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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
iOptron iEFW-15 5-Position Electronic Filter Wheel for 1.25'' or 31mm Filters

iOptron iEFW-15 5-Position Electronic Filter Wheel for 1.25'' or 31mm Filters

by iOptron
SKU IOP-3381
$199.00 - $199.00
$199.00
$199.00 - $199.00
$199.00
Price Match Policy!
  • Automates filter changes for astrophotography
  • 5-position carousel
  • Accepts both 1.25" mounted filters
  • Accepts 31mm unmounted filters
  • Enables unattended LRGB and narrowband imaging sequences
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • iEFW-15 5-Position Electronic Filter Wheel for 1.25'' or 31mm Filters

    The iOptron iEFW-15 is an electronic filter wheel designed to automate one of the most critical steps in deep-sky imaging. Its internal 5-position carousel allows you to remotely switch between different filters without physically touching your telescope, preserving focus and alignment. The wheel offers flexible compatibility, accepting both standard 1.25" mounted filters and 31mm unmounted glass filters for more demanding applications.

    Automated Imaging with 5 Filter Positions

    The core function of the iEFW-15 is to enable unattended, multi-filter imaging sessions. With 5 available slots, you can load a full LRGB (Luminance, Red, Green, Blue) set plus a specialized narrowband filter like H-alpha, or a complete SHO narrowband pallet (Sulfur-II, Hydrogen-alpha, Oxygen-III) with room to spare. This eliminates the need to manually swap filters for each channel, which is a primary source of imaging errors, especially on cold nights.

    Flexible Support for 1.25" and 31mm Formats

    The iEFW-15 accommodates the two most common filter formats for small-to-medium sensor cameras. You can use standard 1.25" threaded filters, which are widely available and cost-effective. For imagers using faster telescopes (f/5 or lower) or larger sensors, the wheel also supports 31mm unmounted filters, which provide a larger clear aperture to help minimize vignetting at the edge of the field.

  • What is the main benefit of using the iEFW-15 filter wheel?

    The primary benefit of the iEFW-15 is automation. It allows your imaging software to automatically switch between filters during an imaging sequence (e.g., LRGB or narrowband). This means you can run a complete multi-hour, multi-channel imaging plan without manual intervention, which is crucial for efficiency and for preventing disturbances to your optical train.

    How many filters can the iEFW-15 hold?

    The iEFW-15 features a 5-position carousel. This is sufficient for a standard LRGB filter set with one extra slot for a narrowband filter like H-alpha, or a full SHO narrowband set (SII, Ha, OIII) with two empty slots.

    Can I use my existing 1.25" filters with the iEFW-15?

    Yes. The iEFW-15 is designed to be compatible with standard 1.25" mounted filters. You can thread your existing filters directly into the carousel positions.

    Why would I choose 31mm unmounted filters over 1.25" filters for the iEFW-15?

    While 1.25" filters are convenient, their mounting cell can sometimes cause vignetting (darkening of the corners) on cameras with larger sensors or in fast optical systems (f/5 and below). 31mm unmounted filters offer a larger clear aperture, which helps ensure the entire sensor is evenly illuminated, making them a better choice for high-end imaging setups.

    What imaging sequences can I run with the iEFW-15's 5 positions?

    The 5 positions on the iEFW-15 are ideal for several common imaging workflows:

    • LRGB + H-alpha: Capture detailed luminance data, standard color with RGB, and add deep red emission detail from nebulae with an H-alpha filter.
    • SHO Narrowband: Load Sulfur-II, H-alpha, and Oxygen-III filters to create Hubble-palette images of emission nebulae, even from light-polluted skies.
    • Photometry: Load specialized photometric filters (B, V, R) for scientific measurements of variable stars.

    Is the iEFW-15 useful for imaging the Andromeda Galaxy (M31) with an 80mm refractor?

    Absolutely. For a broadband target like the Andromeda Galaxy (M31), you would load the iEFW-15 with LRGB filters. You can program your software to capture a long sequence of luminance frames for detail, followed by shorter sequences for each of the R, G, and B filters for color, all in a single automated session.

  • iOptron 2-Year Limited Warranty