Pond water - Beginner afocal video
Pond water - Beginner afocal video
Hi,
I had the chance to observe a few drops of pond water. I made a video with my entry-level monocular scope and an iPhone 5s in afocal technique. I found a very funny bunny-like worm? that I couldn't identify. It was very long and seemed to have feet only at the upper and lower part of its body. I also found many rotifers (a big colony of them), and spent a lot of time observing diatoms at high power.
I had some format issues when gluing the videos, and lost some resolution. But here it goes anyway:
https://www.youtube.com/watch?v=HnWU0sg ... e=youtu.be
And here is the funny one on original resolution (what is it?)
https://www.youtube.com/watch?v=ZKbT4VQctbI
I know the equipment is quite basic, but I think there is a lot of room for improvement. I would really appreciate your advice.
Thanks in advance for watching it!
I had the chance to observe a few drops of pond water. I made a video with my entry-level monocular scope and an iPhone 5s in afocal technique. I found a very funny bunny-like worm? that I couldn't identify. It was very long and seemed to have feet only at the upper and lower part of its body. I also found many rotifers (a big colony of them), and spent a lot of time observing diatoms at high power.
I had some format issues when gluing the videos, and lost some resolution. But here it goes anyway:
https://www.youtube.com/watch?v=HnWU0sg ... e=youtu.be
And here is the funny one on original resolution (what is it?)
https://www.youtube.com/watch?v=ZKbT4VQctbI
I know the equipment is quite basic, but I think there is a lot of room for improvement. I would really appreciate your advice.
Thanks in advance for watching it!
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Re: Pond water - Beginner afocal video
Some really good shots of the Rotifers!
AO Series 4 Bright/Dark Phase
AO 120 Darkfield
Zeiss Photomicroscope (being built slowly)
AO 120 Darkfield
Zeiss Photomicroscope (being built slowly)
Re: Pond water - Beginner afocal video
Thank you!
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Re: Pond water - Beginner afocal video
What does afocal mean?
Re: Pond water - Beginner afocal video
In the afocal technique, you capture the exit pupil of an eyepiece with a lens mounted device. In other words, the most common practice of afocal photography, in astronomy or microscopy, consists of placing your phone in front of the eyepiece, hopefully with an adapter to get a still image. It's quite a rough, beginner, low budget technique.
On the other hand, when you have a DSRL or a dedicated camera, you can place the sensor at the focal plane to capture the image formed by the objective. This is called prime focus photography, and this is how things should be done to get decent images.
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Re: Pond water - Beginner afocal video
Nice clean videos.
I'll never understand the thumbs down responses on youtube. Your videos are sharp and clear and you captured some nice little pieces of footage. I guess there's a critic in every crowd. Probably some bumb who's never done anything more than click on a youtube video.
I'll never understand the thumbs down responses on youtube. Your videos are sharp and clear and you captured some nice little pieces of footage. I guess there's a critic in every crowd. Probably some bumb who's never done anything more than click on a youtube video.
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Re: Pond water - Beginner afocal video
Thanks. Someone did explain that once.Javier wrote: ↑Mon Oct 19, 2020 12:33 amIn the afocal technique, you capture the exit pupil of an eyepiece with a lens mounted device. In other words, the most common practice of afocal photography, in astronomy or microscopy, consists of placing your phone in front of the eyepiece, hopefully with an adapter to get a still image. It's quite a rough, beginner, low budget technique.
On the other hand, when you have a DSRL or a dedicated camera, you can place the sensor at the focal plane to capture the image formed by the objective. This is called prime focus photography, and this is how things should be done to get decent images.
Re: Pond water - Beginner afocal video
Re: Pond water - Beginner afocal video
Hi,hans wrote: ↑Mon Oct 19, 2020 4:41 amOften not the case with microscopes:
http://krebsmicro.com/photomic1/photomic1.html
I read the article. Please help me understand some points of it.
From your quotes I understand that you are arguing that placing a fixed lens camera isn't rough because there is some sort eyepiece compensation that helps with off-axis aberrations? In my experience, the fixed lens camera will introduce its own aberrations and artifacts and it's never a great idea to add more (in some cases much more) elements between the sensor and the focal plane plane image.
Thanks for the article, it was an interesting reading.
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Re: Pond water - Beginner afocal video
It's kind of hardware specific Javier. In some old microscopes and with certain lenses the objective and eyepiece combine to single optical system. In some cases, the contribution of the eyepiece can be significant and noticeable.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination
Re: Pond water - Beginner afocal video
Interesting, that make sense with older models. I don't totally get if there is a place for afocal high resolution modern micro photography nowadays. That would be something new to me in terms of optics.BramHuntingNematodes wrote: ↑Mon Oct 19, 2020 4:07 pmIt's kind of hardware specific Javier. In some old microscopes and with certain lenses the objective and eyepiece combine to single optical system. In some cases, the contribution of the eyepiece can be significant and noticeable.
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Re: Pond water - Beginner afocal video
Someone else would have to chime in there-- my newest compound microscope is from the late 60s.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination
Re: Pond water - Beginner afocal video
In good quality finite microscopes, one should think of the objective and the eyepieces as a complete lens system. The eyepieces are generally tasked with correcting the chromatic aberrations.
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)
Olympus E-P2 (Micro Four Thirds Camera)
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Re: Pond water - Beginner afocal video
I can't access the videos. They are designated as private.
Re: Pond water - Beginner afocal video
Fixed!DonSchaeffer wrote: ↑Thu Oct 22, 2020 7:42 amI can't access the videos. They are designated as private.