K3-64 is a small dim planetary nebula in Perseus. I captured it with a UHC filter that passes OIII, H-beta and H-alpha on up to around 800nm. This gives the stars an odd color and gives a pink hue to some of the very red stars in the field. The near full moon was high in the sky behind my house, complicating capture.
There is a central star dimly visibly in PanSTARR survey images, but its so dim that it isn't in the Gaia database, so no luck determining the distance using parallax. One can estimate its distance based on its angular size (13x17 arc seconds) and a guess at its physical size of around 1 light year across for a fairly mature planetary nebula, which would put it at around 2000±600 parsecs away. There is a paper that estimates its distance based on the ratio of H-alpha to H-beta line emission which has a typically standard ratio, but the two lines are attenuated differently by interstellar dust. So with the change in this ratio you can determine the amount of interstellar dust between us and the planetary nebula and then combine this with estimates of the density of interstellar dust to get a distance. The results reported for this object are 1800±200 parsecs, again giving a reasonable phytsical size for the object. A nice web page covering using reddening to estimate distance is here:
https://web.williams.edu/Astronomy/research/PN/nebulae/exercise2.php#:~:text=The%20Phenomenon%20of%20Interstellar%20Reddening,should%20be%20roughly%20the%20same.&text=A%20planetary%20nebula%20lying%20behind,H%CE%B2%20less%20than%200.47.
Each of the seven 8 minute images stacked to produce this image were themselves a live-stack of 240 x two second exposures (live-stacked in SharpCap).
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