You are asking many very good questions, but rather than trying to answer them I'll just give a couple of suggestions. First make a list of what you want to look at and then divide the list into groups using some of these criteria: is it clear or opaque; is it visible to the naked eye or not. Once you begin to see what the major area of interest is you can have a better idea of what type of microscope you need. I recommend that everyone own several.
Second, do an internet search using key words like "using a microscope". Look first at the university sites and manufacturer sites like Olympus, Nikon, or Leica, and avoid commercial sites that are merely on line vendors. I did a quick search before writing this and here is a link I recommend: http://www.micrographia.com/tutoria/mic ... cb0100.htm
lorez
illumination
Re: illumination
It sounds like you need to simplify your goals. If this is your first microscope oil immersion dark field is going to be an expensive challenge. Try again with the search and pick a site that addresses things at a level you understand. There are hundreds of good sites and thousands of bad ones.
I think you could probably get off to a good start with a fairly simple microscope with the basics. If you want to do photography get a triocular microscope with a simple dedicated CMOS digital camera. Not the built-in type, but the attachable one. Eyepieces should be 10X and objectives may be the typical 4,10,40,100X achromats. A mechanical slide holder is good to have and a 1.25NA Abbe condenser will also be part of the package. I don't think a beginner needs to worry about a field iris and Koehler... I know a lot of professionals who don't. Illumination can be of a variety of types, halogen, LED, tungsten, but not the 5W fluorescent bulb. This is not the bulb that makes the specimen fluoresce it is the bulb. They are not dimmable and generally have a rather low contrast image (other factors must be considered).
When you are shopping you have many options. The famous big four, Olympus, Nikon, Zeiss, and Leica are all probably more than you need and then there is the used market... a lot of good stuff for the wary and informed shopper. When it comes to the .com microscope companies keep in mind that they are all retailers. None of them make anything.
Best wishes,
lorez
I think you could probably get off to a good start with a fairly simple microscope with the basics. If you want to do photography get a triocular microscope with a simple dedicated CMOS digital camera. Not the built-in type, but the attachable one. Eyepieces should be 10X and objectives may be the typical 4,10,40,100X achromats. A mechanical slide holder is good to have and a 1.25NA Abbe condenser will also be part of the package. I don't think a beginner needs to worry about a field iris and Koehler... I know a lot of professionals who don't. Illumination can be of a variety of types, halogen, LED, tungsten, but not the 5W fluorescent bulb. This is not the bulb that makes the specimen fluoresce it is the bulb. They are not dimmable and generally have a rather low contrast image (other factors must be considered).
When you are shopping you have many options. The famous big four, Olympus, Nikon, Zeiss, and Leica are all probably more than you need and then there is the used market... a lot of good stuff for the wary and informed shopper. When it comes to the .com microscope companies keep in mind that they are all retailers. None of them make anything.
Best wishes,
lorez
Re: illumination
Hi Lymia,
A biological microscope is one which has the light passing through the object, as most biological material at a size small enough to be viewed by microscope is transparent, some may have colour but most e.g. bacteria are colourless. Texture is an almost meaningless concept when dealing with microorganisms, in the macro world you see things mainly by reflected light where texture, colour and shading is important however with the microscope looking at biological material some method has to be found to form contrast most of these methods have been mentioned.
If you wish to attempt to determine what a particular bacterium is then you will need to do things like culturing, and staining with differential stains.
Köhler illumination was designed to give even illumination across the field of view and the highest possible resolution from the microscope, I would always attempt to achieve Köhler illumination if possible.
If you can afford it I would recommend you get a microscope with differential interference contrast this gives a good and variable contrast while retaining the highest resolution from your optics.
People new to microscopy get hung up on magnification, the thing you most need to look for in a microscope is resolution the magnification is only there to match the resolution of the microscope to the resolution of your eyes if you have poor eyesight then you may want a higher magnification to see the small detail however if your eyesight is good then too higher magnification is only going to look fuzzy.
I hope this helps you but please ask as many more questions as you feel you need, trying to make them specific so we can answer them specifically.
Good luck.
Peter.
A biological microscope is one which has the light passing through the object, as most biological material at a size small enough to be viewed by microscope is transparent, some may have colour but most e.g. bacteria are colourless. Texture is an almost meaningless concept when dealing with microorganisms, in the macro world you see things mainly by reflected light where texture, colour and shading is important however with the microscope looking at biological material some method has to be found to form contrast most of these methods have been mentioned.
If you wish to attempt to determine what a particular bacterium is then you will need to do things like culturing, and staining with differential stains.
Köhler illumination was designed to give even illumination across the field of view and the highest possible resolution from the microscope, I would always attempt to achieve Köhler illumination if possible.
If you can afford it I would recommend you get a microscope with differential interference contrast this gives a good and variable contrast while retaining the highest resolution from your optics.
