There have been many discussions here on intonation - and there are many great YT tutorials that can help us focus on it.  It was thru the early Fiddlerman tutorials that I discovered the violin is nothing without the bow.  Seems like every day I find new reasons why the bow might be MORE important than the actual violin/viola/cello. 

When I feel my intonation off, I usually look to my left hand for how I'm placing my fingers.  When my 'tone' isn't good - that's when I usually look to my bowing and left hand finger pressure. 

🤔... can the bow effect intonation, too?   

YES! 

I was surprised by a few of the reasons why & how, in this video tutorial!  How to Ensure your Bow Arm doesn't RUIN your Intonation - Jonathan Taylor. 

There's a tip in this video I found VERY unusual, but interesting... wearing earplugs while practicing - helps to focus on intonation without hearing the clutter of overtones!  3 Ways to Improve Intonation on Violin - Luci (Doublestop Music).

One thing I found mentioned repeatedly... if you want good intonation, don't let a day go by without spending a few minutes with your fingers on the fingerboard.  Nomatter how much we've learned in the past, going days/weeks without any practice - is counterproductive.   

I haven't had the greatest year, myself... if you are injured, work long hours, tired, it's the Holidays, or travel without your fiddle - look into things you CAN practice, without an instrument (even learn new music)!  search how to practice without a violin (YT)