Digital Camera photo comparisons real?

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When comparing several digital camera models I am considering for purchase I notice the comparison pictures of the brick house are all IDENTICAL as to shadow positioning (relative to specific bricks).

I thought the comparison pictures would each be a sample of a picture taken by the actual camera selected, but now I suspect it is the same photo just massaged to look like it would come from the specified camera (i.e. at that camera's resolution etc.)

Otherwise every camera I selected had its shutter released at the exact same second on the same day, regardless of whether I selected a very old model or one of the most recent releases.

What am I not understanding about this site?

-- Dave Teece (dteece@home.com), January 03, 2000

Answers

Hi all,

Sorry for being so laggardly about checking in on our own site's Forum - We're gradually digging out from the review backlog, which process was complicated by our messier-than-anticipated server switchover this last week or so...

Cris has it right, as explained in our article on testing digicams, linked from the "Test Descriptions" link in the Comparometer nav bar, as well as on our "Tips & FAQs" page - you can see this article at: http://www.imaging-resource.com/TIPS/TESTS/TESTS.HTM

Given the confusion that Dave had, we should probably link to this article from every camera review, so people's questions can be answered more directly.

As described in the article on the test suite, we've tried to balance several factors in designing our camera tests. On the one hand, we want to be able to test cameras under exactly identical conditions, but on the other hand want to try to show their behavior under real conditions. The two goals are somewhat at odds with each other though, since any "real" subject is going to change over time, or even from one shot to the next. On the other hand, artificial subjects aren't really representative of what you're likely to encounter in real use.

Our solution to the dilemma has been to use a combination of three types of subjects: "Real" ones, shot under hopefully representative conditions, but subject to some uncontrollable variation (the indoor and outdoor shots of the model, the outdoor house shot referred to as the "far-field test"); Posters, which we can guarantee will be exactly identical from shot to shot and camera to camera, but which aren't completely representative of real-life shooting conditions in that they aren't three-dimensional, and won't show the tonal range of a contrasty "real" subject (the House and Musicians posters); and finally, Analytical Targets, which probably won't resemble anything a real user will photograph, but which are both consistent from shot to shot and also exercise more of the specification range of the cameras. Read the article above for all the gory details and philosophizing that led us to the suite we have.

This being the third or fourth time I've had this question, it clearly qualifies as a "FAQ". - We'll begin linking to the explanatory article on our test methods from every review in the future.

Thanks for the question: My "internet rule of thumb" says that if you took the time to write about it, there's at least a thousand other folks out there who've wondered but not written!

-- Dave Etchells (web@imaging-resource.com), January 16, 2000.


Hi again -

Hopefully obvious from my previous comment, but wanted to say so explicitly: Unlike some "test" sites, we *NEVER* modify the test images without saying so, and then only to demonstrate the images' behavior under Photoshop or other manipulation. All the test images on our site that are represented as being characteristic of each camera's output are exactly as they came from the camera. The sole exception is that we use a lossless rotation program to turn the portrait-format shots so they'll display correctly. This rotation (done in Juri Munkki's Cameraid(tm) program) is lossless, which means that it preserves the pixel information exactly.

You're right, if we were mucking about with what the cameras did, a major component of the site would become completely pointless...

-- Dave Etchells (web@imaging-resource.com), January 16, 2000.


Well its my understanding that the house picture on this site is a picture itself. They are simply taking a picture of a picture to see how well it resolves detail. The test images are completely honest I'm sure and are of use in comparisons. If you want real world pictures simply go to the "Other Resources" page and check out some other sites with other pictures. It would be pointless to show all different pictures from each camera,so I think the testing procedures of this site are just what you need to make an honest evaluation. Cris Daniels

-- Cris Daniels (danfla@gte.net), January 03, 2000.

"...It would be pointless to show all different pictures from each camera..." What a load of horse s--t. If the analysis by Dave Teece is true then all of these evaluations are suspect and perhaps completely worthless.

-- Bob Roberts (bob@bob.com), January 05, 2000.

After posing the original question and then reading the response from Dave Etchells I visited the site he lists and was very pleased in the amount and detail of the information listed there. It really does give a proper explanation of each test and the significance that can be accorded to each type of test. It also increased my knowledge of the importance of the different specs I read for each camera. I can now go back and compare the few cameras I am now considering and get much more out of the comparisons. Thanks for a great site.

-- Dave Teece (dteece@home.com), January 18, 2000.


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