Coronado ST 90/800 SolarMax II BF15 0.5A Double Stack OTA

Double Stack: Every SolarMax telescope comes equipped with double stack technology, featuring two etalon filters arranged in series. This configuration reduces the half width of the light passing through the H-alpha line to less than 0.5 Angstroms. Without double stack, the half width remains below 0.7 Angstroms. You can find the half width specified in the product name and technical details of the telescope.

The smaller half width enhances contrast, rendering the Sun’s structures with a three-dimensional appearance. Consequently, the image appears darker and requires precise adjustment using the tuning system due to the filter’s reduced half width.

BF Blocking Filter: Integrated within the deflection optics alongside the eyepiece receiver, the blocking filter is a crucial component of the solar telescope. It diminishes the brightness of the solar image and must under no circumstances be removed! For purely visual observing, a small blocking filter is sufficient, but for photography, a larger one should be selected.

Sol Ranger: Aligning a telescope with the Sun can be more challenging than expected and may involve inadvertent glimpses of the Sun with unprotected eyes! The Sol Ranger finder scope, utilizing a ground glass screen, facilitates easy, safe, and quick alignment of your telescope with the Sun.

Delivery includes a Cemax eyepiece, specially optimized for observation in H-alpha. These eyepieces have no 'filtering effect' and can therefore also be used at night.

SPECIFICATIONS

Optics:

Bandwidth: < 0.5

Type: Refractor

Type of Build: Solar H-Alpha

Aperture (mm): 90

Focal Length (mm): 800

Aperture Ratio (f/): 8.9

Resolving Capacity: 1.28

Max. Useful Magnification: 180

Double Stack: Yes

Blocking Filter (mm): 15

Tube:

Tube Construction: Full Tube

Focuser:

Type of Build: Helical

Mount:

Type of Build: OTA

Mounting Type: No Mount

Included Accessories:

1.25'' Eyepieces: 25mm

Tube Clamps: Yes

Finder Scope: Solar Finder

Miscellaneous:

Transport Cases

General:

Series: SolarMax II

Area of Application: Sun (H-alpha)

Recommended for:

Beginners: No

Advanced: Yes

Observatories: No