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 Replies: 17 / Views: 5,904 |
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Pillar of the Community
United States
4038 Posts |
The last couple threads on microscope objectives made me realize I have never done an objective shootout, and in fact have never even tried some of the ones I own. So I spent some time Sat PM and Sun AM to shoot and process image stacks for 14 objectives, all shot in the range of 4x-6x or so. The shortest focal lengths were tough to get below 6x so that's where I shot them. Interestingly at least one of the 5x had lower mag than the same company's 4x at same extension, go figure. Because of the wide range of focal lengths, I did NOT take a lot of care to get the magnifications all the same so this is not a definitive comparison. However, I think the results vary widely enough that this should be useful for folks considering buying an objective for shooting varieties and other coin details. Here is the list of objectives tested. All are RMS mount unless otherwise noted. These are in no particular order: Canon 35mm f2.8-f22 Macrophoto Parco 4 0.15 Made In Germany 5x 0.1 Technical Instruments 4x 0.13 Nikon 4 0.1. Same type as tested recently by CaptainFwiffo Olympus 4 0.1 Nikon 4Plan 0.1 Olympus M5 0.1 Bausch & Lomb 48mm 0.08 Bausch & Lomb 48mm f4.5-22 Micro Tessar Canon 20mm f3.5-22 Macrophoto at f3.5 Nikon 5x Measuring Microscope (M26 mount) Zeiss 20mm f3.2-f32 Makrotar Nikon Plan 4 0.13 Canon 35mm f2.8-22 Macrophoto at f2.8  Canon 35mm f2.8-22 Macrophoto at f4  Parco 4x 0.15  Made in Germany 5x 0.1  Technical Instruments 4x 0.13  Nikon 4x 0.1  Olympus 4x 0.1  Nikon 4Plan 0.1  Olympus M5 0.1  Bausch & Lomb 48mm 0.08  Bausch & Lomb 48mm f4.5-22 Micro Tessar at f4.5  Canon 20mm f3.5-22 Macrophoto at f3.5  Nikon 5x Measuring Microscope  Zeiss 20mm f3.2-f32 Makrotar  Nikon Plan 4 0.13  |
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Bedrock of the Community
Australia
21786 Posts |
Interesting how that spot in front of the '6' shows up in different ways.
rmpsrmps: You have the coin 'in hand', so to speak.
Which picture shows the spot closest to the truth?
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Pillar of the Community
 United States
4038 Posts |
They look different because of the small differences in working distance and light placement. You can't look at that piece of dust without optics and lighting, and your choice of optics and lighting changes the way the piece of dust looks. So what is the truth? They are all the truth.
Contact me for photographic equipment or visit my home page at: http://macrocoins.com |
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Pillar of the Community
United States
4132 Posts |
I know you said all were RMS unless otherwise noted, but you didn't note otherwise on any of them. Are they all RMS? I assume the ones with photographic-style desginations (focal length and f-stop vs. magnification and NA) are more along the lines of regular photographic lenses rather than microscope objectives?
The color varies quite a bit - I assume that part of that is the changes in lighting, but some must be attributed to the objectives. They don't seem to do as good a job in this area as photographic lenses.
Of these I liked the Canon 35mm, Nikon 4Plan 0.1, Canon 20mm, Nikon 5x measuring, Zeiss 20mm and Nikon Plan 4 0.13. If I was to decide further between those I would like to see less heavily compressed images. All the others suffered badly in the corners. Interesting that both the Bausch & Lomb have a central hotspot/flare. I assume the 20mm ones from Canon and Zeiss had the shortest working distance, based on the low angle of the lighting on those.
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Pillar of the Community
United States
4038 Posts |
All are RMS, even the ones with variable aperture, except the Nikon 5x. Both Canons, the Zeiss, and the B&L are all photomacrographic objectives that are a cross between a regular camera lens and a microscope objective. They were all intended for bellows setups similar to the Nikon Multiphot. Note that I sold my Nikon 35mm Macro Nikkor (I still own a 65mm) so did not test the lenses intended for Multiphot. Canon intended you to use the Bellows FL or Auto Bellows FD with their MP20 and MP35 lenses.
I did no color correction between lenses, keeping the camera set to "tungsten" and using a pair of Jansjos, so any differences in color are attributed to the lenses themselves. The Canons and Nikons are most color-correct. The Zeiss is color-correct but more saturated than the others, typical of Zeiss lenses.
I published this on two other forums, and folks seem to really like the Canon 35mm. I was personally much more impressed with the Canon 20mm, since I was able to use it wide open and get a super sharp image. The 35mm was not so sharp at f2.8, and is OK after stopping down to f4 but that's into diffraction-limited territory, though very similar to a NA 0.1 objective. But if I have to stop down to f4 on a $300 lens, why not just buy a $50 objective instead?
You're spot on with the B&L, they both have a central hotspot. I don't know if this is flare or perhaps internal reflections, but it is definitely limiting for contrast.
