Hi Oliver, thank you for your amazing videos. I have learned so much from you and in fact you also helped me to decide for a 30+ year old (Olympus) microscope instead of a new one from the shelf for I have always been one of these guys who like to deep dive into the technical aspects and fiddle around with components in addition to the primary observing aspect. So one thing came to the other: trino head, additional objectives and finally phase contrast which from my pov was a really good decision to buy as it was quite cheap (200 Euros for condenser, two objectives and centering telescope). I am really amazed even to rediscover simple objects like cheek or blood cells with this technique without the requirement of staining. Just my 2 cents on this topic.
Good discussion Oliver. I have 2 old Zeiss microscopes with phase contrast condenser and 3 PC objectives. In the past, I used the PC microscopes for asbestos work. That said, they are great for biological work, particular for live specimens. It makes no difference for stained specimens and PC objectives are fine for bright field and general work. The disadvantage of a "halo" effect is not a big deal on my microscope compared to the benefits for viewing otherwise transparent organisms and the organelles within them. I have a feeling that the serious enthusiast will consider the money to be well spent once they see the image contrast, particularly compared to bright field at 400x and above. Just my opinion
I got a phase contrast microscope and i found it very useful though as you say bright field is enough for 99% of the time, it also works in bright field mode though the image quality isn't as good as with a normal bright field objective its still 100% usable and if i put the 100X condenser mask with the 10X objective it works as dark field too. I hope im not annoying you with all my messages, this is the last one I promise.
Which AmScope would you suggest? I want darkfield, phasecontrast and around 1.5k-1.6k magnifier with a good camera (trino). Can't find the right microscope
Maybe other interesting questions about Phase contrast microscopes: - Can any microscope be upgraded to a Phase contrast microscope? - if not, what do I need to look for when buying a micrscope if I consider later upgrading to PC? - What are examples of good affordable (entry level) microscopes that can later be upgraded to PC?
Upgradability: You need to fit a phase contrast condenser and you need phase contrast objectives. With the 160mm standard, the objectives will be solved, but you might not be able to fit phase contrast condensers under the microscope. Generally I would say that it does not pay off to convert entry level microscopes to PC. The cost of the objectives and condenser can by far outdo the initial cost of the microscope, so it might simply be better to shop for a new microscope when the time comes. PC sets are also not so easily available for low cost microscopes. I think Amscope offers some PC upgrade sets for some microscopes, but one would have to check if this also fits others. One possibility is to decide on a system, eg Olympus CH/BH and then buy parts for that second hand.
"Phase contrast ... introduces optical artifacts." ... "This bright ring really doesn't exist." There is so much wrong with theses statements that I really don't know where to begin. First of all, an artifact is something that is produced BY THE INSTRUMENT INDEPENDENT OF THE SPECIMEN. Chromatic aberrations, spherical aberrations, detector floaters, etc. are artifacts - phase contrast birefringence is, in no way, an "optical artifact" that "doesn't exist" in the specimen. What phase contrast is doing is using instrumentation to make subtle gradients of the specimen's refractive index visible to the observer. In fact, it is the exact opposite of an "optical artifact". This is really important. All that any microscope does is use intrumentation to make that which is normally invisible to an observer visible. You might as well say that the Paramecium's cillia "don't really exist" because we cannot see them with our naked eyes. All of the many microscopic methods that you have so elegantly demonstrated - bright field, dark field, polarization, Rheinberg illumination, and phase contrast, are just different techniques to make different aspects of the specimen more visible. Frankly, as a microscopist who has yearned for a differential interference contrast scope for several years now, I think that phase contrast is a wonderful technique for anyone who longs to observe live specimens in their greatest detail. It's far more accessible than DIC.
Can not say, because it depends on the specific research. DIC is quite expensive. For simple cell counting (eg for determining cell count of yeast for fermentation) you do not even need Phase or DIC. For seeing bacteria, Phase is sufficient.
Can you use phase contrast objective lenses with a regular iris condenser to see regular brightfield or does that not work? Would I have to switch my whole objectives set out for bright feild objectives in order to see brightfield or does the condenser determine whether your seeing brightfield by itself?
@@oneworldonepeople28 Works best for thin specimens like bacteria. Thick and larger specimens (lower magnification needed) are not so good. Best for 10x, 40x, 100x oil. I recommend 40x (as no oil needed).
At 40x objective it don't really work because if a bit larger it turns really dark. Then bit change of the diameter of the stop, it turns into a bright field. do I need stronger light?
Phase Contrast converts differences in refractive index to brightness. DIC also uses differences in refractive index but the image produces looks 3D (due to presence of "shadows" that are created).
Very good oliver! Their are no words for your channel. We will welcome all your videos. Keep it up.
Hi Oliver, thank you for your amazing videos. I have learned so much from you and in fact you also helped me to decide for a 30+ year old (Olympus) microscope instead of a new one from the shelf for I have always been one of these guys who like to deep dive into the technical aspects and fiddle around with components in addition to the primary observing aspect. So one thing came to the other: trino head, additional objectives and finally phase contrast which from my pov was a really good decision to buy as it was quite cheap (200 Euros for condenser, two objectives and centering telescope). I am really amazed even to rediscover simple objects like cheek or blood cells with this technique without the requirement of staining. Just my 2 cents on this topic.
FINALLY, AN ANSWER!
`Thank you for helping make up mind objectively!
You explained it very well, very useful information, thank you very much.
Just modded my microscope for darkfield microscopy. One of the best sources of info on phase contrast!
Good discussion Oliver. I have 2 old Zeiss microscopes with phase contrast condenser and 3 PC objectives. In the past, I used the PC microscopes for asbestos work. That said, they are great for biological work, particular for live specimens. It makes no difference for stained specimens and PC objectives are fine for bright field and general work.
