http://confocal-microscopy-list.275.s1.nabble.com/Boosting-bright-field-resolution-with-dichroic-filters-tp7583983p7583994.html
microscopy. Haven't tried again ever since. If somebody should know a
specialist to identify the species. Like "Pleurosigma, 10 g, 50 Euro" or
reality any time soon in Germany... But whatever they use for
> Diatoms in bulk ... maybe in your (or a colleague's) kitty litter.
>
> Diatomaceous earth
>
https://en.wikipedia.org/wiki/Diatomaceous_earth>
> Diatomaceous earth consists of fossilized remains ofdiatoms
> <
https://en.wikipedia.org/wiki/Diatom>, a type of hard-shelledalgae
> <
https://en.wikipedia.org/wiki/Algae>. It is used as afiltration
> <
https://en.wikipedia.org/wiki/Filtration>aid, mild abrasive in products
> including metal polishes andtoothpaste
> <
https://en.wikipedia.org/wiki/Toothpaste>, mechanicalinsecticide
> <
https://en.wikipedia.org/wiki/Insecticide>,absorbent
> <
https://en.wikipedia.org/wiki/Absorption_%28chemistry%29>for liquids,
> matting agent for coatings, reinforcing filler in plastics and rubber,
> anti-block in plastic films, porous support for chemical catalysts,cat
> litter <
https://en.wikipedia.org/wiki/Cat_litter>, activator inblood
> clotting <
https://en.wikipedia.org/wiki/Blood_clotting>studies, a
> stabilizing component ofdynamite
> <
https://en.wikipedia.org/wiki/Dynamite>, and athermal insulator
> <
https://en.wikipedia.org/wiki/Thermal_insulation>.
>
> (I first learned of it from using kilograms in the filtration system of
> our backyard pool).
>
> Or
>
http://www.amazon.com/Diatomaceous-Earth-Food-Grade-10/dp/B00025H2PY>
>
> Diatomaceous Earth Food Grade 10 Lb
>
> <
http://www.amazon.com/Diatomaceous-Earth-Food-Grade-10/dp/B00025H2PY/ref=sr_1_1?ie=UTF8&qid=1436789646&sr=8-1&keywords=Diatomaceous+earth>
>
> byDiatomaceousEarth
> Diatomaceous earth (de) is made of tiny, fossilized diatoms (aquatic
> organisms) that accumulated over millennia in fresh water lakes. When
> mined and left untreated, this amazing product can be used in hundreds
> of different ways. However, not all diatomaceous earth is created equal.
> While most other manufacturer's hand scoop de into zip lock bags,
> diatomaceous earth brand de is professionally packaged using stainless
> steel equipment. Because of this process, you can be confident there are
> no contaminants in your food grade diatomaceous earth.
>
>
> Maybe you could repackage this from "food grade" to "microscope grade".
>
> Same order could include
>
>
http://www.amazon.com/100g-Fluorescein-Powder-Chemical-Reagent/dp/B00FJ64S3U>
>
> 100g of Fluorescein Powder, Chemical Reagent
>
> <
http://www.amazon.com/100g-Fluorescein-Powder-Chemical-Reagent/dp/B00FJ64S3U/ref=sr_1_1?ie=UTF8&qid=1436789750&sr=8-1&keywords=fluorescein>
>
> byAldon Corp
> $44.95
> <
http://www.amazon.com/100g-Fluorescein-Powder-Chemical-Reagent/dp/B00FJ64S3U/ref=sr_1_1?ie=UTF8&qid=1436789750&sr=8-1&keywords=fluorescein>+
> $6.74 shipping
>
>
>
>
> Or make transgenic diatoms (
http://www.ncbi.nlm.nih.gov/pubmed/25297896> ... centric diatoms sounds good for FFTs, and their abstract mentions
> firefly luciferase and Azami-Green GP genes), fuse their silica binding
> protein (Si-tag, see, for example,
>
http://www.ncbi.nlm.nih.gov/pubmed/21277372 ... Ecoli L2 ribosomal
> protein and its 203-273 peptide apparently are SiBP's and has been fused
> to EGFP,
http://www.ncbi.nlm.nih.gov/pubmed/22926644) to GFP, RFP,
> photoswitchable FP, iRFP, etcFP,
> and sell that/those on amazon.com
>
> enjoy,
>
> George
>
>
> On 7/13/2015 4:26 AM, Steffen Dietzel wrote:
>> *****
>> To join, leave or search the confocal microscopy listserv, go to:
>>
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy>> Post images on
http://www.imgur.com and include the link in your posting.
>> *****
>>
>> Dear all,
>>
>> two questions, first about the formula:
>>
>> I thought 0.61*lambda/(NA) (Rayleigh) would be the appropriate
>> formula for self-luminous objects (dark field, fluorescence) while for
>> bright field the fitting variant of the Abbe formula should be
>> applied: lambda/NA-obj for central illumination, lambda/2NA for NA-obj
>> = NA cond and, in general, lambda/(NA-obj + NA cond), provided that
>> NA-obj is equal or bigger than NA-cond.
>>
>> It seems though, that others are happy with 1.2*lambda/(NA-obj + NA
>> cond). Where does the 1.2 (or 2*0.6) in a bright field situation come
>> from? Would that be the paper by Hopkins and Barham (1950), that Mike
>> was referring to? Because I have no hope of understanding this paper
>> by reading through during this life (Lots of formulas my biologist's
>> brain is not flexible enough to adjust for).
>>
>> Second:
>> Is there a good source for diatoms that can be stained with
>> fluorescent dyes and self-mounted, as George suggested? I have a few
>> diatom slides for teaching (Pleurosigma), but they came already mounted.
>>
>> Steffen
>>
>>>
>>>
>>> --
>>> ------------------------------------------------------------
>>> Steffen Dietzel, PD Dr. rer. nat
>>> Ludwig-Maximilians-Universität München
>>> Walter-Brendel-Zentrum für experimentelle Medizin (WBex)
>>> Head of light microscopy
>>>
>>> Marchioninistr. 27
>>> D-81377 München
>>> Germany
>>
>
>
> --
>
>
>
> George McNamara, Ph.D.
> Single Cells Analyst
> L.J.N. Cooper Lab
> University of Texas M.D. Anderson Cancer Center
> Houston, TX 77054
> Tattletaleshttp://works.bepress.com/gmcnamara/42
>
Steffen Dietzel, PD Dr. rer. nat
Marchioninistr. 27