1. During dailies, was there sound playback? How was this achieved?
Pretty much as Walloon as described. They used what were/are known as Interlocked projectors. The film ran in ostensibly perfect synch.
**2. How long, on average, did it take to develop film for dailies?
** Dailies are turned around overnight. Technicolor dailies were indeed run just by that lab. The old classic Technicolor technology was sold decades ago, and while that lab still exists, it does not run Dye Transfer 3-strip Technicolor printing any more.
**3. How was sound recording done on a movie set? With a Nagra? What were common types of problems that could happen?
** True, the sound was run by hardwire to the Sound Building. Apparently most studios ran those cables underground, and unless you had mice gnawing your wires, you probably had relatively few issues. The problems are usually in connectors and wiring, not in mikes. I’d think that periodically, all of the jack panels in each Studio Building would have to be replaced, because of crackling and ticking heard from over-worn connectors. Virtually all sound connectors used today are gold-plated. It helps !
**4. Did the cameraman “check the gate” at the end of the roll to ensure that the film hadn’t been scratched?
**Walloon is ( rare as this is ) completely mistaken here. Since your questions refer to Hollywood movies, I can address the union and labor issues perhaps a bit more accurately then our resident Historian. Since well before Sound Films, it has been the job of the 1st Assistant Cameraman (sic, there are tons of 1st A.C.'s who are women ) to “Check the gate”. In doing so you are not in fact insuring that a scratch did not happen. What you are doing is looking for telltale signs that something MIGHT have happened. A good 1st A.C. can check the gate through the lens, since removing the lens will usually allow an errant hair or bit of emulsion build-up that is caught in the corner of the gate to disperse, leading to a false sense of security. If the gate is checked after the last take of the set-up, and BEFORE the Gate is opened or the lens is pulled, then you are examining the gate in the same condition as existed as the shot was being taken. In the case of a “rollout” ( where you are still shooting a shot as the film runs out through the camera body, to the take-up side of the magazine ), checking the gate is not worth the effort. The movement of the cut end of the film pulling through the gate will typically shove away a lot of hairs or debris. Scratches cannot be seen on shot negative, when you check the gate with the lens in place, you are looking at a frame of film that was exposed but not pulled through the bottom of the gate yet. I have known assistants who were worried about a camera body to check the gate through the lens, then hand-turn the movement of the body BACKWARDS a few frames. This indeed would allow the assistant to examine a frame or two, peering in with a maglite for scratched frame surface. As for my remark about attesting to the labor aspects of this question, it is not and has never been the Camera Operator’s job to check the gate. Not on a large Union shoot, anyway. Of course, documentary work and small two-person crews operate under a different dynamic.
**5. What type of mikes were used back then? Mostly booms? Were there lavaliers?
**Many studios used large Perambulator Booms, which were highly build rolling stands. The Boom Operator stood or sat on this device, and operated a most remarkably clever boom device. It would telescope straight out, and pivot around a central mount where the microphone was attached. I attempted ( lamely, I will admit ) to try to learn the basics of Boom Op work at ABC last winter. It’s unbelievably difficult stuff, and the really good boom ops can save a shot day after day after day. This device is still used daily on most if not all Soap Operas shot in New York City, by all three networks.
**6. Did movie sets have air-conditioning? Or did they become sweltering?
** They were and are unspeakably harsh places to work. The typical television studio is kept insanely cold. The coldest studio I have worked in is the Ed Sullivan Theatre, where they do the David Letterman Show. It is easily 50 degrees without the breeze. The air flow is incredible, and very brisque. There are several reasons for the attempts to keep the air cooled.
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Film cameras are not sensitive to heat the way television cameras are. Film stages may run hotter, but are still air conditioned for creature comfort over the long haul. In the case of television studios, it’s inescapably important to keep the camera bodies cooled down. ( E.N.G.-type news cameras that are hand-held are actually designed to work just fine in temperatures over 100 degrees farenheit. The Panasonic cameras used in the Atlanta Olympics were made to run so hot that they were scorching the ears of the camera ops who had them pressed to the sides of their heads hour in and hour out shooting the events.)
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Make-up runs more easily in heat. Unless you are shooting a scene that demands rivulets of sweat trickling down your starlets face, keep 'em cooler rather that not. 
