« Having the latest gear is nice, but great photographers don't have to have it. Use dedicated LED light panels.> I'm sure that would fix your problem (no need a big one), try to begin with simple LED lamp (daylight or not, feel free to setting up a WB manually) I really appreciate any advice you can give. One idea I had is to increase the number light from 2 to 4 and hang them from the ceiling, but I am wordering if this is really the best way forward. I am not an expert, but I think the light needs to be more diffuse, it needs to come from all sides. How do I solve this? I do not really want to start on a lightbox, because it hampers my access to the objects. My problem is that the side camera experiences reflection and over-exposure from one of the lights. I have two Powershot G10 camera's tethered to Powershot Remote. I'll now have to try it to see what happens, otherwise I'll never know This technique is used when photographing art through glass to prevent all reflections, but it won't work on metal as far as I know. I've found the paragraph about cross polarisation, but it doesn't mention metallic surfaces. The technique is mentioned in Ansel Adams "The Negative", in the chapter on Artificial Light Photography. Do you have a link to any references where it's used? Reflection is enhanced in metals by suppression of wave propagation beyond their skin depths. I've seen the effect on clear plastic where it brings out the colours due to stresses in the material, but that's all. Interesting, I've never heard of that before. The metallic reflected light retains the polarisation due to the filter on the source. You missed the bit where both the light source and the camera lens has a polarising filter. Thousands of new, high-quality pictures added every day. Polarisers don't reduce reflections from metallic surfaces. Find Metal reflect stock images in HD and millions of other royalty-free stock photos, illustrations and vectors in the Shutterstock collection. Its easy to handle, you dont need to bake and it will reflect in real-time so you can animate the objects of the scene. For flat surfaces like mirrors you need to create a Light Probe > Reflection Plane. That would just reduce the total amount of light getting through. By default, Eevee will reflect the HDRI and the lights but it wont reflect the objects of your scene. Also it predicts the Fresnel equations which specify the reflection and transmission for different polarization (which cannot be derived with arguments involving only the refractive index).įor metals the explanation also holds, the wave impedance is ideally zero for metals so that there is only a reflected beam.įor a list of effects why the wave impedance is different for different materials see John Fistere's answer.You could use a polarizing foil on the lights and a polarizer filter on the lens. The fundamental principle predicts the amount of reflection as well as transmission and also the direction. Especially the Snell law with the refractive index. If you think about it you will notice that this is only possible with three beams and not two.įrom this fundamental principle (taking into account polarization of E and H) all other laws dealing with reflection follow. In a simplified view, the wave impedance of the reflected beam has a negative sign so that for the three beams (incoming beam, transmitted beam and reflected beam) the ratio of E and H field is the wave impedance of the relevant material and also E and H are continuous at the boundary. This is true only at the first sight and is the reason why there is a third beam. when a light beam hits a boundary where two materials with different wave impedance meet. If you think about the two requirements, you may think that this is contradictory and cannot be fulfilled simultaneously under all cases, e.g. This is a direct consequence from Maxwells Equations, the fundamental equations describing the propagation of light. cannot change their value discontinuously at material boundaries. The important thing to note is that the wave impedance is the fixed ratio of the electric and magnetic field amplitude of the light wave and that the electric field and magnetic field must be continuous, i.e. The most fundamental answer is that water reflects light because the wave impedance of water is different than the one of air and the electric and magnetic field must be continuous everywhere in space.
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