Astrodon LRGB Gen2 E-Series Tru-Balance Filter Sets
Astrodon LRGB Gen2 E-Series Tru-Balance Filter Sets were designed for cameras containing the full-frame KAF8300, KAF3200, KAF6303, KAF16200, KAF16803 sensors, as well as most Sony and back-thinned sensors and other cameras with Progressive Scan, Front Illuminated or Back-Illuminated Sensors.
Astrodon E- & I-Series Filter Scans
Astrodon Filter 1.25 Cell Customer Drawing
Astrodon LRGB Gen2 E-Series Tru-Balance Filter Sets have revolutionized CCD imaging. Their popularity is due to their ease-of-use, high optical throughput and great resulting colors for galaxies, star clusters and nebulae.
E-Series filters are designed to approximately equalize the flux of red-sensitive full-frame (formerly Kodak E-Series) CCD detectors, including compensation for the solar photon flux. This means that your RGB color combine weights will be approximately 1:1:1 within perhaps 10% for equal length exposures. This can never be perfect, but it does allow you to take one exposure time for all of your RGB data and therefore, only just one corresponding dark exposure time. Again, this saves you precious imaging time and thus, simplifies your imaging.
- Set includes Luminance (NIR/UV-blocked colorless), Red, Green and Blue filters
- 1.25" mounted, 31, 36, 49.7 mm dia, 49.7 mm square (36 mm filters will not exceed 36.1 mm dia.)
- 3 +/-0.025 mm single 1/4-wave fused silica substrate before coating
- 30 arcsec parallelism
- ~1:1:1 color combine weights for G2V white-point for Full-Frame (E) detectors
- Best choice for back-thinned and Sony detectors
- Equal RGB exposures and one dark time
- Better color separation (see spectra)
- Better color rendition for galaxies based upon color theory
- Significant reflection and star halo reduction
- Enhanced contrast for HII regions in galaxies due to narrower red (not orange) filter
- Spectral "gap" between green and red filters to minimize effect of light pollution, especially from high pressure sodium street lamps (see spectra)
- Highest efficiency blue filter with less UV
- Correct "teal" OIII color for planetary nebula (OIII signal >97% in blue and green)
- Parfocal with Astrodon's high-performance narrowband, Clear and Near-IR Luminance filters
- Ultra-hard and durable sputtered coatings coated to the edge of each filter
- Proudly made in the U.S.A.
Astrodon LRGB Gen2 E-Series Tru-Balance Filter Sets were designed for cameras containing the full-frame KAF8300, KAF3200, KAF6303, KAF16803 sensors. They are also a good choice for the latest Sony and back-thinned sensor or any camera with a Progressive Scan Sensor, Front Illuminated or Back Illuminated. The E-Series red filter is a deep red filter about 60 nm wide, which excludes much of the light pollution from high pressure sodium street lamps. Other filter suppliers try to "force fit" their orange filter (designed for the interline KAI11000, KAI2000 sensors) for use with these full-frame sensors. Their orange filter is about twice as wide spectrally as our deep red filter. As a result, their orange filter tends to "wash out" HII regions in galaxies and detail in nebula. Their blue and green color weights are no longer balanced and as a result, the OIII color in planetary nebula is skewed strongly toward blue, rather than the correct teal color. These are the reasons why Astrodon designed E- and I-Seriesfilters for these different classes of cameras for optimum results.
Notice that Astrodon LRGB Gen2 E-Series Tru-Balance Filter Sets are coated to the edge. Other filters leave an uncoated "rim" near the edge that must be blocked by a mask or the design of the filter wheel. Our approach minimizes stray light from polluting your image.
"I would like to take a minute to comment on the 50mm Gen 2 filters that I have installed in my Apogee 16803 camera. These filters set a new bar for performance ... they have a huge color gamut and best of all, there isn't a trace of reflection even when shooting 15 minute subs at the Pleiades.
The total color response can be seen in the M33 sample ... note the abundant HII regions, the strong blue response, and the brilliant yellow of the star. The superior color response isn't subtle ... it's obvious ... and all this with LRGB ... no narrow band needed! These filters are a joy to work with. Major kudos."
"For several years I happily used a set of common filters under the assumption that there was nothing unique about other filters on the market. I was wrong! Since switching over to Astrodon filters, the color fidelity of my pictures has improved dramatically! Not only do they reduce or eliminate the need for color balancing during post-processing, their precision bandwidth cut-offs result in more vivid colors and the H-alpha filter has helped me surface structures my previous filters simply did not allow my camera to capture. Astrodon filters are essential tools for serious astrophotography."
Should I get Astrodon E-Series or I-Series LRGB filters?
The answer is that it depends on your camera sensor. Progressive Scan camera sensors ( including both Front Illuminated and Back Illuminated sensors) use the E-Series LRGB filters. Interline Transfer sensors should use the I-Series LRGB filters. Finding out what type sensor your camera uses can be difficult. This information is not often included in the specifications or even the manual. So it is best to check with the sensor manufacturer. If you absolutely can’t find out, then go with the E-Series and you will be fine.
FLI has put out a convenient list that specifies which type of sensor is in their camera. Since you usually know what sensor is in your camera (and different camera brands often use the same sensor) , this handy list can be used for other camera brands as well. But again, checking with your camera manufacturer and asking if their sensor is Front Illuminated, Back Illuminated, or Interline Transfer is your best bet.
Filters in stock ship usually ship within 1 week. Filters on back-order ship usually ship within 3-6 weeks.
You may click the “Get an alert” button to be notified when an out of stock filter is back in stock. It is necessary to pay for back-ordered filters immediately to reserve your spot in our wait list. Often we have more orders for out of stock filters than we have incoming filters. Many Astrodon filters are perpetually out of stock for this reason.
The set of 1.25" LRGB filters were a complete disappointment to me. First off the filters came covered in particles and some kind of residue that would not 'just blow off with a bulb blower". But the worse part was that two of the filters were so loosely fitted to the metal casing that they were rattling in it and another filter was completely disassembled. Farpoint quickly took my set back for refitting and two weeks later sent the same set back to me. They reassembled the filter that was fallen apart and tightened the other one. Problem is they forgot to tighten the second fitler that was also rattling and the residue and particles were left the way they were. I contacted them and they quickly sent a replacement filter. I attempted to clean the filters using every method that I could find in the astronomy forums with no success. I even tried using the method recommended by Optical Structures themselves in their YouTube tutorial, but they conveniently did not address or answer the question on the comments on how to clean MOUNTED filters without leaving streaks. So I attempted to contact them a third time at which point they stopped replying to my emails. So here we are a month an a half after buying these filters which I have yet been able to use. I gotta say for a "premium" set of filters I am not impressed with the sample I got. Giving three stars because I know for a fact that others have gotten great samples and have had great success with them.