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Showing results for tags 'gel'.
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Predilux : iOS app for gaffers and DPs
Georges Harnack posted a topic in General DiscussionHi, We are two technicians working in the film industry in France (a grip guy and a gaffer) and we just discovered this very interesting forum. We particularly noticed that gaffers and cinematographers were asking questions about light output and what aperture is obtained at a certain distance. It happens that with the help of two IT engineers we developed an iOS app responding to this question about 2 years ago. First and for all, we’re not going to post messages everywhere on this forum to sell our app nor are we going to pollute your threads to gain in visibility. We just think some of you might be interested in what we created and since we’re a really small team working on off-time we can’t do any real advertising, so you probably wouldn’t know our app existed. Our app is called Predilux (for pre-diction and lux for light) and predicts the exposure as measured by a light meter, by choosing a light source and a distance. Or inversely predicts the distance to the light source by specifying the exposure. Predilux takes into account: Camera settings (FPS, ISO, Shutter angle) Source settings (Focalisation, Lenses, Grids, Dimmer, CCT, etc) Gels mounted on or close to the source (All ROSCO e-colour+ range) All results have been experimentally verified by us with a light meter in rental houses. For each source setting we made several measurements at different distances and this took a lot of time. So Predilux does not rely on constructor’s data, but on real data reflecting the state of the equipment as found in rental houses. Our data sometimes differs from the constructor’s data. Here is a quasi exhaustive list of the sources measured and included in the Predilux (12/2019) : Tungsten ARRI 150, 300 Plus, 1K Plus, 5K Fresnel, T10, T12, Rubylight (MFL lamps) Briese 77, 100, 140, 180 with lampes ranging from 650 W to 2K Mole Richardson Softlite 1K, MaxiBrut 16 (MFL lamps) Openfaces such as Redhead, Blonde, Desisti Renoir 5kW and LTM Cyclight 2K ETC Source 4, Dedolight, Zaplight, CMC 20K, etc. HMI ARRI AS 575, 1200, 4K, 6K, 12K, Arri M18, M40, M90, ArriMAX 12K & 18K K5600 JokerBug 200, 400, 800, Alpha 1600, 4K, 9K, 18K AFM 575, 1200, LTM Cinepar 2.5K Fluorescent KinoFlo 2ft, 4ft & 6ft LED ARRI S30, S60, S120, S360 KinoFlo Celeb 200, 250, 400, 450, 850 DMG SL1, SL1 mini, SL1 Switch, MaxiSwitch Mole Richardson Tweenie, Senior, Tener Aladdin Biflex 1x1, 1x2, Flexlite 1x4, 350 Dedolight bi90, Cineroid LMD400, Velvet V1 Balloon Airstar Gaffair 1200, Elipse 4000, PAD 9ft x 9ft, Tube 16K If any of the administrators of this forum wish to try out our app, we would be happy to give them one or several free life-time activation codes. For all the other users, our app is available on the Apple Store (). An Android release is planned. If you have questions or requests, don’t hesitate to contact us at this address firstname.lastname@example.org Thanks for reading this post and we hope you thought it was interesting, Georges Harnack for the Predilux Team
Wood Frames of ND Gel for Window in BG?
Rob Davis posted a topic in Grip & RiggingI work on an unscripted show where we primarily shoot exterior interviews but occasionally will move inside and use a window as our background when the weather is bad. I’d like to be able to ND the window to reduce the amount of light needed on talent and am thinking of having a couple of wood frames built out of 1x3 strips of lumber so we could quickly drop in different levels of ND. Being that the window is only a couple feet behind talent (out of focus but barely), is this a good approach or would we see lots of reflections, etc.? We don’t have time to apply the gel directly to the window as the light changes frequently, and don’t have the budget to get hard NDs. I think a large net would be too close and in-focus to disappear completely. We also can’t drop a polarizer for the camera to mitigate reflections because talent always wears sunglasses. The window is always shaded, however, so we’ve had no reflection issues with the glass itself.
Gel, Transmission, and Colour Temperature
Hirokazu Taka posted a topic in LightingHi, I've been conducting a little research about gel and I wasn't sure the relationship of transmission and stops. Say, a gel has transmission of 30%. Does that mean that the gel reduces the luminance by 70%? If so, is it in lux or lumen or stop? (I don't have a firm understanding of these units so I might be saying random things) Also, is it helpful to know the transmission vs. wavelength chart? I'd also like to know how the colour temperature of an original source affects the end result through gels. Is there a certain colour temperature that's most appropriate for gels? Or is it totally up to users? If you have your way of working with gels that'd be amazing to know as well. Thanks!
White balance with Colored lights
Francesco Andreoli posted a topic in LightingHi everybody, I have a big doubt about White balance. I know how it works with the tungsten light, fluorescent or HMI but my question is: what WB I have to setting in camera if I have colored light (with gels) as key light? what is the best setting to maintain a good skin tones? For example, in the picture below.. (lighting with kinoflo + pink gel) Thank you so much for your help
Tungsten to Fluorescent gel
Petter Englund posted a topic in LightingHello, Looking to buy the right gel for balancing my tungsten Blondies to match the color temperature of my daylight balanced fluorescent panels. At first I thought I'd just gel the Blondies with a full CTB, but then I saw the 241 "Fluorescent 5700K" gel. It looks more teal than blue, I'm guessing they added a little bit of green to compensate for the green in the fluorescents. I'm a beginner with using flo-lights, so my questions is - would I be better of with the 241 on the Blondies OR doing the full CTB on the Blondies in addition to adding a minus green to my flo-lights? I mean, I wouldn't want that extra green in the flo-lights anyway, right? For the second option, any experience on how strong a minus green I'd need? And also, for those of you regularly using fluorescent panels without any other type of lights involved, do you always add a minus green (and in what strength) as a rule of thumb? For the record: I'm not on an original Kinoflo kit, but the cheaper competitor "Flo-lights". Thank you and have a good weekend!
Gelling Par 64's
Markus Haken posted a topic in Lightinghey guys, i'm planning on using par 64s to create strong shafts of light coming through a row of windows, imitating moonlight. The action will be backlit entirely by this, some fill being provided by redish alarm lights in the foreground (practicals). I have never used par 64s before (but they make sense in terms of budget), so I'm unsure regarding the following issues: - in order to give the pars a blueish tint, i will have to gel them with some degree of ctb. how much light will i loose doing this / is the loss as significant as with tungsten lights? - i want my light shafts to be rather large, filling whole windows. i'm unsure whether i would need to go with a nsp in order to provide the necessary beam structure and if this will cover an area too small. will i be ok with a wide flood bulb or will it be impossible to get a strong shaft out of this? the interior will be hazed, of course. thanks for your help. best, markus