The gear that magically outputs light to form a beautiful images can be a complex piece of equipment to understand. Here are basics to help navigate the emerging types of projectors available on today's market.
LUKE MCELROY · September 7, 2017
2. Fixed Variable Lenses.
These are going to be your lower cost projectors, where the lens is part of the design of the unit, and cannot be removed.
3. Variable/Interchangeable Lenses.
These are most common in your professional grade projectors and provide complete control over how large of an image you can project. The projector lens allows you to get the desired projection image size you need. Every lens will have a ratio to the number one. This factors the ability for a single lens to zoom in or out. If the ratio is not a variable ratio, then it’s a fixed lens (example 1.0-2.0:1 is a zoom lens and a 1.2:1 is a fixed lens).
For ultra-short throw lens, Hitachi is by many considered a leader in the area of small projectors, but Panasonic recently introduced the ET-DLE030, which is an interchangeable ultra-short throw lens designed for their large body projectors capable of projecting a 100-inch screen from 5.57 feet away. As a rule of thumb, the majority of smaller body projectors without interchangeable lenses include a 1.8-2.6:1 lens (but always investigate this before purchasing).
Keep this in mind when you are doing your calculations. Without the right lens, you may be shooting too big of an image (and losing brightness and pixel clarity), or you may not fill the desired screen size.
Here’s the magic projector lens formula: LENS = THROW DISTANCE ÷ PROJECTION WIDTH
Let’s break this down. In order to find the exact lens required, you need two measurements: throw distance (from the front of the lens to the projection surface) and width (the width of your projection surface). In some cases, this formula doesn’t work exactly (i.e., unique size chips and nonnative resolutions). The most common situation, in which this formula isn’t exact, is when a projection surface’s height is greater than its width.
There are a number of great iOS and Android apps, such as Projector and Lens Calculator, by PROLUXON (available on iOS), that make this process simpler. One thing to keep in mind, whether you’re doing the math old school or with a lens calculation app, is that the aspect ratio is native to your projector. If you do the lens calculation for a projector that is native to 16:9 aspect ratio and you want to show a 4:3 image, your math needs to be completed using the least common denominator of the 16:9 ratio.
For example, if you want a 4:3 image that is 16-feet wide by 12-feet tall on a projector with a native 16:9 aspect ratio, you will need to do your math based on a 21-foot wide by 12-foot wide image. This is because the projector’s internal image-processing chip can’t add pixels to the top and bottom of the projected image. In order to get a 4:3 image out of a chip working with a 16:9 aspect ratio, realize that some pixels on either side of the image will not be used.
Overlooking this detail has resulted in numerous miscalculated projection lenses over the years, and I’m hoping you can learn from those mistakes. In the end, there’s never a one-size-fits-all approach to projection technology, but I hope that this guide has helped to simplify the mystery behind choosing the right projector for your application.
There may be times your church can save by getting an LCD projector, and other times you need laser. There may be times you can save by using a fixed variable lens and other times you may want to purchase that locked in interchangeable lens. Regardless, knowledge of the tool will always maximize your impact with the art.
Luke McElroy is the founder of Orange Thread Media, the parent company to TripleWide Media, SALT Conferences and Orange Thread LIVE. He is the author of The Wide Guide: Blueprint for the Multiscreen Movement. Through his leadership, Orange Thread’s work has been seen around the world with well known brands including American Idol, Blake Shelton, Bill Engvall and hundreds of churches every week through the stock media their team has created. Luke was named one of the top innovators in the church by Worship Leader Magazine in 2013 and made the Impact 100 “List of Entrepreneurs to Watch Under 30.” He currently lives in Nashville, Tenn.