Magnification in trinocular scope canera

[PhilW]

Hi All - I am a new user of an OMAX trinocular scope with an attached USB camera (no lens). It appears to see about half of the image. When I observe a 0.01 mm scale I see an image on the camera that is presumably just coming from the objective and hence is not magnified by the eyepiece - it is certainly magnified less than my eye sees? So, if I use say a 40X objective and a 10X eyepiece, my eye sees 400X, but the camera sees roughly 80X - is that correct? Does that mean that in order to record what my eye sees here I would have to use a 200X objective?

Also, I the camera image has say 100 pixels in the 0.01 mm, then the pixels represent 0.1 microns or 100 nm which is way below the visible light wavelength lower limit of about 400 nm. So I assume that having about more then 25 pixels to cover 0.01 mm is a waste of effort? Or am I missing something.

Thanks for your advice in advance!

[Scarodactyl]

Whwn you look through an eyepiece there are two lenses involved. The eyepiece which enlarges the image, and then your eye lens which reduces it and focuses it on your retina. The camera as you have it set up has no enlarging eyepiece nor a reducing lens. It is just getting the image directly on its sensor. The image is at least 18mm wide, but the camera sensor is smaller than that, probably much smaller. So what you get is a cropped image, simulating higher magnification. This is why reducing optics are often used, to gather more of that 18mmish image and smush it down to all fit onto your sensor

[PhilW]

Thanks for that! I suppose it would be possible to rig up an eyepiece in the trinocular tube followed by a reducing lens and an external camera, but I like the convenience of the camera I have. Too bad that what you see (in the eyepiece) is not what you get on the monitor screen in terms of magnification.

[Scarodactyl]

You don't need a full eyepiece+reducing lens setup for thay. Omax sells a standard 0.5x adapter for that (also available from amscope and any other number of sellers).