You will have to do sample preparation, grinding down to lest say 2000 grit and polishing down to 1 micron and have a very flat surface. Also normally you will have to etch the surface to see the microstructure.
Well damn. I just picked up a huge metallurgical microscope in a junk shop for £20. Probably from the 1970s. It was sold as not working but it only needed cleaning, tuning up and a new bulb. The objectives are perfect
When we image fluorescent samples, we shine (very bright) light down the light path through the objective onto the specimen, with bounced light coming back through the filters to show only the labelled parts of the specimen. As far as I'm aware, this doesn't require any special design of the objective itself, but you seemed to be implying that objectives for metallurgical microscopes need to be built with a separate light path for the incoming light. Is there a reason for that difference? Is it because you need the incoming light to be at an angle to get useful illumination, or does the incoming light cause noise? E.g., in fluorescent microscope, you filter out all of the excitation light, so you might not see any reflection artefacts caused by the light going down the lens
I recently scored an older Vickers Instruments microscope from an auction for equipment taken from a machine shop. It's designed to be used for both transmitted and incident light microscopy. I agree with your take on the question that a stereo microscope should have sufficient resolution for knife sharpening. I think higher resolution is useful for measuring surface roughness for highly polished surfaces, but I doubt a knife edge is the right application. As an electronics engineer I am looking forward to examining semiconductor devices which have structures in the micrometers.
Hi all Metallurgical microscope would be nice to have for knife sharpener, however they are built with bit different approach. You need to prepare sample (often with resin), grind it, eatch it and then view it under microscope. With knife sharpening you do not have this luxury to prepare sample, so the best what you can do is with digital single tube microscope or stereo microscope, both build on the same concept. For this you need good incident lighting with Ra/CRI at about 90 or higher, because you’ll get nasty blue/yellow smears on the image from reflections. Last but not least, forget to observing the apex of the grind. With good quality grind the apex go below 0.3 um, which is above what light microscopes can deliver, irrelevant of their construction. With light microscope you can see the grind but not the apex. For apex inspection you need minimum laser microscope or even electron microscope. With both of them you need again system to position knife correctly and with electron microscope, big enough tube to fit the whole knife. It is extremely difficult and pricy to find electron microscope that can fit 30 cm sample, and I believe making a sample from your knife is not your choice. Overall stick with stereo microscope or high mag digital. Buy yourself good and small incident lights, and think about how to position the grind to objective so it can be perpendicular. I am in a process as well, but sharing my findings. Hopefully someone will read it and consider. @Olivier great channel I’ve learn a lot from your lectures.
You would also have, all else being equal, higher spherical aberration if viewing a conventionally-prepared slide on a metallurgical microscope. This is because the metallurgical objectives do not compensate for the cover glass.
Would it be possible to mimic a metallurgical microscope with a trinocular microscope by shining a collimated light beam through the camera tube? Because the top-illumination in a metallurgical microscope is done by means of a beam-splitter anyway. I myself only have an antique single-tube compound microscope with a mirror so I can't check it out. But I remember that Ben Krasnow from the applied science channel drilled a hole in a cheap microscope and inserted a simple beam splitter to turn it into a metallurgical microscope. We bought a relatively cheap ($1300 at 50% off) metallurgical microscope from amscope at work. (but ofcourse UPS delivered it to the wrong address and then lost it) We want to use it to examine and check surfaces for optical applications but it hasn't arrived yet.
I have no problem clamping ceramic and steel knife under the $100 microscope and see the structure with 4x and 10x objective. Though the camera image is not sharp due to stray light reflection, but some can be fixed with photo editing tools. Again, as mentioned in the video, the biggest challenge is the light source and its color spectrum. I am not sure if putting a color filter before the light source will help or not, but it worth a try. A metallurgy microscope should have solved the light and optical problem, but for a price tag of more than $1400 , it is overkill to use it to see the edge of a knife. IMHO, a cheap USB microscope with a glide can already do the job.
I have a stereo microscope (6.3x-50x, optionally up to 100x) and for simply looking onto the knife edge it definitely works. When the purpose is to go into details of material/steel properties etc. then I think a reflecting light microscope as described or maybe even something more complicated is needed.
What do you think of the AmScope ME580TA-PZ-2L ? As you mentioned in another video, any microscope company that advertises 1000x or 2000X is pushing out fake numbers, so can you believe them when they say even more reasonable numbers like 500 or 600?
