A list of achromatic close-up lenses
In my search for high quality optics to do close-up photography with my superzoom digicam, I came across several web pages that list good achromatic lenses. These are filter mount lenses, sometimes called "doublet" or "2 element" lens or "close-up filter". On this page I'll combine those sources and make a final list. The information is taken from the following sources: Greg Erker, Bob Johnson and Ian Odgers (who in the mean time has removed his list), and a lot of my own research. I made this list primarily as a reference for myself, and I thought: "Well, if I'm gonna make an ultimate list, I might as well put it on my site!" In the end, I got 2 pieces of the Sigma achromatic macro lens, and have been very satisfied with their quality. This list was originally made in 2005, but 8 years later I'm still using them now and then with the excellent Minolta 135 mm f/2.8 tele lens and my ring flash system!
In the table head, "Verified" means that I have come across the lens myself on more than two occasions on the net, and therefor know it is indeed an achromat, and it is still being made, or at least being sold new or used. Price ranges are: Low (below USD 50), Medium (USD 50-100) and High (USD 100 and up).
|Manufacturer||Model||Sizes||Diopters (+)||Optimized for lens||Verified||Price range|
|Canon||500D ||52 58 72 77||2||70-300||Yes||Med|
|Canon||250D ||52 58||4||50-135||Yes||Med|
|Century optics||Achromatic diopter||58||2 4 7||40-300||Yes||High|
|Heliopan ||Achromat close-up||49 55 67 82||3 4 5 6||-||No||High|
|Hoya||Macro Close-Up filter||49 52 55||10||50||Yes||Med|
|Olympus||Close-up lens ||49||5.9||80||No||N/A|
|Olympus||iS/L lens A-Macro||49||2.5||-||No||Med|
|Olympus||iS/L lens B-Macro||55||2.5||-||Yes||Med|
|Olympus||iS/L lens A-Lifesize Macro ||49||7.7||-||No||High|
|Manufacturer||Model||Sizes||Diopter (+)||Optimized for lens||Verified||Price range|
|Opteka||High definition 10x macro ||52 55 58||10||50-300||Yes||Low|
|Raynox||DCR-150 ||43 52-67||4||50-300||Yes||Low|
|Raynox||DCR-250 ||43 52-67||8||50-300||Yes||Low|
|Sigma||Achromatic macro lens||34 43 52 58 62||1.6||70-300||Yes||Low|
|Sigma||Life-size attachment ||52 58 62||1.6||70-300||Yes||Low|
|Zoerk||Makroscope type I||52||12||50-135||Yes||High|
- Close-up lenses sold in sets (of usually +1, +2, and +4 and some even including a +10) are never achromatic. Imagine how much a set like that would be!
-  Canon also lists 240, 250, 450 and 500 lenses (without the "D"). These are NOT achromats
-  The high diopter, large diameters are VERY expensive (over 500 US dollars)
-  Originally intended for use with their 80mm f/4 auto macro
-  This is a 3-element lens
-  This is a 4-element lens
-  All listed Pentax lenses are intended for large format cameras, but should work just as well on any other camera
-  Originally included with older Sigma lenses before 1:1 macro capability became common for Sigma. I have seen this lens listed as both +1.6 diopter and +10 diopter. I don't know which is true, but +1.6 would be the most likely. It's probably the exact same lens as the Sigma "Achromatic Macro Lens".
-  Optimized for the Leica Summicron-R 50mm f/2 only
-  Optimized for the Leica 90mm f/2.8, 90mm f/2, 100mm f/4 and 135mm f/2.8 R-lenses
If you have more info on achromats to add to this table, please leave a comment or contact me personally. Let's make this the most accurate list on the face of the earth.
Why would you want to use an achromatic lens? I'll tell you why. What a lens (any lens) does is refract the light that's going through it. It alters the light's direction so to speak. In doing so, different colors of light are refracted slightly differently. If you ever paid attention in science class, you must remember the prism, which breaks a white strand of light into the colours of the rainbow. This is called dispersion, a physical phenomenon that occurs in all optics. The result of dispersion in photographic lenses is called chromatic aberration; color fringing in laymen's terms. What an achromatic lens does is largely counteract the refraction differences of the different colors of light by using 2 bonded optic elements with different dispersions.
On a sidenote: for some optical systems (like extreme telephoto lenses), the use of achromatic elements is not enough to get the best results. Instead, apochromatic lens elements are used. This is often abbreviated to APO. Apochromatic optical systems use elements made of very special kinds of optical material, for instance crystalline calcium fluorite, which has low dispersion of itself to begin with. Needless to say, fluorite is much more expensive than normal optical glass.
The difference between a cheap single element lens and an achromatic lens can be quite dramatic as is illustrated by the following examples. Please note that part of the difference is the difference in diopter of the two lenses.
A bar code, seen at full zoom (380mm equivalent) through a cheap single element +2.9 close-up:
The same bar code, seen at full zoom (380mm equivalent) through a +1.6 Sigma achromatic macro lens:
The difference is blatantly obvious in these brought-to-scale, 100% crops:
I don't have to explain which is which now, do I?
For some excellent examples of what can be done with a relatively cheap setup with a compact camera and achromats, have a look at Seemolf's (Sven Gude) website. Sven has done many amazing shots.
So, what focus advantage does an add-on macro lens give, exactly? It depends heavily on the lens you're adding it to. To calculate this, you first need to know the equivalent diopter of the lens you're using. This is the inverse of the closest possible focus distance in meters (to convert inches to meters, divide by 39.37). So if your closest focus distance is .82 m, then you can calculate the diopter with the following equation:
D = 1 / .82m = 1.22
Add to this the diopter of the lens(es) you're adding. For instance, my 2 Sigmas have a diopter of 1.6 each, so I'd have to add a total of 3.2:
D = 1.22 + 1.6 + 1.6 = 4.42
To convert this number into the new focus distance, calculate the inverse of the new diopter:
d = 1 / 4.42 = .226 m
If you're more used to inches, multiply this number by 39.37 and you're done.