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Make Your Own Digital Camera ISO Test Target 139

dpnow writes I run a digital photography site and came across what I thought might be an interesting story. It's about a Cornell university researcher that has reverse-engineered the design of the ISO 12233 resolution test target, used by all the best digital camera testers. These usually cost over $100 but a free pdf download of the target is available. Print it out on a good quality printer and you have your own ISO-spec test target so you can find out how good (or bad) your camera really is! "
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Make Your Own Digital Camera ISO Test Target

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  • Great... (Score:5, Funny)

    by inkdesign ( 7389 ) on Monday October 18, 2004 @08:37AM (#10555264)
    I love ideas that make me feel like I got less than my money's worth AFTER THE FACT!
  • Or... (Score:4, Informative)

    by tomcio.s ( 455520 ) on Monday October 18, 2004 @08:39AM (#10555271) Homepage Journal
    frequent and get professional reviews of cameras.

    Dpreview carries digital camera reviews dating back to 1996. They are usually very detailed.

    • Re:Or... (Score:4, Informative)

      by Zog The Undeniable ( 632031 ) on Monday October 18, 2004 @09:13AM (#10555480)
      At the risk of creating a "me too" thread, Steve's Digicams [] is also pretty good. If a camera is junk, he says so, but the full size sample pictures are the really useful feature.
      • Re:Or... (Score:4, Insightful)

        by jovlinger ( 55075 ) on Monday October 18, 2004 @11:47AM (#10556617) Homepage
        Steve never met a camera he didn't like.

        The intro's are just rehashes of the press releases, and all the test shots are done in bright light, out doors.

        For a camera to suck under those conditions, it'd have to ship from the factory with grease on the lens.
      • by ckedge ( 192996 ) on Monday October 18, 2004 @11:57AM (#10556701) Journal
        Why does his "the best cameras" aka "pick of the litter" page have 10 (ten) cameras listed for each of the 12 categories? He says the "cameras are not listed in order of preference": []

        I can see 2-4 choices per, but 10?

        Digital camera reviews are no where near as technical and detailed as they need to be to be useful, compare this: amples.html []

        with this: chmentid=118010&stc=1 [] 1193&page=7&pp=15 [] chmentid=180976&stc=1 [] chmentid=221673&stc=1 []

        Note the "pre-printed form letter" the one guy gets back from his warranty servicing with the check mark beside the following paragraph:

        "Your camera is operating according to factory specification in all modes. The phenomenon you have experienced (an orange halo visible in the bckground after taking some pictures) is not a defect in operation of your camera. It is a function of the geometry of the lens optics. Under certain lighting conditions this effect may be noticeable. Darker backgrounds will minimize or eliminate this effect."

        You can no longer find the S3 or anything like it on the market, Casio has probably quietly removed it due to huge numbers of returns and warranty servicing costs. You can only find a few on eBay, and ALL are "open return" or "used return, not tested". NONE sold by happy users.

        AFAIAC, digital camera reviews are nearly worthless, no matter who is doing the review.
        • AFAIAC, digital camera reviews are nearly worthless, no matter who is doing the review

          Wow, that's a strong statement from someone who's never googled for "digital camera review". The first hit is They have fewer reviews for different camaras (ie, they don't test every single camera out there), but their tests are lot more thorough, with measurements on lens resolution, distortion, white balance, fringing, etc. Sure, their focus is more higher end cameras, but they do cover point-and-shoot
          • by ckedge ( 192996 ) on Monday October 18, 2004 @08:43PM (#10560857) Journal
            I've seen of course. I don't remember anything standing out. But, on your word, I'll go back and check what it's like these days.

            [goes away, comes back 15 minutes latter]

            Hmmm, ok, I like their "buying guide" that allows you to choose features you want then list all camera's side by side. However - the table is missing a few things (like start-up-time, inter-picture delay, shutter-lag, etc), and the camera I had pointed out is given 4 stars out of 5 despite the massively poor picture quality of this camera, in fact ALL the 10 cameras have 4 stars out of 5 - the star rating is user driven. ONLY 2 of the 10 cameras have in-depth reviews by the dpreview site staff themselves.

