How many usable megapixels will go on a full-frame sensor?

<p>If the Canon 7D and the T2i can pack eighteen megapixels of truly usable data onto a cropped sensor, then how much is possible on full frame sensor? Will the 1Ds Mark IV (or whatever it is called) be capable of over forty megapixels that are of high quality?</p>

<p>One thing that we have seen is that not only the number of megapixels has been increasing over the years, but the in-camera processing has been improving as well.</p>

<p>I wonder what the theoretical limits are. </p>

<p>More to the point, what are the practical limitations on how many megapixels one can profitably put on a full-frame sensor?</p>

<p>--Lannie</p>

<p>Great question, Lannie. I'm not sure, though, that you're going to get an unequivocal answer.</p>

<p>I'm not convinced that the 7D and T2i have 18 MP of "truly usable data" -- or at least, I'm not convinced that overall performance (taking noise levels into account) would not have been better at 12-15 MP.</p>

<p>Compare the 5D Mark II to the Nikon D700. Both full-frame, but the 5D2 has 21 MP while the D700 has only 12 MP. Unquestionably the Canon has higher spatial resolution; also unquestionably, the Nikon has less noise.</p>

<p>At this point the technology has reached the point that we have enough resolution to be really useful, as opposed to the 4-6 MP DSLRs of several years ago. Now I would like to see the manufacturers focus on increasing the dynamic range of their sensors rather than chasing spatial resolution endlessly (Canon) or making them able to shoot in the dark (Nikon). In other words, I want a digital camera that can deal with high-contrast scenes without blowing the bright parts or blacking out the shadows.</p>

<p>I think it would be better to keep the MP count about where it is on the FF sensors. 21MP is fine, but 40MP would be too many. Other than saying, "my sensor has more pixels than yours" what will packing all those pixels do. Right now 21MP is incredible and I don't think there's anything its lacking. Enlargements can be made to huge proportions and still look great. If you pack more pixels, each individual pixel will be smaller and won't collect the light as well or produce as clean of an image. I don't think its a accident that the $4500 1D MkIV has less pixels on a larger sensor than the $1600 7D and $800 T2i. The people that spend the money on a pro camera know that pixel count isn't everything and its the quality of those pixels that affects the end result. So unless Canon can put quad Digic XII processors in a camera to process all those pixels incredibly, I think they'll have a hard time making a 40MP camera that is as clean and sharp and handles noise as beautifully as the 21MP FF cameras available now. If they're going to up the MP count, they should do it in moderation and put more into the processing to keep the high ISO noise levels and cleanliness of the image as good if not better than it already is. I don't really see anything you can't do with the 21MP currently available. And you know what they say, "If it ain't broke, don't fix it."</p>

<p>Just the numbers -</p>

<p>A full-frame sensor with the same pixel pitch as a 7D or T2i would have 46,700,000 pixels.</p>

<p>A full-frame sensor with the same pixel pitch as a G9 would have 240,000,000 pixels.</p>

<p>In previous generations, the 1Ds has had roughly 12% smaller pixel pitch than the 1D. If that trend continues, the 1Ds IV will have around 34,000,000 pixels.</p>

<p>As to what will happen next, who knows? Canon did back off on the pixels in the G series P&S cameras - the G11 has fewer pixels than the G10.</p>

<p>

<p>Well since you did not ask how many pixels should be put but rather how many could be put I would say the number is at least 40MP. Having said that for most uses I really think 6 – 10 MP is really enough. But one thing that we have seen over time is more pixels will often sell a camera, so I am sure we have not seen the limit of pixels on a FF camera yet.</p>

</p>

<p>Moore's law will apply.</p>

<p>As has already been stated, the 18mp on APS-C is already too much for 99% of situations and lenses. You don't get 18mp of truly usable high quality data. <br>

 <br>

Diffraction limits (the common sense limit on pixel numbers) on FF cameras at wide apertures have not been reached yet though, so in some situations with the very top lenses wide open, or close to it, with perfect technique and lighting, theoretically, they can bump just under 40mp. I think they will top out in the studio orientated 1Ds model range in the high 30's. I doubt if the 5D MkIII would have the same sensor this time though.<br>

 <br>

Certainly on newer lenses, like the 100mm IS macro, on FF the Nyquist limits (the 21mp FF theoretical sensor resolution limits) are hit before diffraction limits.</p>

<p>David,</p>

<p>There is no reason to expect Moore's Law to be applied to sensors when practical physical limits are known and understood. Useful pixels are not the same as processing speeds, transistor numbers, or storage space.</p>

<p>After diffraction limits are hit the marketing chaps can just do like cellphones; you upsize it in the camera to give that giant bloated file folks crave; worship; need for bragging rights.</p>