Thanks for the video, I'm also curious about metallurgical microscopes, as I'm into electronics and interested in looking at silicon dies. Can you use a trinocular microscope like a SW380T as a metallurgical microscope if you shine a strong flashlight into one of the eyepieces? What makes the metallurgical microscopes different? Perhaps some polarized filters on the flashlight and camera could limit stray light?
Standard stereo industrial microscope will do fine for knives. They are not expensive and used in electronics repair, watchmaking and so on. Need ring LED light and 20x+ magnification.
Do metallurgical microscopes come with the option of light through the specimen? Does a metallurgical microscope microscope have disadvantages if it is usef in a through light mode? Can the objectives of a metallurgical microscope be changed to standard objectives to eliminate the disadvantages of a metallurgical microscope for viewing specimens with the light from below?
Hello, Can you me whether ordinary objectives can be on a metallurgical microscope? I have Older Olympus microscope that has the metallurgical attachment (reflected light with beam splitter). Do i have to use Mplan objectives only? Please advise and thank you!
Do you think I could use a inverted metalurgical microscope for seeimg transparent specimens well? Since I don't want to be limited on size and transparency for an all in one microscope?
Thanks very much. I have a problem on my microscope . When i used the 4 object, i see every thing on specimen clear. As well as power 10. But when turn to power 40 not moving the stage i see nothing as well as power 100. So i worried about whether power 40 and power 100 are got dirty or mistakes that I'm doing. I use the eye-peices 18 What problem do i have? When i want to use power 40/100 how could i concentrate to get clear report? If my both powers got dirty how could i know therefore i see the light thanks and appreciate you to make me understand hope to see.
If the 40x / 100x is of a different series, then maybe they are not parfocal and you lose the focus when changing magnification. To check if they are really dirty, take them out and look through them from behind. You can then see if there is dirt on the optics. If too small to see, then use magnifying glass or eyepiece or mobile phone camera and zoom.
You will have to do sample preparation, grinding down to lest say 2000 grit and polishing down to 1 micron and have a very flat surface. Also normally you will have to etch the surface to see the microstructure.
Well damn. I just picked up a huge metallurgical microscope in a junk shop for £20. Probably from the 1970s. It was sold as not working but it only needed cleaning, tuning up and a new bulb. The objectives are perfect
There is a video by electronupdate on how to convert a standard 'bottom up' microscope into a metallurgical microscope.
When we image fluorescent samples, we shine (very bright) light down the light path through the objective onto the specimen, with bounced light coming back through the filters to show only the labelled parts of the specimen. As far as I'm aware, this doesn't require any special design of the objective itself, but you seemed to be implying that objectives for metallurgical microscopes need to be built with a separate light path for the incoming light. Is there a reason for that difference? Is it because you need the incoming light to be at an angle to get useful illumination, or does the incoming light cause noise? E.g., in fluorescent microscope, you filter out all of the excitation light, so you might not see any reflection artefacts caused by the light going down the lens
I recently scored an older Vickers Instruments microscope from an auction for equipment taken from a machine shop. It's designed to be used for both transmitted and incident light microscopy. I agree with your take on the question that a stereo microscope should have sufficient resolution for knife sharpening. I think higher resolution is useful for measuring surface roughness for highly polished surfaces, but I doubt a knife edge is the right application. As an electronics engineer I am looking forward to examining semiconductor devices which have structures in the micrometers.
Hi all
Metallurgical microscope would be nice to have for knife sharpener, however they are built with bit different approach. You need to prepare sample (often with resin), grind it, eatch it and then view it under microscope. With knife sharpening you do not have this luxury to prepare sample, so the best what you can do is with digital single tube microscope or stereo microscope, both build on the same concept.
For this you need good incident lighting with Ra/CRI at about 90 or higher, because you’ll get nasty blue/yellow smears on the image from reflections.
Last but not least, forget to observing the apex of the grind. With good quality grind the apex go below 0.3 um, which is above what light microscopes can deliver, irrelevant of their construction. With light microscope you can see the grind but not the apex. For apex inspection you need minimum laser microscope or even electron microscope. With both of them you need again system to position knife correctly and with electron microscope, big enough tube to fit the whole knife. It is extremely difficult and pricy to find electron microscope that can fit 30 cm sample, and I believe making a sample from your knife is not your choice.
Overall stick with stereo microscope or high mag digital. Buy yourself good and small incident lights, and think about how to position the grind to objective so it can be perpendicular.
I am in a process as well, but sharing my findings. Hopefully someone will read it and consider.
@Olivier great channel I’ve learn a lot from your lectures.