            They do have a page where they rank cameras by their own review rankings, but it's all mixed together, it'd be a huge pain in the ass to figure out which are the ones I'm interested in and which are on the market, price differences, etc etc. They need to review a larger fraction of the cameras on the market, and add this data to the comparison table.

            One thing that is impressive is the last two rows in the comparison table, where they show a resolution chart snapshot and color chart snapshot. The color chart snapshot clearly shows the horrific quality of the camera I was talking about. Unfortunately like the reviews, they are only there for some of the listed cameras.

            I give 6 stars out of 10. Steve's digicams gets 4 stars out of 10.

            What I want to see is 8-10 stars out of 10 for a rewview site. Isn't this the information age? Where the FUCK ins the information? It's supposed to SAVE me time, not consume my time, and it's supposed to DECREASE the odds of crappy products thriving.
  • Cost over $100 ??? (Score:4, Informative)

    by sbryant ( 93075 ) on Monday October 18, 2004 @08:39AM (#10555276)

    Somebody can't read! It said over 100 pounds ($180).

    Insert comment here about people of a certain nationality making too many assumptions about units of various things...

    -- Steve

    • Pwned. (Score:2, Informative)

      by op00to ( 219949 )
      Pwned. []

      Photography - Electronic still-picture cameras - Resolution measurements

      ISO 12233:2000 paper version (en) CHF 116,00

      116.00 CHF Switzerland Francs = 94.2233 USD United States Dollars

    • by erick99 ( 743982 )
      From the article:

      The ISO standard for measuring resolution of "electronic still imaging"" cameras is 12233, available only from the International Standards Organization for only 116 Swiss Francs (about $US93 as of this writing)

    • So what's the problem? 100 pounds is certainly [] over $100.

      Way to go Steve-o

      photos []
    • Is this another case of us brits paying in UKP what the yanks pay in USD?
    • by Lord_Slepnir ( 585350 ) on Monday October 18, 2004 @09:06AM (#10555444) Journal
      You're right. I apologize to you on behalf of everyone here in america. For your convience, I have converted the price to a more european-friendly unit.

      It cost over 45.35 kilograms

      • WooHoo I knew that if I held on to those copper and iron pieces they would eventually gain in value!
      • ou're right. I apologize to you on behalf of everyone here in america. For your convience, I have converted the price to a more european-friendly unit.

        It cost over 45.35 kilograms

        How many square football fields per forthnight is that???
      • I graciously accept your apology on behalf of Europe (though it's "kilogrammes"), and send you a vial of culture as a peace offering.

        I'm tossing it in your direction with a force of 27 slugs. Oh no, was it imperial slugs or metric slugs?

        Seriously, like the slug, imperial units are slimy. This is one instance where europeans (especially engineers) can be justifiably smug.
      • Incidentally, here in the UK, we mostly use lb still in daily life, even though "officially" we're supposed to use metric measures. To make it even more confusing, we use miles exclusively (except in scientific areas, but even NASA use Km...) Cheers & God bless Sam "SammyTheSnake" Penny
      • It cost over 45.35 kilograms
        Damn you and your millimetrics!
    • so... why would someone in the United States (as Corell University is) quote prices in GB Pounds?
      Answer? They wouldn't... if you had read the real article [] (you know... the one that links to) you would have seen the following:

      The proper way to perform these tests is to order both the ISO standard and a properly-made test chart. The latter are available, for example, from Sine Patterns LLC and Precision Optical Imaging, both in Rochester, New York. See the the I3A site for worldwide sources. Expec

    • by jemfinch ( 94833 ) on Monday October 18, 2004 @10:36AM (#10556089) Homepage
      No, it said (and I quote from html):

      The ISO standard for measuring resolution of "electronic still imaging"" cameras is 12233, available only from the International Standards Organization for only 116 Swiss Francs (about $US93 as of this writing)

      Insert comment here about people of certain other nationalities applying rude, unfounded stereotypes to people of my nationality.

