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Digital Photo Newsletter Vol 15, No 4Date: February 22nd 2013 To subscribe, unsubscribe or change your email address, visit: ===================================================== ---------------------------------------------------------------------------------- Welcome to the 352nd edition of The Imaging Resource Newsletter. This issue, we explore the bizarre history of why the photographic film industry knew about the U.S. Government's secret atomic tests while the general public was kept in the dark, share an excerpt of our just published Shooter's Report on the groundbreaking Sony RX1 and much more. TOPICS SPONSORS This issue is sponsored in part by the following company. Please show your appreciation by visiting the link below. * Sigma * At the new Sigma, photography is our one and only focus. -------------------------------------------------------------------------------------------------------------------------------------------- Are you in the digital photo business? This newsletter is read by approximately 55,000 combined direct and pass-along subscribers, all with a passion for digital photography. For information on how you can reach them, contact us at editor@imaging-resource.com. -------------------------------------------------------------------------------------------------------------------------------------------- FEATURE: Not-so-secret U.S. atomic bomb testing -- Why the photographic film industry knew what the public didn't By Tim Barribeau (Published first for IR Newsletter subscribers.) It's one of the dark marks of the U.S. Government in the 20th century ��a complete willingness to expose unwitting citizens to dangerous substances in the name of scientific advancement. It happened with the Tuskegee syphilis experiment, with the MKUltra mind control project and with the atomic bomb testing of the 1940s and 50s. The Atomic Energy Commission (AEC) knew that dangerous levels of fallout were being pumped into the atmosphere, but didn't bother to tell anyone. Well, anyone except the photographic film industry, that is. Photographic film is particularly radiosensitive -- that's the reason why you see dosimeters made from the stuff, as they can be used to detect gamma, X-ray and beta particles. But in 1946, Kodak customers started complaining about film they had bought coming out fogged. Eastman Kodak investigated, and found something mighty peculiar: the corn husks from Indiana they were using as packing materials were contaminated with the radioactive isotope iodine-131 (I-131). Eastman Kodak at the time had some of the best researchers in the country on its team (the company even had its own nuclear reactor in the 1970s), and they discovered something that was not public knowledge. Those farms in Indiana had been exposed to fallout from the 1945 Trinity Test -- the world's first atmospheric nuclear bom b explosions which issued in the atomic age -- and spewed fallout into the atmosphere. Kodak kept this exposure silent. Some of the facts in the story are -- like the film in question -- a little hazy. Some claim Kodak's discovery happened in 1946, some in 1945. The Trinity Test was officially July of 1945, but I can believe that by the time corn was exposed to the radiation, picked, the husks converted to packing material, used, and then the film sold, it could well have been 1946. But given that the government initially denied that the Trinity Test was even nuclear, instead calling it an "ammunition explosion," perhaps Kodak's silence is more understandable. But the story doesn't end there in 1946, with Kodak keeping a lid on atmospheric nuclear bomb testing by the government. The U.S. continued with atmospheric detonation tests, most famously in the Pacific, but also back on American soil in the 1950s, at the Nevada National Security Site. The first test in Nevada was in January of 1951, and days later, as snow blanketed the city of Rochester, N.Y., Kodak detected spiked radiation levels that measured 25 times the norm, some 1,600 miles away from the test site. To quote current Senator Tom Harkin (D-Iowa) from a Senate hearing held on the subject in 1998: "Kodak complained to the Atomic Energy Commission and that Government agency agreed to give Kodak advanced information on future tests, including 'expected distribution of radioactive material in order to anticipate local contamination.' "In fact, the Government warned the entire photographic industry and provided maps and forecasts of potential contamination. Where, I ask, were the maps for dairy farmers? Where were the warnings to parents of children in these areas? So here we are, Mr. Chairman. The Government protected rolls of film, but not the lives of our kids. There is something wrong with this picture." According to a report by the Institute for Energy and Environmental Research (IEER), there was research to indicate the danger of I-131 affecting the populace via the "milk pathway" as early as 1953, and there was fairly strong evidence by 1955. Yet the tests, continued without warnings to farmers or the population until the early 60s, while providing film manufacturers with "maps and forecasts of potential contamination, as well as expected fallout distributions which enabled them to purchase uncontaminated materials and take other protective measures." -------------------------------------------------------------------------------------------------------------------------------------------- REVIEW: Sony Cyber-shot RX1 (Shooter's Report Excerpt) By Dave Etchells (You can check out our extensive Sony RX1 review, complete with gallery photos, side-by-side image comparisons, lab tests results and our final conclusion, here: http://www.imaging-resource.com/PRODS/sony-rx1/sony-rx1A.HTM - not up yet as we go to press, but should be there either over the weekend, or sometime Monday mid-day.) I love this camera! Let's just get that out of the way at the beginning, so you won't wonder where I'm coming from. I see a lot of cameras in my job as publisher at Imaging Resource, so it takes a bit to get me excited about a new model, but the Sony