Swap fixed and infinity-corrected lenses?

[jamspanic]

Hi,

Given a microscope with an infinity-corrected objective that is setup to image small objects ~20 microns in diameter, what would happen to the image if I swapped the infinity-corrected for a 160mm fixed objective?

Thanks!

[MichaelG.]

Image quality is likely to be degraded
... particularly ‘curvature of field’

MichaelG.

[Scarodactyl]

You caan sometimes get away with it on low powered objectives, rarely even see an improvement with a tube lens. Not so on high powered objectives where specs are tighter.

[apochronaut]

It entirely depends on which infinity system and which 160mm system. The infinity space in infinity corrected systems is rather shallow, so by the time the convergent beam from a 160mm corrected objective hits the telan lens of many infinity systems, it might just be fairly harmonious with whatever corrections are applied by that lens; or not. Some examples of 160mm objectives working pretty well in certain infinity systems exist but I don't know of any the other way around, since they would want for convergence.