The disadvantage of a "halo" effect is not a big deal on my microscope compared to the benefits for viewing otherwise transparent organisms and the organelles within them.
I have a feeling that the serious enthusiast will consider the money to be well spent once they see the image contrast, particularly compared to bright field at 400x and above.
Just my opinion
Thank you a lot for the explanation and opinion!
good darkfield condensor and good objectiv works better than PH-optics
I got a phase contrast microscope and i found it very useful though as you say bright field is enough for 99% of the time, it also works in bright field mode though the image quality isn't as good as with a normal bright field objective its still 100% usable and if i put the 100X condenser mask with the 10X objective it works as dark field too. I hope im not annoying you with all my messages, this is the last one I promise.
If you have a dark field of view, you can do phase contrast with a used PH lens. It's only 15 - 25 dollars and a little work of course.
Which AmScope would you suggest? I want darkfield, phasecontrast and around 1.5k-1.6k magnifier with a good camera (trino). Can't find the right microscope
I have phase. But no telescope to centre the rings. £100 for one!I worked out you can centre by taking eyepiece out and looking down the tube.
You need a piece of plumbing pipe and two eyepieces with different magnifications.
To be clear, can Phase contrast be used without the condenser? Only the Pl objective?
Maybe other interesting questions about Phase contrast microscopes:
- Can any microscope be upgraded to a Phase contrast microscope?
- if not, what do I need to look for when buying a micrscope if I consider later upgrading to PC?
- What are examples of good affordable (entry level) microscopes that can later be upgraded to PC?
Upgradability: You need to fit a phase contrast condenser and you need phase contrast objectives. With the 160mm standard, the objectives will be solved, but you might not be able to fit phase contrast condensers under the microscope. Generally I would say that it does not pay off to convert entry level microscopes to PC. The cost of the objectives and condenser can by far outdo the initial cost of the microscope, so it might simply be better to shop for a new microscope when the time comes. PC sets are also not so easily available for low cost microscopes. I think Amscope offers some PC upgrade sets for some microscopes, but one would have to check if this also fits others. One possibility is to decide on a system, eg Olympus CH/BH and then buy parts for that second hand.
Thanks
Sir i have a serious question, so i am going to buy a binocular micrlscope but its brand is wally sky and i dont know if its good or not.
Thank you
what is the approximate
cost of phase contrast microscope - olympus with camera
"Phase contrast ... introduces optical artifacts." ... "This bright ring really doesn't exist."
There is so much wrong with theses statements that I really don't know where to begin.
First of all, an artifact is something that is produced BY THE INSTRUMENT INDEPENDENT OF THE SPECIMEN.
Chromatic aberrations, spherical aberrations, detector floaters, etc. are artifacts - phase contrast birefringence is, in no way, an "optical artifact" that "doesn't exist" in the specimen.
What phase contrast is doing is using instrumentation to make subtle gradients of the specimen's refractive index visible to the observer.
In fact, it is the exact opposite of an "optical artifact".
This is really important.
All that any microscope does is use intrumentation to make that which is normally invisible to an observer visible.
You might as well say that the Paramecium's cillia "don't really exist" because we cannot see them with our naked eyes.
All of the many microscopic methods that you have so elegantly demonstrated - bright field, dark field, polarization, Rheinberg illumination, and phase contrast, are just different techniques to make different aspects of the specimen more visible. Frankly, as a microscopist who has yearned for a differential interference contrast scope for several years now, I think that phase contrast is a wonderful technique for anyone who longs to observe live specimens in their greatest detail. It's far more accessible than DIC.
I'm studying biotechnology, so i think i'm going to need a phase or a DIC. Which one do you think is the best choice for biotechnology?
Can not say, because it depends on the specific research. DIC is quite expensive. For simple cell counting (eg for determining cell count of yeast for fermentation) you do not even need Phase or DIC. For seeing bacteria, Phase is sufficient.
Can you use phase contrast objective lenses with a regular iris condenser to see regular brightfield or does that not work? Would I have to switch my whole objectives set out for bright feild objectives in order to see brightfield or does the condenser determine whether your seeing brightfield by itself?
Phase objectives work in brightfield as well. Condenser determines it.
@@MicrobehunterMicroscopy is there a loss of quality if phase contrast objective us used in brightfield mode compared to normal objective?
@@oneworldonepeople28 Yes a small loss in quality. Watch this video where I talk exactly about this topic: ruclips.net/video/SKZNN4N4rI0/видео.html
@@MicrobehunterMicroscopy thank you! Is phase contrast good for all magnification levels or only for higher?
@@oneworldonepeople28 Works best for thin specimens like bacteria. Thick and larger specimens (lower magnification needed) are not so good. Best for 10x, 40x, 100x oil. I recommend 40x (as no oil needed).
Do I need different sizes of darkfield patch stop if my condenser is fixed? It doesn't have a condenser knob.
Generally one should work for several objectives. THe patch stop must be larger for larger magnifications, but often one will work for several.
At 40x objective it don't really work because if a bit larger it turns really dark. Then bit change of the diameter of the
stop, it turns into a bright field.
do I need stronger light?
Maybe because the aperture of my condenser, it's about n.a. 0.65
What is the difference btw phase contrast and DIC?
Phase Contrast converts differences in refractive index to brightness. DIC also uses differences in refractive index but the image produces looks 3D (due to presence of "shadows" that are created).
Can you take a review of simple microscope instead of compound microscopes?
Simple microscopes are magnification lenses. Do you mean stereo microscopes?
@@MicrobehunterMicroscopy I mean light microscopes which is the body tube is moving rather than the stage.
Ok, stereo microscopes in this case. Will do a review.
Luckily You look like my cousin...like😀