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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.
Baader Photometric SLOAN/SDSS z-s' Individual Filter
Baader Photometric SLOAN/SDSS z-s' Individual Filter

Baader Photometric SLOAN/SDSS z-s' Individual Filter

by Baader Planetarium
SKU BAA-2961700Z
$182.00 - $883.00
$182.00
$182.00 - $883.00
$182.00
Price Match Policy!
  • Photometric filter for the SLOAN/SDSS z-s' bandpass
  • Conforms to the Sloan Digital Sky Survey photometric system standard
  • Enables calibrated, scientific-grade data acquisition
  • Ideal for exoplanet transits, variable star monitoring, and photometry of faint objects
  • Available in 8 formats from 1.25" mounted to 100x100mm unmounted
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Baader Photometric SLOAN/SDSS z-s' Individual Filter

    The Baader Photometric SLOAN/SDSS z-s' Filter is a specialized optical tool designed for research-grade data acquisition in the near-infrared. By precisely matching the z-s' bandpass of the Sloan Digital Sky Survey photometric system, this filter allows astronomers to produce calibrated, repeatable measurements that are directly comparable to professional survey data. Offered in eight distinct formats, from 1.25" round mounted to 100x100mm square unmounted, the Baader z-s' filter integrates seamlessly into imaging systems ranging from advanced amateur setups to observatory-class instruments.

    SLOAN/SDSS z-s' Standard: Calibrated Photometry in the Near-Infrared

    This filter's transmission curve is engineered to isolate the specific near-infrared wavelength range defined by the SLOAN/SDSS z-s' standard. This adherence to a universal system is critical for scientific applications, as it removes the guesswork from data analysis. Your measurements of variable stars, supernova light curves, or exoplanet transits can be reliably cross-referenced with global astronomical databases.

    The z-s' band is particularly effective for observing cooler, redder stars and highly redshifted distant galaxies. For serious imagers, using a filter calibrated to this standard is the difference between taking a picture and collecting scientific data. It ensures that every photon captured contributes to a valid, publishable measurement.

    Multiple Formats for Diverse Optical Systems

    Baader offers the SLOAN/SDSS z-s' filter in a comprehensive range of sizes to accommodate virtually any telescope and camera combination. This ensures that you can maintain photometric consistency whether you are using a small refractor or a large Ritchey-Chrétien telescope.

    • Standard Mounted Filters (1.25" & 2"): These thread directly into standard filter wheels and accessories, making them a plug-and-play solution for most amateur telescopes.
    • Unmounted Round Filters (31mm, 36mm, 50mm): These sizes are designed for popular astronomy camera filter wheels, providing a perfect fit while minimizing the potential for vignetting with larger sensors.
    • Unmounted Square Filters (50x50mm, 65x65mm, 100x100mm): Intended for large-format CCD and CMOS cameras found in professional and university observatories, these filters provide full illumination for the largest sensors on the market.

  • What is the Baader SLOAN/SDSS z-s' filter used for?

    The Baader z-s' filter is a scientific instrument used for photometry—the precise measurement of an object's brightness. Its primary applications include tracking the light curves of variable stars, detecting the dip in starlight caused by an exoplanet transit, and measuring the brightness of supernovae and other transient astronomical events in the near-infrared spectrum.

    Why is the "photometric" designation important for the Baader z-s' filter?

    A "photometric" filter guarantees that its light transmission profile strictly adheres to a scientifically recognized standard, in this case, the Sloan Digital Sky Survey (SDSS) system. This ensures that data collected with this filter can be accurately calibrated and compared with data from other observers and professional surveys worldwide, making your results scientifically valid.

    Which size of the Baader z-s' filter do I need for my imaging setup?

    The correct size depends on your filter wheel and camera sensor.

    • 1.25" and 31mm filters are suitable for cameras with smaller sensors (e.g., Four Thirds format).
    • 2" and 36mm filters are recommended for cameras with APS-C sized sensors to prevent vignetting.
    • 50mm round or 50x50mm square filters (and larger) are necessary for full-frame and larger professional sensors to ensure the entire sensor is evenly illuminated.

    Can I use the Baader SLOAN/SDSS z-s' filter for visual observing?

    No, this filter is designed exclusively for instrumental measurement with CCD or CMOS cameras. Its bandpass is in the near-infrared, where the human eye has very little sensitivity. It will not produce a useful visual image and is not intended for looking through an eyepiece.

    How would the Baader z-s' filter help in observing a variable M-dwarf star like Proxima Centauri?

    M-dwarf stars are cool, red stars that emit a significant portion of their light in the near-infrared. The Baader z-s' filter is optimized for this part of the spectrum, allowing a camera to capture maximum signal from the star while rejecting other wavelengths. This results in a higher signal-to-noise ratio and more precise measurements of the star's brightness variations, which is essential for studying stellar flares or potential transits.

    I'm trying to confirm an exoplanet transit with my 11" SCT. Why is the Baader SLOAN z-s' filter a better choice than a standard infrared-pass filter?

    While a generic IR-pass filter lets in infrared light, its cutoff wavelengths are not standardized. The Baader SLOAN z-s' filter has a precisely defined bandpass that matches a scientific standard. When you measure the small dip in brightness during an exoplanet transit, using the z-s' filter allows your data to be directly compared to, and combined with, research from professional observatories, adding significant scientific weight to your confirmation.

  • Filter Standard SLOAN/SDSS z-s'
    Filter Type Photometric
    Bandpass Near-Infrared (NIR)
    Available Formats 1.25" Round Mounted, 2" Round Mounted, 31mm Round Unmounted, 36mm Round Unmounted, 50mm Round Unmounted, 50x50mm Square Filter, 65x65mm Square Filter, 100x100mm Square Filter
    Net weight (kg) 0.01 (1.25" Round Mounted, 2" Round Mounted, 50mm Round Unmounted)
    0.02 (50x50mm Square Filter)
    0.03 (65x65mm Square Filter)
    0.08 (100x100mm Square Filter)
    Filter size 1.25 inch (1.25" Round Mounted)
    2 inch (2" Round Mounted)
    36 mm (36mm Round Unmounted)
    50.4 mm (50mm Round Unmounted)
    50 x 50 mm (50x50mm Square Filter)
    65 x 65 mm (65x65mm Square Filter)
    100 x 100 mm (100x100mm Square Filter)
    Filter shape round (1.25" Round Mounted, 2" Round Mounted, 36mm Round Unmounted, 50mm Round Unmounted)
    square (50x50mm Square Filter, 65x65mm Square Filter, 100x100mm Square Filter)
    Single or Set? Single Filter
    Filter mounted Mounted (LPFC 6mm) (1.25" Round Mounted, 2" Round Mounted)
    Unmounted (36mm Round Unmounted, 50mm Round Unmounted, 50x50mm Square Filter, 65x65mm Square Filter, 100x100mm Square Filter)
    Filter Usage SLOAN, CMOS, CCD
    Special Features Life-Coat™ Warranty
    Filter Thickness (without cell) 2 mm (1.25" Round Mounted, 2" Round Mounted, 36mm Round Unmounted)
    3 mm (50mm Round Unmounted, 50x50mm Square Filter, 65x65mm Square Filter, 100x100mm Square Filter)
    CWL (Central Wavelength) SLOAN-z-s'
    Transmission Range Transmission according to SLOAN-Specification
    AR-Coating Reflex-Blocker™ hard coated, planeoptically polished
    Suitable for f/ratio f/15 to f/1.8

    • Baader Photometric SLOAN/SDSS z-s' Filter (Selected Size)

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  • Baader Planetarium Warranty