Search found 53 matches

by gastrotrichman
Fri Jun 19, 2020 6:15 pm
Forum: Introduce yourself
Topic: Greetings from Regenstauf, Germany
Replies: 8
Views: 496

Re: Greetings from Regenstauf, Germany

Hi Michael,

I am an enthusiastic student of freshwater gastrotrichs. I've been working with them for about a decade. I live in the northwestern United States, and have been focused primarily on identifying local species.

Jim Kirk
by gastrotrichman
Wed May 06, 2020 3:34 am
Forum: Beginner's corner
Topic: objective nomenclature
Replies: 17
Views: 1122

Re: objective nomenclature

I understand that Leitz "locked" their DIC objectives in place. If yours are not locked in place, you will need to go through a procedure to get each objective rotated to a position where it takes maximum advantage of the DIC condenser. If they are locked in place, don't unlock them.
by gastrotrichman
Mon Apr 20, 2020 5:06 pm
Forum: Introduce yourself
Topic: Hello from Oregon
Replies: 14
Views: 6604

Re: Hello from Oregon

Hi Rorschach, I bought my Orthoplan with DIC from a fellow in England nearly a decade ago (my how time flies). The condenser is marked "Interf-Kontrast S" and "146," and has a 1.33 oel top lens. The DIC objectives also are marked "Interf-Kontrast," and were locked in place (presumably by Leitz) when...
by gastrotrichman
Fri Apr 03, 2020 3:07 am
Forum: Resources (online, books etc.)
Topic: Leitz history
Replies: 3
Views: 394

Re: Leitz history

Thanks Leitzcycler for the heads up on the book. I ordered a copy.
by gastrotrichman
Thu Apr 02, 2020 12:09 am
Forum: Resources (online, books etc.)
Topic: Leitz history
Replies: 3
Views: 394

Re: Leitz history

Thanks for sharing your knowledge. What a nice, succinct history. I love my two Orthoplans.
by gastrotrichman
Sun Mar 22, 2020 2:38 am
Forum: Beginner's corner
Topic: Camera taking bad bright field images
Replies: 22
Views: 2278

Re: Camera taking bad bright field images

If your scope has a field diaphragm, you might check to ensure it's stopped down to "match" the objective. A wide-open field diaphragm can produce "washed-out" images similar to your bright field images. If the field diaphragm is OK, I would check the condenser diaphragm to ensure it also "matches" ...
by gastrotrichman
Wed Mar 11, 2020 5:44 am
Forum: Beginner's corner
Topic: Discovery of Microorganisms + Advice on Research Microscope
Replies: 33
Views: 15014

Re: Discovery of Microorganisms + Advice on Research Microscope

"Microorganism" is a very broad term. If a light microscope is to be your primary tool, you'll probably want to consider algae, protozoans, the many, many microscopic invertebrates, and perhaps even microscopic parasites. I would avoid bacteria and viruses because their generally small size limits t...
by gastrotrichman
Sun Mar 08, 2020 2:23 pm
Forum: Introduce yourself
Topic: Greetings from Oregon
Replies: 8
Views: 4192

Re: Greetings from Oregon

Greetings back at you from another Oregonian. Enjoy the forum.
by gastrotrichman
Sun Mar 01, 2020 10:14 pm
Forum: Identification help
Topic: UFO Unidentified object!
Replies: 8
Views: 1878

Re: UFO Unidentified object!

Looks like a flatworm … planarian.
by gastrotrichman
Wed Jan 15, 2020 4:44 pm
Forum: Beginner's corner
Topic: Clean sample
Replies: 7
Views: 2223

Re: Clean sample

If you Google "make Irwin loop" you'll see information about how Irwin loops are used, and how they can be made. They allow individual critters to be captured and moved to a clean droplet of water on a slide. Using a stereoscope and a fine transfer pipette, I capture a gastrotrich (or other critter)...
by gastrotrichman
Mon Jan 13, 2020 6:43 pm
Forum: Identification help
Topic: Unknown ciliate 2.
Replies: 4
Views: 1712

Re: Unknown ciliate 2.

