Calculating monitor magnification- no intermediate lens
Calculating monitor magnification- no intermediate lens
I tried to calculate the total magnification that I'm viewing on my computer screen with a camera as described in this link:
https://www.microscopeworld.com/p-3375- ... ation.aspx
However, I don't think that my calculation was correct.
Objective magnification: 40x
Computer monitor: 711.2mm (28")
Sensor size: 21.6mm on the diagonal (MFT)
Adapters: MFT to c-mount AND c-mount camera adapter for Nikon microscope with ISO 38mm pot
(neither adapter has an intermediate [reduction] lens)
So the equation, according to the link, would be as follows:
Objective Magnification x C-Mount Adapter Magnification = Optical Magnification
40x1= 40
Screen Size / Sensor Size = Digital Magnification
711.2/21.6= 32.93
Optical Magnification x Digital Magnification = Total Magnification
40x32.93= 1,317.2
This doesn't seem to be correct to me. What am I missing here?
https://www.microscopeworld.com/p-3375- ... ation.aspx
However, I don't think that my calculation was correct.
Objective magnification: 40x
Computer monitor: 711.2mm (28")
Sensor size: 21.6mm on the diagonal (MFT)
Adapters: MFT to c-mount AND c-mount camera adapter for Nikon microscope with ISO 38mm pot
(neither adapter has an intermediate [reduction] lens)
So the equation, according to the link, would be as follows:
Objective Magnification x C-Mount Adapter Magnification = Optical Magnification
40x1= 40
Screen Size / Sensor Size = Digital Magnification
711.2/21.6= 32.93
Optical Magnification x Digital Magnification = Total Magnification
40x32.93= 1,317.2
This doesn't seem to be correct to me. What am I missing here?
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Re: Calculating monitor magnification- no intermediate lens
I think your calculation is correct, but as you've noticed the number seems ludicrous. That's because calculating magnification on a monitor is really not very meaningful. As a concept it is pushed by vendors who want to quote magnification numbers that are the next best thing to fraudulent. It is not really used in any other context than marketing.
Optical magnification is a good baseline bit of information but field of view (how wide the captured field in your image is) is the metric that ultimately matters. After all a 10x objective used directly on a 1" c mount camera, a m4/3 camera and an aps-c camera each give very different images, and that's before you get into different magnification factors on your adapters and dofferent field numbers on objectives. If you know the field of view you can do an apples-to-apples comparison across images no matter what setup was used.
Optical magnification is a good baseline bit of information but field of view (how wide the captured field in your image is) is the metric that ultimately matters. After all a 10x objective used directly on a 1" c mount camera, a m4/3 camera and an aps-c camera each give very different images, and that's before you get into different magnification factors on your adapters and dofferent field numbers on objectives. If you know the field of view you can do an apples-to-apples comparison across images no matter what setup was used.
Re: Calculating monitor magnification- no intermediate lens
Nice. This is helpful information. I just assumed that the magnification number on the monitor would be useful in some way... especially when compared to total magnification of eyepieces and lens together. Good to know that it isn't something to pay attention to. Cheers!Scarodactyl wrote: ↑Thu Dec 29, 2022 2:13 amThat's because calculating magnification on a monitor is really not very meaningful. As a concept it is pushed by vendors who want to quote magnification numbers that are the next best thing to fraudulent. It is not really used in any other context than marketing.
Re: Calculating monitor magnification- no intermediate lens
.
If you want to ‘get your head around’ this … it’s easier to think in terms of angles of view instead of linear or area magnifications.
[Hint] … we don’t usually print a photo at 20” x 16” and then view it from a foot away.
MichaelG.
.
P.S. __ This, from Leica, is probably the most rational explanation [justification?] of the enormous results of your calculation: https://www.leica-microsystems.com/scie ... ally-mean/
… and here is something more concise, from Zeiss: https://www.microbehunter.com/microscop ... 25&t=14884
If you want to ‘get your head around’ this … it’s easier to think in terms of angles of view instead of linear or area magnifications.
[Hint] … we don’t usually print a photo at 20” x 16” and then view it from a foot away.
MichaelG.
.
P.S. __ This, from Leica, is probably the most rational explanation [justification?] of the enormous results of your calculation: https://www.leica-microsystems.com/scie ... ally-mean/
… and here is something more concise, from Zeiss: https://www.microbehunter.com/microscop ... 25&t=14884
Last edited by MichaelG. on Thu Dec 29, 2022 9:09 am, edited 2 times in total.
Too many 'projects'
Re: Calculating monitor magnification- no intermediate lens
Why not using a object-micrometer ?
The distance is known and you can measure the distance on the monitor.
The distance is known and you can measure the distance on the monitor.
Re: Calculating monitor magnification- no intermediate lens
Awesome! Those articles definitely helped!!MichaelG. wrote: ↑Thu Dec 29, 2022 8:38 am.
If you want to ‘get your head around’ this … it’s easier to think in terms of angles of view instead of linear or area magnifications.
[Hint] … we don’t usually print a photo at 20” x 16” and then view it from a foot away.
MichaelG.
.
P.S. __ This, from Leica, is probably the most rational explanation [justification?] of the enormous results of your calculation: https://www.leica-microsystems.com/scie ... ally-mean/
… and here is something more concise, from Zeiss: https://www.microbehunter.com/microscop ... 25&t=14884
Re: Calculating monitor magnification- no intermediate lens
I have a stage micrometer. I know how to get the FOV. After reading the article in the link of the original post, I was just wondering about total magnification on a computer screen and what it means.