Image QualityColor: The Automatic White Balance (AWB) system showed an ambivalent performance in our tests: the portrait shot showed an intense yellowish and greenish touch. The fluorescent light (used for all our portrait test shots with all cameras) seemed to confuse the AWB system; it showed a good performance in the shot of the test chart using the same source. The GretagMacbeth chart was reproduced with a slight shift toward darker gray nuances in the blue area while only the brightest gray pattern showed the shift into the yellow and green direction. Just like in images taken with nearly all Nikon cameras, the blue colors showed an extremely high saturation and very high magenta rate. The skin tone patterns on the test chart are reproduced correctly and red nuances gained only a slightly high yellow rate.
Sharpness: The camera showed excellent performance in the resolution tests. The ISO 12,233 chart was reproduced with 3738 of 4000 lines in picture height and only an average overshot effect (based on sharpness filtering). Nevertheless, the standard test box shot shows slightly softer characteristics. The softer touch can be avoided by using higher sharpness settings in the Picture Style mode, which offers a slightly lower setting than the Standard, but also helps to avoid problems like moirés or anti-aliasing effects on hard contrast lines.
iso 12233 resolution chart 21
Pro+ High-resolution images with high dynamic range+ Compact body; easy handling+ Swivel LCD for comfortable photo and video shooting+ Full HD video with manual settings
Scene Dynamic RangeScene NoiseEase of CompositingChroma Key and Skin TonesISO 12233 Chart Aliasing and MTFOECF Dynamic RangeMacbeth Colorchecker Chart Color ReproductionKodak Grey Card Noise AnaylsisSkin Tone Reproduction
To determine color reproduction, the MacBeth Color Checker chart was imaged. The D-21 provides a more true color performance than the FS-700, though render the yellows more desaturated than the reds and greens. The FS-700 displays a more yellow bias over all, and displays noticeable saturation in the true yellow patches.
The star chart in the center of the test target makes it very easy to focus in live view, but first examine the pattern of the chart just out of focus at maximum magnification. On a well aligned lens the star should blur into a fuzzy oval like three of the images below do. A badly decentered lens will blur with a flare going in one direction or another, like the image on the lower left below.
Once any corner is in sharpest focus, move the cursor around to check the other three corners and see if they are all equally sharp again. Field curvature, which is a normal part of lens design, means the corners will have a different focus point than the center. But since our alignment is square and centered to the chart, the 4 corners should all focus at the same point. As long as they do, this part of the test is normal.
A mildly decentered lens may only have one bad corner rather than two like the example above. In that case center resolution is always still excellent, although on an optical bench or in an Imatest lab you might notice the sharpest point of the lens has moved slightly off center, away from the bad corner.
We also run QA checks using Imatest or the optical bench on lenses that have passed this optical testing. When we recheck these lenses, we do find that about 0.5% of are actually decentered. However, if we repeat this optical chart test on those same lenses, they almost always fail the repeat test. In other words human error, not the test itself, let the bad lenses pass.
The image quality of lenses varies from model to model; and therefore, the optical results of the various with-extender combinations also vary.A great lens will typically produce the best image quality when used with the 2x andthe best way to see how specific extender+lens combinations perform is by using the ISO 12233 Resolution Chart Tool.All current extender-compatible lenses have ISO 12233 chart results from the with-extender combinations available (select the longest with-extender focal length value).Compare the native maximum focal length to the extended focal length to see the optical change from the selected combination.
The 2x III adds a small amount of barrel distortion to the lens it is being used with.Since many telephoto zoom lenses have pincushion distortion at their longest focal lengths, the added barrel distortion cancounter the pincushion distortion to a small extent.Note that barrel distortion causes the center portion of the image (top image in the ISO 12233 tool) to be slightly enlarged,which can make it appear to resolve more detail.
The Canon 180 L Macro is a lens that performs very well with extenders.Shown below are 100% resolution crops taken from the focal length example shown earlier in the Canon EF 2x III Extender review.These results show what a very sharp lens, stopped down to f/11 and used with good lighting can produce with extenders.
Each row below the image represents either the bare lens or the lens with the specified extender mounted behind it.In each row, the left-most mouseover label is the native resolution of the combination andthe values to the right show Photoshop CS5 up-rezzed (resized larger) images created from the native image.
As a rule, but subject to change, the Canon lenses compatible with the Canon EF 2x III Extender include fixed focal length L lenses with focal lengths of 135mm and longer,zoom L lenses with at least 70mm of focal length on their wide end (the Canon EF 70-300mm f/4-5.6L IS USM Lens excluded).Canon TS-E Tilt-Shift lenses are not included on Canon's official compatibility chart and do not have the 3 additional gold lens contacts for communicating extender information to the camera,but as their image quality results shown on their reviews show, they can function with extenders.The following list of discontinued lenses fitting these parameters are compatible, but may require camera microfocus calibration for accurate focusing (note that not all DSLR cameras support microfocus calibration):
Anomalous dispersion glass elements are used in the Series III extenders to reduce chromatic aberration and increase resolution and contrast.The Extender 2x II did not have an issue with CA and neither does the III.
While I'm still working on moving towards a better test for cameras, for now we have our standard photo comparisons that should give a good idea of what to expect from a smartphone camera in comparison to other cameras. Our first test is the standard ISO chart, which allows for a good test of maximum resolution.
For this first test, it seems that Samsung hasn't really changed much when it comes to maximum resolution, and in general the Note 4 produces similar output to the Galaxy S5. To verify this and a test of dynamic range, we'll look at a landscape shot next.
Does anyone know where I can download to print(or purchase) a relatively simple chart to test the image quality of binoculars. I have a pair of Celestron Ultima 7x42 made in Japan that I bought many years ago. I'd like to mount them on a tripod, tape the chart to a wall, and find the best focus for each side. I had cataract surgery in one eye and need to make an adjustment with and without my glasses. Any help will be appreciated.
Many years ago I bought a set of binoculars, to test at the shop I was able to take them outside and I found at the end of the road a large brick wall. That was about the best "test chart" I ever found.
Those of us old enough to remember Stephen Ingraham's Better View Desired binocular site may recall his "NEED" test where a crisp dollar bill was used as a resolution target. I've used it myself when comparing several binos under the same conditions. Perhaps not perfect, but still a pretty good indicator of relative resolution in binos.
Thanks to everyone for their responses. I forgot to click on the Follow This Topic tab, so I'm a little late with showing my appreciation. I made a simple chart that is taped to my bedroom wall. Luckily the 7x42 binoculars I have will focus close enough for me to test them from my living room.
Rachal: I've downloaded test charts from the Internet over a decade ago and printed them on photo paper. I used them for testing camera lenses. They are very large Hi Res files so I can't attach them and I don't have the links (perhaps USAF optical test chart?). I switched to using old license plates because I can leave them outside nailed to a post or a tree and use them with minimal set up time. Cracks in the paint by the attachment holes in the license plates have been very useful to compare the resolution of different lenses. I now use the license pates to test binoculars also. Not quantitative, but useful and effective for comparing binocs. Good luck, DrJ1 2ff7e9595c
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