Introduction
A cyclorama is something I've always wanted. Until building my current studio I've never had an adequate place for one. So, like most of us, I've had to use seamless background paper-which I loathe. I've never seen instructions for building one, so I was forced to invent the technique demonstrated here. So far, everything seems to be holding up just fine. Be forewarned, this project is a lot of work, and the finished cyc weighs a lot-like maybe a ton for every 16' or so. If your floors and walls are not real sturdy, don't try this.
Decide just how big you want to make your cyc. This will be determined by available space, general size of subject matter, and the lenses you normally use. It helps to play around a bit with the area you will be using with a mockup and test subject, just to define the rough dimensions. Mine ended up being 12' high, 12' deep, and 16' across the face. I can cover this area with a 135mm lens at the length of my studio-which is about 40'. Your mileage may vary.
Materials
An exact materials list is impossible because it will depend on the finished dimensions of your cyclorama. However, the cyclorama will require: 3/4" plywood, 5/8" plywood, 1X2 furring strips, 1/2" Dens-Shield tile backers, 1/4" luan plywood, diamond mesh lathing, tile backer screws, nails of several sizes, construction adhesive-both caulking-gun tubes and gallon-size, 36" wide rolls of drywall reinforcing/repair fabric, a prodigious quantity of thin-set mortar (the kind used to set ceramic wall tile), metal or plastic drywall corners, and drywall compound. All of the necessary materials are usually to be found at home building centers.
Steps(see cross-section drawing)
- 1) If you are doing new construction, face the wall behind the cyc with 5/8" CDX plywood, held in place with construction adhesive and 1-1/4" drywall screws.
- 2) Strip the floor back to subfloor. I glued and screwed the 5/8" plywood
to the existing subfloor with trowelled construction adhesive and 2" drywall
screws.
On a concrete floor, I'd probably lay down pressure-treated 2X4 sleepers in construction adhesive beds and cover these with two layers of plywood with staggered joints, secured with trowelled construction adhesive and screws.
- 3) The curve of the cyc is supported by a plywood rib every 12". These are cut from 3/4" CDX plywood with a saber saw. A piece of 1X2 furring strip is glued and nailed to both straight edges of the ribs. (See drawing for details) These are glued and nailed to the junction of the floor and wall, vertically, every 12".
- 4) Attach Dens -Shield to wall and floor with a bed of thin-set mortar applied with a 1/4" notched trowel and tile backer screws. Allow to set for several days.
- 5) Glue and nail 1/4" plywood over ribs. This goes best with two people to help, as the plywood is quite springy. For a radius under about 30", the plywood will have to be cut into 2-3" strips.
- 6) The diamond mesh lathing is stapled onto the plywood over the area of the curve.
- 7) Cover the floor and walls with self-stick fiberglass plaster patching cloth. This is usually available in 36" X 75' rolls. It will have to be cut into shorter pieces, about 6 feet long in order to make handling easier. Pieces should overlap about 2" all around. Work carefully when applying so that there are no wrinkles.
- 8) Cover the entire cyc with a layer of thinset mortar. I find it easiest to control the thickness by first applying it with a 1/4" notched trowel, then smoothing it out with a finishing trowel. Be certain to force the thinset through the fiberglass and the diamond mesh on the curved area. Allow several days to set up.
- 9) Locate thin spots, rough areas and places that are rippled, and apply another thinner layer of mortar over these with the finishing trowel. Allow several more days to dry.
- 10) Nail down metal drywall edging to forward edge of the cyc. It may be necessary to trim one side of the edging to get it to lie flat on the upper surface.
- 11) Cover the entire cyc with a thin layer of drywall compound. When this has set, repeat applications until ridges and rough spots are all concealed. This will probably take 4 to 5 sessions to accomplish with progressively less time between them as the coats get thinner.
- 12) Prime the cyc with latex or oil-base drywall primer. I opted for two coats, though one would probably have been enough.
- 13) After priming, you may find a few places that need additional drywall compound. Touch these up and spot prime them again.
- 14) Final painting is a matter of personal choice. The cyc will be repainted many times throughout the course of its life. Generally, it will be a neutral color; white, gray, and sometimes black, though the first color we painted ours was for greenscreen video.
All images and text Copyright Dale Austin, 1962-2008
