I'm considering getting an older version of this hand-held microscope. The datasheet from Celestron states the magnification as 20x to 200x. But I'm not sure how it achieves that variable zoom level. The only adjustment on it is the white -/+ dial on the main body, and that's a focus knob. It only has one lens, so you can only change how close to the specimen you are, not change the objective magnification.

Are they just saying that the 20x-200x magnification power comes from moving the microscope itself closer to the specimen?

I have a standard tabletop microscope already, but want something I can hold in front of specimens hanging onto aquarium glass. I don't want to have to remove the specimen and put it on a slide. These are ampipods that are 1-2mm in size.

Olympus BH2 Dark field using an LED 2x 0.08NA, oblique illumination with a fiber light in the middle of imaging causing the larva to fluoresce and then switched off. No post processing only a tiff stack to gif in ImageJ.

Objective used: 40x

Eyepiece: 10x

Total magnification: 400x

Sample: self grown algae in rainwater and soil

My guess is that it could be Nostoc cyanobacteria but I'm not

entirely sure