That is a Geller magnification standard with 50 micron lines and spaces.
The photo was taken with a tripod and is not out of focus, it's just at the limit of resolution.
The dinolite may have slightly better resolution, but the horrible led ring light is not suitable for the reflective metal surface.
It's also important to understand that this is the long working distance version, which gives greater depth of field at the expense of resolution.
Neither of these is in the ballpark of a proper microscope, now looking at the 2-micron lines and spaces region that is not even visible with the dinolite:
Here are images taken with a Zeiss Axioskop 2 and Luminera Infinity 1 camera with the 10x,20x,50x objectives.
This is a 20 year old microscope, and they are available used for a few thousand, although not with desirable objective lenses.
If you use a DSLR as the image sensor, you don't use a camera lens, you use an adapter that mounts instead of the lens and probably a c-mount adapter on the other end to attach to the microscope. You want to use the entire sensor, not focus the image onto a small part of it.
There are many types and configurations of microscopes and you really need to match that to what you are doing. For example, I always use a stereo zoom to look at knife bevels because I need the long working distance and depth of field that allows me to hold the blade and move it around.
For a flat sample, nothing beats the Axioskop with sub-1mm working distance. At the same time, I can still resolve those 2um lines and spaces by eye in the stereo zoom at 15x mag with it's much greater depth of field.
Microscopes are all about trading off between resolution, contrast, depth of field, field of view.
