Comparison of a pi-camera and a 20x optical lens

Further comparison of different lenses

I have analysed a Motic LM Plan 20x/0.40 infinity lens, a Comar Optics 20x/0.40 lens, a Motic EC Plan 40x/0.65 infinity lens, a Motic LM Plan 50x/0.55 infinity lens and a Pi Camera to compare their image quality. The camera was calibrated and focused first manually then using the 3 levels of the autofocus function inbuilt in the Openflexure GUI. The photographs are of the following:

  • Tilia Stem
  • Cucurbita Stem
  • Rabbit Lymph Node

Tilia stem

Pi Camera

Comar Optics 20x/0.40 lens

Motic LM Plan 20x/0.40 infinity lens

Cucurbita stem

Pi Camera

Comar Optics 20x/0.40 lens

Motic LM Plan 20x/0.40 infinity lens

Rabbit Lymph node

Pi Camera

Comar Optics 20x/0.40 lens

Motic LM Plan 20x/0.40 infinity lens

Observations

The corners of the three images are better defined through the 20x lenses particulaly the Motic LM Plan 20x/0.40 infinity lens as all corners and the centre of the image are in focus. For the Pi Camera and Comar Optics 20x/0.40 lens, the cells in the top left and right corners and the black cell wall in the bottom left corner are slightly out of focus; these are much crisper when viewed using the Motic lens.

The images of the cucurbita stem when viewed through the Pi Camera and the 20x lenses are of similar definition and quality; the two 20x lenses are marginally crisper. You can also see that the magnification of the Motic LM Plan 20x/0.40 infinity lens is a bit greater than the other two lenses.

The definition of the rabbit lymph node through the 20x lenses is crisper than that through the Pi Camera and appears less hazy, particularly through the Comar Optics 20x/0.40 lens. As can be seen again, the magnification of the Motic lens is a bit greater than the other two lenses as the white pointed object in the bottom left corner and the black smear in the upper right corner are further apart than in the other two images.

Overall, the definition of the optics when viewed through the 20x lenses is crisper and is better defined than when using the Pi Camera, however the difference in definition is slight and the Pi Camera is good low cost option for observations.

The Motic and Comar Optics lenses both have their advantages and disadvantages; the Motic lens appears to have better definition at the corners of the frame, however its overall crispness is not as good as the Comar optics lens.

Comparison lenses with higher magnifications

There are two higher magnification lenses observed below, one is a Motic LM Plan 50x/0.55 infinity lens and the other a

Motic EC Plan 40x/0.65 infinity lens. For this comparison both lenses are used to observe the rabbit lymph node.

Motic EC Plan 40x/0.65 infinity lens

Motic LM Plan 50x/0.55 infinity lens

As can be seen above, the Motic LM Plan 50x/0.55 infinity lens has better definition than the Motic EC Plan 40x/0.65 infinity lens. It is easier to differentiate between the small cells dyed pink filling the majority of the frame with the LM Plan lens and the cellular definition can be seen more clearly in central pale pink region with this lens too. Counter to expectation, the magnifications of the two lenses appear similar when viewing this slide, this may be due to differences in the position of the slide.

@PiotrG

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