Derrel
Mr. Rain Cloud
- Joined
- Jul 23, 2009
- Messages
- 48,225
- Reaction score
- 18,941
- Location
- USA
- Website
- www.pbase.com
- Can others edit my Photos
- Photos OK to edit
As Village Idiot pointed out, fall-off is more about the distance between the light, and the subject, than it is about the light itself. HOWEVER, comparing different light modifiers, one against the other, and there are differences in how different lights cast their light. If you want a dark, shadowed side, you can pull the light in really close to the subject, and the "bright side" will be pretty bright, and the shadowed side will be quite dark, by comparison with the lightness of the light side of a subject. Using a large and effective reflector on the shadowed side allows the photographer to bounce light back, and into the shadows, to modify the ratio of dark-to-light. The key is using a reflector that is atually A) large enough to DO something and B)using a reflector that is EFFECTIVE.
Shoot-through umbrellas come in different sizes, and different fabrics, and they perform differently with different flash units fitted to them , as well as with "how" they are used. If you take a Nikon Sb 800 and choke it wayyyyyy up on the umbrella shaft and use a 45 inch shoot-through, only the CENTRAL part of the umbrella will be lighted, and the edges will have very,very rapid fall-off. If you back the umbrella off toward the end of the shaft and set the zoom head to 35mm, you can "fill" the umbrella, and get an entirely different effect, which is a broader "swath of light" that exits the umbrella, with a more-even amount of light between the center of the beam and the edges.
Shoot-through umbrellas vary, a LOT; On some, you'll get 45% of the light going through the umbrella, and 55% of the light reflecting backward, where it bounces all over the shooting area. This is not good,or bad, but just the way it is. A black-backed reflecting umbrella will almost always direct a higher amount of light toward the subject than a shoot-through umbrella will. The reflecting umbrella has a higher efficiency,and it sends the light basically, for the most part, in only one direction, and not all over the room.
The Lastolite Umbrella Box lights MORE like a softbox than a traditional umbrella does, because of the way it works. The flash is aimed into the umbrella, which has soft, solid white fabric inside, almost a plastic-like fabric, covered on the outside by a 100% light-proof black coating, also kind of "plastic-like", not just woven fabric, but a sort of "coated" white fabric and a "coated" black exterior. The light is scrambled inside the umbrella, and then goes through the white nylon front face. This design makes the "distance" around double, or more, than what one would get with a shoot-through. The Umbrella Box takes the scrambled, diffused light from the first bounce, and then diffuses it additionally when the light goes through the front cover: to me, this is called "double-diffusion". It is the same process as adding a diffuser to a light, and then firing it through a scrim--it makes the light even softer. The Lastolite Umbrella Box and the Photek Softlighter that Annie Liebovitz relies upon are almost the same thing in how they scramble the light, and then diffuse it AGAIN, through a front fabric, much the way a softbox fires through an internal diffusing baffle, and then through a front white nylon fabric.
There is a second type of umbrella, which Zack Arias shows in one of his tutorials: it is the kind sometimes called a "brolly box", and is typically nothing more than a shoot-through umbrella with a black backing...it gives an ENTIRELY DIFFERENT type of light because it works very differently. Take a look at Zack's illustrations here, showing a shoot-through umbrella, and a softbox: I've moved the blog > zackarias.com/blog » Shoot Through Umbrella vs. Softbox
One of the most-important differences between 1) a shoot-through umbrella and a softbox, or 2) a Lastolite Umbrella Box or a Photek Softlighter and 3) a softbox is the degree of specularity the lights have. Shoot-through umbrellas are often very brightly lit-up where the flash blast through the umbrella fabric, and they often impart a sickly, disgusting, cheesy look to human foreheads and faces...lots of specular "sheen and shine"...which can make pictures shown really small and on the web or in newspapers look visually "exciting". Lots of punch, and sharp delineation of facial features. Softboxes and the Lastolite and Photek double-diffusion umbrellas have less specularity on human skin, when used for higher-resolution portraiture that is going to be printed, bigger, and seen, bigger than on the web on on newsprint screened at under 120 dots per inch...
