Buying a macro (WIP)

This guide to macro lenses is still a work in progress, but I figure that the best way to get it finished is to post it as it currently stands. Comment is welcome and may be incorporated in the final version.

The impetus for starting to write this item came from Anssisa, who both suggested it and came up with some notes to get the ball rolling which are included along with my own observations: a big thanks to him. Naturally this leads to some duplications, which we hope readers can forgive.



One of the most-often asked questions in this and other forums dealing with A-mount lenses is “Which is the best macro lens?”



The answer, in a simplified form, is “All of the ones you can afford, plus the few that you think you can't afford.”

Anssisa wrote: Sony/Minolta has a quite good support for macro, at least when choosing lenses. The common thing with macro lenses is that every one of them will give stunningly sharp pictures. Most of the lenses that are "true" macro lenses are 1:1 in magnification ratio, meaning that 1cm in real life is projected as 1cm on the sensor. So if you have or have seen zoom lenses that say macro, they are not really dedicated macro lenses with macro capability, more likely is that they have amazingly short MFD (Minimum Focus Distance) for a specified focal length. So if all these "true" macro lenses give the same magnification, what's the catch with different focal lengths? The answer is working distance. With a 50mm lense, you have to be ~1cm from the subject to achieve 1:1 ratio, when on a 200mm lens the distance can be 50cm. And that is a huge difference!

Nearly all contenders from the main stable of A-mount lens makers can be rated as being in a narrow band between very good and excellent. Check our reader reviews for macros and you will see nearly all have an overall rating that is over 4.5 out of 5.



Basically the choice comes down to a mix of new and second hand lenses that includes: 50, 100 and 200mm lenses by Minolta and Sony; 50, 70, 105 and 180mm lenses by Sigma; 90 and 180mm lenses by Tamron; and the Cosina 100mm “plastic fantastic. Even the latter would have a reader rating over 4.5/5 were it not for its somewhat light-weight build.



One of the first independent surveys of a group of macro lenses I ever read (it's no longer on the web unfortunately), began with the statement that no manufacturer makes a bad macro. Maybe the author had not encountered the Voigtländer AF Macro Dynar 100mm or the Tokina 100, but these are the only major exceptions to his rule that come to mind, going from their reviews.



One of my “qualifications” for writing about macro lenses is that I have owned five and still have three. At one time I had in my possesion a Minolta 50 (RS)*, a Tamron 90 (72e)*, a Minolta 100 (Orig), a Sigma 105 DG and a Sigma 180 f5.6 APO*. The asterisks indicate those still in my kit. The Tammie is my second, since I sold my first and then began to regret that decision so much that another was needed to quench lens lust. I have also read and contributed many threads about macro photography at DPR and here in Dyxum.

Anssisa wrote: STEP 1: Decide what you want to use your macro lens for. Usually macro lenses are used for shooting flowers, productshots, insects, documentation purposes, or taking portrait pictures

If you are looking for your first true macro lense and have an APS-C dSLR then focal length becomes your first consideration, with that 1.5x crop factor – the 50mm lenses become 75s, the 90s become 135s, the 100s become 150s and the 105s become 157s.



There's actually an advantage from being able to stand back a bit from your subject, particularly if it is an angry bee, or a wasp. But portraiture can still be accomplished successsfully with anything in the 135 to 157 equivalent focal length. So the “safe” recommendation for focal length is a “true” 90-105mm. You should also note that the 150 and 200mm macros are normally significantly more expensive and they are normally f3.5-f4.

Anssisa wrote: STEP 2: Decide what focal length will be best suited for you. *50mm is good for closeups and documentation, flowers and can be used as a normal 50mm. At the moment Sony/Minolta does not offer a wider macro than 50mm. *70mm is a good compromise between 50mm and 90/100mm. If portraiture is one thing that is also wanted to achieve with the same lens that is used for macro, 70mm can be better suited for you, depending on your style. *90mm/100mm/105mm is the "standard" for macro lenses, and is good at everything. It gives enough working space between your subject to enable shooting small insects without scaring them, and works like a portrait lens also. *150mm/180mm/200mm These lenses are already a bit long for normal portraiture, at least for most indoor shots. As macro lenses they will give great working distance and are ideal for bugs. Due to slow AF, these can not double as birding/sport lenses even if focal length would normally allow for it.

Some recommendations



Based on my personal use of five macro lenses, I have no hesitation in recommending three “best of class” in the 90 to 105mm category, and I place then in the following order – the Tamron 90mm (from the 72e model on); the Minolta 100mm (from the RS version on), or its Sony equivalent; and the Sigma 105mm (EX and DG EX).



The Minolta 100 original model does not have circular blades. Their introduction with the RS model helped to provide the top-quality bokeh that narrowly separates this lens from the Tamron and Sigma lenses – both of which, it needs to be noted, also have good bokeh.



To this three, add the Cosina 100mm f3.5. OK, so to get 1:1 it needs to be fitted with an adaptor, but it is actually rare to use any macro lens in the field at less than 1:2. On a “bang for buck” scale it should be seriously considered by anyone looking at a dedicated macro for only occasional use.



Other focal lengths



At the shorter focal length end, I can heartily recommend the Minolta/Sony models (again from the RS model on) and the results I have seen from the Sigma 50s show that they warrant the high scores given in our user reports.



Some say that the Minolta 50 macro (RS) is the sharpest lens in the 100mm and under category ever to come from the mind of Minolta.



A relative newcomer in that category is the Sigma 70mm f2.8 EX DG – it is well worth investigating and some may find appeal in a focal length with the obvious dual-use application of portraiture.



At the longer end things can get rather expensive, but many swear by their 180mm macros and the 200mm f4 APO macro by Minolta is considered to be one of the “greats”.



Provided you can bring plenty of light to bear on your subjects, and provided you can find a secondhand example, the Sigma 180mm f5.6 APO maco is a surprise package in the same way as the Cosina 100. It's about the same length and weight as the Tammy 90 and Sigma 105, crisps right up at f8 and has very good bokeh.



TBC

EDITED: I have rearranged my order of preference in the 90-105 class in favour of the Tamron because its bang for buck tips the balance in its favour, especially now that used Min 100s are going for ridiculous prices.




Edited by brettania - 13 June 2012 at 05:48

!!

For further reading we suggest chthoniid's Getting More from Macro which looks at tubes, reversing, etc.

Edited by brettania - 08 January 2009 at 20:34

AF speed is a potential concern if a macro lens is to be used for portraiture. I found that the AF speed of Minolta 50mm/2.8 RS Macro is acceptable, but the 100mm/2.8 is way too slow and hunts very often. Of course we can always switch to MF, but it would be nice if Sony can make it faster.

Would SSM help in this case? Canon 100mm/2.8 USM Macro seems to be praised a lot for its focusing speed.

nice spiel bretannia & anssisa!- just when I had forgotten about longing for the tammy 180 (that can actually be had for 560USD new with shipping these days....) anyways great info - wished I had that available when I was looking for a macro

Thanks and your point is taken Jim -- it will be used in the update.

Great article Brettania, and great advices!
Thanks for the work