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Amoeba hunts for ciliate

Posted: Fri Nov 01, 2019 10:12 pm
by timurkhaz
Hello! Today I was lucky to see how the amoeba eats ciliate.
40x objective. I need plan apo, maybe I will steal some soon :mrgreen:


Re: Amoeba hunts for ciliate

Posted: Fri Nov 01, 2019 10:45 pm
by Hobbyst46
These are nice movies ! the first issues to improve, I would say, are contrast and illumination; did you set Kohler illumination ? if not, I would start with that. Then, if contrast is still low even after closing the condenser iris appropriately, I would consider phase contrast. For nearly transparent protists, phase contrast (or DIC if one can afford it) is a real benefit. A planachromat phase contrast or fluorite phase contrast should do the job - provide high contrast and a better depth of focus that is better than that of a Plan apochromat. Although the latter is generally an excellent objective.

Re: Amoeba hunts for ciliate

Posted: Fri Nov 01, 2019 10:57 pm
by timurkhaz
Hobbyst46 wrote:
Fri Nov 01, 2019 10:45 pm
These are nice movies ! the first issues to improve, I would say, are contrast and illumination; did you set Kohler illumination ? if not, I would start with that. Then, if contrast is still low even after closing the condenser iris appropriately, I would consider phase contrast. For nearly transparent protists, phase contrast (or DIC if one can afford it) is a real benefit. A planachromat phase contrast or fluorite phase contrast should do the job - provide high contrast and a уbetter depth of focus that is better than that of a Plan apochromat. Although the latter is generally an excellent objective.
Now I use flashlight and microscope mirror, but I have bought lamp, it will come soon. I've got condensor for dark-field, but it works not well with flashlight:)

Re: Amoeba hunts for ciliate

Posted: Fri Nov 01, 2019 11:15 pm
by Chris Dee
Looks good to me timurkhaz, well done, plenty to observe. While high performance objectives and lighting are nice to have, they are not essential IMO.
The filter effects in Shotcut (a free open source video editing program) can also be useful for enhancing footage.

Re: Amoeba hunts for ciliate

Posted: Sat Nov 02, 2019 3:31 am
by 75RR
Nice catches!

While Phase Contrast is rightly on most microscopists wish list, there are a couple of things you can try while you wait to locate a suitably priced one.

I refer to oblique. An excellent illumination technique that is effectively DIY (do it yourself) and therefore more of an art than most.

http://www.microscopy-uk.org.uk/mag/ind ... lique.html

https://www.photomacrography.net/forum/ ... hp?t=15142

viewtopic.php?f=15&t=4499#p41201

Re: Amoeba hunts for ciliate

Posted: Sat Jan 04, 2020 5:20 pm
by Radazz
Hoffman Modulation Contrast works great for protists as well. Doesn’t have the halos.

I must admit to wanting a DIC setup, but those don’t fall out of the sky.

Radazz

Re: Amoeba hunts for ciliate

Posted: Sat Jan 04, 2020 7:17 pm
by MicroBob
Hi Timur,
nice videos! You just caught the interesting moments - a Planapo wouldn't help if you had missed it.
There isn't much wrong with the video quality, maybe a bit more contrast added in video editing could improve them further.
For detail optimisation I would start with post #2 - illumination set as best as possible with your equipment?
- Condenser close to the slide, if possible focussed on the light source
- condenser aperture just a little closed ( pull eyepiece, look at objective back lens)

For the very 3D plancton life Plan objectives are not a big advantage as your objects are on different layers anyway. An Apo objective renders the out of focus areas less colourful. A high aperture Apo has the disadvantage of reduced depth of focus - so not that much to gain.

When you get your new lamp make sure to set it up in a way that the back lens of your strongest objective can bei lluminated fully.

Bob

Re: Amoeba hunts for ciliate

Posted: Sun Jan 05, 2020 11:53 pm
by mintakax
Really nice job capturing that action ! Poor ciliate seemed to be sleeping until it was too late. Life feeds on life.

Re: Amoeba hunts for ciliate

Posted: Fri Jan 24, 2020 10:46 pm
by Rossf
Nice videos-well done-good example that even “lowly” bright field can capture at least the changing outlines and cytoplasmic streaming quite well and definitely lets you see what’s going on-I find dropping the condenser low can sometimes improve contrast a bit with Brightfield-on my scope anyway-well that ciliate won’t be passing on family stories to grandkids...