You would also have, all else being equal, higher spherical aberration if viewing a conventionally-prepared slide on a metallurgical microscope. This is because the metallurgical objectives do not compensate for the cover glass.
Would it be possible to mimic a metallurgical microscope with a trinocular microscope by shining a collimated light beam through the camera tube?
Because the top-illumination in a metallurgical microscope is done by means of a beam-splitter anyway.
I myself only have an antique single-tube compound microscope with a mirror so I can't check it out. But I remember that Ben Krasnow from the applied science channel drilled a hole in a cheap microscope and inserted a simple beam splitter to turn it into a metallurgical microscope.
We bought a relatively cheap ($1300 at 50% off) metallurgical microscope from amscope at work. (but ofcourse UPS delivered it to the wrong address and then lost it)
We want to use it to examine and check surfaces for optical applications but it hasn't arrived yet.
I have no problem clamping ceramic and steel knife under the $100 microscope and see the structure with 4x and 10x objective. Though the camera image is not sharp due to stray light reflection, but some can be fixed with photo editing tools. Again, as mentioned in the video, the biggest challenge is the light source and its color spectrum. I am not sure if putting a color filter before the light source will help or not, but it worth a try.
A metallurgy microscope should have solved the light and optical problem, but for a price tag of more than $1400 , it is overkill to use it to see the edge of a knife. IMHO, a cheap USB microscope with a glide can already do the job.
Please bring more videos related to metallurgical microscopes...it will be very help-full for more like me❤️
Please make a video for polarizing microscope...explaining about working and parts...please...humble request 🙏
a good microscop has transobjectiv EPI illumination also for fluorescence and EPI-DIC
I have a stereo microscope (6.3x-50x, optionally up to 100x) and for simply looking onto the knife edge it definitely works. When the purpose is to go into details of material/steel properties etc. then I think a reflecting light microscope as described or maybe even something more complicated is needed.
I work at a steel laboratory and we just use profolemtry, sem and confocals
A metallurgical scope would be amazing though ...
It would be fun to see some knives and compare stereo with compound results on say a straight razor....
This answered my question perfectly. Thank you! I'm sharpening knives!
What do you think of the AmScope ME580TA-PZ-2L ? As you mentioned in another video, any microscope company that advertises 1000x or 2000X is pushing out fake numbers, so can you believe them when they say even more reasonable numbers like 500 or 600?
Thanks for the video, I'm also curious about metallurgical microscopes, as I'm into electronics and interested in looking at silicon dies. Can you use a trinocular microscope like a SW380T as a metallurgical microscope if you shine a strong flashlight into one of the eyepieces? What makes the metallurgical microscopes different? Perhaps some polarized filters on the flashlight and camera could limit stray light?
When you shine light into one eyepiece (and want to look with the other one) then there is much internal light reflection which destroys contrast.
Standard stereo industrial microscope will do fine for knives. They are not expensive and used in electronics repair, watchmaking and so on. Need ring LED light and 20x+ magnification.
Do metallurgical microscopes come with the option of light through the specimen?
Does a metallurgical microscope microscope have disadvantages if it is usef in a through light mode?
Can the objectives of a metallurgical microscope be changed to standard objectives to eliminate the disadvantages of a metallurgical microscope for viewing specimens with the light from below?
You can also heat up the knife until it glows white.
Hello, Can you me whether ordinary objectives can be on a metallurgical microscope? I have Older Olympus microscope that has the metallurgical attachment (reflected light with beam splitter). Do i have to use Mplan objectives only? Please advise and thank you!
Do you think I could use a inverted metalurgical microscope for seeimg transparent specimens well? Since I don't want to be limited on size and transparency for an all in one microscope?
Thanks very much.
I have a problem on my microscope .
When i used the 4 object, i see every thing on specimen clear. As well as power 10. But when turn to power 40 not moving the stage i see nothing as well as power 100. So i worried about whether power 40 and power 100 are got dirty or mistakes that I'm doing.
I use the eye-peices 18
What problem do i have?
When i want to use power 40/100 how could i concentrate to get clear report?
If my both powers got dirty how could i know therefore i see the light thanks and appreciate you to make me understand hope to see.
If the 40x / 100x is of a different series, then maybe they are not parfocal and you lose the focus when changing magnification. To check if they are really dirty, take them out and look through them from behind. You can then see if there is dirt on the optics. If too small to see, then use magnifying glass or eyepiece or mobile phone camera and zoom.
@@MicrobehunterMicroscopy thanks , could share with me a lesson or link that you had talked before on this issue thanks agian
7th comment