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Achromats Part 2
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The following content was part of an old comparison. Comparing usual achromats to exotic parts. __________________________________________________________
Beginners in the macro world would like to see comparisons between cheap close up lenses and achromats. They should consider to buy a used achromat and not a single lens - close up lens. If you have some old +1, +2 and +4 lenses you should use them (f:8 or more!) until you start to hate the soft corners.
All my macros were taken in aperture mode (f:8), with fixed focus - simply adjusting the distance to the object. Most critters are too fast to use a tripod. Sometimes continuous shooting helps to get at least one picture in focus. In the beginning I could use one of 50 shots.
Some achromats can be combined if there is a front thread (shown in the table above). Good combinations are: nikon 3T,4T or 5T,6T; sigma and nikon, minolta and olympus. I prefer minolta lenses (#1,#2) in this case: 55mm thread on both sides!
Here are results from my tests - comparing achromats with closeup lenses and the achromatic lens of a russian binocular: MBS-10 - LOMO.
All the tests were made with a Panasonic FZ5.
The camera was adjusted in 12* Zoom Macro Mode to minimum distance (77cm) and then switched over to Amode F/8,iso100,fixed focus.
Testmap was my LCD-Screen with an excel sheet (arial10 fat). Two boxes in this sheet match exactly 1cm on the screen.
So everybody may compare his/her equipment to these settings.
Pictures were not sharpened just resized.
First some examples:
The wide angle closeup at 3cm is out of spec.! This is only a demonstration what happens if you get too close to the lens:0cm macro mode
The fz5 will not show such a distortion under any other conditions.
The tele macro zoom shows a field of about 8,5cm*6,5cm.
Last example shows what you get if you buy a cheap "macro" wide converter on holidays (long ago!).
from the left to the right: diopt., distance front lens- object, lens
0,0d 77cm FZ5 macro zoom 12* 77cm distance
0,0d 3cm FZ5 closeup zoom 1* 3cm distance
15d 4,5cm macro lens from cheap wide converter
Achromats - big butterfly size
good results, no distortion
1,7d 34,5cm Leitz elpro VIIa achromat
1,7d 33,5cm Sigma achromat
2,0d 31cm Minolta No.1 achromat
Achromats - butterfly size
good lenses
2,5d 27cm Olympus amacro achromat
2,5d 26,5cm Leitz elpro VIa achromat
2,5d 24cm Olympus Mcon40 achromat
Achromats - small bug size
Differences appear, canon 240 (an old lens) is fairly good, the elpro VIb (the elpro2 is the newer version of this lens) is not sharp to the edges.
The MBS-10 190mm Lens is leader in class!
4,5d 19,5cm Canon 240 (not 240d)
4,9d 15,5cm Leitz elpro VIb achromat - the previous version of the elpro 2
Not sharp to the corners
5,3d 13cm MBS-10 190 Lens excellent
Achromats - ant size
My best lens - olympus gets companions. The russian lenses are sharp to the edges.
But it is a hard job to find the focus!
7,7d 10,5cm Olympus alife size achromat
11d 8,5cm MBS-10 90 Lens
22d 2,5cm MBS-10 90 Lens with 2* extender
Closeup Lenses
The +4 closeup Lens has the known problems: soft at the edges (which is quite nice in flower pictures).
But the +1,+2 and +4 lenses reveal still an acceptable picture.
My variable and +10 diopt. Lens will retire!
4,0d 19cm Closeup Lens +4diop. rowi
2-6d 5,5cm Variable Macrolens +6 diopt.
10d 6,5cm Closeup lens
There may be better results with different cameras, zoom and/or focus settings!
Conclusion:
Most achromats and the MBS-10 lenses give good results in this test environment.
There is one exception: the Leitz elpro VIb is only sharp in the center part,
this lens was calculated for a 50mm Lens, it seems not to be suited for the extreme zoom environment.
I have seen excellent sharpness with the elpro 2 lenses, but there was no chance to judge the corner sharpness.
Among the "cheap" lenses only my closeup lens +4 diopt. gave fairly good results, the others were close to a catastrophy!
You will be missing the most popular lenses Nikon 3T .. 6T, Raynox 150d and 250d.
These ones give good results anyway. I could only test the lenses mentioned above.
My personal conclusion is, that I will start to use the MBS-10 lenses for extreme closeups.
The early plumber edition for my nikkor 50mm f/1,7 in retro position - You will find a better attachment in the "trips and ticks" section.
I have ordered a male male macro coupler for this lens now.
The MBS-10 90mm with 2*extender is much better concerning corner sharpness and vignetting.
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MBS-10 90mm lens with 2*extender (45mm)
Testing the limits: max. field of the mbs-10 using Panasonic FZ5
The mbs-10 lens covers the range from the big butterfly to the ant class, there is little correctable distortion on lower magnifications. The sharpness covers the whole range. The only problem is it´s weight. This combination will stay stationary for me and I admire CerambyX for carrying it around.
This lens is not a "normal" achromat, it can be reverted!
11d 9,5cm mbs-10 90mm zoom 3*
11d 4,5cm mbs-10 90mm retro zoom 2,4*
30d the other limit: 4 lenses combined digital zoom
...but this is not the end, you can get closer with enlarging lenses
the right side shows the surface containing the liquid crystals.....
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So we have arrived the microscopic area, but there is more DOF with
this kind of setup!
+20 diopters - 50mm componon lens reversed
+30 diopters - 35mm rodagon lens reversed
more than +40 diopters - 4* microscopic lens
This can be used for flat technical objects, but the small DOF his horrible in normal photography. With these lenses only parts of the eye of an insect are in focus.
Stacking
well, it can be done, but.....
This is expensive nonsense! Even stacking two lenses can be too much.
A typical mismatch: canon240 and minolta #1
This can be done: minolta #1 and olympus mcon40
This is good match too: nikon 3t and 4t
..and let's look at the expensive Elpros:
Elpro VIa and VIb (equivalent Elpro 1+2)
Elpro VIb and VIb (equivalent Elpro 2+2)
Elpro VIa, VIb and VIb (equivalent Elpro 1+2+2)
We are close to the quality of a single +10 diopter lens now!
The spherical aberration is no longer controlled by this combination.
Reversing the leading lens helps in this case!
This is demonstrated on the previous page
I am carrying 3 achromats with me most of the time and will not stack them.
Thanks for visiting my pages! Have a nice day - Sven
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