1. What is the DayStar Quark "Eyepiece"?
The DayStar "Original-Style" Quark Eyepiece Filter is a special type of combination filter/eyepiece holder that allows you to view the Sun in Sodium-D light with most refractor telescopes. Although DayStar and some other sites refer to this item as an eyepiece, and while it may look like one externally, note that it is not an actual eyepiece.
The Original Quark is meant for use on refractors of f/4 to f/8 focal ratio (see additional details in section 4 below). Just insert the Quark into your diagonal, add a 1.25" eyepiece, warm it up, and view! This device essentially converts your normal refractor telescope into a narrowband solar telescope.
The new, all-in-one design of the Quark marries high quality components of a telecentric barlow, adapters, snouts (nosepiece barrels), and Daystar Sodium filter into one simple assembly. Through design efficiency and optimization, users can now enjoy the known high quality optics of DayStar at an affordable price. Baffles have been added to increase contrast and AR coatings are optimized for the 589nm wavelength.
The patent pending QUARK contains a custom Daystar Instruments 4.2x telecentric barlow lens fully optimized in coatings and optical design specifically for the Sodium D-Line wavelength. This highly specialized telecentric lens offers superior field flatness. However, your telescope will now operate at a much higher focal length, and you will need to use longer focal length eyepieces to get reasonable magnifications. For example, a native f/7 refractor will operate as an f/29.4 scope with the Quark inserted.
2. Why Sodium D-Line?
Sodium will show high resolution sunspot details, plague, granulation, and possibly super-granulation depending on resolution and seeing conditions local to the observer. Sodium can also show flare footprints, also known as flare kernels - that is that a flare will begin and emit light in Sodium at the two ends first, before erupting in white light. The Sodium line is brighter than both Calcium and even Hydrogen Alpha lines, so it is easier for observers to see and photo exposures will be shorter.
The exact bandpass of the Quark Sodium D-Line you receive will be 0.5 Å or lower. DayStar does not mark individual units with their specific FWHM bandpass, and we cannot test and cherry-pick specific Quarks for customers.
3. How do I use a DayStar Quark?
As mentioned above, just insert the Quark into your diagonal on compatible refractor telescopes, insert your eyepiece in the Quark, warm it up, and enjoy high-powered views of the Sun. The fully optimized design of the Quark eliminates the need for any additional adapters. It is all combined in one lightweight eyepiece-sized device.
The Quark requires a power source for operation and it needs to be plugged in and warmed up for about 10 minutes before you can use it. A wall-mounted AC adapter is included for this. They have even reduced power consumption, so the Quark can now operate all day off a small, palm-sized optional battery pack.
Note that changing the focus of the telescope requires the Quark to retune, and this again requires a few more minutes for the unit to stabilize before you get the best views of the Sun again.
4. What telescopes can I use the DayStar Quark with?
This original-style Sodium Quark performs best on f/4 - f/8 refractors. Longer focal ratio refractors can also use the Quark, but the image may be dim.
For refractors up to 80mm in aperture, the thermal load is low enough on the optical system, and you do not need any additional front or rear mounted Energy Rejection Filters (ERF).
For larger refractors up to 150mm, you can safely use a suitable rear-mounted UV/IR cut filter (not included), available from several different maufacturers. The UV/IR cut filter functions as the ERF and it should be mounted in front of your diagonal.
Users should consider front-mounted ERF filters (available separately from DayStar) for refractor telescopes larger than 150mm in aperture. The Sodium Quark is compatible with DayStar's Yellow glass ERF. It cannot be used with the Red glass ERF as it will not pass the Sodium line.
5. Additional Specifications / Features
- 1.25" or 2.0" combo nosepiece with safety indent slot slides directly into diagonal or focuser
- Standard 1.25 eyepiece drawtube output with optional 2" eyepiece holder available separately
- Brass compression ring to protect eyepiece
- Uses USB power, 5v 1.5amp
- Includes 90-240V AC wall adapter with international plug adapters
- 5 year US warranty
- Optional 8-hour battery pack available
- Integrated, fully baffled 2 element telecentric 4.2X barlow optimized for 589nm
- Integrated 12mm blocking filter with 21mm clear filter aperture
- No aperture limitations. May be used on larger refractors (with suitable ERF) for higher magnification views
- Ships in convenient twist-case for safe, dust-free storage
- Not suited for off-axis applications
- Optional T-mount or C-mount adapters available separately for using the Quark with imaging or video cameras or other accessories
- Uniformity: SE (Standard Edition)