Celestron 0,7x Reducer for EdgeHD 800 - 30mm illumination circle

Celestron EdgeHD 0,7x Reducer for the Edge HD 800 SC Telescope

This reducer is designed for the 8" EHD and reduces the f-ratio from f/10 to f/7. Exposure time halves and the field of view increases by 43%. With 30 mm illumination the reducer matches perfectly with almost any astro camera and DSLR with APS-C sensors. The outstanding 4-element design and a high-quality coating prevent reflexes. This makes remarkable astro images possible.

The backfocus from the SC thread of the reducer:

The reducer reduces the backfocus from 133 mm at f/10 to 105 mm. This slightly shorter working distance enables better illumination. 105 mm are sufficient for adding any kind of accessories like off-axis guiders or filter wheels inbetween.

If you have the optional CE820759 T2-adaptor for the EHD 800, you must unscrew the camera-heading extension tube, which gives you 55 mm backfocus from the T2 thread.

If you prefer an individual adaptation, please consider the following:

The 105 mm backfocus starts at the SC thread. We therefore recommend the TS adaptor TSSC-M48 to reach an M48 thread. The adaptor adds only 1 mm of optical length in this combination. This leaves you with 104 mm backfocus starting from the M48x0,75 male thread to the camera sensor. Of course we are willing to help you with the needed configuration.

Advantages and features of the Celestron reducer for EHD 800:

Focal length reduction to 1400 mm whilst halving your exposure time

Maximum color fidelity and transmission achieved by multi-coating

Total suppression of reflexes thanks to blackened lens edges

Special lanthanum glass for optimal results

High-quality aluminium body for an exact alignment of the lenses

Threaded cap made from metal for ideal protection - no attrition when opening

Practical advice from TS - Connection of cameras through the M48 thread at 55 mm backfocus

We always recommend an adaptation via M48 to achieve optimal illumination. Here we present one possible adaptor configuration. Starting from M48x0,75 thread you have 55 mm backfocus (T-ring and DSLR camera).

TSSC-M48 - adaptor to M48 - effective length 1 mm

M48AbstimmA1 - adjustment ring - effective length 1 mm

2x TSVF220 extension tube - length 40 mm

1x BVF208 extension tube - length 8 mm

This combination precisely adds up to 55 mm working distance from the M48 thread. You are also very flexible and can extend the working distance by removing each element.