RX1 simply blew me away from the moment I set eyes on it. If you insist on knowing why, I've written a few thousand words that you can read below, but if you'd like to save the time (and have the money), just go buy one -- you'll almost certainly be glad you did. Great things in a tiny package The first thing that hit me when I saw the Sony RX1 for myself was just how small it is. It's hard to get a sense for this from typical product shots, so I took a couple of photos to help convey a sense of scale. The shots below show it in comparison to an average-sized hand, and beside a current higher-end digicam. These may help a little, but still won't adequately prepare you for the first time you see and hold the RX1 for yourself: It's hard to imagine how Sony's managed to cram a full-frame sensor in there, let alone designed a lens that small that can cover it. The Sony RX1 is literally the size of some larger digicams, yet sports a full 24x36mm, 24 megapixel sensor, and one of the best lenses we've yet seen on a fixed-lens camera. The next thing that struck me when I finally laid hands on the RX1 was the sense of quality it exudes. You'd certainly hope for quality construction in a camera retailing for $2,800, but it's nice to see that expectation met, and it was a joy to experience, after handling hundreds (and hundreds) of lesser cameras built to meet lower price points. The body itself is all metal, the only exceptions being a rubber handgrip, plastic doors for the ports and battery compartment, the cover for the popup flash head, and apparently the LCD cover screen. (More on that last one in a minute; one of my very few gripes about the camera.) Just-right control feel The controls of the Sony RX1 continue the sense of quality, with just the right balance between stiffness and ease of use. This balance is suprisingly subtle and difficult to achieve, at least judging from the number of times we've seen manufacturers have a hard time with it. Get it wrong one way, and control settings can change with the least jostle, bump or errant brush of a pinky. Get it wrong the other way, and you end up with sore fingers after using the camera for a while, and possibly even missed shots because you couldn't get a control to change quickly when you needed it to. It's ultimately a matter of personal preference, but for my part, I found the RX1's controls just about right. The EV-adjust and Mode dials both take enough force to move that it's very unlikely they'll ever get changed inadvertently, but they stop short of being so stiff as to be awkward. (OK, if it were up to me, I'd probably make them just slightly less stiff, but they're really fi ne as they are.) The buttons sprinkled around the camera are equally a good balance between too stiff and too easy, with a nice breakaway feel so you'll know when you've pressed one. Finally, the lens controls remind me of the high-quality, manual-focus lenses of yore, in the smooth and precise way they operate, even though focus control in the RX1 is "fly by wire" -- with no mechanical coupling between the focus ring and the optics themselves. I wish this last were otherwise, but the demands of modern autofocus mean there's just no way a focus ring could be direct-coupled and have the buttery smoothness of old MF lenses without auofocus being unbearably slow and power-hungry. Holding the camera in my hand, the slight lip and frictive surface of the textured rubber grip on the front provided good purchase for my fingers, and the raised thumb ridge on the back worked pretty well too. I think I'd like the thumb ridge slightly thicker (perhaps a millimeter or so), but I nonetheless felt I could get a pretty good grip on the camera. I could certainly snap a shot single-handed, but found myself using a two-handed grip almost all the time: Pretty much all of the controls are on the right side, so you'll find yourself supporting the camera with your left hand while you make adjustments with your right, and of course, you'll use your left hand to make any aperture adjustments anyway. Speaking of aperture adjustments, it was amusing watching myself when I first started shooting with the camera, as I wasn't used to having mechanical aperture and exposure compensation controls available. It was embarrassing to see how long I spent pressing buttons and staring at the LCD in aperture-priority mode, wondering why the heck I couldn't change the aperture with one of the rear control dials. I guess it says something about how much more time I've now spent shooting with digital than I had with film earlier in my life. Once I got over the embarrassment, I quickly came to love the physical EV adjustment dial, but was surprised to find myself wishing for a rear-panel aperture adjustment. The old-style aperture ring feels wonderful, but I actually found it a little awkward having to shift my hand position as I held the camera higher or lower. Ultra-flexible customization If you're like me, you enjoy taking pictures more than fiddling with camera controls. Nothing saps my picture-taking pleasure faster than endless deep dives into a menu system to get the shots I want. As a result, I think a lot of my pleasure in using the Sony RX1 came down to its ultra-configurable user interface. The ability to assign specific functions to various user-interface buttons is nothing new, but the Sony RX1 gives you more options (a total of 25 can be randomly assigned to buttons) and lets you configure more of the available buttons than is common. While the RX1 offers more configurability than most cameras, that by itself doesn't explain why I took such advantage of it, let alone so quickly. After some pondering, I think it comes down to this: no labels. On most cameras, most of the buttons and controls have labels associated with them. You know; the four-way controller has the four directions labelled something like self-timer, white balance, flash and ISO. Or whatever. While some cameras will let you override these default functions, the labels are still staring you in the face. You have to remember; "Oh yeah, that control says WB, but I've actually reassigned it to metering