I'll wait for a few more responses before I publish my personal ranking of these objectives...
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Pillar of the Community
United States
4132 Posts |
Can you provide any information on the working distance of the different lenses? Maybe not exact mm numbers, but general idea (i.e. such-and-such objective was impossible to light, this other one had lots of room).
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Pillar of the Community
United States
4038 Posts |
They fall into 4 categories:
Very short (~20mm): Makrotar 20mm and Canon 20mm. These are simple lenses and thus have about 20mm WD.
Short (25-30mm): All the standard objectives except the Nikon 4.13 and Nikon 4 0.1. The 4.13 had longer WD, while the 4 0.1 was shorter
Long (35-50mm): The 35mm Canon and 48mm B&L's are also simple lenses, so their WD was approx their focal length
Very Long (~75mm): The Nikon 5x MM has a very long WD. This gives it the unusual property of effectively being telecentric, at least for coin image stacks.
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Pillar of the Community
2087 Posts |
This thread needs bumping. Some time ago I tried to give away a minolta III bellows thankfully there were no takers. I say thankfully because the Novoflex bellows I usually use only extends to 120mm. The MInolta bellows goes to 150mm. In the post I have an RMS -M42 adapter, and a M42 to minolta adapter. I picked up a cheap(question follows) 4 times Microscope objective some time back. I just had a closer look at it and it reminds me of those cheap Adapters with so called speed boosters in them(ie: it seems to have only one lens in it). So my question is What type of Micro scope objective is best? Yes I read the shoot out.....But when it comes to buying there is a huge range in prices for example a Nikon Plan 4 0.13 is about US$200, and a Fluor version can range out to nearly US$1000. I have no idea what the difference in value means in performance. Is it like some camera lenses where a $200.00 lens will be provided 80% ( picture quality, Distortion etc) of what a $1000.00 lens. I am kicking myself regarding missing an ebay sale on a canon 20mm that went for US$200.00 recently... and I am now looking hard at a Minolta 25mm ( similar to the canon) that is going for €390.00 locally. I know if I purchased the minolta and it didn't perform as I wanted I could easily resell it but it is a lot of money!! I wonder if there is a cheaper microscope objective that would do the job for the same quality. |
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Valued Member
440 Posts |
Ray what does RMS stand for?
I'm currently using the Nikon M5 0.1 microscope objective. Is that the same one you tested here?
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Moderator
United States
56855 Posts |
I like the Zeiss best. John1  |
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Pillar of the Community
2087 Posts |
RMS = Royal Microscopal society. The society set the specifications for objectives. I believe there are other standards but the thread size for mounting, in most cases, is the same as the RMS thread
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Valued Member
South Africa
453 Posts |
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Pillar of the Community
United States
4038 Posts |
The differences between microscope objectives is much more pronounced than between camera lenses, and there are many sub - types and specialty objectives that may or may not work well for coin detail photography. As an example, the fluor objective is for good UV transmission, not required for coins. There are a few lines from a few manufacturers that work well, and outside this range it is hit or miss.
CP, I did not have any Nikon M5 available when I did this test.
Regarding the Zeiss, keep in mind it is at higher mag than most others, so might look better because of that. Sort of like testing speakers...the louder ones always sound better.
Contact me for photographic equipment or visit my home page at: http://macrocoins.comEdited by rmpsrpms
08/28/2014 3:02 pm
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Pillar of the Community
United States
4038 Posts |
AK...the M5 CP refers to is my current recommendation. Reasonable price, good performance, and OK working distance. It can be pushed from 3x to 7x with good results.
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Valued Member
440 Posts |
Thanks for the clarifications.
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Pillar of the Community
United States
4038 Posts |
Quote:...But when it comes to buying there is a huge range in prices for example a Nikon Plan 4 0.13 is about US$200, and a Fluor version can range out to nearly US$1000. I have no idea what the difference in value means in performance. Is it like some camera lenses where a $200.00 lens will be provided 80% ( picture quality, Distortion etc) of what a $1000.00 lens. I am kicking myself regarding missing an ebay sale on a canon 20mm that went for US$200.00 recently... and I am now looking hard at a Minolta 25mm ( similar to the canon) that is going for €390.00 locally. I know if I purchased the minolta and it didn't perform as I wanted I could easily resell it but it is a lot of money!! I wonder if there is a cheaper microscope objective that would do the job for the same quality. The Canon 20mm is truly excellent, but I find that I don't use mine very much. I use the 35mm more often, but the lenses I use the most are the Nikon Measuring Microscope Objectives. I like them because they have excellent resolution and phenomenal working distance, almost as much as my regular lenses. They are also superb for stacking because they are telecentric. They are fairly expensive but worth every penny. But the best bang for the buck is still the Nikon M5... Edited by rmpsrpms
08/29/2014 12:04 am
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Replies: 17 / Views: 5,904 |
Posted 01/14/2013 11:03 am
