These LED panel give a nice soft light source for photography, saves electricity, robust and won't heat much.
I am not a professional photographer, just enthusiast that sometimes has professional justify to build silly stuff like this.
I decide to do two big ones and one smaller that i would add battery later for outside shooting.
Step 1: Planning and Ingredients
So now I know that my bigger panels would take 99 leds and smaller would have 81 and you can left only 36 on by switch, if you want to increase battery life.
So where to house them. First looked into buying some aluminium briefcases for it, but then remembered that I had previously bought some aluminium school cooking containers from 70s for possible iPad and laptop bag, but now that project would wait and these cases would get a new purpose. I think these where perfect for the task. bigger panels where built on one container lid as one panl and botom
I wanted to able to dim this led although I know that it might be a possible problem and introduce flickering specially in low power, but then I decided that I will be mostly run them full power and I just went a head with a simple premade led dimmer.
Some switches i tried to find ones with bit of a retro style.
I think aesthetics are important I can find myself enjoy something I have built more if it also looks good.
List of parts
3x Led dimmer 12/24 volt 8 amp
price of one 9£
3x power supply 5 amp
price of one 5£
5M 300-SMD 5730 LED strip rope light white
3x power switch
price of one 2£
3x power plug
price of one 2£
some electric wire
3x photography light stand
price of one 9£
Step 2: Led Placement
Remember to buy more than you need.
So after getting rid of non working ones I cutter the strip in smaller right length strips. And placed them pre planned position. And started to cut out wires and place switches on right places to get an idea if all would fit well.
I laid few layers of tape under led strips for isolation and then temporarely taped them in place.
clear tape works here fine as it does not block reflections from the aluminium container.
Step 3: Dimmer
note: Remember these kind of dimmers are very basic and works with Pulse Width Modulation principle. witch means that when led is dimmed it actually cuts the current for really short periods rapidly. You can't see this by eye, but when used for video or photography camera can pick up these cuts and it looks like a flickering or produce artefacts when shooting video.
This comes more problem when lights are dimmed a lot and high speeds for shutter time is used. Problem goes away when full power is used.
Step 4: Holes
note: buy round DC plug so you can mount it easy just by drilling one hole. My power supply had DC 2.5mm male plug so i bought corresponding 2.5mm female plug.
Step 5: Testing Electronics
note: be careful that no electric connectors touch metal or short circuit when you test. duhh :)
Step 6: Taping to Final Position
note. I used aluminium tape to maximise reflecting surface on the panel.
Step 7: All Done
This is a first version of these lights. I am really happy about the results, but here are few things i might re-think or do differently for next version.
Mounting. well this didn't go as planned I first bought flashgun mounts that seemed like perfect place to start, but company that sold them could not get them delivered and returned my money. I was running out of time to enter 4th Epilog Challenge so I went a head and made them from mounts that I already owned ment for surveillance cameras.
Not ideal,flimsy and i don't recommend.
warmer leds or even adjustable color temperature
i would place every panel in own case though having two panels in one case lid and bottom takes less space. its not handy when you just need one also gives more freedom in control, switch and power plug placement. By placing them only one end can make more robust design.
Light intensity not measured with professional equipment just simple sensor.
next to panel 5700 lux
1m 250 lux
2m 100 lux
next to panel 2700 lux
1m 170 lux
2m 80 lux
Thanks to my girlfriend for being the best assistant ever.
Thanks to everybody for reading :)