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Old Mar 8, 2003, 11:15 PM   #5
shene
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Join Date: Oct 2002
Posts: 579
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Quote:
Originally Posted by shiggy
I am merely providing topics of discussion that I find interesting and would like to know more about and think that other newbies might find interesting also. I apologize if my questions have put you out in some way. I don't appreciate the troll comment but I will take your opinion into consideration and stop posting much.
Shiggy
This is a good question. But, I don't know the actual intention of your question. Are you asking the way of using the macro mode of your camera or the way of a camera lens handling macro photography. They have different answers of course. So, let me assume you know how to use the macro mode of your camera and only talk about its main purpose.

A typical photographic lens is designed to produce sharp images in some focus distances. In fact, most of them can handle very well when the subject distance (the distance between the camera and the subject) in mid-range, say from 3 ft to 20 or even 30 ft. Farther than the maximum designed distance, the lens can still perform well, but will not be as good as when it is used in the mid-range. If the subject distance is shorter than the minimum focus distance, the lens will fail to focus.

As we all know, if we get the camera closer to the subject, the image of that subject will be larger on the image. But, how large is large enough? There has to be a standard way, and this standard way is the so-called magnification. Suppose the length of a subject is L and the length of it in the image is K. The magnification of the lens being used is K/L, which is usually less than 1. If the magnification is in the range of 0.1 to 1.0 (resp., 1.0 to 50.0), we will say we are doing close-up (resp., macro) photography. More precisely, if the length of the subject in an image and the length of the subject are EQUAL or even larger, we are doing macro photography. Thus, with macro photography we will be able to see the very details of an object just like a high magnification microscope can reveal the unseen micro world.

Almost all consumer level digital camera cannot do 1X, or 1:1, macro photography due to the fact that their lenses are designed for general purpose. To achieve excellent macro result at 1X, one need to switch to SLR systems. Most SLR macro lenses are single focal length lenses with focal lengths 50-60mm, 90-105mm and 200mm and can achieve 1:1 without any accessories. For consumer digital cameras with the macro capability, one can use close-up lenses to achieve 40% to 80% actual size close-up photography. Of if your camera lens has a filter thread, you can also mount a 35mm SLR lenses reversely for nearly 1:1 macro photography. If you are interested, take a look at the Close-Up page of my Nikon Coolpix 2500 User Guide for a little more details. The reverse lens portion is not available at this moment but will be added soon.

Hope this helps.

CK
http://www.cs.mtu.edu/~shene/DigiCam
Nikon Coolpix 950/990/995/2500/4500 user guide
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