How to use a microscope and oil immersion

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  • Опубликовано: 24 дек 2024

Комментарии • 272

  • @Girlygiggles3
    @Girlygiggles3 11 лет назад +26

    This is one of the most thorough and helpful videos I've ever seen on RUclips. I don't know who this woman is, but she is an amazing teacher.

  • @CoolBeansUchiha
    @CoolBeansUchiha 3 года назад +17

    This was very informative and clear! I am a college student taking microbiology and this helped make things more clear to me than reading from the manual. Thank you for this! :)

  • @Sharpie22ish
    @Sharpie22ish 11 лет назад +33

    Love this. You're an amazingly thorough professor! Thank you for publicly posting this for all to watch!

  • @princeardalan
    @princeardalan 11 лет назад +1

    I thank you very much for teaching us how to do it. We have very stupid lecturers, very stupid demonstrators and they never showed us how to find a bacteria and how to do the the oil immersion. please keep posting videos like this.

  • @mabelhartman2039
    @mabelhartman2039 2 года назад +2

    I'm in HOSA and using a microscope with oil immersion is one of the skills we have to learn. I found this really helpful to visualize the procedure. Thank you!!

  • @discusdivana7581
    @discusdivana7581 3 года назад +1

    Thank you dearly for this video. It is 10 years later but you are teaching me now. I am on a mission to help our aquarium industry in South Africa, and your video contributes to it. Much love and thanks.

  • @sadekgheidan
    @sadekgheidan 8 лет назад +60

    Whoever is in her class is lucky as "heck" :p
    Lovely scientist/teacher/lady & very informative *and clear* video! Thank you pro.

  • @kaleyhilliard102
    @kaleyhilliard102 8 лет назад +72

    I like how your shirts are the color of Saffranin and Crystal Violet. Nice Touch! :-)

  • @danfuerthgillis4483
    @danfuerthgillis4483 5 лет назад +21

    Lol I like her "Do it or get out" approach lmao. We need to get this old school training back 😂😂😂. Easy video to follow.

  • @cwldoc4958
    @cwldoc4958 2 года назад

    Excellent lecture, thank you for posting! I've looked at other youtube videos on this subject and they tend to raise more questions than answers.

  • @carolinakroger3089
    @carolinakroger3089 8 лет назад +10

    I really appreciate your sharing of the little trick about focusing the light condenser, you save my day, thank you so much!!

    • @TheMsMarmot
      @TheMsMarmot 7 лет назад

      4Carolina Kroger

    • @warlitaibrahim5178
      @warlitaibrahim5178 3 года назад

      Yes to learn how to use mashine it is very useful to us znd we learn about where the oil put up and how the mashine clean.

    • @warlitaibrahim5178
      @warlitaibrahim5178 3 года назад

      Very useful in xhiwing each part of mashine

  • @timeslidr9063
    @timeslidr9063 7 лет назад +42

    I'm not even a student but I watched the whole thing.

  • @ashuntu2010
    @ashuntu2010 12 лет назад

    This is a highly detailed demonstration for using a microscope in a perfect way. I am a chemist and I have never used light microscopes ever in my life but in my research I need to use them a lot and a lot.. I have been searching videos like this on youtube to get familiar with the proper working of the microscope. I am really thankful to the instructor of this video for uploading this nice video.. Cheers!!!!! and Thanks a lot !!! :) :)

  • @dezidezi2184
    @dezidezi2184 12 лет назад +2

    this addressed a lot of the problems I was experiencing in class. Thank you for your videos!

  • @chascodelviso
    @chascodelviso 11 лет назад +2

    Very useful! I'm using a microscope at home with my kids, and even though I have some experience in microbiology, you gave some great pointers! Thank you

  • @mustafanakipoglu4278
    @mustafanakipoglu4278 7 лет назад +34

    Her students are lucky. Many teachers are not that dedicated and therefore you may see their students working in an institution or company while they cannot even use a microscope properly!

  • @RajaRamGurungRaza
    @RajaRamGurungRaza 3 года назад

    This is one of the clear and detail instruction to use microscope correctly.

  • @BLDUBMUSIC
    @BLDUBMUSIC 10 лет назад +33

    DONT FUCKING GO TO 40 GUYS!!!

