Doc-Pi
Re: Doc-Pi
Nice one! Great to see it progressing. I haven't even had a chance to progress my projects for next RoboFaire as have been off sick last week and this week has been mission impossible - "Cleanup the geek area" as Courts coming home on the 10thand I need some space lol
BLOG: https://my.makeraddiction.com/
Thingiverse: https://www.thingiverse.com/seaton/
Github: https://github.com/madeinoz67
Thingiverse: https://www.thingiverse.com/seaton/
Github: https://github.com/madeinoz67
Re: Doc-Pi
Well Doc-Pi has been busy scanning in piles of document. One issue I have with it is that the photo colour varies quite a lot due to the RPi Cameras Auto White Balance (AWB) trying to figure out the best balance.
This evening I sat down and did a bit of Internet research and found this basic script: http://raspberrypi.stackexchange.com/questions/22975/custom-white-balancing-with-picamera
As I use the python based picamera module, here are the relevant lines of code:
With my LED flood lights turned on and with a blank sheet of Reflex white paper in, running it gave me two different values to try:
1) Rg = 1.8, Bg = 1.3
2) Rg = 1.9, Bg = 1.4
Now these are pretty close, yet there was a slight blue or orange tint between the two photos. Mind you I haven't tested my LCD monitor, so maybe its all perhaps just a poke in the dark. Maybe my brain will take it all in differently tomorrow morning?
Here is a sample photo:
and just to highlight some other issues, here is the same photo, with the Contrast, Gamma and Saturation all stretched horrendously:
Hmm, there are some issues here:
1) reflection of the overhead camera X shaped gantry (and camera cable). Could be fixed with the installation of a black paper dome lodged under the gantry and a hole cut out for the camera. If nothing else, I could at least print the gantry out in a matt black.
2) the glass lid handle is visible at the front. I could design and print a new one that curves away from the glass plate.
3) even with two bright 15W LEDs running the full length of the A4 sized platen, the brightness varies a lot. I will need to play around with this some more. I might be able to fix some of it in software, otherwise, maybe place some diffusers over the LEDs.
4) there is quite a range of colours on what is meant to be a white sheet of paper.
5) there is some lens barrel distortion going on. I knew that would happen, however it's less than I thought it might be. I could fix it with a post processing script.
Really though, I am just happy that the major colour variation issue is at least fixed to one pattern, and it's not changing photo to photo.
This evening I sat down and did a bit of Internet research and found this basic script: http://raspberrypi.stackexchange.com/questions/22975/custom-white-balancing-with-picamera
As I use the python based picamera module, here are the relevant lines of code:
Code: Select all
rg = 1.9 # set to match my
bg = 1.4 # LED floodlights
camera = picamera.PiCamera()
camera.led = False
camera.resolution = (2592, 1944)
camera.awb_mode = 'off' # has to be off before you can manually override the Red/Blue gain
camera.awb_gains = (rg, bg)
camera.capture(filename)
With my LED flood lights turned on and with a blank sheet of Reflex white paper in, running it gave me two different values to try:
1) Rg = 1.8, Bg = 1.3
2) Rg = 1.9, Bg = 1.4
Now these are pretty close, yet there was a slight blue or orange tint between the two photos. Mind you I haven't tested my LCD monitor, so maybe its all perhaps just a poke in the dark. Maybe my brain will take it all in differently tomorrow morning?
Here is a sample photo:
and just to highlight some other issues, here is the same photo, with the Contrast, Gamma and Saturation all stretched horrendously:
Hmm, there are some issues here:
1) reflection of the overhead camera X shaped gantry (and camera cable). Could be fixed with the installation of a black paper dome lodged under the gantry and a hole cut out for the camera. If nothing else, I could at least print the gantry out in a matt black.
2) the glass lid handle is visible at the front. I could design and print a new one that curves away from the glass plate.
3) even with two bright 15W LEDs running the full length of the A4 sized platen, the brightness varies a lot. I will need to play around with this some more. I might be able to fix some of it in software, otherwise, maybe place some diffusers over the LEDs.
4) there is quite a range of colours on what is meant to be a white sheet of paper.
5) there is some lens barrel distortion going on. I knew that would happen, however it's less than I thought it might be. I could fix it with a post processing script.
Really though, I am just happy that the major colour variation issue is at least fixed to one pattern, and it's not changing photo to photo.
Re: Doc-Pi
Well today I got fed up with the official 7" RPi Display being propped up and the electronics board just lying around, so I designed up a set of height adjustable legs for the display and a RPi Hat adaptor plate so I could mount the electronics board onto the back of the RPi/display. Both worked out really well:
I also quickly designed up and printed out some M2.5 x 16mm PLA standoffs, for the adaptor plate:
Now I just have to wait for the next Aliexpress bolt shipment to arrive, so I can bolt it all together. Note: to mount a RPi Display to a printed stand, you will need four M3 x 6mm bolts. Aliexpress sells assorted M2 & M3 bolt kits for around US$6, and they include 30 x M3 6mm bolts.
I was surprised how clean and exact they printed out. I don't think I will need to purchase any other stand off again.
I also quickly designed up and printed out some M2.5 x 16mm PLA standoffs, for the adaptor plate:
Now I just have to wait for the next Aliexpress bolt shipment to arrive, so I can bolt it all together. Note: to mount a RPi Display to a printed stand, you will need four M3 x 6mm bolts. Aliexpress sells assorted M2 & M3 bolt kits for around US$6, and they include 30 x M3 6mm bolts.
I was surprised how clean and exact they printed out. I don't think I will need to purchase any other stand off again.
Re: Doc-Pi
Well, thanks to Stephen for the offer of four M2.5 x 25mm bolts. I have been able to assemble adaptor board on to the RPi Display:
and then mount the electronics board, to make a triple decker:
Final, it's all up and running with light blaring away in full glory:
Well, there's nothing left to do hardware wise, I suppose I am just going to knuckle down to work on the software side of things.
and then mount the electronics board, to make a triple decker:
Final, it's all up and running with light blaring away in full glory:
Well, there's nothing left to do hardware wise, I suppose I am just going to knuckle down to work on the software side of things.
Re: Doc-Pi
Very nice as usual Paul! Those prints are looking good
What are the brick regulators you are using? Isolated?
What are the brick regulators you are using? Isolated?
Re: Doc-Pi
Hi BeJay,
yes, the prints are near perfect. Very happy with the Felix printer.
I have listed the 5V switch regulators part number on the circuit diagram above. they are meant to be 90+% efficient. Maybe around $14 or so from Element14, and Adafruit sell them too. I keep a stock of them, as they are so handy.
yes, the prints are near perfect. Very happy with the Felix printer.
I have listed the 5V switch regulators part number on the circuit diagram above. they are meant to be 90+% efficient. Maybe around $14 or so from Element14, and Adafruit sell them too. I keep a stock of them, as they are so handy.