    • Technically, 100 pounds is more than $100.
    • Perhaps you didn't notice but 180 > 100 hence the statement is entirely correct, if slightly misleading.
    • Somebody can't read! It said over 100 pounds ($180).

      Somebody can't math so good. 180 USD > 100 USD. So yes, more than $100.


  • misdirection (Score:5, Informative)

    by Anonymous Coward on Monday October 18, 2004 @08:42AM (#10555290)
    the article links to a story which links to the actual content you want. To get to the real content, thus bypassing the advertisements that they wanted you to view in the first place, go here: html []
  • Site (Score:5, Informative)

    by WhatsAProGingrass ( 726851 ) on Monday October 18, 2004 @08:42AM (#10555294) Homepage
    • Re:Site (Score:4, Informative)

      by Pieroxy ( 222434 ) on Monday October 18, 2004 @08:52AM (#10555362) Homepage
      Well, not printable size, and thus, not free. The link you point to is the very reason someone got through the trouble of redoing it by himself.

      Thanks though, this is informative.
      • Re:Site (Score:2, Informative)

        Yes true, its not free, but just thought it had some more info people might be able to use.

        Looks like you'd need a pretty expensive printer to print these out. Some of the images are 80 cm wide.
        • You'd need an increadably expensive printer to print them out, there resolution test charts, even this free version won't be sutable for professional work even printed at 1200x1200... though, it's a good way to test youre printers resolution :)

          And hell, find a good lazer like above and youve definately got something good enough to test out webcams, phone cams, and cheaper digital cameras.
  • by Mstrgeek ( 820200 ) on Monday October 18, 2004 @08:44AM (#10555306)
    This is a great site dealing with Digital Camera ISO Test Targets cs/lens-tests.html

    hope you are able to find to find the site a help

  • by sdo1 ( 213835 ) on Monday October 18, 2004 @08:45AM (#10555307) Journal
    so you can find out how good (or bad) your camera really is!

    Or so you can find out how good (or bad) your "good quality" printer is.


    • by ajs ( 35943 ) <ajs.ajs@com> on Monday October 18, 2004 @10:31AM (#10556061) Homepage Journal
      Yep, I have a Canon E300 (AKA Digital Rebel, AKA Kiss), which, at 6MP and with my good macro lens (since I don't need any depth of field for taking a picture of a sheet of paper) can literally tell you how good your paper selection is, and that's the "prosumer" grade camera. Grab yourself one of the "professional" digital cameras (like the E20), and you're going to be able to determine the components of the ink, based on the way the paper separates it through capillary action.

      These test sheets are fine for low-end cameras, but once you start dealing with professional lenses and high resolution CCDs you really need something printed by a professional printer, not some cheesy home unit (even if the home unit has the same resolution as the camera, it may not be capable of reproducing the image on paper with enough fidelity to test the camera.
  • by poszi ( 698272 ) on Monday October 18, 2004 @08:45AM (#10555309)
    With description of the optics and details of the resultion measurements is here []. He created also his own chart which includes shades of grey for better measurements of MTF50.
  • Or.... (Score:5, Interesting)

    by Halo- ( 175936 ) on Monday October 18, 2004 @08:47AM (#10555331)
    Or find out how crappy your printer is. Seriously, what do you think is more precise, the electronics in your cheap digital camera or the moving parts and alignment of your cheap printer? Curve dithering is one of the harder aspects of printing, this target seems to rely heavily on them.

    This is a fun toy to play with, but I'd trust professional reviews.

