Photographing shiny, round, engraved object

<p>A friend of mine has asked me to photograph a shiny, round, engraved object. The object is a WWI shell casing engraved with the figure of a soldier. Here's a snapshot taken with a single large light source behind the camera and to the left:<br>

<img src="http://www.slayman.com/temp/shell.jpg" alt="" /><br>

There are several problems. For one, the surface of the shell is uneven, with some areas "matter" (the bottom half of the shell) and others more highly burnished (the soldier's chest). The latter areas, in particular, produce specular highlights that are a bit too bright for my taste. (Note: There is no possibility of altering the object itself. I have to alter the light.)<br>

Also, making sure as much of the engraving as possible is legible is problematic. To maximize the legibility of the engraving, I want to rake a bright light across the surface of it; but since it's on a round surface, that produces really ugly reflections. To minimize the reflections, don't point the light at the soldier; but then some other part of the shell is much brighter, and the whole thing looks downright peculiar.<br>

My lighting kit is minimal: a couple of decent flashes, improvised reflectors and diffusers, etc. The "large light source" used above was a workshop lamp pointed backwards at a reflector made from a piece of white foam core board.<br>

Any thoughts or suggestions would be very welcome.</p>

<p>If you want to rake the light along the surface, try raking from top to bottom and/or bottom to top. That way, you'll avoid the specular highlights along the sides of this cylindrical surface.<br /><br />The shell is more-or-less a cylindrical mirror. To light it evenly without hot spots, you'll need to wrap the light around it pretty much evenly. A light tent might do it, or a piece (or pieces) of white posterboard curved around the object, with your lights aimed to illuminate the posterboard.<br>

<br />These are just suggestions. You're going to have to play with this, but it sounds like it'll be a good learning experience and fun object to experiment with.</p>

<p>You could paint with light in a very dark room. That should average out the specular highlights and reflections. I've never done it, could be interesting to try though :)<br>

<br /> Good luck!</p>

<p>Just to add to Richard's excellent suggestions...<br>

If you're going to rake a light from one end to the other it will need to be as distant as practicable, to minimise the effect of light fall off over the length of the shell casing.</p>

<p>You''ll want to hang a large softbox right over your camera, with the diffuser face pointing down, paralell with the table your object is resting on. The top of the object should be closer to the edge of the box, but extending up into the darkness, out of the direct path of the light eminating from the softbox.<p><br /> The bottom of the object will receive increasingly more illumination as it nears the table as the light from the softbox gets stronger. This is called "feathering". The top of the object gets light from nearness to the source vertically, but less due being out of the columnated light. The bottom gets more from being in the light column, but less by virtue of greater distance from the source.<p><br /> You have to take measurements along the the height of your object with your flash meter and adjust the position of the softbox (tilt and height) until you find the right combination of height, tilt and distance from the object... or by checking each exposure in yourr editing software and then adjusting your light's position (height, tilt and distance).<p><br /> You may want to build this set at some distance from the background and light the background separately to distinguish it tonally from your object.<br /> And dude... that is NOT a shiny object... t</p>

<p>what is with this new html formatting? It's not an improvement... t</p>

<p>A Polarizer might do the trick. It will stop the light, but will sure cut the reflections. Try that out..<br>

Or...<br>

Merge two photographs by changing the light positions..</p>

<p>Although your subject is not a shiny one, due to it being metal I would recommend that you use as much diffused lighting as possible. This may mean having large pieces of tracing paper or similar material between the light source and the subject from different angles and perhaps one to seperate the back ground as well. Please take a look at the fountain pen shot in my folio, I did for a client using 2 flash units with very large diffusers between the subject and light source so as to give the impression that day light was used. Hope it may help.<br>

Artur</p>

<p>OK, here's what you need to know to do this right: <br /> Angle of incidence equals angle of reflection. <br /> It's the light ricochet rule. It means that not only the light's position relative to the object matters, but also the camera's position relative to it. <br /> And... <br /> A large light source is diffuse, a small source is specular. <br /> The light size rule... <br /> Bring these together in the digital age and you'll see your solution to your problem. <br /> Step 1: In a white walled room, place the shell on the shoot table ON A LAZY SUSAN. Make sure the shell is standing in the center of the lazy susan. Step 2: Light the room by bouncing off the walls. Step 3: Put the camera on a tripod, and get your exposure right so that in the areas where the reflection of the light isn't too strong, you have a clearly visible subject. Step 4: Make several exposures of the object, each at the same settings, while slightly rotating the shell on the lazy susan with each shot. As the shell rotates, the areas of specular reflection will change. Continue to do this until you have rotated the shell a full 360 degrees twice, shooting every few degrees. Step 5: Review your images, and select those that collectively show you everything you want to see, free of specular highlights. Then import into photoshop. In photoshop, create a master image containing all these images as layers. Line up the image so that from a stacked view, which you can use opacity for, the lines all line up. If that makes sense... Step 6: Add a layer mask (reveal all) to each layer, and paint it into a single image with no specular highlights. Then flatten. <br /> Voila! This should work, with some tweaks likely... And not only that, but with a good 3-d modelling program, you could probably create a 3D image, too.</p>

<p>Many thanks to all, after something of a delay, for your very helpful responses. I had hoped to be able to post a few results here, but in the end I didn't come up with anything I liked well enough to post. For the record, though, here's what I tried:<br>

--Feathering, with a white card under the shell: This produced very nice illumination of the shell itself, with the exception of some odd reflections of the card itself right around the base. (The object is shinier than it looks in the snapshot...) These I was able to control with a polarizer without dulling the whole thing too much. Where this didn't work so well was in highlighting the engravings, which were too low contrast really to show up. I experimented with lots of different angles here, but the only way I could get a satisfactory result was by bending the card up at an angle in front of the card. Trouble was that then the card was between the camera and the shell.<br>

--Building a large, semicircular diffuser to surround the shell on the front, with the shell placed on a black cloth. I used one light behind the diffuser, because all I had was one light. I think the technique of surrounding the shell with diffuse, even light would have worked very well, especially for a rollout where you wouldn't want any highlights, except that getting the light even with only one lamp was impossible. I really think it would have required a bank of small lamps spread out behind the diffuser to get it sufficiently even. (Also, the diffuser I made--from paper and a bunch of coathangers--didn't hang smoothly enough to avoid reflections in the brass.) So there were still hot spots on the shell in a way that I didn't like.<br>

So very interesting little project. I only wish I had more time and/or better equipment to get it really right. Complainign about not having the right equipment always strikes me as a bit lame, but in this case, given the result requested, I'm not sure there's any way around it. Many thanks again for everyone's help.</p>