Who tryed Olympus CHC microscope with APS-C body ?

Starting out in microscopy? Post images and ask questions relating to the microscope and get answers from our more advanced users on the subject.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

zzffnn
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Post by zzffnn »

I agree with Ichty.

Your test slide may not be good enough. Some commercial histology slides can have cover slip-to-subject gap as deep as 0.50 mm or more (you theoretically want 0.00 mm gap).

Use an one or two micron per division stage micrometer. Or simply spread some fresh blood as thinly as possible under cover slip.

I think you meant HI 100x oil immersion objective.
Selling my Canon FD 200mm F/2.8 lens

SWIMMASTER
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Post by SWIMMASTER »

On this site, I was told to consider buying the Olympus photo eyepiece FK 2,5x. for full frame bodies.
But working with Nikon APS-C bodies, I wonder if it would not be better to buy an Olympus photo eyepiece NFK 1,67x125 ?

Ichthyophthirius
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Post by Ichthyophthirius »

Hi,

The NFK 1.67x will give you a larger crop of the image. So yes, it will work.

However,
- Your short-barrel Olympus objectives are not an ideal fit for the NFK 1.67x (LB system)
- You'd buy a $500+ projective that will give you no real advantage over your current afocal setup (you might be able to see a difference with high-end objectives but with short-barrel achromats it doesn't seem worth the expense).

Your money might be better spent on some LB objectives or on an EFSC camera. Your images look OK given the test slide; they'll just need more image processing done on them to look great.

Regards, Ichty

SWIMMASTER
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Post by SWIMMASTER »

I have the impression that the dust that is in the 50 mm prime lens shows very well in my microscopepictures. Could that be typical , because I see always the dust on my eyeballs in the oculairs ?

So, could that be a reason to buy a new lens in stead of an old one ?
The old 50 mm AI lenses are the best in sharpness but have lots of dust, the new lenses are not as sharp but no dust.
Has anybody tried to take pictures with the Nikon Macro 40 mm f2.8 ?
It should give me almost the same sharpness in the centre, and less in the corners, but using achromate microscope objectives, the corners are Always less sharp.

Pau
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Post by Pau »

I have the impression that the dust that is in the 50 mm prime lens shows very well in my microscopepictures. Could that be typical , because I see always the dust on my eyeballs in the oculairs ?
Could you post sample images? Rotating the lens without rotating the eyepiece you can find the culprit.

The main issue I find with the afocal method is dirt or defects at the eyepiece upper lens showing at the picture like blurred dark spots. You need to use very clean eyepieces. It also may apply to some extent the lens front element, I don't think that internal dust would show (I only use very clean lenses).

In principle the micro Nikon 40mm will work fine providing 1.6X magnification with a 10X eyepiece, ideal coverage for APSC. I can't recommend it without references, If eventually you buy it please keep us informed
Pau

Ichthyophthirius
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Post by Ichthyophthirius »

Hi,

When you take the camera off the lens, you can see if there is dust in the lens. The cone of light coming from the microscope eyepiece is very narrow; if there is any dust in that central area of the lens, it will show up in your pictures.

As Pau said, try to track down the location of the dust; eyepiece and sensor are other possible places.

I don't know the Nikon 40mm. Make sure that autofocus can be tured off and the aperture can be fixed wide open.

50mm is sufficient for achromat objectives and simple camera lens construction is an advantage. A very highly corrected with many lenses can be a disadvantage; it's really down to testing individual lenses, preferably at high magnification (40x, 100x), as dust shows up worst in that situation.

Canon users have an advantage here, as they have a wide range of simple M42/Nikon/Pentax/Olympus/Jena camera lenses to choose from.

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