Look up the PMS7003, I think I got it for $40 bucks on aliexpress and it's used in many air filters to monitor PM2.5 and PM10 etc sized particles. Easily run by a raspi and i output to a regular segmented display for my particle counts averaged every 5 minutes to see the california fires and how quickly my air filter could clear the room. For reference the winix 545 ($110 from costco iirc) on full blast got me down to about 0 particles in 15 minutes.
edit: oh and regarding fan noise, the PMS7003 has a tiny centrifugal fan in it but I can barely hear it with my ear on top of it. The winix air filter on full blast though... crazy loud compared to the other low/med/high settings it's kind of hilarious how big of a jump it is in fan speed
Sorry I didn't explain too well. That link is to an online demo server of the Kolibri app that has that channel imported.
You can get the same channel locally (localhost; for offline use) using the following steps:
1. Download Kolibri https://learningequality.org/download/ , 2. Install and start, 3. Go to Device > Content > IMPORT and choose the channel called "Khan Academy - Standardized Test Preparation" from the list, 4. wait for import process to finish, then you're done.
I posted the same info in another comment on this thread of this story so I didn't want to repeat here. See that for more info.
Let me start first. I wish there is a free open source note taking software that will allow me to easily insert inline images (copied from a clipboard). AFAIK, the only software that has this feature is Zim Wiki. But its interface is very primitive in a mac.
Online tutorials and Youtube videos were some help, but really it just takes practice. Muscle memory is key. I used two tools repeatedly, the clone tool and healing brush, then magnified the work area to zoom in on details. I think the patience I learned has transferred to other non-Photoshop tasks. Others here have commented on similar results.