  • @paulaujla2151
    @paulaujla2151 4 года назад

    Just received my new microscope and found this video...the instructions with my Swift microscope are very basic and your video has helped me understand how to use all the components and accessories. Excellently informative video - thank you :o)

  • @ceasarandrepont5331
    @ceasarandrepont5331 Год назад

    Thank YOU! Watching your demonstration made the procedure easier. Now, all I have to do is retain and recall the process.

  • @gmikeg123
    @gmikeg123 8 лет назад +1

    Thank you for the tutorial. I recently purchased a microscope, but it came with no documentation, so your video helped to give me a lot of needed information. I appreciate you taking the time to do this.

    • @combativejake82
      @combativejake82 8 лет назад

      Hey I have a quesstion and since you're the first comment can you answer a question for me? in 9:22 She said dabbing it with a can wipe or something like that. Did i mishear? If so what kind of wipe do you have to dab it with?

    • @teeee9313
      @teeee9313 8 лет назад +1

      Hi, it's a Kim Wipe, which is essentially just a lintless tissue.

    • @combativejake82
      @combativejake82 8 лет назад

      thanks

    • @warlitaibrahim5178
      @warlitaibrahim5178 3 года назад

      Thanks for tutyrian online. Can improve to individual.

  • @ace53458
    @ace53458 11 лет назад +4

    Very thorough. Extremely helpful. Thank you for uploading!

  • @maryrus7493
    @maryrus7493 5 лет назад +2

    Thank you so much for the details and the clear instructions how to use microscope to find the bacteria, fast . And thanks for your encouragement not to frustrated. But try hard , and to draw a circle, because the bacteria are so small, can’t be seen by naked eyes. And remember to put immersion oil only with 100x and lean focusing with fine knob.. you are amazi. I appreciate your explanation .

    • @bioprofaz
      @bioprofaz  5 лет назад

      Awesome! Good luck with your lab!

  • @thecatlover8889
    @thecatlover8889 11 лет назад +2

    Great video! I'm taking Microbiology now and watch the videos before going to lab. Very helpful! Thank you for posting:)

  • @deborahernandez44
    @deborahernandez44 4 года назад

    This was helpful! I’m in microbiology at the moment and had a little trouble working the oil lens. This made it more clear on what to do if I lost the focus.

    • @bioprofaz
      @bioprofaz  4 года назад

      Debora Hernandez I’m glad this was able to help you. Good luck in your class!

    • @warlitaibrahim5178
      @warlitaibrahim5178 3 года назад

      Ut must be fucost to use maschine .

  • @oxiroxt1196
    @oxiroxt1196 10 лет назад +9

    Great teacher

  • @emilylowman9088
    @emilylowman9088 8 лет назад +2

    Thanks for the video! I will now be well prepared for my lab tomorrow :)

  • @tartanhandbag
    @tartanhandbag 6 лет назад +2

    glad the advice in the video is explained in no uncertain terms. important to be very clear with these fundamentals, which are often difficult for students to grasp, myself included. microbiology is hard and it pays to be meticulous and really consider as many aspects of your technique as possible. you might think people are just being anal but, when you realise why, it usually makes sense.

  • @veetown9036
    @veetown9036 4 года назад

    Really good explanations and tips. I did Biology in my undergrad but I wish that you were my lecturer back then. Thanks

  • @newtonmagaya6590
    @newtonmagaya6590 7 лет назад

    you are the kind of teacher who makes understanding possible

  • @sierrahyker
    @sierrahyker 6 лет назад +4

    Very good presentation. Wish you had been my Micro teacher! Love the details.

  • @emremicrosoft5321
    @emremicrosoft5321 Год назад

    Best description teacher 👍🏻 thank you very much, indeed.

  • @punkybrewstar83
    @punkybrewstar83 8 лет назад +31

    What a great lady. Thanks for doing this. Our teachers for this particular subject are very organised and helpful in general(hence the link to your video), but there are so many of our teachers who are not. Really chuffed and grateful that you cared enough to make this, and that you are able to demonstrate that you know about what you are teaching, and that you care about your students. Whilst the lecture at the beginning might not be important for those outside of your class, for me it demonstrates that you communicate, outline expectations, provide information and opportunities to master skills. I even bet all of your assessments come complete with marking schedules and correct answers that you use to mark them with, and you probably provide feedback. This is a novelty at our university apparently despite the HUGE EXPENSE. Anyway... thank you :) Do you teach vet clinic practice at all?

