Cell phone still and video photomicrography (Article)

[75RR]

Article review:
The only thing I noticed missing (or simply overlooked in a too-quick scan!) was any words about why the cell phone camera works so well. The fact that it does may be surprising to many people, but there's a simple explanation: the phone's camera is so small that it can be placed exactly where the human eye would be, while having a similar field of view and aperture size. As a result, any[*] optics that work well for a human eye will also work well with the cell phone. It's a marvelous bit of synergy! [/i]

http://www.microscopy-uk.org.uk/mag/art ... omicro.pdf

[gekko]

Thank you, 75RR: a very interesting article and confirms what we've seen here on the forum (e.g., rnabholz's superb images using his cell phone camera).

[IanW]

Very interesting.

I have spent a lot of time trying to get decent images from my NIkon d810 tethered to a Zeiss Standard microscope: using correct photo projection eyepiece. The quality has been dubious at best after many attempts.

I have to say - my Samsung Galaxy S6 produces better images with virtually no effort at all.

Does anyone want to buy a d810?

[75RR]

I have to say - my Samsung Galaxy S6 produces better images with virtually no effort at all.

If you are taking photos through the eyepieces with your phone then it is very likely that the problem with your NIkon d810 is due to either vibration and/or lack of parfocality of the trinocular camera tube with the binocular eyepieces.
Both these problems have simple solutions.

If vibration is the problem - isolate the camera from the microscope.

If parfocality is the problem follow these instructions:
http://www.krebsmicro.com/pdf/trinoc_a3.pdf
http://www.krebsmicro.com/parfocal/index.html

[IanW]

Good morning 75RR.

I don't know if you remember - but last year you and a few others helped me out a lot with this.

My set up is:

Zeiss Standard 18 trinouclar
Zeiss photoprojection eyepiece
Nikon F microscope tube (circa 1960) which has a relay lens inside it
Nikon d810 which I use with the mirror locked up and electronic front curtain to eliminate vibration

I am able to get half decent images with low power objectives X10 or less but with more powerful objectives images lack vibrancy, resolution etc. Shots taken with my mobile phone directly through eyepiece have far better colour, contrast and definition.

It is a mystery to me.

yes I have made sure that my scope is now parfocal. Thanks.

The only thing I can think of now is that the old Nikon microscope tube's relay lens is in someway degrading the projected image. Out of interest, what type of microscope tube do you use with your Zeiss Standard?

[75RR]

Hi IanW, thanks for the reminder.

Nikon d810 which I use with the mirror locked up and electronic front curtain to eliminate vibration

It is possible to still get vibration despite this. I have heard that some of the newer Canons have vibration problems which some of their predecessors did not have despite also having EFSC and Silent Mode. The best way to be sure is to find a way to isolate the camera from the microscope. I have my camera on a tripod which seems to work well.

Out of interest, what type of microscope tube do you use with your Zeiss Standard?

I am just using a normal eyepiece, a KPL W 12,5x/18 which I have raised 15mm in order to project a Real Image directly on to the camera sensor. There is no intermediate lens.
One can raise the eyepiece a little more or a little less - the exact amount depends on the area of the field of view you wish to capture - the important point is to raise it otherwise it projects a Virtual Image and will then need a intermediate lens.

I suppose it is possible that your relay lens could be the problem, the best way to find out is to set things up without one.
If you place the camera on a tripod, remove the relay lens and raise the eyepiece you should see an improvement.

The informal Trinocular Head I came up with was to avoid purchasing the rather expensive formal Trinocular Head, which I could not afford.
My phototube, which is from a Zeiss Photomicroscope, has no lens in it, it is basically a hollow empty tube, albeit one that can be raised and lowered in order to achieve parfocality.
The Cube, the centerpiece of my informal Trinocular, has Telen lenses as does the Optovar and therefore do not affect the tube length.
The light split is 50/50

[IanW]

Hi 75RR

Thanks very much for your detailed response.

Firstly; I am unable to really isolate microscope from camera using tripod or any other method that I can think of - limits of space etc. I suppose that vibration could be a factor - but will continue to work on the assumption that it is not (yet:-)

Secondly - the tube I am using actually has (had) a field lens (not relay as I said earlier) halfway up inside the tube. it is supposed to project the image to fill the the full old 35 mm film. I smashed this out last night as there was no way of releasing it. I took some photos again through the tube and don't notice any improvement - in fact I think that I am now getting greater enlargement / less field of view which is a bit of an annoying downside. My eyepiece is a Zeiss K MF Projektiv 3.2:1 which is supposed to almost fill a full frame dslr sensor. My trinocular tube doesn't have a facility to be raised or lowered - so back to the drawing board.

I will start up a new thread today comparing mobile phone shots with those on my dslr. Perhaps you could take a look once I start it and make your observations.
All the best

Ian

[75RR]

I smashed this out last night as there was no way of releasing it.

???
A photo and a plea for suggestions would have been a more logical step! What is the rush?
If it was difficult to remove the phototube lens then it would have been best to have assumed that vibration was the problem, and start there.
Lack of room for a tripod should not be a major problem - at least it should not be made into one.
This is a test - to see if it is vibration. You could have moved the microscope to a larger table while you conducted the test. If and when vibration is established as the culprit - better permanent solutions can be found.

