Will this work on my old leitz laborlux?
Will this work on my old leitz laborlux?
AmScope PA20X-B 20X Plan Achromatic Microscope Objective Lens with Black Finish...I realize it's a pos objective but it's all I can afford right now. Will this work on my 1950's Leitz Laborlux? Thanks.
Re: Will this work on my old leitz laborlux?
It has RMS thread and the difference in tube length is negligible on a 20x objective.
Leitz Periplan eye-pieces are somewhat tolerant against third party objectives. It will not be perfect but should work.
The problem could be parfocal length. I do not know how long the Amscope objective is and what type of Leitz objectives you have on your Laborlux. Are they 37 or 45 mm?
Leitz Periplan eye-pieces are somewhat tolerant against third party objectives. It will not be perfect but should work.
The problem could be parfocal length. I do not know how long the Amscope objective is and what type of Leitz objectives you have on your Laborlux. Are they 37 or 45 mm?
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apochronaut
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Re: Will this work on my old leitz laborlux?
All objectives marked as DIN are 45mm parfocal, so the Amscope objective is 45mm.
Here are several things to consider.
In case you are unsure of how to:
1) Measure your parfocal length. This is a measurement between the objective shoulder ( no thread) and the object on the stage when the objective is in focus.. Only higher powered objectives of standard working distance are very close to and only slightly shorter than the actusl parfocal length, so you can just measure an objective. A 40X dry objective will be between .3mm and 1mm shorter than the parfocal length when measured from the objective shoulder to the tip. A 100X objective just slightly longer. The parfocal length will always be greater than the objective measure but only slightly.
2) A parfocal length difference will not necessarily affect the image quality but it affects the convenience of use and raises the eventual probability of future breakage of something. Changing magnifications when objectives are 8mm different in length will eventually lead to collision(s) and even possible objective damage.
3) Inexpensive Chinese objectives are well enough engineered but in an effort to reduce their selling price they are manufactured and assembled using shortcuts in component production, assembly procedures and q.c.. This results in some objectives meeting spec. but some not. In Amscopes opinion, all units shipped ftom the Chinese factory are perfect, even though they don't test them. They leave it up to the customer to discover any defects. Here are the potential issues in comparison to what you would expect from a good Leitz 20X plan achromat objective. Poor parcentering, lower than desired contrast, lower resolution. In addition, due to the difference in tube length, a 160mm objective will magnify a bit more in a 170mm tube.
4) Leitz objectives are critically tuned to Leitz eyepieces, which provide certain optical corrections, so much so that for each Leitz objective series 37mm/170, 45mm/170 and 45mm/160 there was a different model of periplan eyepiece. Your existing Leitz eyepieces will be unlikely to provide the needed corrections for a 160mm objective from China. There will likely be chromatic aberration and loss of planarity in the image periphery that would not occur with a Leitz or other compatable objective, so buying a plan objective to achieve that level of perfiomance would be a waste of time and money.
Could you post 2 pictures of your eyepiece? I probably have that model and could test it's compatability with other mfgs. objectives for you . Picture of the top clearly showing the markings and one from the side, showing the length. The tests would at least tell you who to avoid and in general, in tests I did previously in order to assemble a portable scope with disparate 37mm parfocal objectives on it, older Leitz periplans were pretty specific.
If your objectives are 37mm, you could also search for the following as possibilities, pending compatability tests.
There was a community of smaller microscope makers in Wetzlar, all of who used 37mm parfocal at one time. Those that still exist have probably switched to 45mm parfocal but their earlier 37mm optics can still be found at good prices. Some are compatible with Leitz because they were occasionally contracted tor production.Some other German makers in other locales used 37mm too.
Seibert was a principal cooperator with Leitz, sometimes mfg. for them. Sometimes Seibert objectives are simply marked Wetzlar. 37mm (170 tube)
C.B.S. or Conrad Beck and Sons 37mm /tube?
Hacker 37mm / tube?
Hund 37mm / tube ?
Schutz 37mm / tube?
Few if any of these would be plan but planarity was always a goal of objective designers and the term not common prior to the 1960's. Some older objectives are surprisingly planar, although not designated as such. Different manufacturers had different terms that designated planarity. up until the word plan distilled as the go to word. While planar was the commonly used technical term, names such as hyperplane, periplan , complan and planoscopic are a few of the proprietary terms used to brand some manufacturer's designated planar efforts. None of these would be specifically compatible with any other but sometimes in microscope designs, unknown design compatabilities are discovered.
Other companies that used 37mm. Meopta (170mm tube), Reichert (160mm tube), PZO, older (160mm tube) M & Katera (170mm tube)
Eyepiece compatability might be o.k. or might not be. In the tests mentioned above, the 10X periplan eyepiece made for the 37mm parfocal Leitz objectives is compatible with higher power Hacker objectives and a 35X C.B.S. objective but a little off with a 10X C.B.S. objective.
