# Macro lens basics



## niko (Jan 28, 2004)

Kenneth (cousinkenni) asked me some well backed up questions about macro photography. The response that I wrote turned out to be pretty comprehensive and I thought it may be of interest to others too. Here it is:

Here's my view on your questions:



cousinkenni said:


> 1) Buy a regular zoom lens (for instance the canon ef-s 18-55, with a filter diameter of 58mm) and just add macro rings on (+1, +2, +4, even +10)
> 2) Buy a specific macro lens (for example canon EF-50, Ef-100 or MP-E65)
> 
> I) Questions between schools:
> ...


There are 3 simple ways to make a lens a "macro" lens:
1. Add rings between the camera body and the lens. These rings are called extension tubes (or macro rings). They usually come in 3 lengths, each providing greater magnification. The rings can be used stacked together.
2. Close up lenses. These are basically magnifying glasses that screw in front of the lens (just like a filter). They usually come in 3 strengths (diopters), each providing greater magnification. They can also be used stacked together.
3. Attach the lens to the camera body in reverse - the part that accepts the filters now goes toward the body. That is a trick that requires special coupling rings and it's not doable with all lenses and cameras.

Read about other ways to make a lens a "macro lens" here.

You can take excellent macro pictures using macro rings or close up lenses Using a special macro lens produces the best results. Macro rings have a slight edge over close up lenses but not very noticeable in the final picture. So basically the list is as follows (best to worst)
- special macro lens
- macro rings
- close-up lenses

Using close-up lenses that screw on your existing lens is the cheapest option. The sharpness in the edges of the frame is less if compared to an image taken with macro rings or a special lens. Once again the difference is small, but will be visible in some pictures, especially around the edges of the frame. Jay will probably be better than me in explaining the actual differences.

I personally would try to get at least macro rings.



cousinkenni said:


> II) Questions about each school:
> A) Regular lens w/ macro rings:
> 1) Do macro rings change the minimum focus distance of the lens (for EF-s18-55 it would be .92 ft)? In other words can I get closer to the object by adding a macro ring??


Yes you will be able to get closer to the subject by adding macro rings. Same with close up lenses.

I see you know that getting closer to the subject is not that great. If the distance between the lens and the camera is say only 1 inch the lens may be too close to the subject and scare it off, shield the light, or you won't be able to get close enough. For example fish will swim away, or you will want to shoot plants that are by the back glass of the tank. Those problems are aleviated by using a lens with a greater focusing length: 
For example:
A standard lens (50 mm) with added macro ring will let you focus sharply on a 1/2 inch fish from a distance of 2 inches.
But the same macro ring used with a telefoto lens (200 mm) will let you focus sharply on the same fish from 10 inches away.

The same goes for using close-up lenses on those 2 lenses.



cousinkenni said:


> B) Macro lenses:
> 1) Is it better to get a lense (the EF-50) that can focus closer to the tank (.8 ft) or one (the EF-100)that can focus farther away from the tank (1ft)and "zoom in"? Now both of these lenses (the EF-50 with life size adaptor) can supposedly focus down to full life-size 1:1 magnification (once again I am not 100% sure what this means).
> 
> 2) Is there a benefit to getting the MP-e65 which can focus down to 1:5 life size magnification at .8ft(I believe this means 5X life size)?


1)
First be aware that many lenses claim a macro abilty that is not a true macro. Look for lenses that are labeled "Macro" after the apperture they provide a true 1:1 magnification (read below about it). In this listing the lenses labeled "macro" are not true macro lenses because they do not provide 1:1 magnification. True macro lenses are usually fixed focal length. Nikon uses the word "Micro" for their dedicated macro lenses. A macro lens can be used as a normal lens too - look at  these pictures, they were all taken with the Cannon EF 100 2.8 Macro lens.

It is best to buy the macro lens that has the greatest focus length. So if you can afford it get the EF-100. As I explained above - it will allow you to stand away from the subject and still get the same magnification. If you want to save money and get the longest macro lens your money can buy then look at aftermarket lens - a lenses - they are not made by the manufacturer of your camera but one will perfectly fit on it. In most cases the quality of the images will be the same for the viewer as the images taken with a brand name macro lens. Here's an example of such lenses. The 180 mm one will let you stand the furthest from your subject and will allow you to get the exact same picture as the 50 mm one.

"Full life size magnification 1:1) means that when you point the lens at a 1/2 inch fish the image of the fish will not be reduced on the film.(=13 mm) In film photography the size of the frame is 36x24 mm. So the image of a 10 mm fish will also measure 13 mm on the film - 1:1. Such magnification is pretty extreme but modern digital cameras with built in macro mode often have that feature.

2)
The MP-E 65 is an extreme macro lens. You will probably not find yourself using it all the time unless you get into extreme macro photography - a single scale of a fish, a developing fry in a fish egg, the eye of the fry only, etc. I think that it will be best to get a dedicated macro lens first.



cousinkenni said:


> Other questions:
> In your Sticky "avoiding image blur (1 of 3) you start off by showing one of Luis' pictures that you said was taken using a hand held camera. What kind of camera was this picture taken with? How far away was the camera from the glass? How far was the plant from the glass?
> 
> Would I be able to take such extreme close-ups as Luis' picture if the plants are way in the back of the tank? What type of lense would I need to take macro pictures of plants in the way back of my tank?


The picture of the buble in Luis tank was taken with a Nikon CoolPix 4500. That camera has an exceptional built-in macro capability. Nikon discontinued this camera quickly and the following models didn't include such great macro mode. I guess such macro capability was considered too much for the average buyer of such a camera.

When I took that picture the camera was about 1 inch from the plant with the bubble. As you now know - if I had a dedicated macro lens I could have been say 10 inches away. I was lucky that the plant was right by the glass and I could get so close to it.

Another thing about macro photography is the light. You need a lot of it. Luis uses a lot of light on his tanks. In this case the light was also close - about 3 inches above the plant. As you see everything worked for this shot I just had to point and shoot. That is not a situation that one usually encounters.

You will be able to get such close ups if the plant was in the back of the tank if you have a 100 mm or more macro lens AND if you have enough light. Also if the tank has thick glass the quality of the image will suffer. The water thickness between the lens and the plant will also lower the image quality.

Ask me anything else.

--Nikolay


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## cousinkenni (Jan 24, 2005)

Nikolai,

Thank you very much for the response!

I think you pretty much answered every question I had.

Ken


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## S (Oct 1, 2004)

Photography was the subject at the local saltwater club meeting this month. One thing I learned about macro is that on the nicer cameras it involves the ability to magnify objects but with less powerful cameras it just means that the camera focuses on objects very close to the lens. I hope I explained that right.


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