California dreaming

California Nebula

Last night I decided to astro modify my trusty D5500. Up until now it had remained completely stock, doing a great job for regular photography and astro work. But by replacing the hot mirror with a UV/IR cut filter, the sensor crucially receives around 5x as much signal in the H-Alpha wavelength, opening up a whole new world of targets.

I’ve had some success with brighter emission nebulae in the past, but fainter targets such as the California nebula have always remained elusive. Although perhaps not the most interesting target, it’s secretive nature hiding away in the deep end of the red wavelengths made it a fitting target for the newly modified camera.

Waiting for the moon to set at 2am, I managed to capture almost an hour of data before the local abbey striking 3am gave me the signal to pack up. The image is a little washed out due to the short exposure times and lingering moonlight, but I could only have dreamt of registering anything but a faint smudge before the upgrade.

Image details: Modified Nikon D5500Tamron-100-400mm-f4.5-6.3 @ 400mm/f6.3. Total of 56 minutes exposure time (112 x 30 seconds) at iso 800. Tracked with unguided AstroTrac TT320X-AG. Stacked with Deep Sky Stacker. Edited with Starnet++ and Photoshop

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