I have been thru the ringer looking at ways to get good visuals on trichomes.
- I've had full on lab microscopes with camera attached.  Can be too magnified and too sensitive. And you need a desk setup etc.  Its a bit overkill.
 
- I've tried cheap handheld digital microscopes but they suck even though I read a lot of growers use them.
 
- I've tried jeweler loupes but you can't take a picture with them.
 
- I tried full DSLR macro shots but I could not get a good setup unless I spent $1K on a new lens for my Nikon.  I even tried reversing a my 50mm prime lens.
 
- I tried the phone clip on macro lens as well.  It was not bad but not great.  What is nice is instead of a small viewing space like a microscope eye piece you get the full size of your camera screen.
 
- Finally I got a phone clip on digital microscope.  This things works great.  Hand held so you can just leave your plant where it is and get a shot.  You can use the zoom on your phone to get even closer which is helpful.  The screen view is excellent assuming you have a good phone.  And you can just view it live or take a picture and view it later on a bigger screen.  And I find the magnification factor is ok.
 
This is the one I got.   I can't put a link in my post to Amazon for some reason.  Just do a search on this.
Alotm Universal Mini 60X Zoom Clip On Microscope Magnifier Micro Lens Adjustable Loupe with LED/UV Light for Mobile Cell Phones iPhone 7 6S Plus 6 SE Samsung Galaxy and other Smartphones