    • My laser printer seams to print out very nicely, I mean if my camera is only 1700 pixels and the printer is 600dpi , thats like 5x the res of the camera, so even at 4feet 200dpi will look the same.
    • You could put the PDF-file on a CD and take it to a professional printing place. They'll probably do it for about $10-15.
    • Re:Or.... (Score:3, Insightful)

      by gl4ss ( 559668 )
      actually, the chances are that the crappy printer prints more accurately than what the camera can capture.

      • Just printed the sheet. Printer can't handle 12lpm. Can't handle any slant targets. Can see the vertical swipe target but using a microdensitometer note that the line spacing is of poor quality.

        I guess I should junk my 1000$ Lexmark and find something better.
    • Re:Or.... (Score:2, Insightful)

      by timster ( 32400 )
      Since the target consists only of solid black and solid white, I don't understand what role dithering has in this. Although there are curves, I don't think it's important that they be anti-aliased.

      Mostly I think this is a question of the resolution of the printer. At 800x zoom on my 100 dpi monitor I can see all the small features clearly, so I expect a 1200dpi laser would render this image just fine. At 600dpi you might miss some of the fine details.
    • Unless the professional reviews are sponsored by the camera manufacturer or an affiliate. Or they gave the reviewer a free camera in exchange for a favourable review. Or the manufacturer poisoned some web forums with fake comments saying "my (whatever brand) camera is awesome! You all should buy one!"
  • by Anonymous Coward on Monday October 18, 2004 @08:48AM (#10555335)
  • new excuse! (Score:5, Funny)

    by Anonymous Coward on Monday October 18, 2004 @08:52AM (#10555364)
    I have no intention of doing what this article talks about, yet it is still very useful to me in another way : instead of telling people I'm rearranging my sock drawer and that's why I can't go out galavanting on Saturday night, I'll tell them I'm testing my digital camera's resolution with a reverse engineered ISO 12233 resolution test target.

    Someone should sell t-shirts with this thing on them.
  • For Sale (Score:4, Funny)

    by PoopJuggler ( 688445 ) on Monday October 18, 2004 @09:01AM (#10555414)
    For Sale: ISO Resolution Test Target

    Paypal only, please.
  • Copyright... (Score:5, Interesting)

    by kahei ( 466208 ) on Monday October 18, 2004 @09:09AM (#10555466) Homepage

    Now, there's interesting:

    Westin explains that the ISO specifications can be used without restriction for projects like his, though the copying of a commercially reproduced target is, of course, illegal.

    (see, I _did_ rtfa!) So, it's illegal to reproduce the image, but creating a new image from an exact description of the image is legal. Yet that _is_ what 'reproducing the image' is!

    The reason for this situation is that the image in question is very unusual, in that it has a freely-usable exact description in existance. But what if an exact (text) description of Mickey Mouse were made? You certainly wouldn't be allowed to create new images from it, and yet it's hard to see how Disney would own the rights to that description... hmm...

    • Re:Copyright... (Score:4, Insightful)

      by gblues ( 90260 ) on Monday October 18, 2004 @09:38AM (#10555673)
      Well, in your example, the description of Mickey Mouse IS owned by Disney. The description that the ISO specifications provide is free for anyone. The trick is actually implementing it. The commercially reproduced version costs 100 pounds, this version costs less (but may not be usable if you have a crappy printer).

      It's sorta like the Bible. The actual scriptures are public domain, but the various translations--NKJV, NIV, etc--are copyrighted. I can go get the original Greek/Hebrew/Aramaic texts and translate them myself and get a result that is very close to an existing translation, and it is not illegal.

      • Mostly true with the bible. However, NKJV is NOT copyrighted. You can copy it as you please. However, if you're distributing the New International Version (NIV) on the internet expect a cease and decist order from Zondervan.

        Back when I was helping write the mIRC script 'c-script' we used to ship it with NIV. However, we received a cease-and-desist from Zondervan and were forced to remove it. Oh the irony of using copyright to stop the spread of the bible...

