OPTOLONG L-ULTIMATE FILTER Size:1.25" 8mm M68 spacer is a

8mm M68 spacer is a very useful for making up the exact backfocus distance required by correctors

Additional backfocus required 15 mm

32 µs-300 s

black anodised and laser engraved

The adapter fits to telescopes like:

OPTOLONG L-ULTIMATE FILTER Size:1.25" 8mm M68 spacer is aThe new Optolong L Ultimate is a dual band astrophotography filter designed to drastically reduce the effect of light pollution. Its two ultra narrow 3nm passing bands isolate the nebulae emissions in H Alpha (red) and OIII (green blue), maximizing signal and making the sky background dark. The L Ultimate filter has been optimized for excellent halo performance. The L Ultimate is designed for use with optics not faster than f 4. For example, with a