People new to microscopy get hung up on magnification, the thing you most need to look for in a microscope is resolution the magnification is only there to match the resolution of the microscope to the resolution of your eyes if you have poor eyesight then you may want a higher magnification to see the small detail however if your eyesight is good then too higher magnification is only going to look fuzzy.
I hope this helps you but please ask as many more questions as you feel you need, trying to make them specific so we can answer them specifically.
Good luck.
Peter.
Re: illumination
Let me suggest the following (I know you or others will disagree or have already expressed different opinions, but I'm trying to keep things simple since you are starting in this wonderful hobby).
1a. As I suggested earlier, please read:
http://www.microbehunter.com/the-beginn ... icroscopy/
1b. Please also read useful advice about camera resolution:
http://www.microbehunter.com/required-c ... icroscope/
2. Which microscope? something similar to (not necessarily that one or an identical one-- but just to give you an idea of what I think would be suitable):
http://www.microscopenet.com/40x2000x-c ... -9815.html
3. Which camera? A USB camera (3 Mpx is sufficient if you want to post to the web or view the images on the computer monitor-- no advantage to higher Mpx unless you want to crop the images significantly or make prints, I think; a 5 Mpx camera would also be good but will cost more):
http://www.microscopenet.com/32mp-digit ... 10007.html
I'm no authority on the subject, but I believe something like the above might well be a good choice for a beginner and will provide excellent optical quality at a relatively low price. In a few years, you will know exactly what you want and can then upgrade. Koehler illumination is not needed (I almost said not desirable) at this time. You don't need a "dry" darkfield condenser (you can make darkfield stops for that purpose easily), but if you are mainly interested in observing bacteria under darkfield conditions, then an oil darkfield condenser with an appropriate objective will be necessary; but if you want to study bacteria seriously, then please read again what Peter said above.
1a. As I suggested earlier, please read:
http://www.microbehunter.com/the-beginn ... icroscopy/
1b. Please also read useful advice about camera resolution:
http://www.microbehunter.com/required-c ... icroscope/
2. Which microscope? something similar to (not necessarily that one or an identical one-- but just to give you an idea of what I think would be suitable):
http://www.microscopenet.com/40x2000x-c ... -9815.html
3. Which camera? A USB camera (3 Mpx is sufficient if you want to post to the web or view the images on the computer monitor-- no advantage to higher Mpx unless you want to crop the images significantly or make prints, I think; a 5 Mpx camera would also be good but will cost more):
http://www.microscopenet.com/32mp-digit ... 10007.html
I'm no authority on the subject, but I believe something like the above might well be a good choice for a beginner and will provide excellent optical quality at a relatively low price. In a few years, you will know exactly what you want and can then upgrade. Koehler illumination is not needed (I almost said not desirable) at this time. You don't need a "dry" darkfield condenser (you can make darkfield stops for that purpose easily), but if you are mainly interested in observing bacteria under darkfield conditions, then an oil darkfield condenser with an appropriate objective will be necessary; but if you want to study bacteria seriously, then please read again what Peter said above.
Re: illumination
Lymia, Lorex, Peter, and Gekko have given you excellent advice and sites to look at (and study).
Oliver, and many other sites offer great advice on what to consider in a microscope.
My two cents, I bought an Amscope - B120 with the upgraded 3MP USB camera and am not disappointed. Inexpensive, very good quality, upgradable, and should keep you happy for quite a few years.
Before this I was an amateur astronomer. I didn't start out with the telescope I finished with. Part of the enjoyment is learning and upgrading as you go.
Good luck. Bonne chance.
Oliver, and many other sites offer great advice on what to consider in a microscope.
My two cents, I bought an Amscope - B120 with the upgraded 3MP USB camera and am not disappointed. Inexpensive, very good quality, upgradable, and should keep you happy for quite a few years.
Before this I was an amateur astronomer. I didn't start out with the telescope I finished with. Part of the enjoyment is learning and upgrading as you go.
Good luck. Bonne chance.
Re: illumination
THREE HUZZAS FOR YOU LYMIA,
Now that you have done your home work you are ready to pick a system that is going to get you off to a good start. That's where the fun starts. Since you are pretty sure you are going to get the 100X oil dark field set I will tell you that my favorite bacteria using dark field is the spirochete. It squiggles.
lorez
Now that you have done your home work you are ready to pick a system that is going to get you off to a good start. That's where the fun starts. Since you are pretty sure you are going to get the 100X oil dark field set I will tell you that my favorite bacteria using dark field is the spirochete. It squiggles.
lorez
Re: illumination
lorez wrote:my favorite bacteria using dark field is the spirochete. It squiggles.
Re: illumination
lorez wrote:
my favorite bacteria using dark field is the spirochete. It squiggles.
Yes, and some of them move across the field of view like a bullet!
Peter.
my favorite bacteria using dark field is the spirochete. It squiggles.
Yes, and some of them move across the field of view like a bullet!
Peter.