<p>Thus you camera upsizes that plain 25 megapixel FF image to 100 megapixles; and your neighbor who has only "80" feels weak; unmanly; a total failure.</p>

<p>Thus next weekend he shows you his NEW 120 megapixel body FF body and now you feel weak and a failure!</p>

<p>What really matters is that big "ABC" megapixel number for bragging rights!:)</p>

<p>Now you are really feeling small. Your mower is only 18 HP and the guys on the right and left has 20 and 22HP.</p>

<p>You were king of the hill with your 100 megapixel FF camera; but the guy on right now has 120.</p>

<p>MP have not, in fact, been doubling every 18 months as one might expect if Moore's Law were the governing principle. Nikon and Canon had 3-4 MP DSLRs ten years ago -- six generations or so in Moore's Law terms. Conservatively, then, we ought to have 192 MP DSLRs today.</p>

<p>I wonder what would happen if you put the processing capability of the 7D in the 5DII ?</p>

<p>Mike, they both use the same processor - Digic 4. Though for all I know they may operate the chip at different speeds.</p>

<p>The 7D does have substantially higher pixel throughput at max frames-per-second (143 Mpixels/sec for 7D, 82 Mpixels/sec for 5D2), but it's not clear if the 5D2 is limited by mechanical limits of the mirror box or by the processor - or by a marketing decision to intentionally keep the max fps of the 5D series below that of the 1Ds.</p>

<p>The 1D4 has only slightly higher pixel throughput than the 7D - 160 Mpixels/sec. Despite this the 1D4 uses 2 Digic 4 processors. Which implies that the 7D is operating right at the limit of that chip's capability.</p>

<p>7D has Dual Digic IV.</p>

<blockquote>

<p>7D has Dual Digic IV.</p>

</blockquote>

<p>So it does. I had mis-remembered.</p>

<p>Well then, putting dual Digic 4 in a 5D2 could presumably double the max fps, to about 8.</p>

<blockquote>

<p><em>Great question, Lannie. I'm not sure, though, that you're going to get an unequivocal answer.</em></p>

</blockquote>

<p>That's for sure! Sufficient prior claims have been made about the limits of photosite density, that it would be wise to remain skeptical about those made today.</p>

<p>Even the "lenses can't resolve the detail" arguments are not necessarily the final word, since there is some notion that there would still be value if smoother gradients from photosite densities higher than those needed for a given lens resolution. (Also, keep in mind that image elements do not, ahem, always line up in perfect vertical and horizontal formation or align perfectly with individual photosites.)</p>

<p>It is complex.</p>

<p>In the end, I wonder how the answer even matters to us, even those of us who actually make rather large prints. As some point, moving to a larger format makes more sense if maximum print size is the goal.</p>

<p>Dan</p>

<p>I know my camera MP increases faster than my computer processing power. I recall processing 10D 6MP RAW on my old G4 duel and they ripped on that ancient 1.25GHz twin. My 5DII raw at 21MP process much slower on my much faster Mac Pro (quad 2.66 GHz Intel Xeon "Nehalem"). I can't imagine needing more MP but then I don't do billboards or sides of buses. I max out at 24x36 prints.</p>

<p>Somehow I am reminded of the reason why the pdp-11 mini computer was designed with 64K memory... because no one would ever want more...</p>

<p>... which in turn reminds me of why MS-DOS only allowed 640k of memory for user applications... because no one would ever want more...</p>

<p>... which reminds me of why some of the super mini computers were designed with 4G memory limits, because no one would ever want more...</p>

<p>... which then reminds me of... well you get the picture don't you?</p>

<p>Could there somehow be an analogy made to digital photography here?</p>

<blockquote>

<p>Mike, they both use the same processor - Digic 4. Though for all I know they may operate the chip at different speeds.<br>

The 7D does have substantially higher pixel throughput at max frames-per-second (143 Mpixels/sec for 7D, 82 Mpixels/sec for 5D2), but it's not clear if the 5D2 is limited by mechanical limits of the mirror box or by the processor - or by a marketing decision to intentionally keep the max fps of the 5D series below that of the 1Ds.</p>

</blockquote>

<p>The processor itself was not the only part of my thinking - in technology, you never only improve one aspect. For instance if you want to buy a faster photocopier you can't get only that - you have to buy one that is not only faster but one also has a zillion other additional functions. In a similar way, I doubt the 7D has only a faster Dual Digic processor - between releases dates of the 5DII and 7D there must also be improvements in programming to cope with the higher pixel density (for instance better noise reduction, better 'image creation' from the information in the pixes .<br>