        I understand they need to pay the translators and
        • Yea, it's even more ironic when they make you pay for singing Bible verses. Our Band [] has a song that uses Psalm 18:46, 'The Lord Liveth and blessed be my Rock and let the God of my Salvation be exhalted.' There are around 4 other songs that people have written using that verse, and we only sing it for exactly 38 seconds, thus not allowing us to get around the '30 second' rule. Since this is our first CD, we weren't sure how the copyright issues would work out, so we went ahead and gave credit to the most re
        • Re:Copyright... (Score:3, Informative)

          by swillden ( 191260 ) *

          NKJV is NOT copyrighted. You can copy it as you please.

          The NKJV is copyrighted, though the copyright holder's (Thomas Nelson) policies [] on the use of its material are fairly liberal. You can't print full copies, but you can quote lots of it.

          Perhaps you're thinking of the KJV, which is actually copyrighted as well, but the copyright has no legal force outside of the UK and isn't, I don't believe, enforced there, either. See the Wikepedia article [] for more information.

    • Re:Copyright... (Score:3, Insightful)

      by Suidae ( 162977 )
      How exact of a discription is allowed? I can describe a high resolution bitmap very accurately by writing out the color values of each pixel, but I doubt that would be permissable.
  • My eyes (Score:1, Funny)

    by vurg ( 639307 )
    I think there's something wrong with my eyes. All the lines look crooked to me.
    • Re:My eyes (Score:2, Funny)

      by nortcele ( 186941 )
      I think there's something wrong with my eyes. All the lines look crooked to me.
      You are going blind! Your mother warned you about this...
  • by Zocalo ( 252965 ) on Monday October 18, 2004 @09:55AM (#10555809) Homepage
    1. Throw away any test charts into the corner of the room
    2. Toss any rulers on top of the test charts
    3. Newspapers? - on top of the rulers
    4. Avoid any brick walls
    5. Pick up camera (and attach lens if applicable)
    6. Go outside (yes, it really does exist!)
    7. Shoot numerous pictures of various subjects, at varying apertures, focal lengths and durations. Using a flash for some of the shots would be a good idea too.
    8. Make some nice large prints of your efforts
    9. Do the prints look OK to you? If they do, congratulations - consider the test passed, and you might even have a few prints you can actually use for something as well. If not *now* it's time to retrieve the test charts, rulers etc.
    Seriously, the only people that really need these charts are people that are designing or calibrating imaging systems. A charming term that I think was coined over on DPReview to describe everyone else is "measurebator". Believe me, if you've got a lens bad enough to make a difference visible in a print, then you'll know it without any test charts. I had a lens that backfocussed, a Nikon zoom lens I got for my film camera some years ago. I picked up the problem without test charts just fine (I often focus on an eye in portraits), and so out came the rulers, or in my case a newspaper. The largest focussing error in the series of test shots that I took was less than 2mm at a range of 3m.

    Needless to say, I've never touched a test chart, or any facsimilie thereof, since then. The *only* chart that I do have is a Gretag Macbeth colour chart (it's a grid of 24 coloured squares) to get colour balance correct. I also have a couple of Kodak Grey cards for setting white balance if you want to nit pick and call one of those a "chart".

    • I agree that most average users don't need to absolutely quantify the quality of their camera. But there are a select bunch of folks that want to scientifically analyze the quality of their imaging device.

      Subjective measurement will get you so far, but the eye is easily tricked by things like sharpening algorithms.

      For those who do wish to quantify the many dimensions of image quality, my company produces a piece of software called Imatest that analyzes these charts. []

      It also analyzes y

  • by dmadole ( 528015 ) on Monday October 18, 2004 @10:06AM (#10555890)

    Can't anyone write anything tech without feeling the need to throw in a highly-charged buzzword?

    If you read the chart's creator's web page, he didn't reverse-engineer anything. He created the chart from the published international specification. That's pretty much the opposite of reverse-engineering: engineering. That is, taking a set of specifications and producing a design that meets them.

    But I guess that's not as interesting-sounding.

