A View From Behind The Meter
I’m in the process of trying to set up what I have termed a “Lighting Lab.” By this I mean a place where lighting technicians can set up new manufacturer’s products and compare them with similar instruments by a competing manufacturer. The room will have requisite meters available for the customer to make readings with incident, spot, color temperature, and the new buzz word CRI meter, There is a great deal of confusion with regards to the new LED fixtures. When one searches the net there is a plethora of information that is clearly outdated. In one such article I read that there are no LED’s with a CRI above 90 and that is just blatantly false. I read LED lighting instruments almost every day now with ratings above 94 CRI and actually more stable than present HMI’s and fluorescent fixtures being used everyday.
Most of the misinformation stems from the early 1 x 1 Litepanels introduced in 2005 which didn’t have a great deal of consideration for CRI. In 2005 most of us were unconcerned with CRI and considered only color temperature and brightness as the primary element of a lighting fixture. These early 1×1’s had a very low CRI, actually in the mid seventies in many cases, and it didn’t seem to matter to the gaffers using them. Most rental companies acquired a number of the instruments, established a rental price, and began to put them into the technician’s hands. One could obtain daylight or tungsten 1×1’s in either spot of flood and CRI wasn’t even a consideration that anyone spoke about. It wasn’t until 2009 that I began to hear rumors about inaccurate color rendition. SMPTE did a study somewhere around that time and came up with clearly obvious color discrepancies and that started the buzz. In 2010 we did a color test with a Director of photography using plasma, LED, tungsten, HMI, and fluorescent systems that were available using a RED I camera and color charts. The results were conclusive. Certain colors changed hue depending on what instrument illuminated the chart.
The changes were I have to admit pretty subtle but that fine difference could be trouble when a client’s logo had to be the color they expected. From that point on, lighting technicians began asking about CRI more often than color temperature accuracy and it did make sense. Color temperature was already quite varied in the HMI instruments. I don’t think I ever went out with HMI’s that all had the same color temperature. Once I made the mistake of mentioning to a DP that fact and from that time on we had to make gel pacts for all HMI’s so that they all illuminated with the same color temperature. I’ve seen HMI’s vary 1,000’s of degrees especially new globes that haven’t had time to burn in for several hours. Just generally HMI’s color temperature varies with each globe installed. Fluorescent fixture change color temperature over time and most rental houses do not check color temperature on these rental items. If an instrument is labeled daylight the rental technician assumes that it is 5600 degrees and the same goes for tungsten systems with the 3200 degree assumption.
One of the things I’m hoping for, in establishing this lab, is that it will take the assumptions out of the equation and valid comparisons can easily and simply be conducted. When considering purchasing a Litepanels Inca 6 put an Arri 650 Watt tungsten instrument side by side and make accurate readings. Were all familiar with what a tungsten fixture can do in the field and the Inca needs to compare favorably in order for one to justify the expenditure. All the data expressing the savings in amperage consumption or the greatly reduced heat signature means nothing if the light won’t match what one is used to getting out of the instruments presently in use. The lab should greatly reduce the unanswered questions one has regarding newly manufactured instruments and dispute or confirm the prevalent web info that seems to be proliferating the blogs.
The other element the lab will be able to show is the difference between cheap LED’s and the high priced spread. There is always a question as to whether one is spending more than necessary in order to obtain a product. There is in the back of everyone’s head the question: “Could I have purchased a cheaper instrument and still got my money’s worth?” Putting the expensive equivalent alongside the cheaper model allow the buyer to both test and evaluate the strong and weak factors of both. I’ve been looking at a Fresnel instrument from China that is LED based and is equivalent to a 1k Tungsten Fresnel, however, to its credit, it can be battery operated, it has a DMX control, it has a built in dimmer, and is bi-color. The Mole 1K Tungsten Fresnel is priced at $669.00 from B& H and the Taiwan LED is retail priced at around $950.00 so the difference in price is relatively similar but the advantages of LED are quite considerable when making comparisons. The heat signature alone is a game changer for me and when adding the dramatically reduced amperage draw I’m sold. The instrument now has to perform the same job that the tried and true 650 has done for me for twenty years. That’s when the LAB comes in to play. There is nothing like putting your hands on a fixture to tell you whether you’re going to be comfortable working this instrument on location. All the questions then come to the surface as you begin to manipulate the light. Such things as weight, sense of durability, flood and spot movement, evenness of light pattern, and finally is the quality of light matching one’s expectations all come into the picture. Matching side by side instruments in a controlled environment eliminates much of the insecurity of purchasing and will clear up any misinformation that might be present in your thinking. That’s what I hope the LAB will do for our customers. The client answers their own questions directly and doesn’t have to rely on manufacturer’s brochures for detailed information. “Read it and weep” as the saying goes and the lab with the meters available for the customers can make that thought a reality.
This afternoon I will begin a series of video blogs on specific LED manufacturers and their LED products that I feel as though are viable for our industry so look in on the LAB and the blogs with the awareness that our industry is definitely changing and you might want to get as much information as you can find to make your choices for the future. Welcome to the Birns And Sawyer Lighting LAB.
-Michael Rogers, Lighting Consultant and Educational Outreach