Microscope test - do I need a relay lens?

[Starshade]

Hi guys,

I recently could try a Nikon Ti-E and made a few test shots with it. It has just plan fluorite objectives, but that's enough for testing.

Here's a shot with electronic flash. That's a 20x (http://objectives.nikoninstruments.com/ ... hp?c[]=114) with DIC. It uses LWD condenser, so don't expect a regular thin depth of field.



The question that I have: I noticed that the microscope camera attached to one of the port doesn't use any relay lenses. So I tried my canon 7d with the same port ( without any lenses) and managed to get a shot of this beautiful rotifer.

Still very far away from the rotifer results some other people get (especially ABEL!).

Do I understand correctly that relay lenses simply invert the image and make it easier to cover the whole sensor rather than giving any other advantages?

I am just making sure that I am getting every single bit of the current setup before I start thinking of better objectives and condensers.

[Pau]

... It has just plan fluorite objectives, but that's enough for testing.

Plan fluorites are excellent. The difference with Plan Apos is not that big. 0.45 NA isn't bad at all for a 20X but 0.75 in some new Nikon planapos is nicer.
Slide thikness and quality and your collar correction position, water deep, cleaness.... may be more relevant

Do I understand correctly that relay lenses simply invert the image and make it easier to cover the whole sensor rather than giving any other advantages?

You're right. A relay lens just changes the magnification and places the image at the adequate heigth, but not always does invert the image. All resolution is realised by the condenser/objective combination. If the image covers the whole sensor with enough good quality and is parfocal with the eyepieces you don't need a relay lens, but likely the captured image field will be bigger than the one showed by the eyepieces. This may be an advantage or disavantage depending of the subject.
With Nikon CF or CFI objectives direct projection seems a good idea.

[Starshade]

Thanks Pau,

That's quite clear. And yes, I noticed that recent plan fluorite lenses (at least by Nikon) are so much better than those produced 5 years ago... the image is definitely indistinguishable from planapo through the eyepieces. Can't say the same about Olympus - I just visited a research station filled with the latest olympus bx53 and was very disappointed by their plan fluorites (in combination with DIC and high NA condensers). The image through the eyepieces is ok, but attaching a camera show their limits right away.

So I'll keep the current configuration with the connector and focus on other elements.

[RogelioMoreno]

Starshade,

From the picture you do not need a relay lens, the way you mounted the camera is ok (I assume you were watching the specimen through the eyepieces and the camera was parfocal with the eyepieces). On what port of the Ti did you mount the camera, the front port?

That is very nice picture (a little of contrast adj., color cast remove and sharpening would help).

Rogelio

[Starshade]

Thanks Rogelio,

The microscope doesn't have a trinocular head, just one port on the right, and one port on the left side. All light was directed to the right port. The camera isn't parfocal with eyepieces.

I have a lot to learn how to edit dic pictures - especially how to remove color casts (aside from with desaturation). I don't want to increase contrast even further, otherwise the background will go darker. I think my mistake was making the polarizer at full extinction degree towards analyzer, a few degrees off would have made the background more even and brighter. I added lots of sharpness and further adjustments hurt the image in my opinion. May be I have to try other ways of sharpening.

[rjlittlefield]

I have a lot to learn how to edit dic pictures - especially how to remove color casts (aside from with desaturation).

http://www.photomacrography.net/forum/v ... hp?t=19977 discusses several approaches for dealing with a situation that seems very similar to yours.

--Rik