Weird background question: glass brick wall

divamum

The building where I teach is built around a small courtyard garden; several of the walls are small glass bricks.

I was there the other night and it suddenly occurred to me it could be WAY cool to shoot a portrait against those glass bricks. However, while what's on the other side isn't clearly visible, it's not INvisible either.

If you backlight it (for instance, flash outside pointing inside, subject posed on the inside, back to the wall) will that help to keep the distracting elements down, or will you just get a hotspot? Or would it be better just to use flash inside and let light fall off take it down behind the subject? I haven't had a chance to try it out yet, and am just considering how I might be able to light it effectively.

Here's the type of thing I mean (from the inside looking out):

Tim Kamppinen

I think the best thing to do would be to just try everything and experiment. I've never done this so I can't be of more help than that, but one thing that I would try if I had the opportunity would be to fire a flash through the wall not as a background light but as a main light. I could make some really cool patterns of light on your subject depending on the distance from the light to the wall and from the wall to the subject. Try putting a 1/2 CTO gel on it to simulate sunset light as well... I'm guessing it would look really cool. Maybe gelled flash 10 ft from wall and subject against the opposite interior wall? Try it out and see what happens. I am looking forward to trying more stuff like this myself after reading Joe McNally's books. He's constantly firing his lights through windows, curtains, etc to make interesting patterns, and I love the results he gets.

divamum

Thanks, Tim - I hadn't actually thought of that... could be an interesting approach as well.

Anybody else on how to minimise the background? I'm dying to get out there and play, but I don't have a willing model to practice on out there - doing self-portraits while all my students stand pass by guffawing may not actually work....

Tim Kamppinen wrote:

I think the best thing to do would be to just try everything and experiment. I've never done this so I can't be of more help than that, but one thing that I would try if I had the opportunity would be to fire a flash through the wall not as a background light but as a main light. I could make some really cool patterns of light on your subject depending on the distance from the light to the wall and from the wall to the subject. Try putting a 1/2 CTO gel on it to simulate sunset light as well... I'm guessing it would look really cool. Maybe gelled flash 10 ft from wall and subject against the opposite interior wall? Try it out and see what happens. I am looking forward to trying more stuff like this myself after reading Joe McNally's books. He's constantly firing his lights through windows, curtains, etc to make interesting patterns, and I love the results he gets.

Tim Kamppinen

divamum wrote:

Anybody else on how to minimise the background? I'm dying to get out there and play, but I don't have a willing model to practice on out there - doing self-portraits while all my students stand pass by guffawing may not actually work....

Grab a student from study hall and tell them you'll give them extra credit if they stand in front a wall for half an hour...

Seriously though, I did this with one of the kids in my Geometry class when I was playing around with a DIY mini-softbox that I built... The best part is that they'll probably forget about it and you don't even have to give them the extra credit!

divamum

Tim Kamppinen wrote:

Grab a student from study hall and tell them you'll give them extra credit if they stand in front a wall for half an hour...

Seriously though, I did this with one of the kids in my Geometry class when I was playing around with a DIY mini-softbox that I built... The best part is that they'll probably forget about it and you don't even have to give them the extra credit!

Unfortunately, mine are college students so I can't persuade them quite so easily!!!

Tim Kamppinen

divamum wrote:

Unfortunately, mine are college students so I can't persuade them quite so easily!!!

Ahahaha... ok, next time you give an exam find the student with the worst grade in the class and then swoop in for the kill! "I can bump this up to a D if you assist me in a research project..." No problem!

Nikolai

I didn't have a glass brick wall, but I used ice blocks, which are similar in nature. As Tim suggested, highlighting it from the back and using it as a main light source is the primary idea.



If you crank up you light power, you can easily overpower the bg to at least 2-3 stops. And if your strobes are too weak simply choose a later time of day.

Also: shoot not into the wall, but almost parallel to it, this way you'll get even less ambient/bg...

HTH

Tim Kamppinen

Of course, it will work as a background too. I searched the strobist pool on flickr and found these:

http://www.flickr.com/photos/mizomi/3113193268/

http://www.flickr.com/photos/sidsiva/2374109645/

In both of these shots the bricks have daylight coming through them and the flash had a CTO gel on it. With the camera on tungsten white balance, the strobe light looks neutral and the daylight on the glass looks blue.

Nikolai

Tim Kamppinen wrote:

Of course, it will work as a background too. I searched the strobist pool on flickr and found these:

http://www.flickr.com/photos/mizomi/3113193268/

http://www.flickr.com/photos/sidsiva/2374109645/

In both of these shots the bricks have daylight coming through them and the flash had a CTO gel on it. With the camera on tungsten white balance, the strobe light looks neutral and the daylight on the glass looks blue.

Nice effect, and easy to do, too:-) Thanks for sharing!

divamum

oooooo.... these are the kinds of things I need! I always forget to search the strobist site for specific shots :facepalm

I'm still more worried about killing the actual background details through the glass than the light per se (ie, if I put the subject outside in the atrium and shoot into the building, I don't want the Pepsi colors of teh vending machines to show!!), but from what you've posted above this *should* be able to work if I set it up right.

I'm all excited about this now! Maybe I'll just make a fool of myself and do self portraits next time I'm there anyway

Tim Kamppinen

divamum wrote:

I'm all excited about this now! Maybe I'll just make a fool of myself and do self portraits next time I'm there anyway

Well, I still like my extortion scheme, but hey why not, right? There's always a chance someone will get curious and stop to ask you about it, at which point you can rope them into being a model. Or just set up your gear and stand there with a cardboard sign that says "Free Portraits"...

imagesofhim

What a WONDERFUL playground! That's exactly what I would do----PLAY, PLAY, PLAY! Try everything... I agree with the Tim, the extortion, or exploitation of your students would be PRICELESS---to them as well as you!!!!

Oh, how fun! Please post when you get something!

Jealousy is bad... and this wall can make a woman jealous!! Seriously, how cool!

divamum

Coming back to this...

How do you gel for THREE light temperatures? There will be the outside light, the flash, and the inside light is fluorescent? I'd love to try the CTO gel + tungsten setting trick, but will the fluor. throw a spanner in the works?