On Mon, 14 Apr 2008 01:56:21 GMT, "Dudley Hanks"
<hanks.dudley@[EMAIL PROTECTED]
> wrote:
>
>"Paul Furman" <paul-@[EMAIL PROTECTED]
> wrote in message
>news:oSxMj.3509$vF.2071@[EMAIL PROTECTED]
>> tony cooper wrote:
>>
>>>>>>>> skippy-007@[EMAIL PROTECTED]
quotes...
>>>>>>>>> The camera plane is a horizontal line that runs
>>>>>>>>> directly across the camera position as it relates to the positon
of
>>>>>>>>> the
>>>>>>>>> subject.
>>>
>>> In the sentence quoted, it's perfectly clear
>>> that the plane is being extended in the form of a line.
>>
>> It is unclear without knowing if we are looking at a side view or top
>> view. The sentence only describes a line not a plane. The only plane
that
>> makes sense would be the film plane or sensor which is perpendicular to
>> the line connecting the camera & subject. Or maybe it's the plane that
>> meets the horizon? No way to know.
>>
>> This next part seems unrelated but suggests it's a discussion of the
line
>> connecting the camera & subject:
>>
>> >>>>>>> The subject is at the center of a circle and the camera
>> >>>>>>> is at the outside edge of the circle so we are able to move
>> >>>>>>> lights around an invisible circle at different degrees
>
>The way I read it, the OP is looking at a plane -- similar to the film
>plane -- which extends around the subject in a circle.
I don't think so. The plane is perpendicular to the axis of the
camera lens.
> If one were to place
>lights, either flash or floodlights, on that plane, one could maintain a
>given lighting ratio while shifting the lights around the subject.
The lights would be placed in an arc with the center point of the arc
being where the plane intersects with the camera lens axis.
I don't know whether or not that is a valid technique of lighting. It
seems to be something the OP has read, but there's not enough quoted
to take a guess about the validity of it.
When doing macro shooting straight at the subject horizontally, I do
position the lights in a rough arc around the axis of the camera lens,
but I certainly don't try to calculate how exactly they are placed.
In most of the macro work that I do, I shoot straight down on the
subject using a tripod. The lights are positioned equidistant from
the focal plane (because both the camera's position and the light
positions are fixed), but my lights are in a full circle and not an
arc.
> One
>could then vary the effect without altering the exposure as long as the
>subject to lights / camera remains constant.
>
>This could be useful if one wanted to quickly change from a side lit shot
to
>a more frontal exposure. One would merely move the lights but not have
to
>alter the exposure settings.
>
>I've seen this discussed in a few books I've read on the subject of
studio
>lighting, but there is usually a cautionary note that, as one shifts the
>lights, new highlights can pop up and throw off the exposure setting --
>effectively defeating the careful planning and meticulous work. Of
course,
>eventually, one would gain enough experience to predict this anomaly, and
it
>should prove to be a good way to organize a portrait studio where one
shoots
>more than one style of portrait.
>
>Take Care,
>Dudley
>
>
>
>
--
Tony Cooper - Orlando, Florida
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