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Studio Flash Basics
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PostPosted: Mon Mar 12, 2007 2:34 pm 
Studio Flash Basics

Good studio flash systems differ from on-camera flashes in many ways. In addition to providing considerably more flashpower, studio units are designed to be used with a wide variety of light shaping accessories such as umbrellas, softboxes, grid spot attachments, barndoors, beauty dishes and others. Each of these accessories provides a different quality of lighting, allowing the user to precisely compose light to suit his purpose.

Studio flash units are often used in multiples, with as many as four or more lights often used to obtain intricate combinations of light and shadow. The wide variety of setups involving studio lights demands that the user abandon Automatic Exposure Settings in the camera. Cameras must be set to Manual Mode with aperture and exposure time set manually. The power levels must be adjusted on each light separately in order to compose the scene, and a flashmeter is generally used to determine the appropriate camera lens aperture setting.


Modeling Lamps

In order for the photographer to be able to visualize what the scene is going to look like when the picture is taken, studio flash units contain Modeling Lamps. These are incandescent lamps of modest power that are placed in the studio flash in such a position as to mimic the light that will be emitted by the flash when the actual picture is taken.

There are certain considerations that must be met if the photographer is to be able to rely on his modeling lamps to provide a What-You-See-Is-What-You-Get (“WYSIWYG”) preview of the actual shots.

Some manufacturers ignore the requirements for truly accurate modeling lamps. This can result in exposures that don’t look like what the photographer expected and the requirement of many test shots and adjustments in order to achieve a certain lighting effect.

Accurate WYSIWYG modeling dictates the following:

1. Modeling lamps must accurately track flashpower adjustments in order to provide a constant relationship of modeling Lumens to flash Lumenseconds, with errors no greater than 1/10 to 2/10f at any power setting.

2. Modeling lamps must project similar beam patterns to the flash.

3. Modeling lamps, like the flash, should be immune to variations in power line voltage in order to maintain consistent accuracy regardless of fluctuating power lines. In this regard, all Paul C. Buff, Inc. studio flash systems employ high-precision voltage regulation of both modeling lamps and flash to provide consistent output at all power line voltages from 105 to 135 Vac.

We are not aware of any other manufacturer that provides any voltage-regulation of modeling lamps whatsoever and are aware of several whose modeling lamps fail to track flashpower, with errors of up to 3/4 f-stop or more – far too much error for effective visualization.


Power Range

Studio photography requires a wide and controllable range of flashpower in order to meet all lighting and aperture requirements demanded by a given session. Typical flashpower requirements can range from 5 or 10 Wattseconds (Ws) per unit up to 600 Ws or so. Outside the studio, when shooting in larger spaces, power requirements can be as high as 2400 Ws or more. Such power levels usually dictate the use of separate power packs and flash heads because of size and weight restrictions.

>> Click Here for more info on Monolights Vs. Power Packs

It is paramount that the studio flash units have a suitable base power range for the type of work anticipated, and be capable of a wide range of power adjustment with excellent accuracy, consistency and modeling lamp tracking. We recommend 160 Ws to 320 Ws units for small studios and 640 Ws units for larger studios. If you have too much power, you may not be able to dial the power down enough to get low aperture numbers with close light to subject distances.

All Paul C. Buff, Inc. studio flash units have a minimum basic adjustment range of 5 f-stops (from Full Power down to 1/32 power), and some models feature additional power range switching to extend the adjustment range to Full to 1/128 power or more.

NOTE: Some manufacturers use non-dictionary definitions and wrongly refer to a 1:32 adjustment range as a “6f range.” Correctly defined, Full to Half power is a 1f range of adjustment and Full to 1/32 power is a 5f range.


Flash Duration

Flash durations should be no slower than 1/800 second (T.5) for general studio use, but should be considerably faster than this if any sort of sports or dance or other photography involving moving subjects is anticipated.

>> Click Here for more detailed info on Flash Duration


Mounting Systems

Studio flash units should mount to standard studio light stands with a 5/8” mounting post and should accept standard umbrella shafts up to 3/8” diameter (9mm). Umbrellas should mount as close as possible to the lamp axis for symmetrical umbrella patterns, and umbrellas must swivel with the flash unit.

Studio flash units should be a capable of “bare-bulb” configuration and be fitted with a secure attachment mechanism that allows mounting a wide variety of accessories, including those made by third party suppliers. They should also employ a suitable swivel mechanism to allow the light and accessory to be secured at the desired angle. Paul C. Buff, Inc. lighting products use an accessory mounting system that is common to all of our products and to Balcar products. Nearly all third party suppliers provide accessories fitting the AB/WL/Zeus/Balcar standard.


Remote Control Capability

Using monolights that have no remote control capability can be rather challenging for most studio photographers. Lights are often mounted in inaccessible positions where adjusting the power levels and modeling lamps can be quite difficult. A good remote control system can allow the photographer to critically adjust all the lights right from the camera position, even while looking through the viewfinder. Please note that “Remote Trippers” only fire the lights and cannot adjust power levels.

Paul C. Buff, Inc. is an industry pioneer in the art of remote control systems. Essentially all products we have produced since 1986 employ a standardized remote control jack into which a variety of wired or wireless remote controls may be connected.

The LG4X Four-Channel Wired Remote can be plugged into a system of up to four lights and located as far as 500-feet away from the lights via inexpensive modular telephone cords. Thus configured, the user may adjust the power levels and modeling lamps of each light individually, as well as firing all the lights from a common wired or wireless camera sync connection.

The wireless CyberSync/CyberSync Plus System can control up to 256 light units, in banks of sixteen lights. It can digitally control the flash and model lamps of each light individually in precise 1/10 f-stop increments, as displayed on the single transmitter.

>> Click Here for more info on our LG4X Four-Channel Wired Remote Control
>> Click Here for more info on our CyberSync/CyberSync Plus Remote Control System


Slave Trippers

Studio lights normally contain flash-sensitive slave cells that can be set to automatically fire the unit when it “sees” the flash from another. This allows the user to sync only one light to the camera, allowing all other lights to then fire simultaneously without additional sync connections.


Fans

In order to allow for bright modeling lamps and all-day shooting with a variety of accessories, studio flash units should be provided with cooling fans to avoid overheating problems.


Warranty, Customer Service, Repair Service, Tech Help, Weight, Size, Durability...these, of course, are all very important considerations to any studio flash user. Considerations we well understand and endeavor to excel in implementing.


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