Tuesday, August 14, 2007

Lighting 102: Umbrella Specular Portrait

So, did you catch the post yesterday when we talked about the umbrella-background-reflection thing? I hope so, because that is your assignment this week.

This one is sort of a cross between an exercise and an assignment, as it requires a specific technique. You'll be doing a photo of a person, using one soft light source (shoot-through or reflective umbrella, soft box, scrim, whatever) and angling it so it becomes a specular highlight in a darkish, semi-reflective background.

I gave you some ideas on where to find such a backdrop in the previous post (see link above) but be creative. And speaking of being creative, try to look beyond the mere technique and make a real photo of someone. Add some personal style, catch a nice moment -- do something to make this a photo, rather than just a lighting technique.

This photo, shot by DINFOS workshop student Jason Robertson, uses the dark headboard of a bed for the dark backdrop. And he caught a nice moment, too.

That last part is very important. Light is not enough. In fact, you might want to take a moment to read this post on the topic.

As for light positioning, Jason used a pretty scary-looking human boom for holding the umbrella.

This is a fun, easy, one-light technique that yields a very polished-looking photo if done right. Give it a whirl and see what you can come up with.

Your tags will be:

Strobist
Lighting102
Assignment
Umbrella
Specular

Add "final" as a tag to your best shot, and "setup" if you are including a pull-back shot for the benefit of other readers. Those setup pix are much appreciated, BTW.

You can see all turned in photos here, and just the final edits here.

The assignment is due at the end of the day on August 26th.

Discussion for the assignment is here


NEXT: Umbrella Specular Discussion.


__________

Brand new to Strobist? Start here | Or jump right to Lighting 101
Connect w/Strobist readers via: Words | Photos
Ping me on Twitter: @Strobist

3 Comments:

Blogger Daniel Cormier said...

I have to question whether or not the reflection in your example photo is really a specular reflection. Yes, it is a reflection of the light source. However, the word "specular" (when talking about optics) means "directed, as from a smooth, polished surface".

The surface reflecting the light in the example is fairly smooth, but certainly not polished. To me, the reflection looks diffuse. Since there's no detail in the reflection, one could produce similar results with a softbox, or even a conteniently placed window.

Compare the reflection on the headboard in the first sample to the reflection on glass of the the framed image on the wall in the second. To me, only the second is a specular reflection.

I have no problem with being told I'm wrong. I just want to make sure I have this all straight...

August 23, 2007 3:41 PM  
Anonymous Pat Turner said...

To a physicist, specular reflection occurs when a reflected light beam comes off the surface at the same angle as the incident beam, measured from the normal (perpendicular) direction. See the diagram at http://en.wikipedia.org/wiki/Specular

I think the confusion here is that the "bright spot" caused by the bounced strobe is seen at the *angle* where one would look for a specularly-reflected beam. But since the reflecting surface is somewhat rough, each point on the surface does not act as a "specular reflector" and thus the image becomes blurred (although the light still falls within the main flash "bright spot").

Is that helpful?

August 24, 2007 4:18 PM  
Blogger dawn said...

From what i read in "Light, Science & Magic" i would say that in this photograph we have:
- a light source which is diffused (because the light is passing through an umbrella);
- mainly a specular reflection (because the light is positioned within the family of angles and dark objects produce poor diffuse reflection). The specular highlight is not strong because the headboard surface is mat. A polished surface would produce a specular highlight better defined, just like the one from the second photograph, reflected by the framed image on the wall.

Still, a surface produce diffuse, direct and polarized reflection in varying amounts.

August 26, 2007 9:13 AM  

Post a Comment

<< Home