Unexpected problems - Olympus 2,5 X NFK and 10 X Splan Apo

A forum to ask questions, post setups, and generally discuss anything having to do with photomacrography and photomicroscopy.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

Marek Mis
Posts: 2586
Joined: Sat Jul 10, 2010 9:56 am
Location: Suwalki, Poland
Contact:

Unexpected problems - Olympus 2,5 X NFK and 10 X Splan Apo

Post by Marek Mis »

A couple months ago I purchased my new FF camera Pentax K-1.
What was surprised when I took my first micrographs. On almost every image appeared light ring. See image below.

Image

I was searching the source of that light ring in various places of my BH-2.
I looked inside the trinocular head, to the condenser, lamp house ect. It was very frustracing. But yestarday I had an idea that the source of the problem (round gleam of light) can be just in my Olympus 2,5 X NFK. I made thin black paper ring and inserted it next to lower lens of the 2,5 X NFK. It works !!! Hurra !
When I was using my Pentax K-5 with its APS-C sensor the ring of light was simply outside the sensor. When I used full frame sensor the light ring appeared on the camera sensor.
But I do not understand why the light gleam has appeared. As far as I know the 2,5 X NFK was cornstructed to cooperate with 24 x 36 mm frame. What is wrong ?

The second problem concerns my Olympus 10 X Splan Apo. Some day its rear big lens simply felt out :smt017 The objective was never broken, newer felt from the table on the floor ect. What happened ?! I would not ever expect such case with so quality microscope objective. Does anybody know such case ? Now I have to look for the new objective. I tried to insert the lens to the objective but the obtained images were poor quality (not so sharp and small contrast). The objective doesn't fit for using :(

I hope my experience, at least with 2,5 X NFK, will be helpful for others who had similar problem with FF camera. Any remarks will be very appreciated.

Marek
Last edited by Marek Mis on Wed Sep 13, 2017 12:03 am, edited 1 time in total.

ChrisR
Site Admin
Posts: 8668
Joined: Sat Mar 14, 2009 3:58 am
Location: Near London, UK

Post by ChrisR »

Sorry to hear about your S-PlanApo :(

But that is interesting about the light ring
Could you post a picture of your black paper in the NFK?
Chris R

Marek Mis
Posts: 2586
Joined: Sat Jul 10, 2010 9:56 am
Location: Suwalki, Poland
Contact:

Post by Marek Mis »

Yes, I can prepare such photo :)

Marek

Alan Wood
Posts: 382
Joined: Wed Dec 29, 2010 3:09 pm
Location: Near London, U.K.
Contact:

Post by Alan Wood »

Olympus BH-2 with 10x SPlan Apo objective, 2.5x NFK photo eyepiece and full-frame Canon EOS 5D Mark II is my favourite combination. Lovely images, and definitely no light ring.

Do you see a light ring with all of your objectives?

Are you using the Photomicro Adapter L or something else?

My set-up is here:
http://www.alanwood.net/photography/oly ... scope.html

Alan Wood

Choronzon
Posts: 384
Joined: Sun Feb 21, 2010 9:14 am
Location: Chicago USA

Re: Unexpected problems - Olympus 2,5 X NFK and 10 X Splan A

Post by Choronzon »

Marek Mis wrote:
The second problem concerns my Olympus 10 X Splan Apo. Some day its rear big lens simply felt out :smt017 The objective was never broken, newer felt from the table on the floor ect. What happened ?! I would not ever expect such case with so quality microscope objective. Does anybody know such case ?

Marek
Yes, the rear lens is bonded on to the lens cell, not precision fit into a cell.
A cost cutting measure at odds with the term "quality"
I am not young enough to know everything.

Marek Mis
Posts: 2586
Joined: Sat Jul 10, 2010 9:56 am
Location: Suwalki, Poland
Contact:

Post by Marek Mis »

ChrisR wrote:Sorry to hear about your S-PlanApo :(

But that is interesting about the light ring
Could you post a picture of your black paper in the NFK?
Below there is the photo of my NFK with black paper ring.

