor. With the Foveon sensor you are capturing light over the entire sensor's surface. Now you understand a little more about Foveon technology.</p>
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<p>Jeff, are Canon and Nikon really considered peers to Sigma? I believe Sigma is positioning themselves in a class similar to the Leica S2, which does not do video and does not have in-camera image stabilization (anti-shake), and costs WAY more than the "competition" presented by their so-called peers. Really the S2 is a peerless camera (and lens system). I believe the Sigma cameras are peerless too. The Foveon sensor is in a class of its own, just as the larger-than-full-frame sensor in the Leica is and the hex sensor in the Fuji cameras was (which has unfortunately experienced its last SLR iteration in the now discontinued S5, but has now found its way into the very expensive Fuji retro point & shoot). This new Sigma will produce images better than any other APS-C sensor camera and possibly better than just about any other camera under $5,000. It will probably cost less than half that though. That makes it an amazing performer, though not a featur-packed one (similar to Leica and Hasselblad cameras, though they do have weird and wonderful features that other cameras do no have).<br>

-<br>

The performance of the new Sigma will dictate its desirability, but I suspect the many happy foveon users out there will upgrade to this new beastie. Certainly this camera will get attention from the quality-minded crowd. I will finally buy my first Foveon sensor camera, now that Sigma has fixed the issues that I had problems with when their flagship was in its SD14 iteration. I just wish they had the SD15 available, when I was deciding to buy my Canon EOS 5 D. I would have definitely bought it, since I consider it to be a superior camera to the 5 D.<br>

-<br>

Now, unfortunately, I am looking for a camera with a swivel screen, and I believe I've found what I want in the Sony A55. I will probably buy and use that with a couple of Sigma lenses until I have the opportunity to buy the new Sigma camera, and then I will probably use the new Sigma for general Landscape photography, so I will most likely mount a Sigma 18-50 on it to start with.<br>

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These inexpensive Sigma lenses are the ones I see myself getting for use with this camera:<br>

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http://www.bhphotovideo.com/c/product/622376-REG/Sigma_861110_18_50mm_f_2_8_4_5_DC_OS.html<br>

http://www.bhphotovideo.com/c/product/622387-USA/Sigma_686110_50_200mm_f_4_5_6_DC_OS.html<br>

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Why? Because they are both OS and HSM. The shorter one has a small range and f2.8 aperture at the bottom end, so it will be a good performer for the money, and the long one has a 4x zoom range and fits well with the 18-50. It will be a good performer for my model shoots aw well as a reasonable performer for shooting animals and other creatures, since it gives a 1:4.5 magnification. I shoot at f5.6 and f8 most of the time, when I'm not shooting at f11. This means that for most of my shots these lenses will perform at about the same quality as more expensive lenses. I will also be buying a couple of expensive fixed focal length lenses in the future, when I can afford to, after dishing out the big bucks for the new Sigma body. The added expense of the big-aperture lenses will allow me to shoot those rare wide-aperture photos on the beach at dusk and in other dark environments, such as the woods (where I shoot models from time to time).<br>

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A fixed focal length lens is the best for such scenes, but normally I shoot at slower shutter speeds, to avoid noise or short depth-of-field, which I've found to be a problem when shooting models. Lately though, I've been realizing I need that super wide aperture to focus properly, something I even had trouble with when using my Canon 5 D with my Canon 50mm f1.4 lens one time in a very dark forest with a model. Unfortunately, none of those photos turned out very good. I should have used a tripod and a flash-light. It would have been nice to have in-camera image stabilization for that scene too.<br>

-<br>

- Yes, I wish the new Sigma would have in-camera image stabilization (one of the advantages of Sony cameras).<br>

- Yes, it would be nice if the new Sigma would allow me to use CF Type II cards too, because I use Micro-SD cards (so I can read my cards with a variety of card readers and avoid obsolescence), and my SDHC adapter requires a type II card slot. I guess I'll have to get a different adapter.<br>

- Yes, I wish the new Sigma would have two card slots that would record duplicates simultaneously for mission-critical reliability and give me the ability to copy files from one card to the other, for duplication of material without the need for accessories.<br>

- Yes, I wish the new Sigma would have a useful live-view function (and a fold-out screen), so I can mount my camera on a tripod and focus on flowers and such using a 5x or 10x magnification in live-view mode for shooting macro stuff.<br>

- Yes, I wish the new Sigma would have built-in wireless N networking and BlueTooth with wireless accessories, like a BlueTooth radio remote controller, a BlueTooth wireless flash controller, etc. It would be nice to be able to transfer preview images to my notebook computer or even a big screen desktop computer through my wireless network for instant review on a screen bigger and better than the little 3 and 3.5 inch review screens available on cameras. I met a photographer who uses his iPad for this exact process, and it looked like he was loving the ability to do that. It made me wish I could do that.<br>

- Yes, I wish . . . I wish.<br>

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Wishes only come true some times. Maybe Sigma will read this and include such features in their professional level Full-frame Foveon sensor body, when it comes out for $3,000 or $5,000 some time next year (hopefully). Wouldn't that be wonderful?!?<br>

-<br>

And wouldn't it be wonderful for Photo.net to finally start a Sigma forum, like they did for Sony? I mean Sigma produces a LOT of lenses, and now they seem like they're about to have two SLR cameras on the market simultaneously. Isn't it about time? (Yes, I know they can't have a forum for EVERY camera and lens maker, such as Fuji, Tamron, Tokina, Vivitar, Casio, Phoenix, Bower, etc., etc.)</p>

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  • 5 months later...

<p>There has been some discussion of equivalent megapixel ratings of foveon vs. bayer sensors. Here are the facts. When you consider the maximum resolution, defined in terms of error free reconstruction of an image, it is limited by the Nyquist sampling theorem. In terms of this a 46 megapixel foveon sensor is equivalent to 15.3 megapixel.</p>

<p>How does that compare to a Bayer sensor? The green channel of a 25 megapixel bayer sensor is actually equivalent to only a 12.5 megapixel sensor, and the blue and red channels are equivalent to only 6.25 megapixel sensors each. The overall result (considering the three color channels together) is somewhat less than 12.5 megapixels of equivalent resolution, mainly because the blue and red channels do not measure up to the green channel.</p>

<p>Thus, the vendors of neither bayer or foveon sensors are being truthful in their ratings. However, if you want to use a rule of thumb you can take Sigma's advertised number and multiply by 0.67 to get the equivalent number advertised for bayer sensor. Thus, sigma's "46 megapixel" camera has a resolution roughly equivalent to bayer sensor advertised as "30 megapixel".</p>

<p>Let me say something about interpolation. There is a lot of misunderstanding about this issue. Bayer sensors use interpolation to upsample to give an apparently higher number of pixels in their output files. These pixels do not increase true resolution, which already has a hard limit determined by the Nyquist sampling theorem. Any resolution added by interpolation is fake, being at best an educated guess which might, if one is lucky, work for some images but does not work for others.</p>

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