pattern." At an even more basic level, the label says "this is what this button does", so it may not even occur to you to make it do something else. On the Sony RX1, only the "up" direciton of the four-way controller is labelled (DISP), and that's the function it always has. The other three direction carry no labeling at all. There's a button labeled "Fn" on the camera's rear panel, and one labeled "C" on the top, but those are entirely generic labels that actually suggest you should assign a function to them. The only configurable button that carries a label is the one for AEL (auto exposure lock). The lack of labelled default functions meant that the RX1 immediately confronted me with the question of what I wanted the controls to do. So I went ahead and assigned my own functions to them, where with another camera I might not have bothered. The result was a huge improvement in my shooting experience. I realize I'm spending a lot of time on the RX1's user interface, but that's because it had such a profound impact on my experience with the camera. Here's an example: My first real outing with the camera was in San Francisco, where the tall buildings resulted in a lot of tall/narrow subjects, but where street-level shooting subjects better fit the camera's native 3:2 aspect ratio. No problem, I set the right 4-way button to control aspect ratio, so I could switch from one to the other in a heartbeat. It was a bright, sunny day, so dynamic range was an issue with a lot of subjects. No problem, I assigned the left 4-way button to bring up the DRO/HDR controls. The mix of sunlight and shadows, combined with a clear blue sky also meant that white balance was pretty variable, so I assigned the down-button to white balance. At first, I thought I'd be using the digital zoom feature more, so I initially put that on the "C" button, but as I moved from outdoors to in and back again, I fairly quickly decided that having the ISO setting there made more sense. The result of all this was that I had exactly the functions I most used right at my fingertips, so I spent very little time in the menus, and lots more time actually taking pictures and enjoying myself. I've always been a big fan of buttons rather than menu controls, but the flexibility of the Sony RX1's control system took it to a whole new level for me. A panoply of well-considered features and settings Beyond the RX1's design and handling, it functions superbly as a camera. There are all the controls and options you could hope for, and in my experience, they all worked very well. Taking white balance as an example, it has all the white balance settings you could ask for, including no less than four different settings for fluorescent lighting, three separate custom settings, and the ability to apply manual adjustments to every setting separately, using the by now familiar cyan-red/green-magenta (A-B/G-M) color map. There was one nice tweak that I'd never seen before, though, in that the custom white balance setting process displays the color temperature the camera has chosen, as well as the A-B/G-M adjustment it applied. I really liked the added info, compared to just having the camera just produce the adjustment with no added information. Sony's dynamic-range expansion options worked as well as they always do, with 5 levels of "DRO" (Dynamic Range Optimization), and HDR exposure ranges as high as 6EV. Both the DRO and HDR options have an available Auto setting as well. In both cases, the results were as natural as could be hoped, meaning that the tonal distortion of high levels of HDR was no more than you'd expect from 6EV of dynamic range compression. Also important for hand-held HDR photography, the Sony RX1 micro-aligns the separate images before combining them, so the results are about as sharp as single-shot images would be. I liked the RX1's user interface quite a bit. Some of the settings are displayed as "virtual dials" on the LCD while you're changing them. The 14 creative styles provide a wider range of options than found in most cameras, with settings for things like high-key and low-key shots, as well as the conventional Portrait, Landscape, and Sunset settings. I particularly like that Sony lets you adjust contrast and color saturation for each creative style separately. This is also where you can dial back (or boost) the camera's default image-sharpening setting as desired. I didn't change it on any of my gallery shots with the camera, but I usually dial back a little from cameras' default sharpening settings, so I can do a better job in Photoshop later. Of course, there are also the unique multi-shot scene modes pioneered by Sony, including the incredibly useful Handheld Twilight mode, and the incredibly fun Sweep Panorama mode. The former helps you capture sharp images when shooting hand-held in low light conditions. It does so by snapping a number of shorter exposures, micro-aligning them, and then adding them all together to end up with the same exposure level as a single, longer one. The net result is you can shoot a good two stops slower than you'd normally be able to without using a tripod. Sweep Panorama is probably familiar to everyone by now; you can capture a panoramic shot by just holding down the shutter button and "sweeping" the camera in front of you. The RX1 snaps dozens of shots, and stitches slices from each into a surprisingly seamless panorama. One added note about Sweep Panorama, that accounts for some of why I find it so handy: Most people only think of panoramas for horizontal shots, but they can be incredibly useful for vertical shots as well. I enjoy hiking when I have the time (ie, seldom), and Sweep Panorama is often the only way to capture the full height of a waterfall, working exceptionally well for that purpose. The same could be true of tall buildings in a city, or for that matter any other tall subject that's too close to fit into the frame. Performance, optics and image quality -- oh my! Beyond its groundbreaking size, what really thrills me about the Sony RX1 is its image quality -- and its phenomenal lens. Ultimately, it all comes down to the pictures a camera can