To take it one stage further, if they put the programming into a recent body such as the 40D/50D, how good could they be?</p>

<p>Alan, it's a weak analogy because photography has practical limits that computers lack. We really don't need more sharpness than the eye can see, and we rarely need to enlarge beyond a comfortable wall-hanging size. Most photographs by non-professionals are never printed at all, just viewed on a digital display that has vastly less resolution than current cameras.</p>

<p>Computer power, on the other hand, is always in need because as soon as someone comes up with a faster computer with more memory, someone else comes up with software that pushes the new computer to its limits, or the users want to run more and more programs simultaneously. Now that powerful dedicated graphics processors are common, operating systems like Windows and MacOS take advantage of them to provide elaborate eye candy that wouldn't have been practical on typical personal computers ten years ago. We've even reached the point where a fast computer is often used to simulate several computers all running in parallel.</p>

<blockquote>

<p>Could there somehow be an analogy made to digital photography here?</p>

</blockquote>

<p>And Kodak revamped their film to be of even finer grain. That's the best I can do.</p>

<p>I'm all for pushing technology. Some of the stuff I don't like; such as putting video capabilities in a still camera. I'd rather they put more money into the glass or sensor then adding crappy video capabilities - I'll get over it.</p>

<p>A 46MP DSLR? Hell yeah! More dynamic range? Hell yeah! Even if I don't ever buy that camera, the tech will trickle down and the cameras that I can afford will have the capabilities that match today's top DSLRs and then some.</p>

<p>Pushing technology opens up creative avenues. And it's not just MPs or range its also form factor. I really love this new trend in smaller compact cameras with the sensors of DSLRs: Olympus PEN, Lumix, Samsung, Sigma SP2, Sony NEX and who knows what's coming out.</p>

<p><em>Photography has grown stagnate and boring.</em><br>

This new technology will bring things that we've never seen before and I can't wait. Whenever there's new technology - photography just goes into new directions and great things are done. It happened when silver photography was invented, then roll film, then the SLR, and now with digital and the subsequent tech. I think as the kids use this stuff they're going to do things that we've never would have even thought of. And I say, give the tech - 46MP sensors, 20 stops of range, video, 3D .....</p>

<p>let's see my first computer had 4K of RAM, I now have 2GB, my digial in 1999 had 1.2 Mb, so in 2032 digital camera should have 600 GPixels. Now since we are talking about a FF 35mm sensor that is going to get a bit tight, figure about 0.038 microns pixels. I would say dropping the pixels size below the wave length of light would not make much sense. So lets say we limit the pixel size to 0.5 microns, then we end up with only 3.45 GPixels. I have to tell you that once you get past 1 GPixel it gets pretty silly, IMO. </p>

<p>If Canon does produce a new camera in the 40 MP range or higher, imagine the implications/rquirements for lens technology.</p>

<p>How many existing L series lenses would be found to be adequate for resolving all those megapixels?</p>

<p>--Lannie</p>

<p>Here is a crop from a hand-held shot using the 5D II made several weeks ago:</p>

<p>http://www.photo.net/photo/11041000&size=lg</p>

<p>As we start thinking in terms of doubling the number of megapixels in the 5D II, the implications as to what might be possible really are astonishing.</p>

<p>--Lannie</p>

<p>I find my 50mm f/1.8 lens does fairly well at using the 15MP of my 50D. So figure the 1.6 crop factor and the same size pixels on a FF camera would come out to 38.4 MP.<br>

Here is a frame using the 50D<br>

<a title="IMG_2258 by KonaScott, on Flickr" href=" src="http://farm5.static.flickr.com/4143/4755746633_826b54a540.jpg" alt="IMG_2258" width="333" height="500" /></a><br>

A 100% crop from the above image</p>

<p><a title="100 percent crop from 50D by KonaScott, on Flickr" href=" src="http://farm5.static.flickr.com/4140/4756384806_0ddfa494eb_o.jpg" alt="100 percent crop from 50D" width="700" height="700" /></a><br>

I use the 50mm a fair bit when stitching, which in the case lets me get an idea of how this might look for a FF camera, here is the part of the stitched image that would cover the same area as a FF camera.<br>

<a title="50mm lens FF sized by KonaScott, on Flickr" href=" src="http://farm5.static.flickr.com/4099/4756388144_edb9e56cd4.jpg" alt="50mm lens FF sized" width="500" height="333" /></a><br>

And here is the full image<br>

<a href="http://farm5.static.flickr.com/4099/4756388144_5053f131c7_o.jpg">link to 38.4 MP image</a><br>

It really does not take L glass to make use of a lot higher resolution then 21MP on a FF camera. Having said that, how often do you really need more then 21 MP?</p>