Relation of scope slider direction and achromatic FL

[Honi]

What is the relationship between the direction that you would want to move the miniscope slider in, and the focal length of the achromatic lens?  I.e., if you are consistently wanting to move the slider so far that it falls out (too far up), would you want a larger or smaller focal length of your achromatic lens?

[Daniel Aharoni]

Hi Honi,
Moving the focus slider up (away from the body of the scope) shifts the focal plane shallower in the brain. Using a shorter focal length Achromatic lens does the same thing. So if you find yourself needing to image less deep into the brain you can switch to a shorter focal length achromatic lens. Hope this answers your question.

[om7]

Hello anyone,

Would implanting the GRIN lens at a shallower depth achieve the same result as using a shorter focal length achromatic lens? (The result being minimizing the distance you have to slide the focus slide up.)

Thanks!