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In 1949, the Studios ruled their roost most rigidly. People sweated and fainted. Doors might be opened or fans might be run, but the cost of air conditioning a film stage was prohibitive. I’ve never heard tell of a film stage being air conditioned in the old days. I’d love to be proven wrong on this one though, it is such intensely hot work.
**7. How long did dolly-tracks take to set up? Were they cumbersome?
** Dolly tracks were for many years wooden planks. The inflated wheels would ride over the planks, delivering some damned fine shots in the process. It’s tricky work. Eventually, steel tubed tracks were developed, that made use of high quality rubber and Urethane wheels. I’ve only once or twice laid planking for old style wooden tracks, but I have laid steel pipe dolly tracks hundreds of times. The tracks are welded, and made to fold up for ease of storage and transport. Then, they fall open to lay down in a more or less rectangle. They lock one section to the next, interfacing with pin and hole connections. The dolly tracks are just metal, with flat feet framing welded under the tubing. You have to use a variety of wooden blocks and wedges to insure that the track is TOTALLY levelled, and does not have any ticks or bumps. Nor can it squeal at all as the rubber tires move over the tracks. It is an art. There are people out there who own their own dolly track sections, so that they are insured of never having slightly dinged or bent tracks. A good set of tracks is a dream, a bad set can cost you hours on set. Depending on the job, those hours can add up to tens of thousands of dollars lost.
**8. What types of lenses were available?
**Lens development is pretty interesting stuff, I am a cameraman and Steadicam Operator and so the life and times of camera lenses is a much loved subject. For decades, lenses did not have any coatings on the front element and so there were flares and aberrations that were seen in shots where you could see a light bulb, the sun or other specular hightlights. The advent of Multi-Coated lenses ( to a large degree by Zeiss and Panavision companies ) allowed the lenses to render a more accurate and color-correct image. Interesting side note: When Janusz Kaminski was prepping the camera packages for " Saving Private Ryan", one of the creative choices made was to have the front-element coating stripped from the Panavision lenses used during the filming. This lowered the apparent contrast in the images photographed through those lenses, and to a degree produced the look you all saw. ( There was some filtration as well, I believe - as well as a specific lab processing ). The cameras in the older days ( pre 1940’s ) were not Reflexed. That is to say, you could not looK THROUGH the lens itself. You shot the movie using a Rack-Over Viewing system, that showed you what the lens would see, but you couldn’t see what the lens saw at all until the lab returned Dailies. The Arriflex Corporation won an Academy Award for designing the first spinning mirror reflex movie camera.
**1. Was power on a sound stage supplied from generators, or did the stage use power drawn from the power company?
**It varied. Believe it or not, different states allow different kinds of power use for movie work. Fire codes also control such things. In New York for example, you can tie into the main bars of a power panel in the basement of a house and literally tap into the power flowing into a building. It’s so-called “dirty power”. The power is not filtered for spikes, or controlled perfectly for 60 Hz cycling. Typically, one tries to use a Generator for power on location. This insures clean power, well regulated and free of spiking. I’ve been on a lot of sets where we tied in. It’s not a nightmare, but it can present complications. Studios could actually have a sub-station on the lot, for distribution and filtering.
**2. With regards to lights, what kind of failures could be expected? Were shorts or exploding light bulbs common-place?
** Until fairly recently, only tungsten lights were used to light sets. The advent of rigidly color-corrected fluorescent lamps in conjunction with solid-state ballast that are flicker-free has allowed lighter, COOLER (heat-wise) lamps to be used. Typically, these are Kino-Flo lights, or lights of that ilk. Previously, they were just huge bulbs ( called Lamps in the biz. A light is a fixture, a Lamp is the bulb.). Lamps could and did explode. Most Light makers such as the Mole-Richardson Company of Hollywood used wire safety meshes in the larger units, to protect against flying glass in the event of a blow-out. It does happen. Additionally, a light that used a focusing glass lens called a Fresnel would run the risk of having the Fresnel lens blow out. It was just a glass disk with carefully made concentric circles, it allowed the light to be focused to a degree. These could blow, and incredibly hot glass would fall. I’ve seen Fresnels blow out, and was burned on the arm once by a hot shard of glass. Many older Lights used what look a lot like huge light bulbs. Nowadays, most tungsten lights use Halogen-looking Lamps that are not as physically huge but throw much more light, wattage wise. They have to be handled with cotton gloves or a cloth, since any bit of finger grease will cause the halogen glass to explode in short order. In addition to old-style lamps, many older movie sets were lit with Carbon Arc lights. This was a most astounding method of using a controlled burn of carbon arc tips, which produced a blindingly harsh light. One could burn an arc light ( adjusting the amount of contact and distance between the tips was known as “Trimming an Arc Light”, and was a high art ). You would have some arc lights burning, and then shoot them through diffusion material to soften the harshness of you wished. The style known as Film Noir was known for using very harsh lights and high contrast images. The lights would be shot through layers of Spun Glass, if you wanted to soften or diffuse the light on the set. Nowadays, spun is synthetic but back in the day, it was literally spun glass sheets. I’ve held some, it’s just remarkable. They used to cut it into panels of the size needed at the moment by scoring the sheet on the floor using the teeth on the side of a quarter…
