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QUESTION: Inexpensive _uniform_ backlight diffuser

 
 
BD
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      04-27-2006
Hey, all.

I recently stumbled on a site with some rather nice nude model pix; the
photographer accomplished a very interesting effect:

The subject was backlit with a very bright, uniform white panel. This
was the only lightsource in the image. This resulted in only an outline
of the subject being visible - all surfaces facing the camera were
almost completely dark.

He then (I assume) went around the edges of the subject in post, and
converted all that white backlight to black.

The result was a very compelling outline of the model. Nice effect.

I can see how I could accomplish a similar effect in post, but am not
sure what I could use for a lightsource to obtain the image in the
first place. At first glance, some kind of diffusion material of the
kind used to cover fluorescent ceiling lights makes sense; I'd make a
simple frame for it to keep it stable, and for additional diffusion I
could staple some kind of light white fabric overtop of the frame. I'd
then put a very bright lamp behind the panel, and there's my
lightsource.

Does that sound like a reasonably effective means of diffusing light
for an application such as this? Are there any other 'silver bullets'
for such a lighting requirement? Ideally inexpensive ones?

Thanks for all ideas!

BD

 
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ASAAR
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      04-28-2006
On 27 Apr 2006 13:06:15 -0700, BD wrote:

> The subject was backlit with a very bright, uniform white panel. This
> was the only lightsource in the image. This resulted in only an outline
> of the subject being visible - all surfaces facing the camera were
> almost completely dark.
>
> He then (I assume) went around the edges of the subject in post, and
> converted all that white backlight to black.


A bright, uniform white panel would be nice if you already have
one, but there's no need for uniformity. All you'd have to do to
accomplish the same effect would be to have the subject's background
lighting bright enough to saturate (burnout) the sensor's pixels.

> I can see how I could accomplish a similar effect in post, but am not
> sure what I could use for a lightsource to obtain the image in the
> first place. At first glance, some kind of diffusion material of the
> kind used to cover fluorescent ceiling lights makes sense; I'd make a
> simple frame for it to keep it stable, and for additional diffusion I
> could staple some kind of light white fabric overtop of the frame. I'd
> then put a very bright lamp behind the panel, and there's my
> lightsource.
>
> Does that sound like a reasonably effective means of diffusing light
> for an application such as this? Are there any other 'silver bullets'
> for such a lighting requirement? Ideally inexpensive ones?


It might be easier using multiple small lamps rather than one very
bright one. You might even see several hot spots that they'd create
in the fabric, but using an appropriate exposure, the background
would appear uniformly bright in the shot, which is similar to the
effect often seen in the blown out areas in snow scenes that are
exposed for the subject instead of the snow. But if a single bright
light is used and you didn't want to remove all but a sliver of the
background, with a carefully selected exposure, the brightest
background would immediately surround the subject, gradually
darkening in all directions away from the subject, aka an extreme
vignette, which might make for a nice cameo.

 
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tomm42
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      04-28-2006
Google "Lightforms" may have one big enough. Not cheap but a good bang
for the buck.

Tom

 
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BD
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      04-28-2006
>A bright, uniform white panel would be nice

Yes, I never considered putting an opaque panel behind the subject and
illuminating that instead. I will try that first.

 
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Randy Berbaum
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      04-28-2006
In rec.photo.digital BD <(E-Mail Removed)> wrote:
: Hey, all.

: I recently stumbled on a site with some rather nice nude model pix; the
: photographer accomplished a very interesting effect:

: The subject was backlit with a very bright, uniform white panel. This
: was the only lightsource in the image. This resulted in only an outline
: of the subject being visible - all surfaces facing the camera were
: almost completely dark.

: He then (I assume) went around the edges of the subject in post, and
: converted all that white backlight to black.

: The result was a very compelling outline of the model. Nice effect.

Just off the top of my head I have another way to get this effect (if I
understand the description correctly). Use a black background and a strong
flash behind the model aimed at the camera (with the model between the
camer and the flash). The light of the flash would illuminate the edges of
the model with everything else dark. Flesh and other thin parts (like
hair) would transmit the light to the front where the camera would "see"
it. One other effect that might be interresting is if the model is fresh
from a hot tub and the studio is relatively cool with a fairly high
humidity. This would not be tocause the model discomfort, but for the
skin to be giving off moisture. If the conditions are properly managed
(temp, humidity, etc) the skin would be giving off slight whisps of
"steam" that would be backlit and thus captured by the camera. You would
have to play with the various atmospheric conditions as I am not sure of
the particulars. I can say I have seen this effect many times when
spelunking (cave exploration). After physical activity, at a rest break
our bodys tend to "smoke" in ways that could be interresting with
backlighting.

Just some thoughts off the top of my head. I haven't tried any of them so
can't attest to their practicality.

