40-60 X Objective lens
Moderators: rjlittlefield, ChrisR, Chris S., Pau
40-60 X Objective lens
Hi every one,
I am planning to buy an objective lens with 40-60 X range, and I found this in eBay
https://www.ebay.com/itm/Seiwa-Optical- ... 264488440
is it a good lens for the price ?
I am planning to buy an objective lens with 40-60 X range, and I found this in eBay
https://www.ebay.com/itm/Seiwa-Optical- ... 264488440
is it a good lens for the price ?
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Re: 40-60 X Objective lens
Priced a little low, but it is probably not what you want. These are the super long working distance variety and have resolutions that are too low for photography at thst magnification.
Hard to know how good Seiwa's objectives are, not many test reports and iirc results are mixed.
Hard to know how good Seiwa's objectives are, not many test reports and iirc results are mixed.
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Re: 40-60 X Objective lens
Price is ok, but that's a 50x with an NA of 0.4, pretty low. You do get longer working distance, but a 50x with an NA of 0.7 is long enough for off-axis epi-illumination. If you have a Mitutoyo 20x normal M Plan which has an NA of 0.42, you will get essentially the same pictorial results by pushing it to 50x with a longer tube lens.
Seiwa objectives have mixed opinions. Based on what I've seen, it's not too good.
Seiwa objectives have mixed opinions. Based on what I've seen, it's not too good.
Re: 40-60 X Objective lens
Any options for the same range ( and good price )
Re: 40-60 X Objective lens
It needs complementary aberration corrections done at a dedicated compensating eyepiece, so they only would be convenient with the adequate microscope, not for macro style work. More recent Olympus UIS and UIS2 series (UMPL... or LMPlanFL marked) don't need them.iHasan wrote: ↑Fri Nov 13, 2020 3:41 amHi,
Could this be a good lens for our photography work
https://www.ebay.com/itm/163710772822
This one: https://www.ebay.com/itm/Nikon-M-Plan-4 ... 0005.m1851
is a Nikon CF and can be used without eyepiece but being finite 210mm corrected it needs to be placed at 200mm of the sensor by extension (tubes or bellows)
40/0.5 seems clearly more convenient than 50/0.40 although the image still can't be very sharp on sensor
Pau
Re: 40-60 X Objective lens
What is the difference between this lens and the famous nikon 40x lens?
https://www.ebay.com/itm/Nikon-M-Plan- ... 890.l49292
https://www.ebay.com/itm/Nikon-M-Plan- ... 890.l49292
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Re: 40-60 X Objective lens
If you check http://www.krebsmicro.com/mplan.pdf you'll see that the 40x 0.65 M plan has a working distance of 1mm, which is uncomfortably short.
Re: 40-60 X Objective lens
One last objective
I try to learn new things as you give me more advises
I think this one has a good WD and A good NA, but the price is warily low...
https://www.ebay.com/itm/SPI-40-LWD-Mic ... 890.l49292
I try to learn new things as you give me more advises
I think this one has a good WD and A good NA, but the price is warily low...
https://www.ebay.com/itm/SPI-40-LWD-Mic ... 890.l49292
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- Posts: 423
- Joined: Fri Mar 01, 2013 1:43 am
- Location: Lund, Sweden
Re: 40-60 X Objective lens
Looks like a 160mm finite objective. In this era, the only ones that did not need compensating eyepieces are 1) Nikon CF and CFN objectives; and 2) some low-magnification objectives from Zeiss and Lomo (like the famous Lomo 3,7x).iHasan wrote: ↑Fri Nov 20, 2020 4:42 amOne last objective
I try to learn new things as you give me more advises
I think this one has a good WD and A good NA, but the price is warily low...
https://www.ebay.com/itm/SPI-40-LWD-Mic ... 890.l49292
So if you are looking for a 40x with longish work distance, you basically need to limit your search to a Nikon M plan/BD plan LWD or ELWD; or look for newer infinity-corrected objectives.
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Re: 40-60 X Objective lens
I have a similar looking 10x branded Edmund Optics, it too has a pastic back cap that says Japan on it. It might be alright, it's a 160mm finite objective. Never tried mine, bought it because it was $5.