**3. How good was the sound-proofing on sets? Any ideas as to what kind of materials were used?
** It’s the ratio of how good your mikes are to how loud the set is. Sets are not built like houses, they are built to be made lovely and stripped down in VERY short order. The Making of The Wizard of Oz has a few interesting passages about just how fast one set was turned over into the next. It is still that way. Even sets on say, a soap operaa that may be seen by viewers for 20 years are just flats, clamped and/or nailed together and seamed over to look like rooms. Therefore, the sound-proofing on sets really comes from an amazing amount of self control. The walls and ceilings were covered with layers of asbestos and other thick cloth materials. This helped with sound bouncing up and around. Very few older sets were build up off the floor to avoid noises, since a hollow floor makes for loud footfalls. The Making of Star Trek talks in about how the sets were so noisy that one could hear people walking in other sets when one was being shot on, one could hear the toilet flush in the studio, etc. When on a studio floor, all movement stops cold during a take. It is a unique kind of tortue to be caught in a room during a Master Take. You cannot move at all, for minutes on end. When shooting on location, one is at the mercy of the world around you.
When in a studio, it is not unusual to hang large moving blankets ( called Sound Blankets, although they are identical to the moving blankets supplied when doing a house move ) up onto grip stands, and placed out of shot, to reduce echo and sound bounce. The sound proofing on sets from the outside world was pretty darned good, but back in the day, the motion picture cameras themselves were, for a long time, so large and heavy that they were enclosed in huge blimps, to muffle the sound of the movement and the motor. It was not until the late 1980’s that a man named Fritz Bauer in Austria invented a camera called the Moviecam Compact and eliminated the camera movement noise that had been the bane of all close-up quiet interior shots until that day. He did it in an incredibly clever way. He designed the camera’s movement to float in a moulded foam-rubber mount, so that the vibrations and sounds created by the movement that pulles the film through the camera body are almost all absorbed by this foam mount. Truly brilliant, and deserving of the Oscar he earned for it. Back then, the sounds made by the camera itself were usually the most complex sound problem on a studio set.
**4. What kind of meal breaks, turnaround times did the unions require? **NOT ENOUGH. 
Typically on a Union show, this is how it goes, and how it went- back to the origins of Unionized Studio Labor. You have an 8-hour guarantee. You’re paid for 8 hours, even if you work 1. After 8, you get 1.5 time for the first two hours of O.T., then for the subsequent 4 hours you get 2X time, then after that you are into Golden Time- 3X your normal hourly fee. In the film union I was in until very recently, ( the IATSE 600 Camera Guild ), you had to get a meal break after 6 hours. If you went 6 hours and 4 minutes, you hit Meal Penalty, calculated in 15 minute increments. Things tend to add up rather quickly. 
However, the Shop Steward on each set can go to the heads of the departments, and ask if all are willing to waive a meal penalty here and there. It is at the discretion of the crew to waive penalties, and is done so pretty rarely. One fights hard for one’s wages, one does not give away lightly. I was shooting an After School Special once with Anne Meara. We were working this long Steadicam shot across a soccer field with a lot of dialogue at the end of it, perhaps…a 3-4 minute take. We didn’t have a buy take, and lunch was coming. The light would have changed, the energy would be lost, and everything would be different if we stopped for lunch. All agreed to shoot for at least 15 min more, to get a buy take. We didn’t even go 30 minutes late, we got a few buy takes, and all were happy.
Turn-around time is regulated by the Union you are in. IATSE demands a 10 hour turnaround between the called Wrap Time and Call Time the next work day. That’s rough if you live 90 minutes away from location, or from the studio and want to shower when you get home… Regulations do vary from union to union, however.
Hope this helps you some !
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