Paramecium caudatum dividing --Part 2 Added

Cactusdave · Post by **Cactusdave** » Wed Jan 13, 2016 10:09 am

Charles Krebs just posted some really beautiful images of a division and conjugation in a hypotrich ciliate. This has stimulated me to upload a couple of videos of Paramecium caudatum dividing. The first shows an early stage in division with the cleavage furrow forming and clear interchange of food vacuoles and cytoplasmic contents still underway. The oral groove and oral cavity already seem to have been divided however, and oral cavities can be seen in both the daughter halves in the video. The dividing cell rotates on its axis frequently and this seems to assist formation of the furrow and separation of the two daughter cells. This video was shot on a Zeiss Standard microsope with DIC using a Zeiss X40 plapochromat objective. A Canon EOS M camera was used to take the video and it was afocally coupled through a 40mm prime lens to a Leitz Periplan 10x18 eyepiece via filter thread couplers and the eyecup threads on the eyepiece.. This combination gives rather higher magnification than could be desired for this application. The video was enhanced and edited in Serif MoviePlus X6. I have another longer clip which follows this dividing pair as the furrow deepens and blocks interchange of cytoplasmic contents. I will post it when I have refreshed my Vimeo upload allowance.

https://vimeo.com/151648861

The second clip shows a very late stage of division where the two daughter cells are held together only by a thread and finally separate, akin to the late stage on Charles's picture. This video was taken on a Nikon Diaphot with DIC and Nikon X20 and X40 Plan DIC objectives. You can see the objective swap which I have not edited out.

https://vimeo.com/151639223

carlos.uruguay · Post by **carlos.uruguay** » Wed Jan 13, 2016 7:10 pm

Both excellent!!

tsavorite · Post by **tsavorite** » Fri Jan 15, 2016 10:30 pm

There's not much privacy for a paramecium wanting to divide. (Great videos).

Protos · Post by **Protos** » Sat Jan 16, 2016 8:38 am

HI DAVE ! Nice view of this fascinating event.
I am curius to learn more about your Zeiss standard DIC setup

Cactusdave · Post by **Cactusdave** » Sun Jan 17, 2016 4:43 am

Thanks everyone.
Protos -- this is the Zeiss DIC system which uses individual sliders for each objective. I have two sliders, one nominally for the X16 Zeiss Planachromat, and one nominally for the X40 Planachromat. I have a Zeiss DIC condenser with prisms I, II and III, phase rings Ph1 and Ph2 and brightfield. For this video I used a Zeiss X40, 0.95 dry Planapochromat mounted in the X40 slider in place of the X40 Planachromat. I find this combination works well, giving DIC with both the II and III condenser prisms. The II probably works best. Good DIC effects need careful optimisation of all the centring options for the condenser itself (careful setup of illumination), and the condenser DIC prisms (same controls as for centring the phase rings) and of the rotating control knob on the slider itself. With care very good results can be obtained with this lens e.g. http://www.photomacrography.net/forum/v ... 468#182468

Protos · Post by **Protos** » Sun Jan 17, 2016 12:31 pm

Cactusdave wrote:Thanks everyone.
Protos -- this is the Zeiss DIC system which uses individual sliders for each objective. I have two sliders, one nominally for the X16 Zeiss Planachromat, and one nominally for the X40 Planachromat. I have a Zeiss DIC condenser with prisms I, II and III, phase rings Ph1 and Ph2 and brightfield. For this video I used a Zeiss X40, 0.95 dry Planapochromat mounted in the X40 slider in place of the X40 Planachromat. I find this combination works well, giving DIC with both the II and III condenser prisms. The II probably works best. Good DIC effects need careful optimisation of all the centring options for the condenser itself (careful setup of illumination), and the condenser DIC prisms (same controls as for centring the phase rings) and of the rotating control knob on the slider itself. With care very good results can be obtained with this lens e.g. http://www.photomacrography.net/forum/v ... 468#182468

Thank you Dave. I was not aware that DIC could be used on a Zeiss standard. I use DIC with my Zeiss axiophot; I own a Zeiss standard (grey) and will look for DIC parts; it should be a lot cheaper than with infinite objectives

Jacek · Post by **Jacek** » Sun Jan 17, 2016 1:31 pm

Very nice

Cactusdave · Post by **Cactusdave** » Mon Jan 18, 2016 2:07 am

Thanks Jacek.
Protos -- Zeiss 160mm TL DIC is a very complicated matter. There are at least three basic systems, and putting together a working setup is far from straightforward. I think there are several members on the site who have tried with greater or less success. Nor is it a cheap way to DIC. The components are expensive and fairly scarce, unless you are lucky. When I'm asked about the best way to acquire DIC, I always say that buying a fully functioning DIC microscope, though expensive, is the best way forward in many respects. Retrospectively acquiring parts for an existing microscope can be as expensive in the long run, frustrating and time consuming. There are some good resources on Zeiss 160mm TL DIC, here is a good place to start. http://www.photomacrography.net/forum/v ... 3548#63548

Protos · Post by **Protos** » Mon Jan 18, 2016 2:40 am

Cactusdave wrote:Thanks Jacek.
Protos -- Zeiss 160mm TL DIC is a very complicated matter. p=63548#63548

Thank you Dave, I guess I will stick to my axiophot equiped with DIC which already cost me a fortune (just wanted a complement to travel with A Zeiss standard)

Cactusdave · Post by **Cactusdave** » Mon Jan 18, 2016 3:44 am

I have the third and I think newest Zeiss 160mm DIC system referred to in Choronzon's post. The actual link to Spike Walker's FAQ page he references is http://www.the-ultraphot-shop.org.uk/faq.htm The relevant FAQ is the fourth one down. I have not experimented widely, but suspect the individual 'bespoke' combining prisms used in this system may not be as strict in their dedication to a single Zeiss objective as Zeiss might have wished to suggest.

Cactusdave · Post by **Cactusdave** » Mon Jan 25, 2016 10:03 am

This is part 2 of the video, and takes up the division process a little after where the first video left off. All the technical side is the same. In this video you can see the division furrow progressing to the stage where it is impeding movement of food vacuoles and cytoplasmic contents between two cells. It is possible to watch a prominent food vacuole with a fresh looking algal cell which is poised just at the division point. It is someway into the video before it is committed to one of the two daughter cells.
The video also shows the surface structure and rows of cilia well.

https://vimeo.com/152962800