Bausch & Lomb and Olympus at one time used 36.65mm, which can be shimmed to work in 37mm nosepieces. The eyepiece corrections would likely be off some but Olympus would be a potential source of a plan objective because they continued with short objectives into the era when plan was common. Bausch & Lomb had changed to longer objectives prior to the plan revolution but their 21X .50 achromat is an excellent almost plan , cheap objective. There is a water immersion version too, which occasionally shows up on ebay.
Here are several things to consider.
In case you are unsure of how to:
1) Measure your parfocal length. This is a measurement between the objective shoulder ( no thread) and the object on the stage when the objective is in focus.. Only higher powered objectives of standard working distance are very close to and only slightly shorter than the actusl parfocal length, so you can just measure an objective. A 40X dry objective will be between .3mm and 1mm shorter than the parfocal length when measured from the objective shoulder to the tip. A 100X objective just slightly longer. The parfocal length will always be greater than the objective measure but only slightly.
2) A parfocal length difference will not necessarily affect the image quality but it affects the convenience of use and raises the eventual probability of future breakage of something. Changing magnifications when objectives are 8mm different in length will eventually lead to collision(s) and even possible objective damage.
3) Inexpensive Chinese objectives are well enough engineered but in an effort to reduce their selling price they are manufactured and assembled using shortcuts in component production, assembly procedures and q.c.. This results in some objectives meeting spec. but some not. In Amscopes opinion, all units shipped ftom the Chinese factory are perfect, even though they don't test them. They leave it up to the customer to discover any defects. Here are the potential issues in comparison to what you would expect from a good Leitz 20X plan achromat objective. Poor parcentering, lower than desired contrast, lower resolution. In addition, due to the difference in tube length, a 160mm objective will magnify a bit more in a 170mm tube.
4) Leitz objectives are critically tuned to Leitz eyepieces, which provide certain optical corrections, so much so that for each Leitz objective series 37mm/170, 45mm/170 and 45mm/160 there was a different model of periplan eyepiece. Your existing Leitz eyepieces will be unlikely to provide the needed corrections for a 160mm objective from China. There will likely be chromatic aberration and loss of planarity in the image periphery that would not occur with a Leitz or other compatable objective, so buying a plan objective to achieve that level of perfiomance would be a waste of time and money.
Could you post 2 pictures of your eyepiece? I probably have that model and could test it's compatability with other mfgs. objectives for you . Picture of the top clearly showing the markings and one from the side, showing the length. The tests would at least tell you who to avoid and in general, in tests I did previously in order to assemble a portable scope with disparate 37mm parfocal objectives on it, older Leitz periplans were pretty specific.
If your objectives are 37mm, you could also search for the following as possibilities, pending compatability tests.
There was a community of smaller microscope makers in Wetzlar, all of who used 37mm parfocal at one time. Those that still exist have probably switched to 45mm parfocal but their earlier 37mm optics can still be found at good prices. Some are compatible with Leitz because they were occasionally contracted tor production.Some other German makers in other locales used 37mm too.
Seibert was a principal cooperator with Leitz, sometimes mfg. for them. Sometimes Seibert objectives are simply marked Wetzlar. 37mm (170 tube)
C.B.S. or Conrad Beck and Sons 37mm /tube?
Hacker 37mm / tube?
Hund 37mm / tube ?
Schutz 37mm / tube?
Few if any of these would be plan but planarity was always a goal of objective designers and the term not common prior to the 1960's. Some older objectives are surprisingly planar, although not designated as such. Different manufacturers had different terms that designated planarity. up until the word plan distilled as the go to word. While planar was the commonly used technical term, names such as hyperplane, periplan , complan and planoscopic are a few of the proprietary terms used to brand some manufacturer's designated planar efforts. None of these would be specifically compatible with any other but sometimes in microscope designs, unknown design compatabilities are discovered.
Other companies that used 37mm. Meopta (170mm tube), Reichert (160mm tube), PZO, older (160mm tube) M & Katera (170mm tube)
Eyepiece compatability might be o.k. or might not be. In the tests mentioned above, the 10X periplan eyepiece made for the 37mm parfocal Leitz objectives is compatible with higher power Hacker objectives and a 35X C.B.S. objective but a little off with a 10X C.B.S. objective.
Bausch & Lomb and Olympus at one time used 36.65mm, which can be shimmed to work in 37mm nosepieces. The eyepiece corrections would likely be off some but Olympus would be a potential source of a plan objective because they continued with short objectives into the era when plan was common. Bausch & Lomb had changed to longer objectives prior to the plan revolution but their 21X .50 achromat is an excellent almost plan , cheap objective. There is a water immersion version too, which occasionally shows up on ebay.