 BetterPhoto Member |
Studio Lighting I am photographing people with studio lights, with a white background. How do I make the background go completley white? I always seem to be able to see wrinkles on the backdrop or shadows from the wrinkles in the prints. I have been lighting with two lights on the background and one on the subject. Am I not moving the subject far enough away from the background, wrong exposure or lighting?
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Alan N. Marcus |
Hi Corin, First shadow free background is difficult. A black background is least likely to show shadows. White is the most difficult. You must pour on the background light. The idea is to over-expose the background. Severe overexposure forces the background to go white and detail like wrinkles vanish. If you were skilled with a light meter and you measured the background and set your aperture (and shutter for continuous lights), as the meter indicates, your background will reproduce middle gray regardless of its color. What I am trying to tell you is; you must light the background a minimum of three f/stops brighter than the subject, four would be better. You say you are using one “main” or “key” light. I suggest you place it high to simulate afternoon sun. Because white backgrounds lend themselves to a category we call “high key”, you are better off if the “main” is brought closer in to the camera, (almost by not quite frontal lighting). So maybe it would be best to place the main at the seven O’clock or four O’clock position (subject in center of clock, background at twelve O’clock, and camera at six O’clock). Now you second lamp should carry out the job of filling the shadows cast by the main. Set a lamp close to the camera at lens height. This will be the “fill”. This lamp is adjusted so the light arrives at the subject at 50% of the intensity of the “main”. Achieved either by power adjustment or setting the fill at a further distance than the main. If power is not adjustable and main and fill are equal fixtures. Measure main-to-subject distance and multiply by 1.4. This calculates the required fill-to-subject distance. Now the background light must be brighter as measured at the background. Again you can accomplish by distance. Place the background light hidden behind subject. Shine it upwards at the background. If equal to the main as to wattage, measure main-to-subject distance and multiply by 0.08. (Example main is 10 feet x 0.2 = 2 feet). Note: this may be impossible to achieve as the background likely will become unevenly illuminated plus with continuous lights the background might overheat. This all means, you need more fixtures so you can more evenly and brightly light the background. Maybe you should not attempt an even white background. You might want to practice your digital editing and enhancement skills. Alan Marcus (marginal technical advice otherwise known as gobbledygook)
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John H. Siskin |
Hi Corin, Most, maybe all, of the advertising shots you see with the white background are actually clipped from the original background. While this is time consuming it is often better than trying to do this in camera. The problem is that you need to reduce the light on the subject to the point where the background is overexposed throughout the shot. If you do that the edges of the background often get “burnt” from the over exposure behind them. So the problem is with exposure, but the acceptable range of exposure for the background is very thin. What is your goal for these images? Thanks, John Siskin
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Diane Dupuis |
Our white background has to be very well lit... I actually use two 500 watt garage "hot" lights to light it... Then my two continuous studio lights on my subect who is about 4-5 feet away. You have to set your exposure a little towards overexposure to get the white bright enough - and sometimes you have to finish it off (i.e. clean it up) in PS...
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Pete H |
Hello Corin, "I am photographing people with studio lights, with a white background. How do I make the background go completley white?" There is not quite enough information in your question. Are you shooting a group of people? One person full length? Head shot? A head shot is quite easy if you want to "blow out" the backdrop. In this scenario you are not covering much backdrop real estate; so it's pretty easy. One person shot full length is a little more technically challenging, as you must light from head to toe; it requires a white back drop AND a white material for them to stand on. A group of people requires a lot of (even diffusd) powerful light. With your two backdrop lights you can easily light a head shot or head & shoulders portrait with a pure white back drop. Full length one person? Doubtful unless you have very strong strobes and the ability to diffuse the light properly. Group? Forget it. Not with 2 strobes. John S advice is excellent. Blowing out a white back drop is quite easy in post processing and also very forgiving. (i.e) little chance of edge halo's. Black is do-able but MUCH more difficult unless you have a firm grasp on post processing techniques. Msking, clipping paths etc... Simply select the background, feather the selection to about (2) and raise the "levels" slider until it's pure white. The bonus to this method is you can now "Select inverse" and exposure & color adjust the subjects. If you need more help, feel free to email me for a better step by step proceedure. all the best, Pete
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Pete H |
Here's an example of the technique.
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