deliver, and the RX1 delivers in spades across the full spectrum of lighting conditions and subjects. Image quality isn't just good, it's exceptional. Having a sensor derived from that in the Sony A99, this comes as no surprise: That camera takes great photos as well, and the RX1 more than matches it. Whether it's due to its extraordinary lens, or to a weaker (or no) low-pass filter, images from the Sony RX1 are noticeably sharper than those of its translucent-mirror big brother at low ISOs, and significantly so at higher sensitivities where better noise-reduction processing could be playing a role. What's remarkable to me is just how well the Sony RX1 stacks up against the best the field has to offer. (See the image crops below for specific examples, or help yourself to our Comparometer to compare all our test images, to your heart's content.) And when I say "the best the field has to offer," that's without limitation. Images from the RX1 can be put up against those from literally any 35mm-sensor camera currently on the market and they hold their own, if not better the competition. It's no surprise that the 36-megapixel Nikon D800 out-resolves the RX1 at low ISO, but the D800's smaller pixels exact a price at higher ISOs, where the balance tips in favor of the RX1 again. I really liked the Sony RX1's file quality, especially in its RAW images. There's a lot of latitude for making even significant tonal adjustments; detail comes up out of the shadows without complaint, and with surprisingly little noise. The tonality holds together very well also, with little or no sign of posterizing (quantizing) in the image unless you get really crazy with the tone curves. Where Sony has sometimes struggled with high-ISO noise reduction in the past, the RX1 does an excellent job of preserving subtle detail, and any remaining noise has a nice, fine-grained "filmic" appearance to it. There's also almost no chroma noise, so high-ISO shots look great when enlarged. It really seems like Sony has made some sort of breakthrough in how they handle noise; the RX1 and the A99 are a real step up from their earlier efforts in this area. The RX1's color and white balance were positives, as well. Color's a very personal thing, so this is an area where your mileage may definitely vary, but to my eye the RX1's colors are bright and clean, but always very believable. Like most people, I prefer the color in my photos to be slightly brighter than life, a preference most cameras on the market accommodate to one extent or another. In my opinion, the RX1 gets this just right, but if you feel otherwise, it's easy to make fairly fine-grained adjustments to saturation and contrast in each of the Creative Style settings. When it came to white balance, the Sony RX1 handled difficult and mixed lighting with ease. For me, the test of a white balance system is whether the photos match my perception of the subject when I shot it. This is surprisingly difficult to pull off; the human visual system is incredibly adaptable, and can easily handle both a range and mixtures of color temperature that would give most cameras fits. In my shooting with it, the RX1 did really well in this regard, whether coping with daylight, incandescent, fluorescent or awkward mixtures of any or all of these. While we exercised its various white balance options in the lab, in my personal shooting, I rarely if ever felt a need to use anything but Auto. I've almost never found this to be the case with other cameras. Then there's the lens. (Ah, the lens!) Because our SLRgear lens testing involves cross-calibration between bodies by shooting with a "calibration lens", we can't directly calibrate results for the RX1's lens against those tested on other cameras. Even without close calibration, though, it's clear that the Sony RX1's lens is the sharpest, most uniform full-frame 35mm optic we've ever seen. Period, full stop. Shooting with the camera, it was just amazing to me that I could shoot wide open at f/2, and not feel that the large aperture was in any way compromising the quality of my images. My shots were sharp from corner to corner, even at f/2. Not having to worry about stopping down unless I chose to for photographic reasons was truly liberating. Needing to find the "sweet spot" of the lens became a non-issue. In creating the lens for the RX1, Sony's lens designers took an approach we're seeing more and more lately, taking advantage of the ability to correct images digitally to allow more latitude in some aspects of the lens design. In the case of the RX1's lens, the designers allowed significant geometric distortion and light falloff (shading, aka vignetting), to help them achieve the excellent corner to corner sharpness. Uncorrected chromatic aberration is actually on the low side of normal as well, but after processing through the camera's optional correction algorithm, it becomes truly negligible. The result is a remarkable lens in virtually every aspect: This is by far the highest optical quality we've seen from any full-frame lens of equivalent focal length, including 35mm primes costing $1,500 or more. The one minor fly in the ointment is that the shading correction (which applies to both JPEG and RAW files, but can be turned off) introduces a slight magenta-to-cyan color shift across the frame. See the section below for full details on this, but it's pretty subtle; We saw it in the lab, but I never saw it in shots I took with the camera, even when I was trying to highlight the issue. Technical problems: Exposure bias and color tints In all of my shooting with it and all our lab tests, the Sony RX1's image quality was simply stellar, and its operation flawless. Well, almost. I did find that I was adding about +2/3 EV of exposure compensation to many of my shots. I found I could pretty well just leave the exposure compensation dial set to +2/3 and be happy with the resulting exposure unless it was a contrasty scene with a strong highlight, in which case +1/3 or no compensation worked better to hold onto the highlight detail. This was likely a deliberate choice on Sony's part, and given the price point of the camera, one