Sorry for the short response. Gastrotrichs tend to be in more or less continuous, fluid motion using bands of ventral cilia. Many rotifers swim, but use their anterior cilia for that purpose, and lack the longitudinal bands of locomotor cilia that gastrotrichs have. Many (but not all) gastrotrichs a...
by gastrotrichman
Sat Jan 11, 2020 3:38 pm
Forum: Identification help
Topic: Unknown ciliate 2.
Replies: 4
Views: 1712

Re: Unknown ciliate 2.

Rotifer. Definitely not a gastrotrich.
by gastrotrichman
Sat Oct 12, 2019 3:26 am
Forum: Pictures and Videos
Topic: Gastrotricha
Replies: 5
Views: 1610

Re: Gastrotricha

Nice video. The animal is in the genus Chaetonotus, which is a very large genus; spines, like those seen along the sides of this specimen, are characteristic of the genus. "Chaetonotus" is usually translated as "spiny-back" and refers to spines that are present on dorsal scales. Identification to sp...
by gastrotrichman
Sat Sep 21, 2019 3:07 pm
Forum: Off Topic
Topic: Discuss
Replies: 4
Views: 4614

Re: Discuss

In the late 1950s I used a Spencer monocular scope and an Exa SLR (the much cheaper little brother of the Exakta SLR) to make photomicrographs. The camera attached to the scope with a hinged adapter, which was rigid when the camera was "in battery" for photos. For eyeball-direct viewing, the hinge a...
by gastrotrichman
Sat Aug 24, 2019 3:38 am
Forum: Beginner's corner
Topic: My first project microscope - Optiphot questions
Replies: 11
Views: 2729

Re: My first project microscope - Optiphot questions

I didn't see a response to your question regarding removal of the filter housing. It slides up and off … should be easy.
by gastrotrichman
Sat Aug 03, 2019 12:25 am
Forum: Resources (online, books etc.)
Topic: How to study gastrotrichs
Replies: 8
Views: 4484

Re: How to study gastrotrichs

75RR Sorry, I don't know of a link. I learned the technique from a longtime gastrotrich student in New Jersey. I apologize for using the term "beads" of petroleum jelly without explanation. I was thinking of "bead" in the sense of a bead laid down by a caulking gun. Smear a little petroleum jelly in...
by gastrotrichman
Fri Aug 02, 2019 1:20 am
Forum: Resources (online, books etc.)
Topic: How to study gastrotrichs
Replies: 8
Views: 4484

Re: How to study gastrotrichs

Sauerkraut -- Yes, gastrotrichs tend to be very active and have to be slowed in order to see characters needed for identification. A 1 percent solution of magnesium chloride is often used for freshwater species, and a 7% solution for marine species. Magnesium chloride is hygroscopic and can vary fro...
by gastrotrichman
Thu Aug 01, 2019 4:23 am
Forum: Resources (online, books etc.)
Topic: How to study gastrotrichs
Replies: 8
Views: 4484

How to study gastrotrichs

A wealth of introductory information on how to study gastrotrichs was published last week. The paper deals with both marine and freshwater gastrotrichs and includes keys to families and genera. Professor M. Antonio Todaro is the senior author and is a world expert on gastrotrichs. An open access cop...
by gastrotrichman
Thu May 02, 2019 2:10 pm
Forum: Resources (online, books etc.)
Topic: Identification and general literature on fresh water protists
Replies: 4
Views: 2036

Re: Identification and general literature on fresh water protists

Hi Max, The second edition (2000) of "An Illustrated Guide to the Protozoa: Organisms Traditionally Referred to as Protozoa, or Newly Discovered Groups", edited by Lee, Leedale and Bradbury, is a fairly comprehensive guide to protozoa. It consists of two volumes, and includes lots of photographs and...
by gastrotrichman
Wed Apr 10, 2019 11:17 pm
Forum: For forum members who want to buy and sell equipment
Topic: Wild m11 lamp bulb
Replies: 3
Views: 1977

Re: Wild m11 lamp bulb

15 watt, T8 PYGMY, European base from 1000 Bulbs in Texas (their number IN-005T8514) fits the housing and lights. I think the original bulb (which I don't have) was 20 watts.
by gastrotrichman
Sun Apr 07, 2019 3:16 pm
Forum: Resources (online, books etc.)
Topic: Recommendation For Online Lab Chemicals & Supplies
Replies: 2
Views: 4048

