Speaking of a tank of gas, here's my latest darkroom:
I recently purchased an old 1969 class-C motorhome and converted it to a mobile wetplate collodion darkroom. Last weekend was its maiden voyage and it worked very well. It converts very quickly between a collodion darkroom, a totally dark space for using panchromatic materials, and back to unobstructed viewing conditions for driving around.
The windows are covered with curtain blackout material that I purchased at a local fabric store for about $3/yard. The material is fastened with 3/4" black self-adhesive hook-and-loop strips. This allows me to completely darken the interior in case I ever wish to load film holders or develop panchromatic materials. 3/16" thick transparent red acrylic sheet covers the window above the sink and the wide, large window at the rear. The rear sheet is wide enough to be flexible and I can bend it to fit a channel I made by attaching a sheet of wood to the right and left edges of the window frame. A series of turnbuttons hold the window in place and allow me to easily attach or remove it for driving or darkroom work.
Red acrylic sheet is also used to cover the ceiling vents when loading the plate holder or developing the plate. I can quickly slide the safelight windows over or off the openings to allow for ventilation within the vehicle. The red window directly adjacent to the sink also opens rapidly for ventilation. Blackout material shutters these openings as well. It is quite bright inside with the red windows in place.
I also used the blackout material to form a lightproof curtain at the bulkhead between the driving compartment and the box. It is stapled along one wall and attached using hook-and-loop to the ceiling and the wall partition that I've built out slightly from the cabin. This curtain blocks all the light flooding in from the passenger compartment and the cab-over sleeping area (which I have converted to storage for camera equipment, backgrounds and props. I'm still able to sleep in the area where the table converts to a bunk). I can quickly remove the bulkhead curtain for driving. The white color of the blackout fabric also helps to reflect the red light within the box and make for a brighter working space.
I've removed the oven and put in a countertop with a slot that holds the dropped silver-sensitizing tank. This is the same tank for up to 10" x 12" plates from my wheeled darkbox, which is also stored under the refrigerator. The refrigerator has been put into commission as a bulk chemical storage area.
The sink has been adapted to drain into cubitainers for collection of rinse water, spent developer, etc. The faucet is not used but there is plenty of room in this vehicle for storing a water supply. (For example, I keep 5-gallon jugs of water in the shower compartment where I also store tripods, etc.)
There is a temporary hanging curtain made from black plastic sheeting and stapled in place over the door area. I will replace this with Porter's darkroom cloth soon.
This vehicle has a lot of room for storage, sleeping, etc. Plenty of drawers and storage cabinets overhead in the box. The downside is that it really guzzles gas, so I won't be driving around in it casually. But, if you do see this plate on the road, you'll know it's me:
Joe