Randy

==========
Randy Berbaum
Champaign, IL

 
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Gene Palmiter
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      04-28-2006
It would be nice to see a link to the site. But from what we know your
answer sounds right to me. Taking out a bright background might not be so
easy in post as it would blend with the lit outline of skin. If I had an
umbrella smaller than the model I might try to bounce it a bit. Your
"wetness" ideas have merit...a spray bottle of water might come in handy to
"sweat" the model.

--
Thanks,
Gene Palmiter
(visit my photo gallery at http://palmiter.dotphoto.com)
freebridge design group

"Randy Berbaum" <(E-Mail Removed)> wrote in message
news:e2s4m5$c6j$(E-Mail Removed)...
> In rec.photo.digital BD <(E-Mail Removed)> wrote:
> : Hey, all.
>
> : I recently stumbled on a site with some rather nice nude model pix; the
> : photographer accomplished a very interesting effect:
>
> : The subject was backlit with a very bright, uniform white panel. This
> : was the only lightsource in the image. This resulted in only an outline
> : of the subject being visible - all surfaces facing the camera were
> : almost completely dark.
>
> : He then (I assume) went around the edges of the subject in post, and
> : converted all that white backlight to black.
>
> : The result was a very compelling outline of the model. Nice effect.
>
> Just off the top of my head I have another way to get this effect (if I
> understand the description correctly). Use a black background and a strong
> flash behind the model aimed at the camera (with the model between the
> camer and the flash). The light of the flash would illuminate the edges of
> the model with everything else dark. Flesh and other thin parts (like
> hair) would transmit the light to the front where the camera would "see"
> it. One other effect that might be interresting is if the model is fresh
> from a hot tub and the studio is relatively cool with a fairly high
> humidity. This would not be tocause the model discomfort, but for the
> skin to be giving off moisture. If the conditions are properly managed
> (temp, humidity, etc) the skin would be giving off slight whisps of
> "steam" that would be backlit and thus captured by the camera. You would
> have to play with the various atmospheric conditions as I am not sure of
> the particulars. I can say I have seen this effect many times when
> spelunking (cave exploration). After physical activity, at a rest break
> our bodys tend to "smoke" in ways that could be interresting with
> backlighting.
>
> Just some thoughts off the top of my head. I haven't tried any of them so
> can't attest to their practicality.
>
> Randy
>
> ==========
> Randy Berbaum
> Champaign, IL
>



 
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Pat
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      04-28-2006
As you see, there are numerous ways to do something like this. Using a
bright white background is one way, but a few words of warning. If you
get it too bright, you risk having the light bend around your subject
and cause some distortion (like the sun at sunset distorts the
horizon). Also, glare can be an issue. I would bet illuminating the
feet would also be a bit of a trick. Not of it couldn't be overcome
with lots of good equipment and technique.

Here's are a few alternatives. Use a white background and reflected
light to siloette the model. It's cheaper and easier. Then, in
photoshop, take the contrast way up to create the effect. If you are
using film, make a high contract inter-negative and print from that --
same basic effect.

You could also use a black background, as mentioned, the shoot the
model. Either overexpose it or regular exposure and adjust the
contrast. Then convert the image to a negative image.

When I do similar things, I find that smoothing the final image give a
more eye-pleasing result.

 
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BD
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      04-28-2006
Just some thoughts off the top of my head.

Randy - Interesting ideas; the remote flash would work if I _had_ one.


In fact, I'm not sure how well that _would_ work. Part of the effect
here is that the larger surface area of the 'panel' lightsource means
that more of the edges are illuminated, adding some additional
dimension to the subject. I wish I'd flagged the site. Oh well.

At this point, I think that a piece of white foamcore, illuminated from
the front and sides, in an otherwise dark room, will be the best place
for me to start experimenting.

Thanks!!

 
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BD
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      04-28-2006
>It would be nice to see a link to the site.

I found the site.

http://www/lorekphoto.com
-portfolio link (right side of page)
-fine art

Many of the shots in the top few rows are illuminated from the back,
resulting in a nearly silhouette kind of effect.

I can now see the steps that were taken to go from that effect, to one
such as

http://www.lorekphoto.com/photo_gall...JQbGKPo#photos

This is what I am looking to emulate - on the cheap.

 
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dj_nme
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      04-28-2006
BD wrote:
>>It would be nice to see a link to the site.

>
>
> I found the site.
>
> http://www/lorekphoto.com
> -portfolio link (right side of page)
> -fine art
>
> Many of the shots in the top few rows are illuminated from the back,
> resulting in a nearly silhouette kind of effect.
>
> I can now see the steps that were taken to go from that effect, to one
> such as
>
> http://www.lorekphoto.com/photo_gall...JQbGKPo#photos
>
> This is what I am looking to emulate - on the cheap.
>


It looks like it was the model was lit from both sides from behind, the
left light-source seems to be a stop brighter than the right.
The defined shadows going from both the left and right across her back
would suggest this.
 
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