Thursday, December 15, 2016

Cheap lighting

I needed a better solution for how I was lighting my background while scanning but even the cheapest work lights I could find were over $20 each and would still need modifications to work for my needs, so I ended up just building two lights for about $20 total (not including bulbs) and some left over materials I already had that would hold 2 100watt CPF bulbs. This involves some electrical wiring so if you're not comfortable working with electricity this may not be for you or you should get someone to help you with the wiring section.

The most expensive part of the build was the socket and bulb splitter. The socket was about $6 and the splinter $3 so after tax it was just under $10, x2 brings the price to about $20

First part of the build was making the back of the light. It needed to be solid as the socket will mount to it along with the stand so I used a thin piece of scrap wood, I believe it was from the top of a wooden pallet. It's about 3-4" wide and 8-12" long.

Next is to build the hood. For this I used 1 sheet of foam core board for each light. Cardboard would work also but I had some extra foam core. You can make the cone any size/shape you like but the taller/wider you make the cone the more material you will need. Just make sure it's big enough to fit the bulbs.

Then it's just a matter of attaching the panels to the wood back. I stapled the bottom of the panels to the wood base and then used tape to attach the panels to each other at the top and middle.

Now for some kind of stand. I plan to have the lights sitting on the table next to the background paper so I just need a small stand. For this I used a wire hanger. Just cut the hook off, then cut the wire in  half (one for each light) and straighten each piece. Twist two rings in the wire so you can attach the wire to the wood back with some screws, and then bend the rest of the wire into the shape of a 7 under the light to create a foot for it to stand on.

Almost done, now to add some power. This is the part where if not done correctly you can hurt yourself later so be careful. Also this is based off North American electrical standards. I already had 1 old lamp cord and some wire and a plug but if you don't you can find some at a discount store usually for $1-2. You'll notice most 2 prong plugs have one prong larger than the other. This is the neutral side of the plug and needs to connect to the neutral screw of the socket, which will be silver in color. The other smaller prong is the hot side of the plug and needs to connect to the hot side of the socket, which is the brass color screw. The lamp cord will also have small ribs on one of the two wires to tell them apart. The ribbed wire is used as the neutral wire.

When attaching the wires make sure you wrap the wire around the screw in the directions the screw turned when tightening. This way it will continue to wrap itself around the screw at it tighten.

 Once you have the wires connected cover the screws with electrical tape. This way you can't accidentally touch the exposed wires, which would be bad. For the plug if you have a lamp cord with the plug attached your done, if you have the type shown above it's just a matter of inserting the wire in the correct direction and squeeze the prongs together so the teeth can pierce the wire covering and touch the wire inside. Make sure you thread the wire out the back of the light before either putting on the plug or attaching it to the socket.

Almost done, just re-attach the socket to the wooden back of the light. Then grab some tin foil and tap it onto the inner surface of the shade. Now you're ready to screw in the bulbs and start lighting up your subject.

If you like this post let me know in the comments or on twitter and if there's any other photogrammetry or photography elements you would like me to cover.

Wednesday, December 14, 2016

Busting Rocks

I started out as most do scanning rocks to test out different methods and techniques. Once I ended up with a somewhat decent set of scans for a given test, I move on to a new group testing out something new.

I'm up to to my 3rd set now, with one more to go. 1st set was just getting the process down, next set was testing different scanning practices, calibrating the image colour, and adding AO maps

3 set refined the capturing process and changes to my lighting table along with trying out substance designer to back normal and AO maps.

4th and I think final set of rocks I'll be testing the use of detail maps and see if I can get the texture map sizes down.

After I finish each set I uploaded them to the Unreal Marketplace. I don't expect much, but I figures any sales would help fund equipment or software upgrades. So if you need some unique high quality photo real rock assets for your UE4 game or architectural design project go take a look.