I like LOMO - no detergent, no lemonade but simply the "Leningrad Optical Mechanical Union" or "Leningradskoye Optiko Mechanichesckoye Obyedinenie.
has But now, "Russian Quality" is not always the best reputation, and if now Lomo microscope e jahrela ng about the company were sold Bresser, this is not exactly ruffördernd.
This should also be the reason why LOMO now no longer sold in Europe but, somehow paradoxical, especially in North America, a ctive .
see http://www.lomoplc.com
Zeiss and Lomo are way geschi tied in nightly and the LOMO Microscopes are actually reproductions of Zeiss microscopes - see: http : / / www.microscopy-uk.org.uk/mag/artsep06/iw-LOMObiolam.html
Many amateurs, who has often Russian-optical products used know, some of which excellent performance of these products and some even dare to say this: see: http://www.novacon.com.br/lense s08.htm
In German-speaking countries, where state Zeiss the tone, you will get to hear loud approval, however rare - and so many LOMO fans hide at home and enjoy your microscopes little money and see but also what shows the Zeiss phase contrast DF-A-Plan-Neofluar -Infinity-corrected lenses so
perhaps not as planned, perhaps on a smaller field of view and sometimes with little tricks - but you can work with Although LOMO Microscopes in Europe are no longer marketed n.
, so there are a wide range in the second hand market, and so con I nte with a microscope to 70Euro Binotubus, Monotubus, large mechanical stage, some obj ective (8,20,40,90), simple electrical lighting (the ampe with Kühlschrankl ) purchase.
few months later I bought on ebay again a 40 and a 90 lens - not because I really needed - no, simply because they were so cheap!
Especially interested me, the older 40's objective, which was yet to be absorbed without any protective cover glass that is so.
Now what do these two lenses for the equivalent of three beers?
For testing I used a test product by Klaus Kemp - this preparation contains eight diatoms with different fine details.
Two diatoms, which can be found on the test plate, Pleurosigma angulatum and Amphipleura pellucida.
Pleurosigma serves as a test object for the 40x objective and Amphipleura is a milestone for the 90 lens.
the 40s and Pleurosigma angulatum: to
To resolve the fine details of Pleurosigma en complete can the lens should have a numerical aperture of at least 0.6.
Practical experiments confirm this: http://www.microscopy-uk.org.uk/mag/artsep08/dw-pa-test.html although the details vary sometimes distinguished:
http:/ / www.mikroskopie.de/mikforum/read.php?1, 23046.23046 # msg-23 046
not always the structure of Pleurosigma Making it as easy to see - but you have to do it and even with a biological object with different wavelengths of light, with different condensers u nd lighting and not so good lenses perhaps http://www.mikroskopie-forum.de/index.php?topic=1657.0
The LOMO 40 lens, however, had no problems, the fine details dissolve the Pleurosigma:
This photo was taken with the Okularkamera DCM310, stacked, several recordings with the program astro stack and finally gimp something screwed around on the contrast.
For the 40s, the Lomo Pleurosigma no real challenge, as even more for the Okularkamera DCM310, therefore still the contrast experiments with gimp.
the 90s and Amphipleura pellucida:
The fine structure of Amphipleura pellucida is s chon a real challenge to the Lomo lens 90.
The striation is only by using several tricks to make it visible:
Strong blue light, oblique illumination and a immerge FOURTH condenser.
is used, the normal condenser with 1.2nA
With what intervals you have to do it now with this diatom? - To measure a line down the length of the line surveyed and printed the whole thing: 
This results in 78 lines at a length of 21.3 microns: 21.3 / 78 = 270 nm. Since seem to have the light and dark bars the same width, I simply halve the 270 to get the distance between the dark bars: 135 nm.
If we now calculate the resolution of the Lomo 90 lens:
numerical aperture lens: 1:25
numerical aperture condenser: 2.1
Used wavelength: ~ 440 nanometer
yields: 440 / (1.25 +1.2) = 180 nm .
180 nanometers are still significantly more than 135 nanometers, hence the need for "Oblique Illumination" to use!
The calculated distance between the lines of me, fits very well with the values in the following article: http://www.microscopy-uk.org.uk/mag/MT-articleR5.pdf
Not bad for a lens 4 Euro on Lomostativ - whether an "A-Plan 100x / 1,25 Oil by Zeiss is a more than hundred times better picture as well promise the price?
Unfortunately I can not try it because I do not have such facilities already - but I must continue to dream of a lens with fabulous ;-) More power
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