1. What is the DayStar Quark "Eyepiece"?
The DayStar "Original-Style" Quark Hydrogen-Alpha Eyepiece Filter is a special type of combination filter/eyepiece holder that allows you to view the Sun in H-alpha 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 hydrogen alpha 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 656nm 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 Hydrogen Alpha 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. Chromosphere or Prominence Model - Which one should I buy?
The H-Alpha Quark is offered in two versions - the Chromosphere Model (this item) or the Prominence Model (sold separately). With this, observers can buy a filter based on their desired observing goal. Either way, you will be able to see amazing, high-powered views of the Sun in H-alpha in the scope you already own.
- The surface or Chromosphere model contains an etalon with a bandpass in the range of 0.3 - 0.5 Å (angstroms). Choose this model if want to see details on the Sun's surface. The Chromosphere model will show the highest contrast on the solar surface, and will show some broad prominences, although not in detail.
- The Prominence model contains an etalon with a wider bandpass in the range of 0.6 - 0.8 Å. Choose this model if want to see prominences in all their fine glory. This model will show some surface features as well.
Note that the exact bandpass of the Quark you receive will be in the range mentioned above, but it can be anything within that range. For example, a Chromosphere Quark you receive might have a bandpass of 0.3 Å or 0.5 Å or anything in-between. DayStar does not mark individual units with their specific FWHM bandpass, and we cannot test and cherry-pick specific Quarks for customers.
Using DayStar's superior etalon technology, double-stacking is not required to reach narrow bandpass for chromosphere or prominences. If you have to choose one Quark, pick the Chromosphere model since it allows you to view a wider variety of solar features.
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 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 (see photo 4 above).
Users should consider front-mounted ERF filters (available separately from DayStar) for the following:
- Petzval refractors
- Top-end Apo refractors sold under wait-listed conditions
- Telescopes larger than 150mm in aperture that might track the Sun for more than 6 hours
The "Original Quark" is not meant for use with other telescopes. For SCTs and Maksutov telescopes, consider the Combo Quark filter (sold separately).
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
- Tuning knob allows wing shifting +/- 0.5Å with detents at every 0.1Å
- LED indicator for power, warming, ready, fault
- 5 year US warranty
- Optional 8-hour battery pack available
- Integrated, fully baffled 2 element telecentric 4.2X barlow optimized for 656nm
- Integrated 12mm blocking filter with 21mm clear filter aperture
- Full disk viewing possible on refractors up to ~450mm focal length
- 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)
6. Important note about cosmetic finish of new Quarks
Please note that many new Quarks have what some will consider to be a cosmetic blemish on the red anodizing on the Quark barrel. These artifacts (mottling) are a product of the anodizing process that DayStar uses, and they do not indicate a defective, used or blemished Quark. Photo 5 above shows this mottling on a representative Quark.