[A. Cemal Ekin] over on PetaPixel reviewed the Apexel 200X LED Microscope Lens. The relatively inexpensive accessory promises to transform your cell phone camera into a microscope. Of course, lenses that strap over your phone’s camera lens aren’t exactly a new idea, but this one looks a little more substantial than the usual piece of plastic in a spring-loaded clip. Does it work? You should read [Cemal’s] post for the details, but the answer — as you might have expected — is yes and no.
On the yes side, you can get some pretty neat photomicrographs from the adapter. On the negative side, your phone isn’t made to accommodate microscope samples. It also isn’t made to stay stable at 200X.
[Cemal] found the same sort of things we’ve found with other similar adapters. You need to zoom to fill the frame with the microscope’s image. Otherwise, you get an odd round image with darkness all around it. The microscope works best on something flat and has a very shallow depth of field, so anything poking in our out will probably be out of focus.
The unit did, however, look substantial and had a built-in rechargeable battery and an LED light. None of the photomicrographs looked bad, but you have to remember that you can’t really use it unless what you want a picture of is flat, and the camera can essentially lay flat on it.
Could you use this with an old phone and rig up a holder to make it better? Probably, but with the focal point basically being the back of the phone, it wouldn’t help much. Microscopes are relatively cheap these days so maybe put the $40 towards a better instrument.
If you have a DSLR, you might think about a 3D-printed microscope lens adapter. Or, go big and build a full-scale open source microscope.
Lab microscopes need oil immersion to work at 100x due to properties of light and refraction or some other science stuff. 200x seems unpossible.
That’s 200x in MU, aka Marketing Units.
It can be anything the seller wants it to be.
20X at best judging by the quarter dollar shot.
Usual marketing wank™
But then you digital zoom 10x and you’re at 200x!
200x exaggerated
Huh? A microscope has an objective lens and an eyepiece, with the final magnification being the product of the magnifications. While a 100x objective may require oil immersion, even “toy” scopes achieve 300x (probably using a 10x eyepiece and 30x objective.) Depending on how the external lens interacts with the lens already in the camera, plus the usual “well, it’s an 8 megapixel image and if you display it on a 60inch 4k monitor that provides another step of magnification”, 200x doesn’t seem THAT far out of reach…
You are forgetting about the ocular lens. With a primary objective of 20x, the total magnification at the ocular is 20x * 10x = 200x.
No, it’s the same as telescopes sort of. Everyone wants to know magnification and you can make that arbitrarily large with different eyepieces but that doesn’t change the underlying aperture size or usable info collected. But making a crappy low signal low contrast image “bigger” just gives you a bigger image with same signal to noise and it’s just as useless. The stage optics are limited to 100x for reasons stated (something something wavelengths of visible light something something index of refraction) and eyepieces enlarge that but is not particularly useful. It is same as if you take a low res photo and or project it on a wall at a meeting or something. It’s just a larger low res image that is jut as crappy.
Alternately, amplifying a crappy MP3 to “louder” results in something just unintelligible.
Oil immersion is more like 1000x or higher. It is also about keeping the lens (due to the refractive index of the oil) a little further away form the sample and not crushing it.
I bought a device similar to this one and can say most definitely that it has major suckage.
You can blow it up with a projector to the side of a building that doesn’t make it a 100,000x magnification. And I’ve seen plenty of path slides blown up to lecture screens- they are all just as blurry and just as crappy as they look under a microscope. The signal to noise is set by the microscope stage optics, not the eyepiece. That is limited to like 100x and requires oil. Unless I need to go tell all my pathologists they are doing it wrong.
In any case there is no way this POS somehow discovered new optics that a pathologist’s teaching and diagnostic microscope hasn’t figured out.
Tracing the track of subatomic particles in film emulsions, including the depth by focus following. No oil until 500 or 1000. Or are you talking about a 100x objective and 10x eyepiece? The magnification of the microscope in that case is 1000 and yes, use oil, and I’m lost with the mixed terminology in the postings.
Speaking solely from the clinical microscopes I use and see in use. Saying magnification for a microscope is objective x eyepiece is not how it’s reported in clinical images it is *only the objective. And 100x is maximum. That’s because after that the “magnification” is arbitrary. If you get rid of the physical eyepiece all together and use a digital camera to a screen, then what is the “magnification” if you define it as objective x eyepiece? It would depend on how big your screen is. It isn’t a thing. And like I argued before if you project it in an auditorium then the “magnification” would be enormous. Another thought experiment. Print that micrograph in a book thumbnail sized or full page. Does that mean the full page one is 10x more “magnified?” Nope. In allllll these cases it is still 100x ie the power is the objective lens. That is how magnification is defined and reported clinically in figure captions and so on.
My passing interest in astronomy is a similar thing- most people don’t really claim magnification and it’s a buzzword for Uber-noob because the power of the eyepiece sets magnification but it is the physical properties of the instrument that determine how much actual information or signal to noise is collected. You can make magnification as arbitrarily large as you’d like (within limits) but the image doesn’t get “better” because you are magnifying noise the same as image.
Finally in audio work if you amplify a garbage recording you get a louder garbage recording, not a somehow magically now-intelligible recording.it’s all the same principle and my original comment was there is no way this device in the article can magnify 200x its marketing. We all know digital zoom is a marketing lie.
Cheers
So it would make a decent dermoscope?
I don’t need one of these, because I have a sports car.
And bugs on your teeth…
If a human hair is approximately 50um, then, at 200x magnification, it’d look larger than a pencil (about 1cm dia.)
Having used a similar device, the only way they are likely to reach that magnification is with a digital zoom.
However, for the right use cases, these microscopes are still quite useful.
You mean for the right cases? Or the right uses?
Yes, yes and both.
I see the doubts in the comments but I built/3D printed both the 100x and the 350x smartphone microscopes from PNNL back in 2014. While I am aware of marketing speak, I also know that it is possible and with a fairly great degree of quality from off the shelf parts for under $10.
https://www.pnnl.gov/available-technologies/pnnl-smartphone-microscope