DIY Arduino Exposure Meter
Hey everyone, I wasn't sure if I should post this in here or the Exposure forum, but this seems more like the DIY type place.
So when I'm out taking photos and I need a meter, I usually walk around with an old GE PR-1, because it's a nice size and shape, and it works great. But it definitely has its limitations, especially with lower light levels. I've also got a Spectra IV for cine metering, but that's overkill to carry around in my pocket. I've also been getting into Arduinos a bit lately, and had purchased a cheap Pro Mini clone for a different project I had in mind. When I started playing with it, I began to wonder if I could make a small DIY light meter. I looked into the parts and it turned out the whole thing would be really inexpensive. So I gave it a shot!
It's called ƒLUX (for now), and it has a range of ISO settings from 1-6400, and shutter speeds from 1/3000 sec to 60 minutes, and cine speeds from 1-300fps (and of course I could always add more). It's still missing a couple of features that I want to add, and it needs to be assembled into a case, but it's close to done! Here's a video:
Comments and questions welcomed. Thanks!
Arudino Pro Mini clone (http://www.amazon.com/Estone-Version...no-Compatible/)
Adafruit TSL2561 Light Sensor (http://www.adafruit.com/products/439)
64x128 OLED Display (http://www.amazon.com/gp/product/B00...ilpage_o00_s00)
Rotary encoder with push button (http://www.amazon.com/gp/product/B00KHTLY7M)
This looks great! I am always interested to see more diy projects especially with arduino. I really need to learn Arduino, I bought the arts and board to build the enlarger timer here but never really took the time to learn it. So many great opportunities and options!
Good stuff. I love those OLED displays but I've not tried using one on arduino (just ARM). Where did you get the nice big font?
I think the best thing about the TSL2561 is that it has a separate IR sensor, so it might be (with some calibration and a short-pass filter) useful as a light-meter when shooting IR.
The light meter in my enlarger meter uses a TSL235R instead.
mexipike: let me know if you need any help with the build!
Thanks for the kind words!
An IR-only mode is definitely one of those missing features I want to add. I can access the IR sensor easily enough, but it's hard to know how the values coming off the sensor relate to an exposure, especially since I don't have an IR-sensitive meter to test it against. But it's definitely something I'm going to try to implement.
And about the font size, that's part of the gfx and oled libraries provided by Adafruit. It's just scaling the letters up by factors of 2 or 3, but yeah it's included in the library. Except for the ƒ/ symbol. That's a bitmap image.
Very cool -- it's always a pleasure to see there are still people making things!
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I like it. Thanks for sharing. Please keep us posted on this nifty project of yours. I'd love to make one for myself.
Edit: If possible, can you please do a spoon-feeding version of the video? Say, from start to finish, with a list of all the tools and other things you need to make one, how to load the software, how to calibrate, etc.
Last edited by Ashfaque; 05-07-2015 at 09:34 AM. Click to view previous post history.
Is the code hosted somewhere?
I haven't uploaded the code anywhere yet for a couple reasons. Mostly because I'm not done with it, but also because I'm not a programmer, so I feel like a lot of it is kind of hacky and that's sort of embarrassing? Especially the settings and menus and stuff. My wiring is probably iffy, too. I mean everything works, but I'm sure it's all done the wrong way. But yeah, once it's all finished I'll probably put it online somewhere. And I'll make a step by step build video, too.
I'm a programmer. Don't get self conscious about your code. Professionals often produce code that doesn't actually work, and yours does. There is a lot to be said for that.
Get it right in the camera, the first time... My flickr
I totally agree with mrred!
Get the code up, the best way to improve it is by feedback. I'm by no means a programmer but I still chuck my stuff up on github just in case someone wants to use and improve it.
Plus, I'm dying to make my own build of this!!