  • @1970DaddyBig
    @1970DaddyBig 12 лет назад

    This is exactly what I needed for me and my daughters to learn how to use the 100x objective lense and oil immersion. This only thing left out is whether to use oil/b or oil/a.

  • @jonathanvezina5349
    @jonathanvezina5349 11 лет назад

    Thank you. I am not a biologist or a microbiologist but I am fascinated with the subject. I purchased a very nice Omax digital microscope and your videos are extremely helpful for the self learner.

  • @electronicsNmore
    @electronicsNmore 10 лет назад +6

    Great job with the video!

  • @ull893
    @ull893 10 лет назад

    A very special thank you for this video and also for the gram stain video. Invaluable resource for a beginner student. Thank you .

  • @levischmidt4559
    @levischmidt4559 3 года назад

    Her students are so lucky to have a teacher that great!

  • @emmabrandau6093
    @emmabrandau6093 9 лет назад

    Super helpful videos for Micro! Thank you!

  • @jessi5944
    @jessi5944 5 лет назад

    I have such a problem with oil immersion! My professor won't help us focus it anymore, so I'm trying to learn on my own! I can find it on every objective but oil immersion. Trying to find out what I'm doing wrong. Thank you.

  • @goatcheeseburger
    @goatcheeseburger 11 месяцев назад

    Wish i had an instructor who can give directions as clear as her.

  • @inner.aloha.matters
    @inner.aloha.matters 8 лет назад

    much aloha! I have a skills test and this is my first time using a microscope this semester! This made me a lot more confident and comfortable! Mahalo from Hawaii ^^

  • @joshuaadedipe2284
    @joshuaadedipe2284 2 года назад

    Oh! This tutorial is brilliant. Thank you.👍🏼

  • @letzsee9
    @letzsee9 12 лет назад

    Thank you so much!! This is very helpful. Now I'm ready for practical test tomorrow :)

  • @Orexll
    @Orexll 13 лет назад +1

    BEST tutorial I'm seen so far on youtube, thx

  • @stacystacy754
    @stacystacy754 4 года назад +2

    She explained it very well, but I would still be afraid to have her as a professor because I'm a bit slow, the beauty of videos is that you can rewind them lol

  • @yeppy013
    @yeppy013 6 лет назад +1

    So again the bacteria is facing up and the labeled with sharpie is facing down while viewing under oil immersion, correct?

  • @Lyndell44
    @Lyndell44 12 лет назад

    Wonderfully detailed overview! Brava!

  • @awaismehmood03
    @awaismehmood03 5 месяцев назад

    One of the best videos I’ve watched helped me pass ❤

  • @1999Paulus
    @1999Paulus 11 лет назад

    I know it would be boring for you, but could you not make a video about the basics of how to use a microscope for us who use it more as a hobby? It is not everyday I find a teacher that is so clear. Great work.

  • @maxfine6549
    @maxfine6549 12 лет назад

    Thank you my grand father who is a scienceist got my a microskopt like this for my 12 birth day
    (augast 20 2012) and i just set it up and he and I didnot now how to applie the oil
    and now we do thank you very very much.

  • @BAXLEY-TINA
    @BAXLEY-TINA 10 лет назад

    Thank you! Very instructive and thorough!

  • @jaejae2490
    @jaejae2490 6 лет назад

    Thank you so much! I am studying without classes which makes life difficult sometimes. This was very helpful!

  • @kainoa82858
    @kainoa82858 5 лет назад +6

    Thank you! I'm not in your class, but this is a great tutorial!!!

  • @Tw1zzl3rs
    @Tw1zzl3rs 4 года назад

    Thank you for the loop trick! I had no idea!

  • @djeupaghislain6649
    @djeupaghislain6649 8 лет назад +2

    thank you for this explanation. very helpful

  • @koptischerwr4582
    @koptischerwr4582 10 лет назад

    Awesome vid. Very helpful. Thanks!

  • @Applepie19821
    @Applepie19821 5 лет назад

    Thank you so much!!! This really helps a lot for my practical exam !!

  • @thesoupdragonat121
    @thesoupdragonat121 7 лет назад

    Superb lesson, many thanks.

