Mobius Rear-View Mirror Project

This project is going really well. This weekend was our first trip with the new 808#16 rear-view cam-mirror operational, and it did pretty well. I'm really pleased with the angle of view for normal driving use. It's not great for reversing at all, but I knew that would be the case. It shows a wide enough view to meet and overlap with the wing mirrors, but it's a long enough lens that you can see a decent way down the road behind you. I was a bit worried it might be susceptible to every bump, whereas wide-angle doesn't show that as much, but it's very steady.

I played about with the settings and found that some output sizes gave black areas down the sides, top and bottom or all round, but the obvious one PAL 4:3, if I remember correctly, filled the monitor with no distortion. I think I ended up with it mounted upside down, using the 180 degree rotation feature, and then flipped on the monitor, but I suspect this isn't necessary after all. I'll have to check, but I think the monitor flips horizontally as well as vertically, i.e. doing a mirror image directly. Several options seem to work: it's mainly a case of trying to get the writing readable on the OSD. Weird thing is I didn't notice I had it wrong at first, showing a normal camera view, until I got onto the motorway, and then it looked mental with cars coming up and undertaking me! I just pressed the view button on the monitor a couple of times and it was a mirror again.

Webbex gave very good service and the camera arrived very quickly. I had some early problems due to the USB cable that came with it not working, combined with my red-green colourblindness and the constricted position of the LEDs, which meant I thought I had it on charge and was waiting for it to finish when it wasn't, then decided it must have had long enough but I couldn't get it to work, format a card or save the syscfg file or something (I forget the details) - basically, no charge in it. Finally, getting my partner to tell me if there was a green light or not, I used another cable and it worked.

I soldered up the variable voltage regulator I got on ebay, the input side to the van's ignition supply via the plug and sockect hacked off the old reversing camera (probably the best bit of it). Actually, I tried it on a mains trainsformer first to check it worked. I soldered the output side (after tweaking the output to just over 5V) to the (hacked) USB cable part of the data cables. Then I just had to plug it into the existing AV feed. I've got it pointing out of the back caravan window at the moment, clipped to the frame with a bulldog clip, velcro and rubber bands, just until I'm confident it's the way to go - then I'll hack the new porthole for it with much better glass (those caravan windows are two layers of slightly warped plastic and pretty scratched, and when we put our bikes on the back, they obscure the view).

I bought one of the recommended cards but haven't got round to installing it, so it's just got a 2GB thing of dubious speed and quality. One error occurred on the way home, possibly after a quick start-up and stop again in a carpark - I noticed the camera didn't have time to boot up. Looking at the files, it seems to have reset the timestamp to 01/01/2012 (default), which caused a further issue later when the card was full and it tried to overwrite the oldest file, because it didn't. I got a "Recording error" message onscreen for the last few miles, and it didn't record those, presumably because all the files are younger than 2012! So perhaps I need to just remember not to start and stop quickly, or maybe I can fix it another way.

I tried changing the frame rate to its lowest, 5 fps, just to squeeze more of the drive home onto the small card, which gives a crazy speeded-up playback. I tweaked the exposure to be much lighter as well, because I did feel that the picture was slightly dark even with the monitor's brightness and contrast settings well up. I didn't know if it would come out on the AV feed as well as the recording, but I think it must do. It was a brighter day, but I had to turn the settings down on the monitor. Maybe the +1 lightness setting would do. I've not tried it in the dark yet, but certainly the clarity of it improved in the overcast early evening compared to bright daylight.
 
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