Re: Recommendation For Online Lab Chemicals & Supplies

I've had good luck with Electron Microscopy Sciences (www.emsdiasum.com). They have a great catalog and offer way more than just electron microscopy supplies. I've also had good luck with Connecticut Valley Biological (www.connecticutvalleybiological.com/). I used to use Carolina Biological (www.car...
by gastrotrichman
Sun Apr 07, 2019 3:00 pm
Forum: Introduce yourself
Topic: Hello from Oregon
Replies: 14
Views: 6604

Re: Hello from Oregon

Hi Riku - Good luck in expanding your equipment. Is your interest in the macrozoobenthos focused on any particular group? Hi Wim - I hope you return to nematodes. I see them all the time, but basically ignore them, as I do virtually everything other than gastrotrichs … too many critters and too litt...
by gastrotrichman
Sun Apr 07, 2019 2:37 pm
Forum: For forum members who want to buy and sell equipment
Topic: Wild m11 lamp bulb
Replies: 3
Views: 1977

Re: Wild m11 lamp bulb

Thanks Michael G. I ordered a bulb that looks like it should fit. I am fixing up an M11 I've had sitting for years for a friend's wife, who is interested in tardigrades and other small things. Thanks also for the manual, which I didn't have and which she will probably like to have. I'll try to remem...
by gastrotrichman
Fri Apr 05, 2019 9:07 pm
Forum: For forum members who want to buy and sell equipment
Topic: Wild m11 lamp bulb
Replies: 3
Views: 1977

Wild m11 lamp bulb

Can anyone provide a manufacturer or part number for the lamp of a Wild M11 microscope? Threaded base, 120 volts, 20 watts. Thanks.
by gastrotrichman
Fri Mar 29, 2019 3:20 am
Forum: Miscellaneous
Topic: Question for Pipette users
Replies: 28
Views: 11691

Re: Question for Pipette users

I use and recommend Charlie's protocol, except that I use a stereo scope to make the captures from plastic Petri dishes and to set up the final slide for use with the compound scope. I heat and draw out the transfer pipette tip to increase water velocity (at least that's what I think happens) to mor...
by gastrotrichman
Sat Mar 23, 2019 6:12 pm
Forum: Introduce yourself
Topic: Greetings from Denmark and request for help (Bertrand lens)
Replies: 2
Views: 2246

Re: Greetings from Denmark and request for help (Bertrand lens)

I think the Leitz Variotube (mentioned and shown in MicroBob's first attachment) can be added to your Orthoplan between the stand and the head. The Variotube has a Bertrand lens. The Variotube Bertrand lens has the same Achilles heel as the Bertrand lens in the Pol head (shown in MicroBob's second a...
by gastrotrichman
Tue Mar 19, 2019 3:31 am
Forum: Pictures and Videos
Topic: Trying for Dark Ground photos
Replies: 4
Views: 1877

Re: Trying for Dark Ground photos

I don't have a lot of darkfield experience, but I wonder if your darkfield condenser is centered. For discussion, see: https://www.olympus-lifescience.com/en/ ... ieldsetup/
by gastrotrichman
Mon Mar 18, 2019 11:30 pm
Forum: Pictures and Videos
Topic: Cyclopoid nauplius
Replies: 10
Views: 2951

Re: Cyclopoid nauplius

Spectacular image! Thanks for the link to the key.
by gastrotrichman
Wed Mar 06, 2019 3:18 pm
Forum: Pictures and Videos
Topic: Biddulphia biddulphiana + friends
Replies: 5
Views: 1647

Re: Biddulphia biddulphiana + friends

Spectacular images!
by gastrotrichman
Fri Feb 22, 2019 3:39 pm
Forum: Introduce yourself
Topic: Hello from Portland, Oregon, USA
Replies: 7
Views: 3585

Re: Hello from Portland, Oregon, USA

Welcome Fiddlercrab. I am located in a rural area 30 miles or so south of Portland, so we share fauna, weather, moss flora, etc. I am retired with an interest in freshwater gastrotrichs. Good luck with the grandkids. Mine are still too young for a real microscope.