Brad Dickson

As noted in a previous post many ballasts are designed for world use. They will have an operational voltage range they can work in and a frequency they can work in. This should be noted on the ballast itself along with other ratings. Some ballast will adjust to the various ranges automatically while some older units required you to adjust the setting via a switch setting. Best would be to gain access to the ballast manufacturer if the information is not available. You may also find that some breakers will trip even though the current draw is below the rated amperage of the HMI. This is some times dependent upon the breaker type and can happen upon striking the HMI. GFI breakers can have problems with HMI units, thus causing them to trip.

I agree the first step is to be observant of lamp differences with your eyes. If shooting video another method for comparing lamps is to bend a white card in half allow the light source you are trying to match to light one side of the card and light the other side with the other light source. Simply frame the card so the fold sits in the middle of frame and the white card fills the frame. You should see on the monitor the difference between the two whites. Simply add you correction gel to the light you are correcting until you get both sides looking white.

As you are shooting video you could go completely different if you will be editing this item and have keying capabilities in your NLE software. Why not position your cameras before the interview and roll on a properly exposed background then reset your cameras inside as per your setup with your guest lit against a keyable background. You may even be able to have the sunlight be your subjects light source if you have the "non window" opening to your back. No extra lights just a keyable background setup. I know the look will depend upon the quality of your software and it is a "cheat" but maybe your client will accept it. Others have noted some background light reduction in combination with raising light levels and I agree they offer valid options. Just offering alternate ideas.

To get an interesting picture of HMI and other arc sources look at their spectral distribution and then look at the sources spectral distribution you are trying to match. Obviously this will not be done on set but you can get an idea of spectral distribution differences by looking at lamp manuafacturers data or search the internet. Judging an Arc on it's kelvin rating doesn't give you the full picture. A good article relating to Kelvin and Fluorescents is located here http://www.cameraguild.com/technology/kelvin.htm As others have noted their are alot of factors that influence the output of an Arc, bulb life, burn time etc. Put 60 moving lights in the air point them onto a stage floor and look at the differences even when they use the same type of arc bulb. When working in video I find the vectorscope the best reference as to where the spikes and shifts are to any arc. As many have said check your lamps and don't just go by what you assume they are suppose to be because they have been given a Kelvin rating by the manufacturer.

I have used ND in an opening with no glass by simply creating a wooden frame for it and butting the gel side by side and joining it. I have also gone with scrim over ND to get a good light reduction with reduced light reflection due to the scrim being in front of the gel. However since there would be variable daylight conditions he woudn't know the level of ND until day of the shoot. The benefit of the Roscoview is that it is variable and can be adjusted by simply rotating the camera's polarizing filter. Yes the option of going to HMI and increasing the interior light level is valid but if increasing the light level is not an option due to power limitations, heat, guests personal preference, higher levels causing sqinting, then light reduction maybe an option. Doubling a net would not be good as it would give a "moree' effect" as he noted. However theatrical scrim (such as black shark's tooth scrim)could be an option since it is more dense than netting and would not be reflective. Just a suggestion in regards to reduction methods but as others have noted increasing light levels is an option also.

I know there is a reluctance to rent but you sould consider a top cyc light such as a coda or Iris 1 style of fixture. Altman also have top cyc units as does other manufacturers. Top cyc units are designed to give a wide vertical spread. If not a top cyc perhaps use your broad fixtures in combination with a matte silk gel to spread the light. You could also diffuse the top of the unit to spread, diffuse and reduce output.

I would suggest you investigate Roscoview as a possible solution to your windows. http://www.rosco.com/canada/promotions/Ros...ew%202_0001.wmv The video (windows media player needed) link shows its effect on a window. Polarizing film for the window , polarizing filter on the camera. Just a note it is not cheap. Contact Tom Schwartz of Rosco Canada about this product. http://www.rosco.com/canada/directory/index.asp I have samples of this product and it works.

Having worked in WYSIWYG, LD Assistant, 3D Studio, ESP Vision and have been shown Rosco's software, Martin's software, along with a host of other pre viz software not one of them does it all well. Having looked at your product video I doubt people are going to have the time to wait on radiosity renderings. If you have a very fast rendering system and can simulate going through various types of diffusion etc. you may want to license it to other software developers. However I suspect to keep your price low and to keep it all real time you'll best to keep it simple and stay with basic sources. Keeping an up to date library of fixtures with their photometrics is what makes the difference in lighting software. I personally find the pre viz portion of the software to be a general idea to convey a concept and not to be photo accurate. I have a friend who does 3D work for the Royal Opera House in London. For stage work it is a real time saver but for film with so many light sources being soft a real time renderer that requires a basic computer to render may be hard to accomplish. However the other software rendering programs don't cater strongly to film so if you accomplish this it would be good.

The fact that both slots are going sideways I suspect it is not 120V but 208V or higher depending upon the location of the intallation. You may want to meter the outlet to see voltage etc.

I was the lighting director for KITH for the video portion in the last two seasons of the show. I didn't work on the film sections but a co worker was the gaffer on the show. Looking at the picture it doesn't look like any of our in house sets or props from the time so I assume it was a location at an actual restaraunt therefore real infrared heat lamps. The hot spot reflection in the silver looks like a filament of an RFL spot infra red lamp. I know you already went the heat lamp route so you should obtain a similar look.