![]() Thankfully we now have smaller companies like Cosina, Sigma, and even Tamron producing better and better designed everyday and forcing Canon to update the old designs. Its not just an average performance, its one of the worst LoCA producing lenses that I own, and I own a lot of lenses. ![]() The specs include one UD or Ultra-low glass element but looking at the results you would never have guessed it judging by the amount of neon green bokeh fringing. The MP-E 65 was released in 1999, that is almost 18 years ago, but given the resources and lens design experts at Canon's disposal they could have done a better job of suppressing LoCAs on the MP-E. The Mag.x crops are some of the cleanest you will see from any objective, CA suppression on this lens is even better than Nikon Plan APOs. The Mag.x suppresses LoCAs almost completely, performing at the very highest level, unlike other lenses labeled APO, more like a Super Apochromat. The Canon MP-E 65 test crops show worse than the average CAs, especially for a lens that, according to Canon, uses UD glass. Sharpness Test CANON MP-E 65MM MACRO LENS VS MAG.X 5X 0.20 LD PLAN APO OBJECTIVE Center crop at 100% All of the images shown here are single files. All images were shot as a single RAW files and processed in PS CC with all noise reduction and lens correction turned off, all settings were zeroed out (true zero) and the same settings were used for all of the images. At 100% view in Photoshop the sharpest was chosen for center, edge and corner. Vertical stand: Nikon MM-11 with a Nikon focus blockĪ series of images was shot with each lens in 4 micron steps, the MPE 65 was also shot at each third stop from f/2.8 to f/4. 3.92 micron sensor pitchįlash: Godox TT350s wireless flash x 2 with one Godox X1s 2.4G wireless flash transmitter The simple formula for effective aperture is: Aperture = Lens Aperture x ( 1 + Magnification ) THE SET-UPĬamera: Sony α6300, model # ILCE-6300, also known as: A6300 Comparing f/12.5 and f/19.2 is a difference of more than one stop between the MP-E 65 and the Mag.x. The Mag.x has an NA of 0.20, which is a nominal aperture of f/2, and an effective aperture of f/12.5 at 5x. In the case of the MP-E 65, the resolution loss from diffraction at f/3.2 was less than the loss due to aberrations at f/2.8. ![]() ![]() When a lens has lot of aberrations, stopping down will reduce resolution and sharpness loss due to aberrations, while at the same time increasing resolution loss due to diffraction. With the 24 MP Sony A6300, the softening effect of diffraction starts to become visible at 100% view around f/8! That means that the MP-E images made here were at an effective aperture of f/19.2, which is firmly in diffraction territory. Thats not all, the effective aperture in this test is actually worse since my MP-E 65 did not deliver optimal sharpness at f/2.8, instead my lens was sharpest at f/3.2. The Canon MP-E 65, with a maximum aperture of f/2.8, seems like it would be free from any issues with diffraction, but the nominal aperture of f/2.8, turns into an "effective aperture" f/16.8 at 5x magnification. You can predict the resolution from a certain lens simply by looking at the effective aperture. At smaller apertures resolution and sharpness can suffer from diffraction, the softening effect that is caused by light dispersing or "diffracting" when passing through a lens aperture. The larger the aperture, the more resolution and sharpness a lens can deliver so a wider aperture = higher resolution. Microscope objectives have a big advantage at magnifications like 5x and higher. The purpose of this comparison is to look at the difference in image quality between the Canon MP-E 65 f/2.8 macro lens designed for the consumer market, and a more specialized lens, the Mag.x LD Plan Apochromat 5x/0.20 objective, designed for industrial electronics inspection.
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