Lighting Help for Curved Iridescent Metallic Surface

[DanK]

Probably a long shot...but...

Might anyone have experience or be able to offer advice on a lighting setup for photographing a Curved Iridescent Metallic Surface...

The subject(s) in question are raku pottery pieces...(my other hobby) the glazes have a multi-colored copper metallic finish, and are also iridescent...

Prefer an idea with hot lights (no longer have strobes)...

I usually get one or the other - the metallic surface or the iridescense in an image....but rarely both...

Thanks,
Dan

[Jack Dahlgren]

Probably a long shot...but...

Might anyone have experience or be able to offer advice on a lighting setup for photographing a Curved Iridescent Metallic Surface...

The subject(s) in question are raku pottery pieces...(my other hobby) the glazes have a multi-colored copper metallic finish, and are also iridescent...

Prefer an idea with hot lights (no longer have strobes)...

I usually get one or the other - the metallic surface or the iridescense in an image....but rarely both...

Thanks,
Dan

I suggest using at least two or three lights. Maybe you can show iridescence on one side and the metallic aspect on the other. Pottery doesn't move much so you can use a tripod and even things like desk lamps - depending on the size - to get the look you want.

[B.S.Kumar]

How about setting up separate lights for the metallic surface and iridescence respectively, and making multiple exposures on the same piece of film? You'd need to experiment with balancing the amount of exposure for the two sets of lights. And of course, you need a darkened studio to minimize stray light.

Kumar

[cjbroadbent]

Ask someone who does cars. He will tell you that you cannot light a reflective surface directly - but you can light what gets reflected in the surface.
As for irridescence, as mentioned above by Kumar, you might do a second exposure with a single point source on the camera axis. You might even do two sheets of film and blend them on photoshop to the right balance.

[George Stewart]

Try Rosco polarizing filters over your lights - they come in 17x22 sheets, can be cut to size and should be mounted far enough from the heat to not melt. Then use a linear polarizer on the lens and adjust all the filters so that there are no hot spots. This is called cross polarization, and I have used it to successfully image many a reflective surface.

If you can see both surface-types simultaneously with the eyes, one should be able to capture it with a camera.

[rdenney]

Try Rosco polarizing filters over your lights - they come in 17x22 sheets, can be cut to size and should be mounted far enough from the heat to not melt. Then use a linear polarizer on the lens and adjust all the filters so that there are no hot spots. This is called cross polarization, and I have used it to successfully image many a reflective surface.

Now, that is slick. I suppose I have heard about this approach, but it didn't register.

Also, the idea to light the surfaces that will be reflected is a good one. I have photographed tubas at times, and these are not iridescent (except for one fiberglass sousaphone used in a Dixieland band that its owner had had painted by an auto-body shop). But they are highly polished and either lacquered or silver-plated. They are also large and their size prevents the sort of table-top control one would have with silver, dishes, and so on. The usual lighting for these is two large, flat shoot-through scrims, a white background lit to blow out, and the camera located in the darkness of a narrow gap between the scrims. The scrims would provide reflections on the major surfaces, but leave the rims dark, and the camera would be invisible. Not easy to photograph these. I've seen ebay photos of shiny tubas showing the owner behind the camera--in one case wearing no clothes. The curvature of the brass was not flattering to his figure.

Rick "who'll have to give that cross-polarization technique a try someday" Denney

[DanK]

Thanks everyone for the replies...

Doubted I'd see a single reply on this one...

Looks like the 'cross filter' technique may be a good bet...

I hadn't tried a polarizing filter, thinking it would cancel out the iridescent areas... even less so had I considered filtering the lights...

Looks like the gels are back-ordered, so it'll give me time to experiment more with the distances and sizes of the light sources...

Thanks again,
Dan

[John Ramsay]

Hi Dan...I`ve been shooting raku pottery for years. I started out using Ektachrome in a Mamiya 645 the mid 90s and have now gone totally digital. You must first and foremost think shape. One high flood shooting over the top just off center and a low bounce just off to the other side. I like a very light background, cream for white glazes and a white backdrop for copper and various colored pieces. I also set up smaller pieces right on the light table and use the table as a filtered foot light. Oh, I prefer tungsten lights and shot tungsten film most of the time and now just set the camera on tungsten. Photo floods are just too much and tend to dance on the glazes. If these pix are for advertising don`t over do it. You`ll be setting up expectations that can`t be met by the naked eye. Raku has subtle effects that can throw off the best lighting set ups, you need to be patient and flexible. I recommend you use a lot of digital images before you go to film. Remeber to take it easy with P.S. PM me if you`d like to know more and see a few samples....John

[lenser]

Dan,

If you can locate any of the lighting information by the late Dean Collins, you may find the ultimate info source. Dean was a brilliant commercial photographer and teacher and many of his disparate subjects included curved metal surfaces, such as jewelry, cars, motorcycles and other reflective curved surfaces such as wine bottles.

His highly inventive solutions were based on a deep understanding of light and how is displays and affects the subject.

Good luck.

Tim

[DanK]

Hi Dan...I`ve been shooting raku pottery for years. I started out using Ektachrome in a Mamiya 645 the mid 90s and have now gone totally digital. You must first and foremost think shape. One high flood shooting over the top just off center and a low bounce just off to the other side. I like a very light background, cream for white glazes and a white backdrop for copper and various colored pieces. I also set up smaller pieces right on the light table and use the table as a filtered foot light. Oh, I prefer tungsten lights and shot tungsten film most of the time and now just set the camera on tungsten. Photo floods are just too much and tend to dance on the glazes. If these pix are for advertising don`t over do it. You`ll be setting up expectations that can`t be met by the naked eye. Raku has subtle effects that can throw off the best lighting set ups, you need to be patient and flexible. I recommend you use a lot of digital images before you go to film. Remeber to take it easy with P.S. PM me if you`d like to know more and see a few samples....John

Thanks John,

Sure appreciate this info...

Dan