  • @Jules7892
    @Jules7892 13 лет назад

    I had 3 Biologies in Ontario Collegiate Studies of CANADA!! My 1st MicroScope Lab Instrument was in Grade 10 Biology,then Grade 11 Biology & Finally Grade 13 Gold Honourary Collegiate ,Ontario,Sciences.Although I was already familiar with with my Laboratory $300.00+Taxes Edmund Scientific 3 Achromatic-MFg Multi-Coated Objective Instrument, I only got my SUPERB-Lab KONUS ACADEMY with Laboratory with "Oil Immersion in May of 2011! Today,Ontario,CANADA Biologies are Grades,10,11,12.Grade13removed!!

  • @billavara
    @billavara 9 лет назад

    Thank you for this lecture. I found it really useful.

  • @michaelarungwa6507
    @michaelarungwa6507 Год назад

    I never knew of the looo thing, thank you so much

  • @____.__._.._
    @____.__._.._ 4 года назад

    is that simplified Koehler ilumination? (3:48)

  • @thepeach12345
    @thepeach12345 4 года назад

    Thanks you saved me a class, I can do this at my house on my own time. well done

  • @evanbrown6923
    @evanbrown6923 4 года назад

    Question, why do you advise against Kimwipes for the lenses? My understanding was that they were made for such things, and many manufacturers even recommend them.

    • @bioprofaz
      @bioprofaz  4 года назад

      We used them because they are designed for lenses, and we wanted to do everything we could to keep them from getting scratched.

    • @evanbrown6923
      @evanbrown6923 4 года назад

      @@bioprofaz Thank you for the response! Everything I find online said Kimwipes are made for cleaning sensitive equipment and optics, regardless thanks to you I went ahead and bought some proper lens paper. The $5 is negligible when compared to the cost of a new objective. With that let me just say thank you for making these videos, they're highly informative and very well made. Just know your work is highly appreciated and I look forward to seeing what you have planned for the future.

    • @bioprofaz
      @bioprofaz  4 года назад

      @@evanbrown6923 Thanks for the kind words. I have to laugh when someone compliments me on my videos or asks me questions. I made these for my students as a pre-lab activity and never intended for anyone else to watch them. I resigned from teaching to start a business a few years ago. Its called BACK for Learning. Check out my website some time www.backforlearning.com/. I am still in the start-up stage of my business, but plan to expand with more kits, curriculum, books, and videos.

    • @evanbrown6923
      @evanbrown6923 4 года назад

      @@bioprofaz That's amazing! Just subscribed to the newsletter. You're a great professor, very knowledgeable and concise without seeming even the least bit pretentious like some professors can tend to be. I would love to be one of your students, though I'm looking for something a bit closer to High School/University level like what's presented in your videos. Your videos are perfect for people like me who have a desire to learn as much as possible, but without being enrolled in University for the rest of my life.(I'm a computer science major, who's never taken anything beyond High School Biology.) Biology is a passion of mine however, and I even have a small home laboratory for practicing various scientific disciplines. I've only just gotten a decent microscope so now I'm working on gathering various supplies. I would love if you could help provide some guidance.

    • @bioprofaz
      @bioprofaz  4 года назад

      @@evanbrown6923 I am so jealous! I want a home lab. That is very cool! Yes, of course, I will give any guidance I can. I miss being in the lab.

  • @agnalajumbe189
    @agnalajumbe189 9 лет назад +3

    That was nice & helpful..thanks a lot...

  • @ODPILOT
    @ODPILOT 8 лет назад +6

    With oil immersion microscopy - do you add the oil directly to the fixed microscope slide or do you use a cover plate - or can you do it either way? Thanks

    • @markcarter6333
      @markcarter6333 7 лет назад

      Wish you would take her class... Replay the vid.
      Put oil on top of fingernail, then place finger under lense, raise platform with finger until it touch lense. Keep raising platform until you can see cells in finger.

    • @itebeen8049
      @itebeen8049 5 лет назад +1

      @@markcarter6333 Tf u talkin bout

  • @djjoel1
    @djjoel1 5 лет назад +1

    I'm so glad I watched this before buying replacement objectives... it's working now! :D

    • @bioprofaz
      @bioprofaz  5 лет назад

      That is very cool!