that's probably justified: Experienced digital shooters know that once you've lost your highlights, they're gone forever, so you generally want to be very conservative in your exposures to preserve them. This means exposing shots a fair bit darker than you would if you were just looking for pretty pictures to use straight from the camera. If you're that type of shooter, you'll b e happy with the RX1's uncompensated exposure choices; if you're not, just dial in +2/3 EV of exposure compensation as your personal default. We did encounter one really perplexing issue in some of our lab shots, namely that they showed a red/magenta to cyan color cast across the images; a very slight reddish/magenta color cast on the left faded into an equally slight cyan cast on the right. The thing is, this color shading didn't appear in all our shots, just some of them in both RAW and JPEG. After a good bit of head-scratching and a couple days of chasing the issue, we finally tracked it down to the RX1's shading compensation. With shading compensation enabled, we got relatively uniformly-exposed frames, but also with the color tints. With shading compensation off. we got darker corners, but no sign of the tint. (Read more about and see the color-shift issue here: http://www.imaging-resource.com/PRODS/sony-rx1/sony-rx1A.HTM) Moir� than we bargained for In the face of ongoing consumer demands for crisper-looking images, manufacturers have been backing off on the strength of the low-pass filters in their cameras, and in some cases, eliminating them entirely. This does produce sharper-looking images, but as they say, there's never a free lunch: The low-pass filters were there for a reason, which is to reduce various forms of aliasing. In digital images, you'll typically notice aliasing in three ways, either as raggedness ("stairsteps") in angled high-contrast edges, in the form of moir� patterns or as color artifacts (really a subset of moir� patterns). The inevitable result of dialing back or eliminating low-pass filters in digital cameras is that artifacts and moir� patterns will rear their ugly heads. Note that it isn't a matter of just using clever image processing algorithms to get rid of them. While some forms may be subject to detection and removal, by definition, aliasing is impossible to completely distinguish from valid image data. We bring this up, of course, because we found evidence of aliasing in the RX1's images, in both still and video captures. The crop to the right shows one of the more noticeable examples of aliasing we found, in a brick wall of a local City Hall, while the video clip shows moir� patterns in a neighbor's house. The latter are among the most severe we've seen with that particular subject. The good news is that moir� patterns are only likely to be found in man-made structures, where there are repeating patterns or textures not found in the natural world. A nature photographer would probably never notice a moir� in their subjects, but someone shooting a lot of buildings and architectural details could run across them quite often. As noted, the RX1 isn't the only camera these days that's prone to moir� issues: They're present in the Nikon D800 (both the normal and "e" version; the low-pass filter in the standard D800 is fairly weak, a big part of why its images are so crisp), the Nikon J1 and V1, to a lesser extent in the Olympus E-P3, of course in the Pentax K-5 II s (the version with no low-pass filter), in the very sharp Panasonic FZ200, to a lesser extent in the Samsung NX1000 and Sony's own NEX-7, and doubtless many others we haven't taken time to tally here. As with everything else, you'll have to decide whether this will affect your own photography or not. If it bothers you, you're going to have to give up some sharpness to get rid of it, since the only cure is an image with less high-frequency detail. If you don't want to give up superior sharpness in all your photos for the sake of the moir� problems in a few, there is a workaround; when faced with a problematic subject, just throw the focus very slightly off in one direction or another. The resulting softer image won't contain the too-high spatial frequencies that were the cause of the problem, so the moir� patterns should disappear. The only trick with this off-focus workaround is to blur things slightly enough so you don't end up with an over-soft image. The video moir� seems more severe. If you intend to record a lot of video of man-made objects, the Sony RX1 might not be for you. Speaking personally, I'm much more interested in photos of people and nature than I am shots of city scenes, so the level of moir� the RX1 seems prone to wouldn't be an issue for me. Others with different shooting preferences obviously might feel differently. The feature that didn't make it (Continuous Autofocus) We didn't initially pay much attention to the Sony RX1's focus tracking, as it wasn't highlighted as a particular feature, nor was it one that would have much impact on our own use of the camera. As we were finalizing the review, though, tech editor Zig noted that Sony's online documentation for the RX1 said that tracking focus "tracks the subject and adjusts the focus automatically even when the subject is moving", and also that "The focus setting for the first shot is used for following shots" in Speed Priority mode. He asked us to confirm that the focus didn't track in Speed Priority mode, but did in normal Continuous Shooting mode. Much to our surprise, we couldn't get the camera to track focus at all in continuous shooting mode, regardless of the tracking AF setting! Say what? We clearly remembered seeing an AF-C (continuous AF) option on the camera somewhere, but couldn't find it on our production sample. Checking photos of the prototype body (including Sony's own initial PR shots), we saw that there was indeed an AF-C setting on the focus mode dial that apparently was deleted from production models. There's also an obvious gap in the Fn button settings display, where the focus mode setting would normally appear. When autofocus is enabled, the camera displays AF-S in still image mode, but AF-C in video