Olympus BH-2 question

[david_b]

I have an Olympus BH-2 BHS with a flip-top condenser.
There is no swing out filter holder or slide.
How can I attach patch stops for darkfield, oblique illumination etc.?

[photomicro]

I *think* they made a 'plug-in' filter, like the one shown in the pictures. I have no idea what make this is.


This is a blue filter, but can support other discs such as stops.

Of course whether this is the ideal place for such a stop depends on the design of the condenser.

Another forum member also 3-D prints a device that fits these condensers, and is raised further up into the condenser body, so bringing stops nearer the iris.

I am sure he will join the discussion at some point.

DSC06422.jpg (53.89 KiB) Viewed 4421 times

DSC06421.jpg (83.46 KiB) Viewed 4421 times

[dtsh]

Something like thus?: http://earth2geologists.net/Microscopes ... bstage.jpg

Found from http://earth2geologists.net/Microscopes ... Scopes.htm

Unless I am missing something, that looks to be the easiest solution. If you have access to a 3D printer, something like that could be whipped up pretty quick.

Edit: If you're brave, you could drill and tap the mount and secure a filter holder directly underneath the condenser to pivot on a bolt threaded into the hole.

[Saul]

...Another forum member also 3-D prints a device that fits these condensers, and is raised further up into the condenser body, so bringing stops nearer the iris. I am sure he will join the discussion at some point....

David asked me this question through another channel ...
Initially I answered, no, nothing will keep insert inside because of the conical shape. Even simplified insert (no magnets, flat base) will not help - condenser base is hanging in the air...
But...morning is smarter than evening - I have very thin big size steel washers (bought for the initial testing), if they are right size, they can be glued (double tape) to the base of the condenser, and my type insert (has to be designed for this condenser) can be attached to this condenser. If it sounds logical, I need some exact dimensions in mm, at least one number after coma (attached) and distance between bases of the cone (not along the side wall but perpendicular):

[david_b]

Something like thus?: http://earth2geologists.net/Microscopes ... bstage.jpg

Found from http://earth2geologists.net/Microscopes ... Scopes.htm

Unless I am missing something, that looks to be the easiest solution. If you have access to a 3D printer, something like that could be whipped up pretty quick.

Edit: If you're brave, you could drill and tap the mount and secure a filter holder directly underneath the condenser to pivot on a bolt threaded into the hole.

Good information, thank you.

[PeteM]

Three other options:

1) Recollection is that the dovetail base of the condenser comes off with a few screws. Can't recall if extra care is required to keep the iris leaves in place as it's removed - replacing those requires a bit of patience. Anyhow once off, the inside can easily be machined, parts can be epoxied on, etc. For example, I've modified some Olympus condesers to fit and try DIC prisms up inside as close to the iris plane as possible.

2) Another possibility for darkfield is to be on the lookout for a proper darkfield or olique condenser and fit it to the BH2. A Loma oblique, for example, ended up OK on a BH2.

3) You can also support something from the base of the BH2, perhaps made of camera extensions and adapters to get just below the condenser height.

[david_b]

David asked me this question through another channel ...
Initially I answered, no, nothing will keep insert inside because of the conical shape. Even simplified insert (no magnets, flat base) will not help - condenser base is hanging in the air...
But...morning is smarter than evening - I have very thin big size steel washers (bought for the initial testing), if they are right size, they can be glued (double tape) to the base of the condenser, and my type insert (has to be designed for this condenser) can be attached to this condenser. If it sounds logical, I need some exact dimensions in mm, at least one number after coma (attached) and distance between bases of the cone (not along the side wall but perpendicular):

Thanks I'll measure up and send you a PM.

[david_b]

Three other options:

1) Recollection is that the dovetail base of the condenser comes off with a few screws. Can't recall if extra care is required to keep the iris leaves in place as it's removed - replacing those requires a bit of patience. Anyhow once off, the inside can easily be machined, parts can be epoxied on, etc. For example, I've modified some Olympus condesers to fit and try DIC prisms up inside as close to the iris plane as possible.

2) Another possibility for darkfield is to be on the lookout for a proper darkfield or olique condenser and fit it to the BH2. A Loma oblique, for example, ended up OK on a BH2.

3) You can also support something from the base of the BH2, perhaps made of camera extensions and adapters to get just below the condenser height.

Thank you, 3) sounds like the easiest option.

Alternatively, it looks like this type of BH-2 condenser could be adapted and is relatively inexpensive. Is it any good?

[PeteM]

The Olympus 1.25 na condenser isn't bad. But your .90 na Achro condenser is better color corrected and better able (with the top lens flipped out) to fully cover the field of a 4x objective.

[carlh6902]

For the BH2:

https://drive.google.com/file/d/14VRljG ... sp=sharing

https://drive.google.com/file/d/1mq5xgw ... sp=sharing

Carl