Hello everyone. Having not had access to the space in months has made me want to actually make better use of it than I have the past year. As it’s been sunny and at the best of times I’m slightly obsessed with photography I have been making cyanotypes. The problem there is with the sun as a light source it’s pretty uneven and calculating exposures is mostly squinting and sticking your tongue out at the right angle. Hopefully understandably that isn’t exactly great when you’re trying to make reproducible prints.
I have however found this UV exposure meter project and figured I’d have a go making it and modifying it to suit my needs.
One thing I would really like to change on this is have it run off either a standard little lithium battery pack or 18650 cells, rather than 9 volts. I don’t know if it’s better to run everything here at 3.3 or 5 volts, shifting between the two seems like an exercise in annoyance.
Being rather new to electronic projects any more complicated than making an LED flash I thought I’d turn to the experts for some advice in how to do this and where to look for parts. I will doubtless even with a guide mess something up and need some advice I’m sure.
My next step is to try and copy his design on a simulator of some kind to just get a better understanding of how it all works together. Currently looking at what there is out there for that.
- Arduino board - probably a micro or a nano? Can’t really tell what the difference is between them
- UV Sensor module - Seemingly all three I have found are listed as discontinued on various sites but are available in small quantities in a few places like ebay. Options are ML8511, Adafruit VEML6070 and Adafruit VEML6075 which seem to be able to run on 5v or 3.3v.
- OLED display - low power use and ideally either monochrome or red (so I could use it in a darkroom). This is 3.3v rather than 5v though, so maybe I need something different here?
- Some kind of battery. I do also have some spare 18650 cells that Howard kindly gave me, with a battery holder alongside the remains of a mini power bank that conveniently has a charger/discharge board. Not sure if that’s any use though
- Switches - hoping I can fish some spares out of the parts bins.
- Enclosure - Not sure how big this will be, but possibly something like this box as inelegant as it is, with suitable holes for everything drilled into it. Maybe a reason to learn how to 3D print too?
- some kind of voltage regulator for the battery to the power for everything?
- input panel - He uses a keypad which I’m not sure I like as an input device but I also can’t really think of a better way to do it
*A visible light sensor - ideally I’d like to be able to use this for UV and standard light measurements