    • @warlitaibrahim5178
      @warlitaibrahim5178 3 года назад

      In wacthing the machen is the guide to learn on how to clean and how do we use it the maschine

  • @masoodahmed9432
    @masoodahmed9432 9 лет назад

    Very nice teacher

  • @donnaguthrie3339
    @donnaguthrie3339 6 лет назад +3

    I wish my professor helped me like this video did. I can't wait to go to lab and try it. I only spent 2 freakin hours looking at slides without seeing anything! And my professors tip "walk away and come back to it, its there, you just aren't looking good enough" seriously?!

  • @shahmalakumaran3696
    @shahmalakumaran3696 4 года назад +1

    Thank you so much. I feel like a pro after watching this video.

    • @bioprofaz
      @bioprofaz  4 года назад

      Aw, I’m so glad!

    • @warlitaibrahim5178
      @warlitaibrahim5178 3 года назад

      In watching how to clean each part and how to use its so very useful to both msle and female.

  • @kuhataparunks
    @kuhataparunks 8 лет назад

    How did you know that I am in microbiology??? That's why I am watching this! thanks for the video it was very informative

  • @teresashinkansen9402
    @teresashinkansen9402 4 года назад

    I been watching many tutorials about how to use the oil immersion objective but no one (not even at my school) put oil between the condenser and the slide, i learned about this some time ago, you need to do this to have maximum resolution and get a serious benefit about using the oil immersion objective, if you not do this you are going to be limited by the numeric aperture of the condenser which will be always below 1.

  • @raindroprainbow9459
    @raindroprainbow9459 5 лет назад

    I usually have trouble finding bacteria. Do you think you could show us what to look for at the main objectives, 4x,10x, 40x, and 100x, and what exactly it looks like under the microscope? I’ve been told to look for grains of sand? If there is a certain way to prepare the slide, could you also include that? This would seriously be a great help!

  • @aneesurrehman7405
    @aneesurrehman7405 10 месяцев назад

    You are brilliant maaam

  • @EeccmanNL
    @EeccmanNL 11 лет назад

    i didnt get the thing what you where doing in the beginning with the focus on the loop, what exactly do i adjust ) my english is not that good )

    • @patarthenry
      @patarthenry 11 лет назад

      I believe she says: you focus the condenser. When the loop comes into focus, then the condenser is in the right place. After this step, you have to refocus the slide with the eyepiece adjustment knob.

  • @firstchirriru
    @firstchirriru 6 лет назад

    Thank you Ma'am! your the best!

  • @CNPdubyagirl
    @CNPdubyagirl 11 лет назад +1

    LOVE LOVE LOVE...!!! from a teacher who has no idea how we didn't destroy every single microscope we had in college. Master teacher, Thank You Dear = WOW

  • @georgep.sartianom.d.4118
    @georgep.sartianom.d.4118 7 лет назад +1

    Luckily, the lenses being parfocal, you can swing in the oil immersion lens when the specimen is in focus at 400X, and be close to having the field in focus at 1000X. Modern day microscopes allow for this because they are made very precisely, even if the individual objectives have been screwed in randomly in the holes on the nosepiece. This has not always been so, and if you were using an apochromatic objective and swung it into place, and you scratched it, you might be out a few thousand dollars.
    It is safer to place a drop of oil on the specimen when the object in question is in focus at 400 X and is centered in the field, and then lower the stage well below a potential scraping level, and swing and click the 100X lens into position - and then lower the oil immersion lens slowly while observing from the side of the microscope. When the surface of the oil immersion lens makes contact with the oil, there will be a flash of light. The lens will then have become properly immersed, and only the fine adjustment will be needed for focusing. Scraping and scratching of the turret lens will have been avoided. At that juncture, only the fine adjustment should be used - it should have built-in slippage if you go too far and compress the slide.
    Most microscopes now also have a lock ring on the outer rim of the coarse adjustment. When the oil immersion lens is in focus, rotate the lock-ring until it is snug, and the coarse adjustment, if mistakenly used, will not be able to lower the body of the microscope and objectives any farther than the locked position, again avoiding the error of cracking a slide or coverslip by using the coarse adjustment when within focusing distance with the oil immersion lens. It might be useful to adjust all microscopes in the lab beforehand to take advantage of this feature and prevent damage to slides or oil immersion lenses.
    The focal length of the 100x lens is etched on the barrel of the lens - it is usually in the range of 1.7mm or so. However, in actuality, it is smaller than the calculated range, which itself is based on a formula which assumes that the objective has only one lens; in actuality, it has several, and the true focal distance is smaller than the rated distance. If you have to turn the fine adjustment more than a fraction of a millimeter in the downward direction and your object has not come into focus, it is time to back off and start over.