    • Can't we all take turns viewing the site ... or CACHE it first so that the ./ affect doesn't take hold?

      I can't remember the last [current] article that I've actually been able to read. Few and far it seems.

      Of course with ID# 605,395 it will feel like waiting in line at Jewel.
  • by Infinityis ( 807294 ) on Monday October 18, 2004 @10:12AM (#10555928) Homepage
    I don't quite see how taking a picture of "error 500: Internal Server Error" is going to tell me anything one way or the other about my camera. However, it might explain a thing or two about their server...
  • this helps me a lot (Score:5, Interesting)

    by Anonymous Coward on Monday October 18, 2004 @10:20AM (#10555980)
    I'm in a robotics lab working with a CMUcam. This should help us a lot. Those people whining that "real photographers dont use test charts" seem to neglect that some of us are trying to calibrate cameras for sensors and not just pretty pictures.

    thanks poster
    • We bought our own charts. Oddly enough, We're located in Rochester, NY too. At least those of us not outsourced to china (which was me, too).

      Seriously tho, this target is worthless unless you print it on a LARGE piece of paper with an ultra high quality laserjet printer. Ideally you'd want a real laser, not the cheap LED ones, and furthermore you'd need at least 1200 DPI.

      Inkjet? Forget it. Dot placement is poor quality- your lines will get fuzzy. So is that aliasing or is that bad printer alignment.
  • by lildogie ( 54998 ) on Monday October 18, 2004 @10:24AM (#10556004)
    I loved my inferior camera, and my family snapshots, until I found that they had barely-visible distortions.

    Now I have to find an accurate camera and retake all those photos.
    • Just sell your camera to some 15 year old girl so she can take pictures of herself on the intarweb that hide her imperfections. The more inaccurate the lens the better, as its not like she wont just convert it to black and white and kill the contrast in photoshop anyways.
  • for excess traffic. /. just hit him so hard I can't get anything but "500" errors. Somebody should a warned him.
  • Testing a digital camera is not that complicated:

    1. Take a picture of a red object against white background.
    2. Take a picture of a green object against white background.
    3. Find a person with zits/razor cuts on his/her face and take a picture of that person.

    Compare these pics to what you see in real life. Chances are that your reds will be off and the person will have a skin with more orange in it. If so, throw your camera away, unless you do not care about these things. If your camera is close to th

  • Here's a quick-and-dirty lens test you can do, without all the fancy-schmancy charts:
    Tape a newspaper to the wall. Shoot it square-on. Check for flatness of field, distortions, and vignetting at the edges. Shoot it at an angle, at different aperatures, to test for depth of field. Easy!

  • by Dr. Mu ( 603661 ) on Monday October 18, 2004 @12:40PM (#10557034)
    I printed this out on my HP4MV laser printer at 11 x 17 inches. Its 600 dpi are hopelessly inadequate for this test pattern. The best way to print this would be to take it to a print shop that has a good direct-to-film printer (2540dpi or better) and ask them to make a PMT (positive mat transfer) from the file at the highest resolution possible. You'll get a near-perfect print. But you'll pay about $25, and it may not be archival: some PMTs fade over time.
  • It seems like it ought to be possible to print an enlarged version of the test target spread across a number of pages making the resolution of an average consumer printer adequate.
    My question is, how big would the output have to be, to cleanly show everything on the target, with something like an Epson C82?
  • Why is "Error 404: File not found" such a good test image? I don't get it.
  • Um, this is assuming that your PDF-to-paper path is correctly calibrated and measured.

    Which it probably isn't.

    This is what that money is paying for - a printout of the target that's guaranteed to be within a certain range of variability from the Right Colors. And to have the Right Aspect Ratio. And the Known Reflective Characteristics.

    What you print out on your Epson or HP or whatever, probably using typing paper instead of photo paper, probably with color management off, is not going to work for prec

Always leave room to add an explanation if it doesn't work out.