To me, the Lastolite Umbrella Box is the perfect umbrella for people...the "quality" of the light is different from either a shoot-through, or a reflecting umbrella. It is a double-diffusion, enclosed, rounded light. The Photek Sotlighter has even more ribs, and is even more-rounded. At "normal" studio distances, the 40 inch Lastolite Umbrella Box delivers a quality of light that I like. it is softer, with less specularity, and lower fall-off, than with a traditional reflecting umbrella. They cost almost $80 a pop. They are not $19 Chinese cheapies...
Shoot-through umbrellas come in different sizes, and different fabrics, and they perform differently with different flash units fitted to them , as well as with "how" they are used. If you take a Nikon Sb 800 and choke it wayyyyyy up on the umbrella shaft and use a 45 inch shoot-through, only the CENTRAL part of the umbrella will be lighted, and the edges will have very,very rapid fall-off. If you back the umbrella off toward the end of the shaft and set the zoom head to 35mm, you can "fill" the umbrella, and get an entirely different effect, which is a broader "swath of light" that exits the umbrella, with a more-even amount of light between the center of the beam and the edges.
Shoot-through umbrellas vary, a LOT; On some, you'll get 45% of the light going through the umbrella, and 55% of the light reflecting backward, where it bounces all over the shooting area. This is not good,or bad, but just the way it is. A black-backed reflecting umbrella will almost always direct a higher amount of light toward the subject than a shoot-through umbrella will. The reflecting umbrella has a higher efficiency,and it sends the light basically, for the most part, in only one direction, and not all over the room.
The Lastolite Umbrella Box lights MORE like a softbox than a traditional umbrella does, because of the way it works. The flash is aimed into the umbrella, which has soft, solid white fabric inside, almost a plastic-like fabric, covered on the outside by a 100% light-proof black coating, also kind of "plastic-like", not just woven fabric, but a sort of "coated" white fabric and a "coated" black exterior. The light is scrambled inside the umbrella, and then goes through the white nylon front face. This design makes the "distance" around double, or more, than what one would get with a shoot-through. The Umbrella Box takes the scrambled, diffused light from the first bounce, and then diffuses it additionally when the light goes through the front cover: to me, this is called "double-diffusion". It is the same process as adding a diffuser to a light, and then firing it through a scrim--it makes the light even softer. The Lastolite Umbrella Box and the Photek Softlighter that Annie Liebovitz relies upon are almost the same thing in how they scramble the light, and then diffuse it AGAIN, through a front fabric, much the way a softbox fires through an internal diffusing baffle, and then through a front white nylon fabric.
There is a second type of umbrella, which Zack Arias shows in one of his tutorials: it is the kind sometimes called a "brolly box", and is typically nothing more than a shoot-through umbrella with a black backing...it gives an ENTIRELY DIFFERENT type of light because it works very differently. Take a look at Zack's illustrations here, showing a shoot-through umbrella, and a softbox: I've moved the blog > zackarias.com/blog » Shoot Through Umbrella vs. Softbox
One of the most-important differences between 1) a shoot-through umbrella and a softbox, or 2) a Lastolite Umbrella Box or a Photek Softlighter and 3) a softbox is the degree of specularity the lights have. Shoot-through umbrellas are often very brightly lit-up where the flash blast through the umbrella fabric, and they often impart a sickly, disgusting, cheesy look to human foreheads and faces...lots of specular "sheen and shine"...which can make pictures shown really small and on the web or in newspapers look visually "exciting". Lots of punch, and sharp delineation of facial features. Softboxes and the Lastolite and Photek double-diffusion umbrellas have less specularity on human skin, when used for higher-resolution portraiture that is going to be printed, bigger, and seen, bigger than on the web on on newsprint screened at under 120 dots per inch...
To me, the Lastolite Umbrella Box is the perfect umbrella for people...the "quality" of the light is different from either a shoot-through, or a reflecting umbrella. It is a double-diffusion, enclosed, rounded light. The Photek Sotlighter has even more ribs, and is even more-rounded. At "normal" studio distances, the 40 inch Lastolite Umbrella Box delivers a quality of light that I like. it is softer, with less specularity, and lower fall-off, than with a traditional reflecting umbrella. They cost almost $80 a pop. They are not $19 Chinese cheapies...