MicrobeHunter.com Microscopy Forum

If part of the LED produces more blue, it can be filtered before entering the abbe? Yes possibly, eg if the projected image is larger than the bottom lens of the condenser the outer part could be 'dumped' .. I noticed the effect when projecting the image of the LED in a Jansjo desk light (so probab...

Looks like they found a ref which already has an adapted beam angle... So far, I didn't find a ref of such a LED. LED's are quite complex / can of worms This page and the next one on has some info: https://luminusdevices.zendesk.com/hc/en-us/articles/15571205799181-What-LED-Optical-Characteristics-...

I looked at the pinholes in a rather decayed sheet of generic mylar mirror-film, with a metallic objective last night and the sharpest/finest images came from using the (achro) condenser iris shut right down... I thought this was down to a 'run of the mill' 40x 0.65 Vickers objective. But this morni...

(As Hans' two photographs show) as Conrad Beck says: ..a small almost transparent body may be rendered invisible by illuminating it with a full solid cone of light from the condenser, and it may be necessary to use a small angle of light to render it visible, an imperfect image being better than non...

Is the table in here of any help? : https://archive.org/details/microscope02beckuoft/page/68/mode/2up The long and short of it seems to be that for every 0.1 of NA you resolve ~10,000 lines per inch using 'white light' (Fraunhofer Line E is actualy green) It would be nice to know how the illuminated...

I tested also different methods to filter or attenuate colors, with yellow and amber filters, wasn't satisfying or magic either. Try a "Kodak F1 Pale yellow" filter; it seems to chop off the 'stand alone' blue band pretty cleanly. I cant find a crossover (the Lee pale-yellow gelatine is not the sam...

That is very nice slow motion:-)
I would like to be able to do the same sort of thing.
Does the camera's letterbox view get taller when the frame rate is dropped ?

If you havent got any way of regulating the light (beyond an iris ) then it is quite easy to have too much light for your eye. I think that there is quite a mismatch between what is comfortable to look at with your eye and the sort of of light output you might want to take a video. It is evening whe...

There are cheap (think school demo) electrostatic charge indicators, I dug one out and the charge on a record is very definitely negative, I tried it on some glass (eyepieces and a petri dish lid) I couldnt pick up anything. It might be the damp english climate and the adjacent metal parts thats cau...

Maybe this is wrong; but I think that the antistatic guns for records try to neutralise the charge on the vinyl.
The charge on glass seems to be of the opposite polarity to PVC; So it might have exactly the wrong effect.

jackieone, you might enjoy this book:
https://archive.org/details/micrographi ... 5/mode/2up
Of course you might not

bkt, out of curiosity is your microscope halogen or LED?
I noticed that in the (old?) specifications I came across it said it was a halogen system but it could take LED 'bulbs' too, if required.

Wow ! .. A new source for stuff.
(and maybe longer lasting than cheek cells too) .

I have one of these already. I use it in the field with my Macro lens! You probably ought to have two, when you get going. As far as other kinds of lights go; if they are bright sources they might need another item to diffuse the light around the subject (much like flashguns do with macro) somethin...

Prompted by topcode's ToupeTek high speed video footage. Here is a rough idea of what the 'slow motion' option of a mobile-phone camera over the eyepiece looks like (not as fast as the topecode's camera) Unfortunately this 3 year old phone has a scratched camera glass which is why there is flaring a...

I did do rotifers a while back.

After you posted that, I had a quick go with a mobile phone (480 fps) hand held over the eyepiece and it slowed the wave down nicely.
I was using much less than 3W of light at the time and yet it still, sort of, worked
So; thanks!

A simple light that is good for the job: Dont get the the VL49 version that has the letters 'RGB' in its name.

Just plonk it on table close to the subject, it lasts a good few evenings on a charge.

(It has a diffusing front surface)

In human terms the focus distance from the end of the objective will not be so different to the focus distance when is mounted onto your microscope. (~ 2 cm with a 4x and ~5mm with a 10x) I am not sure that the lens maths will help you to easily derive the distance difference but there are a nice se...

Am I going to be in need of spacers to get the 10x objective to the correct distance to be in focus? Are you having trouble with the 10x objective, in particular ? i.e. Is the 4x objective working OK on the cone ? Using a microscope objective on a camera is a pretty 'freestyle' thing ...all sorts o...

There are quite a few objectives taken apart on this site:
https://www.funsci.it/schede-tecniche.html

(It doesn't have your objective, but it might give some general idea about how it might be put together)

Do just check (with a stereo or magnifier) that above or below the knurled ring there isn't another thread that splits the barrel. It is sometimes a bit of a guess whether an edge is just a machined ledge or the edge of a thread .. scraping into the edge with a needle can sometimes help to see what ...

I can hardly see any checker pattern, just a bit of roughness to the background.
It is great to see the flagella in slow motion!!
....Hypnotic.

I guess doing this requires quite a powerful illumination?

If you would like to explore using your mobile phone a bit further there are a couple of things to be aware of: A] Over time the eyepoint of eyepieces has got higher which can mean that the basic camera phone clamps can sit in the wrong place. B] Some mobile phones dont let the user manually set the...

As for cleaning the lens you need a good amount of dirt to really notice the difference in contrast It might be the English weather or perhaps the English glass but just about every single eyepiece from the black era microscopes I have has needed a good clean. For some reason the few eyepieces that...

I dont know if this would work for your particular microscope but see here: https://microscopyofnature.com/low-budget-condenser-darkfield-phase-contrast-and-circular-oblique-illumination Or perhaps this?: http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artjan01/...

Actually, Sacrodactyl is correct

A deep cell sounds like a good idea, but if you are after more control in terms of rotation, you could try putting them in a thin walled glass tube and then rotate that . Things like this were made 100 years or so ago. The only example pic I can find at the moment is this one: https://www.flintsauct...

'Why the flare out' .. 'why the black ring' ? My guess; the light that is entering the cone and going less than the critical angle will exit the cone and other light (heading straighter) will bounce down the inside of the cone (?) I think that the cone ought to concentrate light. Conrad Beck in 'The...

Just pop out the BF condenser and pop in the DF condenser. No It would be nice wouldn't it be? ......Tooo nice, the manufactures might say. (and if you really want the freedom to use a standardised condenser you are going to have to purchase a special mount ). Of course they each maintained other d...

The inability to get the correct height for the DF oil condenser is strange, especially given the fact that I have found no such difficulty. Would I be right in thinking that when you used the darkfield condenser on the No.5 that it came pre-mounted on a push-in disc similar to the disc with the RM...