My trinocular tube doesn't have a facility to be raised or lowered - so back to the drawing board.

How did you achieve parfocality if this is the case? Do you use shims?

These are made from what I believe is PVC tubing made to carry electric wiring in walls, hardware store should have something similar.
They fit perfectly into the eyepiece providing a variable height collar. Internal diameter is 23.4
I had them cut in 5mm increments (except for the first which is 2.5mm) in order to be able to raise the eyepiece to get a Real Image on the camera sensor at the correct size. You will most probably need thinner ones if you are going to use them or something similar to achieve parforcality.

My eyepiece is a Zeiss K MF Projektiv 3.2:1 which is supposed to almost fill a full frame dslr sensor.

You might want to use (as a test) one of your normal KPL eyepieces - make sure the K MF Projektiv 3.2:1 is not the problem.

This needs to be a process of elimination.
For example: if you take a photo through the Trinocular port with your Phone and the quality is less than you are getting through the eyepieces then it is safe to assume that there is a problem in the Trinocular tube.
The next step is to see if the problem is the Projection lens
or the internal tube lens (sadly no more)
or the lack of parfocality.

If the image taken through the Trinocular port with your Phone is as good as that taken through the eyepiece then vibration from the DSLR is the most likely suspect.

I will start up a new thread today comparing mobile phone shots with those on my dslr. Perhaps you could take a look once I start it and make your observations.

We know your phone camera is giving better images - but it shouldn't - so I see little point in a comparison.
Best to find the reason your DSLR is not taking better images.

[IanW]

Hi 75rr

I demolished the lens out of frustration. Last year several forum members indicated that a photo tube should have no intermediate lens and that it would degrade the image.

Reading other sites it seems I am not alone in being disatisfi6with quality of zeiss Eyepieces and Projektiv lenses for use with a dslr when projecting directly onto sensor.

I'll just put up with only being able to get 50 per cent of my view photographed. As I said - I can get a 100 per cent view through eyepiece onto my mobile phone with much clearer results and no hassle. The 32megapixels on my d810 are just wasted.

[IanW]

It now seems that I should have kept that field lens - whose purpose was to reduce the projected image to fill the full frame (35mm) and reduce vignetting.

Sadly there is so little information out there about these old Nikon F microscope to camera tubes - and the general thoughts on this forum were that no intermediate lenses should exist between eyepiece and camera sensor except with an afocal set up.

Now to see if I can source a cheap UK based Nikon F tube again...

[75RR]

The 32megapixels on my d810 are just wasted.

That is just because you have not managed to find the correct setup for that camera.

Now to see if I can source a cheap UK based Nikon F tube again..

That just will set you back where you were! Have you decided then that the problem is vibration?

It now seems that I should have kept that field lens - whose purpose was to reduce the projected image to fill the full frame (35mm) and reduce vignetting.

If that was its only function then you should still get a good image (for testing purposes), despite the size. Take a photograph with your Phone down the Phototube - see how it compares.
If the quality of the image is good find a way to isolate the camera from the microscope. Many people do. It is not the end of the world.

You might also want to try one of the binocular eyepieces in the phototube. Raise it a little. Place the camera on a tripod or similar contraption and test it to see what the image is like. (That is my setup)

I know that placing the camera on the microscope as you have done looks like a simple and ergonomic way of setting up the camera - in practical terms however - camera vibration many times makes such a setup unworkable.
If you are determined to setup a camera that way then you should consider one of the older Canon cameras.
There are plenty of discussions on the photomacrography forum as to which are most suitable for this.

[IanW]

Thanks for your continued encouragement and support 75RR.

I appreciate it and will look into isolating camera as an option. I have several eyepieces ranging from 4X, 7X up to 16X - none of which produce good images. The KPL X10 produces an acceptable image but is too 'zoomed in'. The Projektiv 3,2:1 is the best quality and produces at least 50% view of the eyepiece. I'd like to be able to get at least 75% view of the eyepiece if possible.

I will report back.

[IanW]

Hi 75RR this is a shot taken with a X40 objective. Half second exposure. It's a prepared slide of Lotus pollen - and here as a half crop, so probably about one eighth view of that seen through eyepiece.

Any comments you have about image quality will be appreciated.

[75RR]

Best not to show a crop, it is easy to stray into empty magnification.
Show the full image, just reduce the longest side to 1024 pixels.
You will have to remind me what type of illumination you have.
Did you have a blue filter in place and did you set the White Balance in the camera?
Why such a long exposure? Long exposure neutralizes camera vibration.
You might want to take two identical images. One with a long exposure and one with a short exposure.
Looking forward to your results.

[ChrisR]

Ian - I haven't heard of the D810 causing any vibration, from the "first curtain". I'm aware subsequent noise/vibration can move the subject (after the exposure) which can be a real problem.

Some of the Canons (60D in particular) do cause a vibration. Most of them make a little "tick" noise, which usually isn't a problem, though results form seasoned users, vary.

Assuming you can't get a flash to "fire inthe hole" for a test for vibration, the other solution can be to use a longer exposure, say a few seconds, so any initial movement is too short to notice. I don't have that option because the floor vibrates too much all the time, but if your phone pictures are sharp, that's not your problem.