Macro Lens

Discussion in 'Photography Equipment & Products' started by kiwiluke, Jan 14, 2007.

  1. kiwiluke

    kiwiluke TPF Noob!

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    I'm just about to get a new 400d and am interested in getting a macro lens for it as this is one of my main photographic interests, any advice on the pros and cons of the various macro lenses on the market would be apreciated. I'm not looking at top of the line as my budget won't strech that far but more of a good all round marco lens
    Thanks
    Luke
     
  2. Digital Matt

    Digital Matt alter ego: Analog Matt

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    What do you plan to photograph? There are lots of different options for magnification of an image, and depending on what you photograph, you might need a 100mm macro, a 180mm macro, a 50mm macro, extension tubes, or just closeup filters.
     
  3. SaSi

    SaSi TPF Noob!

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    Your options, in order of quality achieved, are:

    1. Close up lenses
    2. Extension Rings + any lens (e.g. kit lens)
    3. Reverse mounting of the lens
    4. A real macro lens (like the EF-S 60 or EF 100)

    The close-up rings are cheap and quick to do some close-up work giving close to macro (1:1) reproduction. They suffer from severe chromatic abberation and distortion, especially as you move off the center of the frame. Canon branded and high quality close-up lenses are much better, but still the worst aproach.

    Another side effect of close-up lenses is that they shift the focus distance very close to the lens. The stores advertise this fact as great, however it is not. Working distance is reduced and so is comfort.

    Extension rings are added between the lens and the camera, and they shift the minimum focus distance closer to the lens while at the same time increasing the magnification. Since there is no glass, optical quality is not reduced. Actually it is "enhanced" as the working area of the lens is the center part of it, where all lenses (even cheap ones) perform best. The amount of light entering the camera is reduced as the extension length is increased, which is not an issue for metering (it's handled by the camer) but the viewfinder gets darker.

    There are autofocus extension rings in the market (Canon + Kenko) and they are expensive. There are dirt cheap extension rings that fix the lens in manual mode, which is not bad since the camera can evaluate light and work in Av mode.

    The kit lens needs a lot of extension before it reaches close to 1:1

    A reverse mount adapter for the lens creates a magnification lens. Magnification is very high (compared with the normal orientation of the lens) however if you reverse mount a mediocre lens, the results will be inadequate.

    There are other combinations there, like mounting two lenses facing each other with one (telephoto) on the camera and a reverse mounted one (wide-angle) in the front. These combinations are fun (provided you have all the required rings, converters and a lot of patience).

    Results can range from awful to good, however the increased magnification as well as twice the glass (in case you mount two lenses) generates a lot of CA.

    Then, there are the macro lenses. I've played a lot with the other options in the past and created the misconception that macro photography is hard. Then I bought myself an EF100/2.8 macro. What a joy!

    You can hand hold the camera and do macro. Working distance is pretty good at more than 20 cm, allowing even the built in flash to be adequate in most cases.

    Optical quality is superb, both for macro and portaits.

    You can combine the macro lens with extension rings for even higher magnification (so the rings become a very cheap start-up, even with the kit lens).

    A ring flash will become the natural accesory of this setup, once you get hooked in this.

    The question for me is, actually: Which macro lens?

    There are three models from Canon. I can safely assume the EF 180/L is out of your budget (and mine), although it is a superb lens with great working distance. (Working distance is the hidden secret in macro and increases as the focal length increases).

    Then there are the EF 100 and the EF-S 60. Their price difference is not high and the EF-100 will double as a full frame lens. It is more expensive and offers a longer working distance than the EF-S 60, and these are the two reasons why I chose the 100.

    There is also a 70mm macro from Sigma. It's good and priced in the middle between the two Canons. But I've heard so many good things about the EF100 that I didn't bother with the other two.

    If the EF100 seems to expensive, I'd recommend the EF-S 60. It's also a great lens and cheaper than the Sigma, and since its only 10mm shorter, the working distance between the two should be similar. You could be saving about $250 towards a flash unit.
     
  4. fmw

    fmw No longer a newbie, moving up!

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    Let's see if we can add some information here.

    It is possible to buy closeup lenses that are corrected for chromatic aberration. They are two element lenses and cost less than $100. We call them achromatic closeup lenses because they are color corrected. Canon and others have these available and they work quite well - for me they work better than extension rings or anything other than a macro lens. I use one with my macro lens from time to time with excellent results. I agree that the single element ones are poor performers. Achromats have an additional advantage of causing no light loss, unlike any other of the options (including the macro lens.)

    As does any close focusing device, including macro lenses. Working distance is a function of focal length. Reproduction ratio is a function of focal point.

    Extension rings don't increase magnification. They simply move the lens away from the camera body so that it will focus closer but no longer focus at infinity. There is no "enhancement" of any kind. They extend the entire lens, not just the central part of it.

    It creates nothing. It simply turns the lens around around backward so that it will focus closely but no longer at infinity. In my experience this is the most difficult kind of device to use because there is very little working distance. Also the resulting reversed lens is very slow in comparison to the same lens right side out because the smaller rear element becomes the front element. Mediocrity in a lens is no different in either forward or reverse. I put it at the bottom of the list. On the plus side it is possible to get reproduction ratios above 1:1 depending on the focal length of the lens.

    ......and don't care about image quality.

    Macro lenses have a very important feature known as flatness of field. When you are working up close, the difference in focus between the center and edges of the frame is very noticeable. Depth of field can improve things but only to a degree. Macro lenses suffer from some of this as well because the primary lens elements in every lens are spherical. However, the effect is less pronounced than it is with a standard lens. While macro lenses do not perform quite as well as standard lenses at infinity they perform very much better up close thanks to a flatter field.

    Personally, I recommend against lens reversing devices and extension rings. The former are fussy to use and the latter bring out the worst in the lenses that are normally used with them. Small extension rings used with macro lenses work very well. Large ones used with standard zoom lenses work pretty badly - to be fair, I'll just say they don't work as well as achromats.

    If you can't spring for a macro lens, which would be the best option, then go buy an achromatic closeup lens and amaze yourself with how effectively they work. If you plan to buy a macro lens in the future, then buy an achromat in the same filter size so you can use the two together.

    I use achromatic closeup lenses with medium format. I've done catalog covers and magazine spreads with them.
     
  5. kiwiluke

    kiwiluke TPF Noob!

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    Wow thanks for all the indepth info, i'm definately looking at getting a true macro lens, i'm most interested in shots of small wildlife, ie small insects and the like as well as plant detail and close up shots of everyday objects. At the moment i'm thinking i'll save for the canon EF 100mm (the 180mm looks amazing but so is the price and the bank manager tells me it aint gonna happen!) I purposly kept my ideas out of the original question as i didn't want to influence peoples answers. I think i'll have to get too close if i use the 60mm lens and could risk scaring any creature away if i shove the lens that close to them. Anyway thanks for such indepth answers
    Luke
     

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