mode. This suggests that there was a problem with continuous AF that Sony wasn't able to solve before the design and firmware were frozen for final production. However, AF-C is still the default for video shooting (as noted, an AF-C indicator appears on the LCD screen in movie mode), so perhaps it was just a matter of not being able to maintain still-resolution focus accuracy, and the feature worked fine for video recording. Resolving to find out, we did a series of AF tests in video mode, both with and without subject tracking enabled. The video AF tracking results were extremely disappointing; the camera had great difficulty tracking a subject moving at any speed. While still-mode autofocus is both reasonably fast and dead-on when shooting one image at a time (pressing the shutter for each shot), the focus is fixed on the first shot in a series in continuous-shooting mode, regardless of the tracking setting in the menus. And in video mode, continuous autofocus is almost entirely non-functional. Never mind our usual AF-tracking acid test with a car moving at 30 mph, we couldn't get the RX1 to track a person moving at a leisurely stroll. There's no way around it, this is a significant failing. Speaking for ourselves (the various editors who've been involved in writing this review), it wouldn't keep any of us from buying an RX1, since we don't really care about tracking AF in video that much, and with its wide-angle lens, we wouldn't be using the camera for sports shooting either. It's a simply phenomenal still camera, with an incredible lens and a great user interface, truly a joy to shoot with, and we'd happily buy and use it on that basis. If you're a non-sports still-shooter, we expect you'll feel the same. We think that people interested in shooting sports or video will likely be attracted to other cameras in the first place. Is this something that could be fixed in firmware? Impossible to say, but if it was a straightforward fix, it would have been applied before the camera started shipping. It's our guess (and admittedly nothing more than that) that the problem goes deeper than firmware, down to the mechanics or electronics of the camera/lens system itself. Bottom line: The joy of photography Even though I missed having a zoom lens, I can honestly say I haven't in recent memory had as much fun with a camera as I did with the Sony RX1. I couldn't be happier with the quality of the images it delivered, the lens was a revelation (you mean I really, really don't have to stop down to get a sharp image?), and the customizable controls meant I spent a lot more time taking pictures than digging through menus. I've waxed euphoric about the RX1's image quality above, but it really deserves special mention when summing up my experience with the camera. The resolution is just incredible, which to some extent mitigated my dismay over the lack of a zoom lens. Frankly, you can make a perfectly nice 8 x 10-inch print with just 6 megapixels (3 megapixels, if you're planning to hang it on a wall and not squint at it). This means you can crop away half of the frame and still have enough resolution to make a very nice print to sit on the side table or hang on the wall. Going to 3 megapixels, you can crop away 7/8 of the frame, and 99% of your friends still won't be likely to notice. Cropping, of course, is what the RX1's digital telephoto does, and this is perhaps the first camera I've shot where I considered that a reasonable option. Resolution is only a small part of it, though -- the ability to shoot at crazy-high ISOs with a pocket camera changes the game in important ways. Just as the lens freed me from worrying about staying in its sweet spot, the Sony RX1's super-clean high ISO files meant I could by and large stop worrying about ISO as well. I mean, with a tack-sharp f/2.0 lens and ISO 6400 that'll make decent 11x14 inch prints, who needs a flash? I often carry a pocket camera of some sort when I don't want to lug along a bulky SLR, but it's always a painful experience, knowing how poor the images will be indoors or after dark. With the RX1, that concern completely fell away. The word I keep coming back to is "liberating": The RX1 liberated me from a whole range of concerns I'm accustomed to dealing with, and let me concentrate on taking the pictures I wanted. As noted above, we did find some limitations and foibles that the RX1 was subject to, but they had very little impact on my own shooting, and wouldn't in any way keep me from purchasing an RX1if I were in the market. At least for the sort of photography I'm interested in, the positives vastly outweigh the few negatives. (See the IR lab's image-quality analysis of the Sony RX1 here: http://www.imaging-resource.com/PRODS/sony-rx1/sony-rx1A5.HTM.) -------------------------------------------------------------------------------------------------------------------------------------------- QUICK HITS: Nikon D7100 hands-on preview, Rediscovering photographer Roman Vishniac Hands-on Preview: Nikon D7100 launches with no low-pass filter; Nikon believes moir� no longer an issue By Mike Tomkins Back in late 2010, Nikon debuted the D7000, an enthusiast SLR that has since proven very popular. In some ways an evolution of the earlier D90, there was still enough differentiation to consider the Nikon D7000 to be the start of a new model line. Today that line continues with a brand-new camera -- the Nikon D7100 -- sharing much of the D7000's DNA, but with improvements throughout. Some of these new features are drawn from Nikon's professional cameras, others from consumer models, and a couple of the most interesting are unique to the D7100. Key changes include a new, higher-resolution image sensor which looks to be related to that used in the Nikon D5200, as it shares the same 24.1 megapixel resolution. Importantly, though, it lacks that camera's optical low-pass filter, and so should yield better per-pixel detail -- but it remains to be seen at what expense in terms of moir� and aliasing artifacts. Clearly, Nikon is confident that it won't be an issue, with its press materials noting their defiance of convention and suggesting