Monday, September 13, 2021

NGC-7000 meets K-4415

North America Nebula, Nikon Z7 II, 300mm/f4
On two separate evenings last week I made nighttime activations of POTA K-4415.

By far, the best part of it all wasn't the radio-activity or the astrophotography - it was simply the being there. Alone, at night, under a clear, star-filled sky.

The Milky Way was prominent from horizon to horizon immediately after turning off the car's headlights, with my eyes not yet dark-adapted.

Maybe that's a significant appeal of this new astro-photo bug that's bitten me and I'm only just now starting to realize it.

The photo obtained is my least-favorite in the new-to-me genre but that doesn't diminish the experience a bit. I thoroughly enjoyed myself.

The photo is of the North America Nebula (NGC-7000). That other redness east of "Florida" is the Pelican Nebula. In other words, blobs of interstellar gas. Galaxies impress me; gaseous clouds, not so much. But the technology required to capture them - that piques my interest.

The new auto-guider works, and works well. I was able to make 3-minute exposures with not a hint of elongated stars. By itself, the tracker is only good for 60, maybe 90, seconds before stars start looking like the commas in this sentence. Add an autoguider and new possibilities emerge.

It works like this:

A small scope - it looks like something you'd put on a rifle - is attached to the same tracking mount as the main camera. Inserted into that scope is a CCD camera which looks like an eyepiece. It snaps a photo every 3 seconds and feeds the resulting image to a Raspberry Pi-like computer.

I connect to the computer's wifi with my Android tablet running an app that shows the star field captured by the CCD camera.

Tapping on one of the stars tells the set-up to "Track this star". The computer then outputs a correction signal to the tracker that keeps it locked onto that star - not necessarily the one I'm photographing with the main camera but, since they're on the same physical mount, the main camera's target is tracked too.

Once all this is going, I set the Nikon's intervalometer for a series of 3-minute exposures, then head to my car, open the Thermos of coffee and start making caffeinated POTA contacts.

I didn't expect much activity at that late hour but managed to put 20 contacts into the log over the course of 90 minutes. That's with me checking the camera & mount every 15 minutes to convince myself that it really does work.

Mostly CW, some phone. FT-891, HamStick whip on the car, Bioenno battery.

I should have laid out at least a couple radials - I'll do that next time.



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