  • @a-ra-m4596
    @a-ra-m4596 8 лет назад +1

    why using the oil imersion in the center of the slide when use the 100x lens

  • @soulaphilippe8234
    @soulaphilippe8234 6 лет назад +2

    Well done !
    Thank's for your trick about the right condenser distance, I will use it
    and thank's again for the oil cleaning demonstration
    I kiss you
    Philippe

  • @912530670
    @912530670 11 лет назад

    What happens if you open and close the iris diaphragm when using the oil immersion objective?

  • @mariatate6769
    @mariatate6769 8 лет назад

    I wish you were my mother or instructor because you're awesome! Anyway, I'm looking to purchase oil immersion for my microscope. (I'm considering to purchase a AmScope Microscope with digital cord to PC hook up and a magnification of 2500x .) Had I not watch this video ,man,I would be regretting using 100x with oil immersion. I didn't know you damage your objective with oil immersion. Thank you so much .

    • @sacadmukhtar7152
      @sacadmukhtar7152 8 лет назад

      I'm going to buy a microscope ..Please any advice ?? in amazon I found many different of them and got confused !! want to use it for ecological studies.

  • @freedumenergy2440
    @freedumenergy2440 7 лет назад

    Great video prep but i dont have a scholarship but I just bought a microscope, and I learned quite a bit just now..

  • @kwelyroos71
    @kwelyroos71 7 лет назад

    You'd LIKE me! I have my OWN stains, MY OWN scopes (compound AND dissection) and I frequently USE both. I also am goingto teach myself HOW to use immertion oil.

  • @NiGoR93
    @NiGoR93 10 лет назад

    This is really really helpful! Thank you for this video...i look forward for more :)

  • @Nhan01
    @Nhan01 13 лет назад

    my heart jumped a little when you said getting oil on the other lenses would ruin the microscope

  • @christinabuxton3758
    @christinabuxton3758 10 лет назад

    Thank you, this was very helpful!

  • @lemoncola1164
    @lemoncola1164 6 лет назад

    if the oil gets on the other lenses, the damage isn't permanent if you send it to a professional to clean it. this is expensive though and it would probably be cheaper and easier to buy a new one each time which is also very expensive, so just dont get it on the other lenses

    • @kpfernandico
      @kpfernandico 5 лет назад

      Wont the oil be romved using 90% ethanol and lens paper to wipe it off? Im kinda scared of practicals now

  • @hasankorucan5386
    @hasankorucan5386 9 лет назад

    bioprofaz MY 40X lens had touched the oil before I watched this video. Now what should I do to clean it? It's was a "Olympus Optical Co." immersion oil. Is xlene suitable for cleaning?

    • @sadekgheidan
      @sadekgheidan 8 лет назад

      Sorry to hear that :\ so what did you do?

  • @Cubanuel
    @Cubanuel 12 лет назад

    Thank you so much! you are wonderful.

  • @Casting4Growth
    @Casting4Growth 11 лет назад

    Great Video...Very informative

  • @anahifuentes6403
    @anahifuentes6403 10 лет назад +50

    You look like a teacher that i wouldnt like but good info!! Lol

    • @jacquelinevictor3829
      @jacquelinevictor3829 6 лет назад

      part of compound microspe

    • @hellfirepictures
      @hellfirepictures 6 лет назад +5

      And I'm sure she's glad you're not her student, as you make such stupid comments.

  • @kevjumbaz
    @kevjumbaz 6 лет назад +1

    remember to turn the light up at high power!

  • @vanessawhyte6856
    @vanessawhyte6856 6 лет назад

    Very informative, thank you😊

  • @saadalmissallaty90saad64
    @saadalmissallaty90saad64 6 лет назад

    Thanks that was really helpful

  • @bharathraj5862
    @bharathraj5862 6 лет назад

    Thank you very much Madam.
    Please do videos like these

  • @NSS9749
    @NSS9749 3 года назад

    Perfect! Thank You.

  • @goneboating123
    @goneboating123 10 лет назад

    is oil recommended for all items to be examined with 100x...even if they move?
    thanks

  • @frankvet1
    @frankvet1 3 года назад

    No cover slide?