their "high resolution and advanced technologies" make the OLPF unnecessary. We're skeptical, given the mathematics of undersampled signals, and what we've been seeing in recent camera tests. Read our Nikon D7100 hands-on preview here: http://www.imaging-resource.com/PRODS/nikon-d7100/nikon-d7100A.HTM ------------------------------------------------------------------------------------------------------------------------------------------- Roman Vishniac: Rediscovering his photographic and enigmatic genius By Steve Meltzer The International Center of Photography in New York is presenting an intriguing show of hundreds of photographs by the Russian-American photographer Roman Vishniac from Jan. 18 to May 5, 2013. The title of the exhibition is "Roman Vishniac: Rediscovered," but a better title might have been "The Enigmatic Roman Vishniac." Photographer and curator Cornell Capa -- younger brother of photojournalist Robert Capa -- introduced me to Vishniac in the late 1960s. He had met Vishniac a couple of years earlier and they had become close friends. Both were secular Jews who had fled Europe to settle in New York City. From that first meeting, it was clear to me that both men were extremely sure of themselves. Their friendship was based on both their common European backgrounds, and their strong belief in photography as a tool for social activism -- a somewhat romantic notion today in the age of the smartphone. Capa and Vishniac felt that if you showed people photographs of social problems, they would take action to fix them. For Capa, Vishniac's photography of the Warsaw Ghetto and village life in Eastern Europe before World War II fit this bill perfectly. Read more about Roman Vishniac and see his photos here :http://www.imaging-resource.com/news/2013/02/15/roman-vishniac-rediscovering-his-photographic-and-engimatic-genius -------------------------------------------------------------------------------------------------------------------------------------------- WE'VE GOT MAIL: Questions from readers, answers from IR We thought our readers would be interested in the following exchange, triggered by a site reader's response to our news post about a new HTC camera phone that boldly cuts sensor resolution in half, in exchange for better light sensitivity and noise performance. All well and good, but reader Simen01 accused us of propagating the "resolution kills sensitivity" myth in a comment. My reply may have been akin to killing an ant with a sledgehammer, but I really don't like being accused of propagating myths. Here's the (admittedly somewhat one-sided) exchange: Simen01: Oh no! The "resolution kills sensitivity" myth gains ground. Per pixel noise isnt relevant. Sensor size is! http://www.luminous-landscape.com/essays/dxomark_sensor_for_benchmarking_cameras2.shtml Dave Etchells: The article you point to is certainly extensive, but it doesn't really address the issue of pixel size very well. The author admits that he's combining results from multiple generations of sensors, and if you look at his data relative to sensor size (see the upper left plot of this chart:�http://www.luminous-landscape.com/articleImages/PvdH3/Fig2_183.png you'll see that there are enormous variations of DxOMark score for many of the sensor sizes shown. He plots DxOMark vs megapixel count, and of course, with fixed MP count, larger sensors do better, as he's indicated here and there on the chart. Bottom line, though, he shows scads of graphs and charts, but never the one that would be most interesting, namely score vs actual pixel dimensions. Even doing that wouldn't give a very accurate picture, though, because it wouldn't factor in different sensor technologies and generations of development. He's mixing technologies like backside illumination, probably 3 or 4 generations of pixel layout, a similar number of generations of microlens development, etc. The author also focuses entirely on shot noise as the dominant noise source, but doesn't give any justification for that assumption. In fact, there are three sources of noise in semiconductor sensors, namely shot noise, dark current, and Johnson (thermal) noise. Here's a brief article that describes all three:�http://optical-technologies.info/noise-in-photodetectors/. Then there's electronic noise in the amplifier circuitry, noise from signal cross-talk within the camera, and doubtless other sources I'm not immediately aware of. Dark current isn't negligible when compared to shot noise, especially at low illumination levels (high ISO settings). Dark current noise is essentially the shot noise of the reverse-bias leakage current of the photodiodes in the detector. Ignoring surface leakage (which is yet another factor, albeit a small one in modern detector designs), this leakage current occurs as hole-electron pairs are randomly created in the depletion layer of the photodiode, and the newly-formed carriers are pulled into the photodiode's well on one side and the bulk silicon on the other. The depletion layer surrounds the photodiode on all sides, so leakage there will be proportional to the perimeter of the photodiode, while the detector's light sensitivity will be dependent on its area. Detector area is proportional to the pixel's linear dimension squared, while perimeter is directly proportional to the linear extent. Thus, as you reduce the size of a pixel, the ratio of the noise-generating depletion layer size to the area of the pixel will increase directly proportional to linear dimension. In other words, every time you halve the size of the pixel, dark current noise will roughly double. Because the depletion region surrounds the pixel on all sides, just averaging the values from smaller pixels doesn't get you back to the noise level of a larger pixel, as the author suggests. In the author's "bucket" diagram, there should be noise-generating depletion regions around each bucket, so when it comes to explaining noise, the "volume" of four of the smaller buckets doesn't equal that of one larger one. There's also the matter of "fill factor", the amount of the pixel area that's actually devoted to light collection. As pixels get