Image

Marek Mis
Posts: 2586
Joined: Sat Jul 10, 2010 9:56 am
Location: Suwalki, Poland
Contact:

Post by Marek Mis »

Alan Wood wrote:Olympus BH-2 with 10x SPlan Apo objective, 2.5x NFK photo eyepiece and full-frame Canon EOS 5D Mark II is my favourite combination. Lovely images, and definitely no light ring.

Do you see a light ring with all of your objectives?

Are you using the Photomicro Adapter L or something else?

My set-up is here:
http://www.alanwood.net/photography/oly ... scope.html

Alan Wood
The only exception is 4 X objective. In the rest of my objectives (S plan achromats and S Plan Apochromats) the problem exists.
The width (not the diameter) of the light ring changes due to opening or closing condenser diaphragm (aperture). It is thinner and better visible (sharper) when the condenser aperture is small. The problem disappear when I insert black paper ring into the NFK.
I think that can be another reason of the light ring. Perhaps the distance of my camera to the NFK is too short and the diameter of the light ring is enough small to fit FF sensor in my K-1. Perhaps in your set this distance is much longer so your FF Canon sensor is not able to see it.
I am not sure what distance should be propper. I am enclosing image with the way of connecting my camera with to microscope with detailed description.

Image
Last edited by Marek Mis on Thu Sep 14, 2017 2:10 am, edited 1 time in total.

Marek Mis
Posts: 2586
Joined: Sat Jul 10, 2010 9:56 am
Location: Suwalki, Poland
Contact:

Re: Unexpected problems - Olympus 2,5 X NFK and 10 X Splan A

Post by Marek Mis »

Choronzon wrote:
Marek Mis wrote:
The second problem concerns my Olympus 10 X Splan Apo. Some day its rear big lens simply felt out :smt017 The objective was never broken, newer felt from the table on the floor ect. What happened ?! I would not ever expect such case with so quality microscope objective. Does anybody know such case ?

Marek
Yes, the rear lens is bonded on to the lens cell, not precision fit into a cell.
A cost cutting measure at odds with the term "quality"
Unfortunately my English is not excellent so I would like you to write the second sentence in other words ? :)

ChrisR
Site Admin
Posts: 8668
Joined: Sat Mar 14, 2009 3:58 am
Location: Near London, UK

Post by ChrisR »

ChrisR wrote:
Sorry to hear about your S-PlanApo Sad

But that is interesting about the light ring
Could you post a picture of your black paper in the NFK?


Below there is the photo of my NFK with black paper ring.
Thanks, interesting.
Chris R

Choronzon
Posts: 384
Joined: Sun Feb 21, 2010 9:14 am
Location: Chicago USA

Re: Unexpected problems - Olympus 2,5 X NFK and 10 X Splan A

Post by Choronzon »

Marek Mis wrote:
Choronzon wrote:
Marek Mis wrote:
The second problem concerns my Olympus 10 X Splan Apo. Some day its rear big lens simply felt out :smt017 The objective was never broken, newer felt from the table on the floor ect. What happened ?! I would not ever expect such case with so quality microscope objective. Does anybody know such case ?

Marek
Yes, the rear lens is bonded on to the lens cell, not precision fit into a cell.
A cost cutting measure at odds with the term "quality"
Unfortunately my English is not excellent so I would like you to write the second sentence in other words ? :)
If a microscope objective is truly a quality one, lenses don't simply fall out.
I am not young enough to know everything.

Alan Wood
Posts: 382
Joined: Wed Dec 29, 2010 3:09 pm
Location: Near London, U.K.
Contact:

Post by Alan Wood »

The Photomicro Adapter L has a baffle just above the top of the photo eyepiece. It is recessed too far for me to measure accurately, but the central hole is about 9 mm diameter.

Image

It's function could be to reduce stray light.

The distance from the sensor to the ledge on which the top section of the photo eyepiece rests should be 150.0 mm.

The figure of 125 that Olympus uses seems to be measured from the sensor to the exit pupil of the photo eyepiece.

I don't get a light ring with any objectives, and I have used from 2x to 100x.

Alan Wood

Marek Mis
Posts: 2586
Joined: Sat Jul 10, 2010 9:56 am
Location: Suwalki, Poland
Contact:

Post by Marek Mis »

Thank you Alan for your informations !

Marek

Post Reply Previous topicNext topic