Coronado ST 90/800 SolarMax III BF15 0.7A OTA

Observing the sun in H-Alpha is an exhilarating experience with the compact SolarMax III telescopes! Equipped with the integrated ‘True’ Etalon filter, these telescopes offer superior contrast and sharper images compared to models with smaller filters.

The SolarMax III telescopes boast an enhanced focuser with precise focusing and premium features. Moreover, the filters are removable, transforming the solar telescope into an achromat for nighttime sky observation.

At a wavelength of 656 nanometers, known as H-alpha, the sun reveals its ever-active surface and prominences at the solar edge. There's always something fascinating to observe on the sun in the H-alpha range!

RichView™ Tuning: The Doppler effect causes wavelength variations around the H-alpha line, particularly noticeable in the transition from the central solar disk to prominences at the edge. With the RichView™ tuning system, you can adjust the filter to achieve optimal contrast.

Double Stack: Each SolarMax telescope features double stack technology, incorporating two etalon filters in tandem. This configuration narrows the half width of light passing through the H-alpha line to under 0.5 Angstroms, enhancing contrast and rendering the Sun’s structures with a three-dimensional appearance.

BF Blocking Filter: Integrated within the deflection optics alongside the eyepiece receiver, the blocking filter diminishes the brightness of the solar image, ensuring safe observation. It is a critical component of the solar telescope and must never be removed.

Sol Ranger: Aligning a telescope with the sun can be challenging and risky. The Sol Ranger finder scope, with its ground glass screen, facilitates safe and accurate solar alignment.

Delivery includes Cemax eyepieces and the Cemax-Barlow, optimized for maximum light transmission and contrast with H-alpha telescopes.

SPECIFICATIONS

Optics:

Type of Build: Solar H-Alpha

Type: Refractor

Aperture (mm): 90

Focal Length (mm): 800

Aperture Ratio (f/): 8.9

Resolving Capacity: 1.53

Limit Value (Mag): 11.6

Light Gathering Capacity: 170

Max. Useful Magnification: 180

Tube Weight (kg): 7.9

Bandwidth: < 0.7

Etalon Filters (mm): 90

Blocking Filter (mm): 15

Double Stack: No

Tube Construction: Full Tube

Focuser:

Connection (to Eyepiece): 2"

Type of Build: Gear Rack

Free Aperture (mm): 51

Gear Reduction: 1:7 Fine Focusing

Connecting Threaded Socket (Camera-Side): T2

Rotating: Yes

Adjustment Range (mm): 65

Mount:

Type of Build: OTA

Mounting Type: No Mount

Included Accessories:

Prism Rail: Vixen-Style

Tube Clamps: Yes

Finder Scope: Solar Finder

1.25'' Eyepieces: 25mm, 18mm, 12mm

Transport Cases: Yes

Deviating Optics:

Blockfilter

Barlow Lens:

2x

General:

Series: SolarMax III

Area of Application: Sun (H-alpha)

Recommended for:

Beginners: No

Advanced: Yes

Observatories: Yes