smaller, the wiring and circuitry necessary to connect them to the readout circuitry at the edges of the array takes up a larger and larger percentage of available space. This peripheral circuitry is essentially a fixed size (for a given sensor technology and design), so the reduction of active area isn't linear: At sufficiently small sizes, it diminishes quite rapidly. The author acknowledges this in a Q & A to the article, but seemingly dismisses it as an issue. It may be that he's restricting his "pixel size is meaningless" argument to large-pixel cameras, but his graphs include some very small-pixel cameras. - And in the case of cell phones, as discussed in the news item above, we're way into the regime where fill factor is a serious issue. The real bottom line is what shows up in the final images, particular when printed at constant size regardless of pixel count or sensor size. Taking that as a standard, we (at IR) can very confidently say that we've seen a net decrease in image quality in recent years, as digicam models from newer generations in many cases can't actually make acceptable prints as large as their forebears. We also very often see cameras with similar sensor size where the one with higher pixel count wins on detail and resolution at low ISOs, but loses at higher ones. To some extent, trying to make comparisons of noise vs pixel size between cameras and manufacturers is a fool's errand, because differences in the underlying sensor technology often result in much larger differences in image quality than those attributable to pixel dimension. The fact remains, though, that we've seen multiple examples of newer cameras with higher-resolution sensors noticeably underperforming their lower-resolution predecessors. Dave Etchells -------------------------------------------------------------------------------------------------------------------------------------------- NEW ON THE SITE At http://www.imaging-resource.com/new-on-ir you can keep track of what's new on our main site. Among the highlights since the last issue: - Photo: Rove around Mars in this awesome 360-degree interactive panorama experience (http://www.imaging-resource.com/news/2013/02/22/rove-around-mars-in-this-awesome-360-degree-interactive-panorama-experience) - Video: GoPro camera captures jaw-dropping footage of a diver hitching ride on a great white shark (http://www.imaging-resource.com/news/2013/02/19/gopro-camera-captures-jaw-dropping-footage-of-female-diver-hitching-a-ride) - Lens Review: Canon EFM 22m f/2 STM (http://www.imaging-resource.com/news/2013/02/03/lens-review-canon-24-70mm-f-4l-is-usm) - News: The moment meteor explodes over the Russian city (http://www.imaging-resource.com/news/2013/02/17/caught-on-video-the-moment-meteor-explodes-over-russian-city) - Video: Official trailer for intriguing new documentary about the lost photos of street photographer Vivian Maier (http://www.imaging-resource.com/news/2013/02/15/watch-this-trailer-for-an-intriguing-new-documentary-about-the-lost-photos) - Photo: Paul Hansen�s dramatic news image named World Press Photo of the Year (With some interesting reader comments about the lighting: Was it artificially lit?) (http://www.imaging-resource.com/news/2013/02/15/Paul-Hansens-dramatic-news-image-named-World-Press-Photo-of-the-Year) - News: Olympus denies rumors it will scale back or exit DSLR business (http://www.imaging-resource.com/news/2013/02/13/olympus-denies-rumors-it-will-scale-back-or-exit-dslr-business) -------------------------------------------------------------------------------------------------------------------------------------------- NEXT ISSUE Our next issue will be mailed to you in two weeks, on Friday, March 8. We'll have several new camera reviews lined up for your reading pleasure, some more Latest from the Lab notes and observations, as well as the latest news and views. -> And we know, we know: We promised to fix the long line lengths in this issue, but it's been an over-packed couple of weeks again, and we frankly lost track of that particular to-do in the shuffle. We've re-inserted it in our to-do list, will hopefully remember to get to it, this time around. The Sony RX1 review that we excerpted Dave's Shooter's Report from above was part of the busyness, and another part was all the prep work for the first-ever Imaging Resource Camera of the Year awards(!) You're hearing about this here first; the rest of the world will know sometime next Monday afternoon. We won't divulge the winners even to you, but will say that the Sony RX1 figures prominently in the lineup :-) SIGNOFF That's it for now, but between issues visit our site for the latest news, reviews, or to have your questions answered in our free discussion forum. Here are the links to our most popular pages: Newsletter Archive: http://www.imaging-resource.com/cgi-bin/dada-nltr/mail.cgi/archive/irnews Happy snapping! You are currently subscribed to the Imaging Resource Digital Photography Newsletter as: BULK_EMAIL To unsubscribe click: http://www.imaging-resource.com/cgi-bin/dada-nltr/mail.cgi/u/irnews/BULK_EMAIL
The Imaging Resource Digital Photography Newsletter is published by Imaging Resource (http://www.imaging-resource.com) as an advertising-supported email newsletter to opt-in subscribers and simultaneously in HTML on the Web every two weeks. We bring you industry events like the Consumer Electronics Show, Photokina, and CP+ -- which we actually attend, providing live coverage on our Web site. And we report on digital cameras, storage mediums, scanners, printers, image editing software and services for digital imaging (like online photofinishing, framing and album sharing) as they are released. In addition we publish on-going tutorials designed to help you get the most out of their investment in digital imaging no matter what level of expertise you enjoy. Each newsletter will bring you excerpts from our latest tests and hands-on reviews, interesting photo-related stories, and the top news items on our site since the last issue. Subscribe to IR-Newsletter: Thanks for using our Subscriber Services!
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