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There seems to be lots of opinions about macro capabilities of the camera based on the assumption that you need 2-3-4 cm (1-1.5 inch) minimum focus distance. Of course, I might be wrong, but I absolutely think this is not the true. Ignore my 20+ years pro experience and read my explanation why I claim 2-3-4 cm is pure digicam marketing fraud which does not tell anything really useful and comparable. Please, never assume that 4 cm magnification on one camera will cover the same area and give the same magnification as some other camera from the same distance (as e.g. ones from this article).

First, please note that such (2,5 cm) numbers are available only on digital cameras since on all film cameras you actually measure distance from the film. Simply that is the measure to take.

I have two digital cameras by me at the moment. One can focus to the 4 cm and other to the 20 cm minimum. Woow, I can see many of you drooling, this other camera can focus to 5 times closer (actually at 1/5 the distance) than the first camera! But, it is not the lens that takes picture but the film (chip)! Both of these two cameras are from the same manufacturer.

Since there is no mark of the film plane on digicams as on film ones, let me assume that the film plane in digicams is 2 cm from the back. Lets now take measurement including the length of the lens and thickness of the body of the camera. Camera A is 4 cm long (deep), plus 20 cm minimum focus distance gives 24 cm from the film. Second camera is 8 cm, plus 4 cm gives 12 cm from the film.

What do you say now? Imaginary "5 times better drool magnification" factor just jumped from 5x to only 2x! All the suddenly, second camera does not look sensationally better than the first one?

Did I mention that I am willing to bet you will bump your lens to your watch several times when you try to shoot from 2-3-4 cm? I do not want to hit my lens with my watch or anything else.

We never discussed actual captured image sizes. On analog cameras, you will never ask how close can a lens focus, but you would ask about its magnification factor. Macro lenses are ones that can capture image on the film that is smaller on the film than in reality. This means, e.g. factor 1:2 - the watch will be half its real size when measured on film. Micro (as opposed to the macro) lenses will actually enlarge object, so they will be e.g. 2:1 or they will make object on the film twice its actual size. So, for a film camera, you would buy a lens that makes 1:2 macro factor, and then, you would ask about focusing distances to suit your needs. Typically, if possible, many pros would look for some 30-50 cm free space at desired magnification due to several reasons (lightning, depth of the field, ease of reflection control - not only lights, camera reflects from the object also, when further - smaller problem). Translated to digicam lingo (due to many different "film" sizes): In digital cameras, we should look for minimum capture area.

First (20 cm) camera can capture area about 5x7 centimeters (2x3 inches). That we can compare. As I said this other camera has about 2 times closer focus distance, in reality I could capture area about 3x4 cm, about two times stronger magnification.

But, camera with larger magnification has 3 MPixels and one with smaller magnification is 4 MP. If I crop 4 MP to 3 MP, I will bring enlargement size to about a half difference (1,5x instead of 2x difference) of the starting one. If we factor that the first camera has much sharper lens, difference in magnification factor becomes totally unimportant.

Now, for the big question: if my watch is 4 cm wide, and I want to capture bit of space around it and my band, why to hell do I need macro lens that can capture 3x4 cm? I do not need it and I do not know about you.

If I wanted 10 times larger magnification than these mentioned here, I would use different techniques, on both cameras the same.

Bottom line is that I am taking a photo of my watches from some 20-30 cm or more if they are in an ambient, I use focal length about 60-100 mm (in 35 mm units). By, the way, my camera makes largest magnification when set to about 50 mm, and not on 35 mm. So, If I make best pictures from 20-30 cm, who can explain me why would you need 2 cm macro focus distance? Almost any camera can focus down to the 20-30 cm.

To let you judge for yourself, here are pictures illustrating this article. Choose for yourself, which picture would you like to post! Then check the distance it was made from.

Largest magnification (camera B) shot from this camera using its minimum 4 cm lens-watch distance covers bit over 3x4 cm area:

Largest magnification (camera A) shot from this camera using its minimum 20 cm lens-watch distance covers 5x6.7 cm area:

Crop made from an actual picture shot from 20 cm with the camera A, with its largest magnification at 50 mm (in 35 mm units) sized to 640x480 as all the others. This gives larger magnification than the whole frame shot from 4 cm distance with camera B and will be enough for smallest details for the Web. Ignore low quality, I was lazy so I just snapped it with the flash on my camera :) which is something you never want to do. Look only the magnification.

My preffered magnification factor (camera A) for watches would be made by lens set to 60-100 mm (in 35 mm units), shot from some 20-30 cm. It gives me perfect control of the situation and sharp pictures.