CONVERSION TYPES:
1A. UV/IR blocking filter removal with LPF
(Enhanced Spectrum: Visible + H-Alpha + Sulfur II)
This conversion preserves the Low Pass Anti-Aliasing filter with self-cleaning function. The spectral sensitivity of the camera sensor will be Enhanced Spectrum (For a complete description of a ES conversion please read options 2A or 2B), allowing Hydrogen Alpha and Sulfur II wavelength emissions pass but still blocking UV/IR light. The main purpose of the LPF is eliminate moire effect but at the cost of sacrificing sharpness slightly introducing a little blur effect and it also reduces color noise. With the Low Pass Filter only preserved, in most cases the sensor distance to the lens bayonet can be adjusted accordinly to match the diffraction index differential to reach perfect focus to infinity with lenses. The sensor repositioning distance range can be confirmed once the camera is disassembled. Perfect focus of subjects closer than infinity with lenses can still be achieved, but for focus to infinity with lenses capability option 2A is guaranteed for all models and options 2B and 3 are guaranteed for most models. Telescopes will always reach focus to infinity without any problem.
1B. UV/IR blocking filter removal without LPF
(Full Spectrum: Ultraviolet + Visible + H-Alpha + Sulfur II + Infrared)
This is the most unexpensive conversion, most recommended to save money. Having the sensor bare or "naked" the camera will become Full Spectrum (For a complete description of a FS conversion please read option 3). With the bare sensor modification, the sensor distance to the lens bayonet will be adjusted to reach focus to infinity with lenses when a Clip-in body filter like the Astronomik L-2 UV/IR blocking or CLS is attached to the camera body. When combined with a Clip-in filter like the Astronomik L-2 UV/IR blocking or the Clip-in MC Clear glass, the total price of this conversion is less than the internal filters modifications.
Without any glass above the sensor there are no internal reflections coming from a replacement filter. When the stock UV/IR blocking filter is removed, the surface of the sensor is not really naked. There is a layer of glass protecting the micro-lenses and bayer filters on top of the pixels.
2A. Enhanced Spectrum conversion with Baader or Optolong Luminance Filter and LPF (Visible + H-Alpha + Sulfur II)
For this conversion, the non-detachable Baader or Optolong UV/IR Cut Anti-Reflective filter (Depending on filter availability) with enhanced H-alpha and Sulfur II sensitivity is permanently installed preserving the Low Pass Anti-Aliasing Filter with self-cleaning function. This is the most convenient modification for wide field astrophotography with lenses because focus to infinity is guaranteed in all Canon Mirrorless APS-C models. The sensor filters configuration of this modification is the same of the Canon EOS 60Da and Canon EOS Ra. This conversion does not require an additional or external UV/IR Cut filter. The camera can be used for daylight photography setting the custom white balance with a gray card shot under the specific light source for "In-Camera" white balance correction or with Adobe Camera Raw white balance presets without the need of additional original white balance filters.
Out of focus NIR: With the Enhanced Spectrum modification, depending on the lens, telescope or optical corrector used, some imagers might experience a little bit bloated stars due to the near infrared light slightly out of focus when a refractive optical system does not have at least one ED (Extra-Low Dispersion glass) element. This chromatic aberration could be mitigated with post processing correction using computer software.
2B. Enhanced Spectrum Conversion with Baader or Optolong Luminance Filter only (Visible + H-Alpha + Sulfur II)
On this conversion both Low Pass Anti-Aliasing filter with self-cleaning function and the UV/IR blocking bluish filter are removed and replaced by the non-detachable Baader or Optolong UV/IR Cut Anti-Reflective filter (depending on filter availability or camera model) with enhanced H-alpha and Sulfur II sensitivity. With the permanent installation of this filter, this conversion does not require an additional or external UV/IR Cut filter. Perfect focus to infinity with lenses capability is guaranteed for most Mirrorless APS-C cameras models. The camera can be used for daylight photography setting the custom white balance with a gray card shot under the specific light source for "In-Camera" white balance correction or with Adobe Camera Raw white balance presets without the need of additional original white balance filters. With the Low Pass Anti-Aliasing Filter removed, the Camera Sensor performs at native maximum sharpness, which is also great for solar and planetary astrophotography.
Out of focus NIR: With the Enhanced Spectrum modification, depending on the lens, telescope or optical corrector used, some imagers might experience a little bit bloated stars due to the near infrared light slightly out of focus when a refractive optical system does not have at least one ED (Extra-Low Dispersion glass) element. This chromatic aberration could be mitigated with post processing correction using computer software.
3. Full Spectrum conversion with Astronomik Anti-Reflective Clear Glass only
(Ultraviolet + Visible + H-Alpha + Sulfur II + Infrared)
The Full Spectrum modification is the best conversion for planetary astrophotography because the possibility of using infrared isolating filters like the Astronomik ProPlanet 742 IR-pass and 807 IR-pass . The infrared wavelength is significantly less susceptible to poor seeing (atmospheric turbulences) and consequently the resulting images are considerably sharper. Expert planetary imagers process planets photos with single line infrared filters as a luminance channel.
This is the most versatile conversion, is suitable for UV/IR Photography, Regular Photography and Astrophotography. The camera will capture the entire visible spectrum including Hydrogen Alpha and Sulfur II emissions plus Ultraviolet and Infrared light. Perfect focus to infinity with lenses capability is guaranteed for most Mirrorless APS-C cameras models. Both Low Pass Filter with self-cleaning feature and the original UV/IR blocking bluish filter are replaced by the Astronomik Multicoated Anti-reflective Clear filter which is permanently installed. With the Low Pass Anti-Aliasing Filter removed, the Camera Sensor performs at native maximum sharpness.
Out of focus Infrared: An additional UV/IR cut filter is required to capture the pictures in visible light. This filter is a must when imaging with telescopes using refractive elements (refractors, catadioptrics, reducers/flatteners, coma correctors, etc.) If light frames are captured without an UV/IR blocking filter you will get bloated stars, because UV and IR light rays focus at different distance from the visible light focal plane.
A luminance, or any narrowband filter will cut off Ultraviolet and Infrared Wavelengths.
For daylight or regular photography an additional Original White Balance filter is required. The Astronomik OWB Clip-in filter can be used with all lenses.
For more information
If you have any question about the modifications options, or if you are not sure which one is the best for the astrophotography application that you are planning to do, please contact us clicking here.
