Bertrand lens unfocused on objectives other than 4x, is that ok?
Bertrand lens unfocused on objectives other than 4x, is that ok?
So I recently obtained a Diaphot TMD, with 4 objectives, 3 of which are phase (4x PhL, 10x Ph1, 20x Ph2). The Diaphot is great in that it has built in Bertrand lens, it is well focused on the low power 4x PhL objevctive, but totally blurred on any of the other objectives. This is what the 4x objective shows using the Bertrand lens.
Is it sufficient to only center on the low power objective?
Is it sufficient to only center on the low power objective?
Re: Bertrand lens unfocused on objectives other than 4x, is that ok?
There should be some method of focusing the Bertrand lens - not sure what it is on a TMD. You do what to center each phase ring individually.
Re: Bertrand lens unfocused on objectives other than 4x, is that ok?
There is a small knob on the turret with the Bertrand lens, but it barely moves and appears to have little or no impact on the image, it could just be broken or stuck.
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Re: Bertrand lens unfocused on objectives other than 4x, is that ok?
My TMD has a lever, not a knob.
Re: Bertrand lens unfocused on objectives other than 4x, is that ok?
Really? This is what mine has, unless I'm looking in the wrong place, but I dont see anything else on the body that could be it.
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Re: Bertrand lens unfocused on objectives other than 4x, is that ok?
This is mine. Similar to yours I guess, but with a lever attachment that is used to turn it. Mine moves smoothly throughout its range.
Re: Bertrand lens unfocused on objectives other than 4x, is that ok?
I see, mine only makes about 1/8th a turn, so I guess thats probably broken... yay!
I'm also now noticing a small clicking noise when turning it, thats probably not a good sign either.
I'm also now noticing a small clicking noise when turning it, thats probably not a good sign either.
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