Problem with Diaplan

[samloi]

Hi, I recently bought a Diaplan on ebay, shipped from the UK to Bangkok. It appears in reasonable condition with everything turning and moving smoothly, but I can't get an image. The objectives are Pl Apo 25, 40, and 100, 170/0.17. Although the scope was made for 160, the manual says 170 will work above 16X. I tested the eye pieces (complete head) on my Diavert, and they work normally. The condensor is a UKO universal (513594) with a 0.90 S 1.1 top. Everything looks normal on the condensor. I have tried every combination of aperture, field diaphragm, in conjunction with raising and lowering the condensor while trying to focus, that I can think of, but without any luck. I tried one of the objectives on the Diavert, and it produced and image, but very dark. I also tried several objectives from the Diavert, and nothing. At this point, I have run out of ideas. Can anyone shed some light on this problem?

[Hobbyst46]

Perhaps the stage or condenser are locked for transport or are limited in positioning?
http://www.microscopy-uk.org.uk/mag/ind ... aplan.html

[apochronaut]

The condenser shouldn't affect whether you can focus an image or not, just the quality or lack of light. I presume you are getting light to the stage.
I would first check Hobbyist46's thought and if not look for a intermediate problem between the nosepiece and head.

[samloi]

Yes, the light is very good. The condensor also moves up and down smoothly and freely, as do all the other components

[75RR]

Have a look at the nosepiece - it may be out of position.

[Hobbyst46]

Sometimes the slide is upside down... happened to me

[einman]

As 75RR indicated the nose turret slides in and out. Make sure it is seated in properly and aligned. A photo of the scope may help. Is there a slider mounted to the left of the nose turret? If so it may not be seated properly etc. There were a few options for sliders available. Simple way would be to remove it if you have one, then check.
I have purchased and set up 3 Diaplans and generally any focusing issues are the result of overlooking a simple adjustment.

[MJB]

Hi,

I would appreciate it if you would clarify what you mean by not being able to produce an image. Is the view completely dark or is light coming through but you are not able to focus properly?

If the latter, and there is no obstruction in the condenser, try to determine if the stage travels through its entire range up and down. If not, then follow-up on the suggestion made by Hobbyst46. If that does not solve the problem, you may also want to check the rack gear. Several years ago I had to have a replacement rack gear manufactured for a Diaplan I owned which was shipped with the stage mounted and no blocking under or on top of the stage. The rack gears in the Diaplans, Metalloplan 2, Orthoplan 2 and Aristoplans are quite brittle and surprisingly easy to damage. In my case the stage was in its uppermost position and a few of the top teeth were sheared off which prevented the stage from travelling its entire range. Unfortunately, this turned out to be a not an uncommon problem with the Diaplans of that era and I quickly sold all of the remaining gears I had ordered to others who had similar experiences (and a few people who simply wanted spares).

Mike

[einman]

Yes I recall reading about your experience MJB. I have 2 extra racks for that reason..