Dimmable LED Panel/softbox for Photography or Filming

by OffHoursEngineering in Craft > Photography

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Dimmable LED Panel/softbox for Photography or Filming

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As I started writing more and more and filming more and more it became apparent that I had a steep hill to climb in regards to quality.

In my mind there are 3 main factors that need to be looked at when it comes to making content pleasurable and easy to digest for the viewer.

  1. Subject
    -If your subject matter isn't interesting or presented in an interesting way you won't get noticed.
  2. Audio
    -Bad audio will make someone stop listening and change the channel faster than you can blink
  3. Image quality.
    -Dim or dark images with no vibrance or details will turn many people away almost as quickly as bad audio.

I can't really help you with number one, I am still learning myself, and it takes effort and practice more than anything

Number 2 is quite simple to fix. Buy a decent lapel mic for filming or a shotgun mic if you're vlogging and you are pretty much there.

This instructable will help you with number 2: Lighting

There are tons of tutorials for how to position light sources when filming or taking pictures and a quick search online can help you more than I can.

But I can show you how to build a decent led panel/softbox that is easy to position and gives the right amount of light to set the mood for your scene.

Supplies

What you will need in no particular order is the following:

  • 2 5m led strips
    • I went for the 6000k version because I mostly need the softbox to display colours correctly and show details. You can get 2700k version for more of a candle lit scene or 4000k version if you want it to be a mix of both.
  • A power supply for the led strips.
    • I bought the leds and the power brick as a package from EBAY
  • A picture frame thats 50mm deep and 600x400mm in size or lumber to build a frame.
    • I built a frame from scratch beacuse I had all of the material left over from a different project.
  • Optional: Wood glue if you're building a frame from scratch.
  • Fabric to use as a diffusor
    • I picked up a white sheet from Ikea called TAGGVALMO, it was the cheapest source of fabric I could find that was of a decent quality. If you want to you could go fancy here and get diffferent coloured fabrics for different effects.
  • Plywood or MDF sheet that is 400x600mm to use as backing.
  • Aluminium foil to use as a reflector
  • Spray adhesive or similar
    • This is used to attach the aluminium foil to the backing
  • A PWM dimmer circuit or the following components to to build one from scratch like I did.
    • 1-47uF Electrolytic capacitor

    • 1-100nF Ceramic capacitor

    • 1-10nF Ceramic capacitor

    • 1-DC Barrel jack

    • 1-10K Resistor

    • 1-FQP30N06L Power mosfet

    • 1-10K Potentiometer

    • 1-NE555P IC Chip

    • 2-1N4148 Diodes

    • 2-2P Screw terminals

    • 1-Switch

    • Perf or vero board

    • A small electronics box to mount it all in.

  • Optional: A multimeter to check for shortcircuits after soldering.

Build Video

How to build a led panel/softbox for photography or filming

Here we have the build video.

I would suggest that you start by watching it and then you can follow along step by step through the entire instructable.

You can of course skip it if you want, since all the steps should be outlined below, but there is always the possibility that something shows up on video more clearly and easier to understand than I can explain it in text,

Prepare the Frame

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If you choose to buy a finished frame you can move to step 2

If you are building a frame from scratch, start with cutting your lumber to size.

I used my table saw to rip the wide pieces I had down to 50 mm.

The lumber i used was 18 mm thick so to end up with a frame that's 600x400 mm i cut the 50 mm wide slats into the following lengths:

2 pcs of 600 mm

2 pcs of 364 mm

I pre-drilled all the joints to prevent splitting the wood. When that was done I used wood glue and regular wood screws to complete the joints as shown in the picture above.

While the glue is drying we move on to step three.

Prepare the Backside

I used my table saw to cut my left over piece of plywood into a rectangle that is 600x400mm.

If you don't have access to a table saw you can just as easy use a jigsaw, circular saw, or foxtail saw.

And if you have none of these things you can usually get help at the hardware store to cut sheets and lumber down to size.

When I had my sheet cut to size I used the spray adhesive to attach the aluminium foil reflector. Take care to make sure you get it as straght and wrinkle free as possible.

I was in a bit of a hurry and my foil ended up a bit crooked, luckily not by much so the frame will hide it in the end.

Attach the Led Strips

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You can do this 2 ways.

The first way is to keep the full length of the led strips and bend it over on itself back and forth in a zig-zag pattern so it covers the entire reflector. This will work just fine, and if you want simple and quick i recommend doing it this way.

I however thought this looked a bit untidy and decided to cut my led strips down to length of around 370 mm so they will fit inside the frame and lay completely flat against the reflector.

Which ever method you choose I recommend that you mark the foil reflector in even increments to get the light as uniform as possible in the end.

The led strips I got was marked in even increments for cutting so I ended up with 24 strips of 23 led diodes each.

Soldering

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If you choose to bend the led strip instead of cutting it you can skip to step 5.

If you cut the led strips you now have 24 short strips instead of two long.

