BD Objective Survey / Options

[ray_parkhurst]

Maybe not ideal but there are 32mm ID fiber optic ring lights that slip onto the outside of an m plan apo. I have one but haven't really tried it out yet.

I've had good luck with a couple types of small diameter LED ringlights on various objectives, mostly for coins but some have been very close to optimum for the contact surface imaging. In particular I've been successful using the 20x MM objective with two types of COB LED ringlights, both taken from LED headlights. The result has been similar to what I showed above, showing good contrast between the contact surface and surrounding surfaces with nice bright delineation ring. I have not attempted to use ringlights with the standard Mittys yet, but perhaps that would be worth a try. Problem is I only have a 5x and 10x, no 20x or 50x, so limited usefulness for the contact imaging. I have been considering getting a 20x but now I know a 50x BD might work well so I'll be looking for one of those.

[Saul]

Maybe not ideal but there are 32mm ID fiber optic ring lights that slip onto the outside of an m plan apo. I have one but haven't really tried it out yet.

I've had good luck with a couple types of small diameter LED ringlights on various objectives, mostly for coins but some have been very close to optimum for the contact surface imaging. In particular I've been successful using the 20x MM objective with two types of COB LED ringlights, both taken from LED headlights. The result has been similar to what I showed above, showing good contrast between the contact surface and surrounding surfaces with nice bright delineation ring. I have not attempted to use ringlights with the standard Mittys yet, but perhaps that would be worth a try. Problem is I only have a 5x and 10x, no 20x or 50x, so limited usefulness for the contact imaging. I have been considering getting a 20x but now I know a 50x BD might work well so I'll be looking for one of those.

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[ray_parkhurst]

viewtopic.php?p=235463#p235463

Thanks Saul, looks a lot like what I've done for my BD Illuminator. but I don't see where the light exits the illuminator. I see what looks like aluminum foil covering the exit aperture, but is this just a reflection from somewhere inside the illuminator? Please explain. I guess the two ringlights give different lighting cone angles?

[RobertOToole]

Hi Ray,

Hope this helps even though I'm a couple months behind!

I know there are Mitty BD Plan objectives with presumably same optics as their MPlan Apos. Can anyone comment on these? What mount do they use? They look quite large. If anyone has a 5x, 10x, or 20x, I'd love to know their lighting angles. For my stylus imaging I need an angle of ~45-deg for best results. For coins I'm looking for higher angles.

The Mitutoyo BDs are the same lens internally as the M Plans.

The outer lens cover unscrews, I'm surprised no one in the thread mentioned this.

From my site, this is the 10x, not very pretty without the shiny cover

This should help with the light angle.

Takes a few minutes to make a disk out of flocking paper to block the BD light path.

Best,

Robert

[Scarodactyl]

I think that might defeat the purpose a bit for darkfield imaging, though it's ideal for anything else. Is the tip narrower than the non bd equivalent when the shell is off?
I got a halogen ring light that fits over the end of my mitties (but doesn't slide all the way on because of a lip), and they must have been meant for long working distance industrial zoom lenses, as the light doesn't touch the specimen at all even with the 5x. Thinking of 3d printing a reflector to paint silver to adjust that angle.
Another interesting option are adjustable-angle 8 point ring lights made by chiu and aold by a few brands. I have two, they're a bit big for a mitty but might still work? My goal for them is transmitted rather than epi darkfield.

[RobertOToole]

Is the tip narrower than the non bd equivalent when the shell is off?

Yes, the cover-less BD barrel is narrower and the front element is less set-back from the edge then the regular M-Plan. Don't remember the exact differences off the top of my head. I sold my set of BD plans or I would volunteer to measure it for you. (Later I also sold my set of M Plans and started over buying M Plans new due to inconsistent IQ issues buying used Mitutoyos but thats another story)

Best,

Robert