Achromatic Lens

[SkinHead]

hi everyone!
Investing into "Macro" equipment doesnt come cheap, i must admit. I am particularly interested on the Sigma Achromatic lens which i can just pop into my ZD 70-300 mm. is this the same lens that came with set of close-up filter lenses which i already have, the one labeled "MACRO"?

this is the ebay link for reference:

http://cgi.ebay.co.uk/Macro-Close-Up-Lenses-for-Olympus-E400-E410-E500-E510_W0QQitemZ350190541124QQcmdZViewItemQQptZUK_CamerasPhoto_CameraAccessories_CameraLensesFilters_JN?hash=item350190541124&_trksid=p3286.c0.m14&_trkparms=72%3A1690%7C66%3A5%7C65%3A12%7C39%3A2%7C240%3A1318

thanks

[PaulE]

Re: Achromatic Lens

An achromatic lens is a lens that consists of at least two glass elements rather than a single glass element as will be the case with the ebay examples you link to. Achromatic lenses are mostly made to much higher standards than single element close up lenses and although they do much the same job (increase the magnification at a particular distance from the subject) the achromatic lenses by design (and build / material quality) will produce far superior results (less distortion less chromatic aberration etc). Having tested both cheap ebay close ups (probably the exact same ones you linked to) and more expensive achromatic close ups I can tell you there is a massive difference, the ebay ones were next to useless - I'm sure you'd get just a good a result taking a photo through the bottom of a pint glass. The achromats were useable, at least the camera would actually autofocus with them! but being used to the 35mm macro I was quite shocked at how poor even they were. The Sigma is likely better than the achromats I tried and I've heard them mentioned a number of times on several different forums as being good, I also seem to recall a Canon brand? close up dioptre being praised by a few people too, maybe someone else will be able to shed more light on them.

Due to the far higher quality of the achromatic closeups they will always cost more than the simple single element designs but I doubt anyone who has used both would recommend getting anything other than a decent quality achromatic close up if you really are intent on using them in preference to a real macro lens.

[PeterD]

Re: Achromatic Lens

hi everyone!
Investing into "Macro" equipment doesnt come cheap, i must admit. I am particularly interested on the Sigma Achromatic lens which i can just pop into my ZD 70-300 mm. is this the same lens that came with set of close-up filter lenses which i already have, the one labeled "MACRO"?

this is the ebay link for reference:

http://cgi.ebay.co.uk/Macro-Close-Up-Lenses-for-Olympus-E400-E410-E500-E510_W0QQitemZ350190541124QQcmdZViewItemQQptZUK_CamerasPhoto_CameraAccessories_CameraLensesFilters_JN?hash=item350190541124&_trksid=p3286.c0.m14&_trkparms=72%3A1690%7C66%3A5%7C65%3A12%7C39%3A2%7C240%3A1318

thanks

http://e-group.uk.net/forum/showthread.php?t=5197

The problem with ordinary single element lens is that the image projected onto the sensor cannot bring all the colours in focus together due to difference in light wavelenths. The double element achromatic lens corrects for this.

I would recomend finding the Sigma Achromtic. It is a cheap way into Macro, it does not affect the cameras ability to AF. The only thing to watch is that there is a minimum and maximum focusing range (window) for any given focal length when using this lens.

Peter

[Barrie Norman]

Re: Achromatic Lens

I can confirm with Peter as I have tryed a set of these filters off ebay and relegated them to the scrap box the sigma achromatic is a totaly differnt thing all together. You would not be happy with the results. keep an eye on ebay for the real thing.

Barrie

[SkinHead]

Re: Achromatic Lens

Thanks for all the input...have a nice weekend everyone!

[peak4]

Re: Achromatic Lens

Personally I have no experience with the Achromatic ones, but can confirm thet the single element ones leave much to be desired. Used them once and never again.

This site is well worth a look
http://fuzzcraft.com/achromats.html