To be able to power them all you need to create a positive and a negative power rail. This means connecting the strips in a parallel configuration with +12vdc on one end and Ground on the other.

You can see a simplified schematic and how it looks in real life above.

You will only need to create what is outside the rectangle in the schematic.

After all soldering is finished it is a good idea to use a multimeter to check for shortcircuits between the posittive rail, the negative rail, and the aluminium reflector.

PWM Dimmer

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This step is fully optional. If you don't want a dimmable softbox you can hook up the led panel that you made in the previous step to a constant power source and you are golden. Or if you got fancy and got an RGB led strip it probably came with a control box already.

If you are like me however and got a regular white one and want it dimmable you need to either hook up a dimmer you bought or build one and then hook it up.

This is not a tutorial about soldering or building circuits on veroboard so if you don't know how to do that you need to jump on YouTube or find another instructable that teaches that before you move on.

You can see the schematic of the the circuit I used in the picture above.

Install the switch, potentiometer, and barrel input on wires that are between 10 and 15 cm long. This is to ensure that you can place them in the frame without a problem.

Also make sure that the wires to the led strip are 15-20 cm to enable easy installation in the frame later on.

At its center is a NE555 timer. This is a multi purpose timer ic that was in almost every type of consumer electronic before microprocessors became more common.

In this configuration it functions as an astable multi vibrator.

What that means is that it does not have a stable mode. The output flip-flops (and yes, that is the technical term) between two values, high and low. The capacitors and the potentiometer decide how much time it spends in the off state and how much time it spend in the on state.

With other words how wide the on pulse is. And that gives us the Pulse Width Modulated (PWM) signal.

We use this circuit to turn the led on and off very rapidly and as long as this happens more than about 25 times per second it is not visible to the human eye. And unless you'e shooting some really high speed film it doesn't show up when filming either.

Frame Cut-outs

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If the glue has dried you can continue with the frame.

Measure your components and decide on a good layout for the controls. Drill and chisel holes of appropiate shape in the frame so the controls can be installed.

In the picture you can see how I placed my controls. I have a power input, an on/off switch and a potentiometer.

An option is also to mount them all on the outside of the softbox, in that case you only need a hole for the power cord to the led strip.

Light Diffuser

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Place the frame face down on the fabric you have chosen as a diffuser.

Cut it so that you can fold the edges of the fabric over the edge of the frame as shown in the right hand side of the first picture.

Fold the edge over the frame and staple it in place. Keep going back and forth across the frame so that the fabric is taut and wrinkle free when you are done.

Install the Dimmer in the Frame

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Install the small electronics box close to the power input to the led strips. I put it flush against the frame and used a small screw to hold it directly to the frame.

Install the controls and power input in the frame. You can see what mine looked like in the picture. I used some super glue to prevent the fabric from unraveling around the holes for the components.

Solder the output from the dimmer to the led panel.

Install the Backside

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Fasten the backside to the frame. I used 6 screws, one in each corner and one on each longside.

And just like that you are done.

The Finished Softbox

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Now you are ready to turn on and test out your finished softbox.

When I did this I noticed that the individual leds does show through the diffuser slightly but it does not seem to affect the function. I could go back and find a different diffuser but I'm still very happy with the performance so for now I am content to leave it as it is.

It is design in such a way that it is simple to come back later to swap out the fabric for something else if I want.

I have seen some other versions of home made softboxes that used Crêpe paper or baking paper as a diffuser.

That might very well make a better diffuser but since I will mostly use the box in my workshop I think the fabric is more rugged and will hold up better over time.

Comparison

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Here you can see the same cup lit by 2 diffrent light sources.

To the left is a led worklamp that gives 1800 lumens and to the right is the softbox.

The diffrence is slight at a first glance but when you take a closer look you start to notice some things.

  • You have a lot more glare from the white wall behind the cup in the first photo. This was even more noticeable in the videos I took of the build.
  • The shadows are a lot softer on the picture with SOFT-box, get it?
  • This cup might not be the best object to show this, but you have more percieved depth in the picture when it is lit by the softbox. .
  • Look around the top and bottom rim of the cup. You can see a lot more details along the perimiter since the light almost swoops around the object.

This might not seen like much but it gives a much more professional feel to the entire scene.

Having one softbox like this is great for taking clear photos for advertisements, ebay listings or the like.

For more serious filming or photgraphy you would probably want another one to be able to light an object from two directions.

Conclusion

When improving your photography or filming you should not begin with your camera, you should begin with your scene.

The right amount of light in the right colour temperature from the right angle can make all the difference. And starting with something like a homemade softbox Is in my mind one of the better ways to start experimenting.

It is always easier to go "Ugly Early" and have the ability to upgrade later on than to invest heavily upfront and still maybe not get the result or experience you want.

If you have any questions please comment down below or on YouTube. You can find both my website and YouTube address in my profile here on Instructables.

And if you liked it, please let me know.

Til next time.