פרידמן ניר
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1. בעזרת כרטיס לבן. 2. בעזרת כרטיס אפור כמו בפילם. יתרונות וחסרונות (עדיין אני לא סגור על אופן הביצוע עם האפור) : Gray cards can be used for white balance. You can even buy "warm cards" that have a slightly bluish tint to cause the resulting color temperature to be warmer. Most gray cards today are manufactured to exacting standards of neutrality. Under average lighting conditions there is no difference between setting the white balance with the gray card or the white card. The difference shows up in extremely bright light or extremely dim light. The benefit of setting white balance using a gray card instead of a white card is that in very bright light, especially if you haven't set the exposure first (ND filter and iris), it is possible to overexpose some colors of light in the mix and not others, resulting in an incorrect white balance. In other words, some colors might be so blown out that they wouldn't register properly relative to the colors that are less bright. And setting white balance with a gray card should prevent this problem because it reduces the intensity of all colors evenly. The benefit of setting white balance with a white card instead of a gray card is that in very dim light, as you mentioned, you can still get a reading. Whereas the gray card might not reflect enough light to get an accurate white balance. Some colors may fall below detection when their intensity is reduced by the gray, resulting in an incorrect white balance. I haven't had the opportunity to use an ExpoDisc. The ExpoDisc is a prismatic filter that gathers light from 180 degrees in front of the camera and has a translucent white back. It provides an even colorcast of all available light. Under most conditions, this average is close to 18% gray. The obvious benefit of the ExpoDisc is that you don't have to carry a gray card around and don't have to position the gray card. You just set the white balance through the ExpoDisc and then take the filter off to shoot. I am wondering how the ExpoDisc performs in very bright light, very dim light, and under situations of uneven lighting. And does it come in a 72mm size?
1. בעזרת כרטיס לבן. 2. בעזרת כרטיס אפור כמו בפילם. יתרונות וחסרונות (עדיין אני לא סגור על אופן הביצוע עם האפור) : Gray cards can be used for white balance. You can even buy "warm cards" that have a slightly bluish tint to cause the resulting color temperature to be warmer. Most gray cards today are manufactured to exacting standards of neutrality. Under average lighting conditions there is no difference between setting the white balance with the gray card or the white card. The difference shows up in extremely bright light or extremely dim light. The benefit of setting white balance using a gray card instead of a white card is that in very bright light, especially if you haven't set the exposure first (ND filter and iris), it is possible to overexpose some colors of light in the mix and not others, resulting in an incorrect white balance. In other words, some colors might be so blown out that they wouldn't register properly relative to the colors that are less bright. And setting white balance with a gray card should prevent this problem because it reduces the intensity of all colors evenly. The benefit of setting white balance with a white card instead of a gray card is that in very dim light, as you mentioned, you can still get a reading. Whereas the gray card might not reflect enough light to get an accurate white balance. Some colors may fall below detection when their intensity is reduced by the gray, resulting in an incorrect white balance. I haven't had the opportunity to use an ExpoDisc. The ExpoDisc is a prismatic filter that gathers light from 180 degrees in front of the camera and has a translucent white back. It provides an even colorcast of all available light. Under most conditions, this average is close to 18% gray. The obvious benefit of the ExpoDisc is that you don't have to carry a gray card around and don't have to position the gray card. You just set the white balance through the ExpoDisc and then take the filter off to shoot. I am wondering how the ExpoDisc performs in very bright light, very dim light, and under situations of uneven lighting. And does it come in a 72mm size?