NV Phonetography has come a long way, and if you have not seen them check out GeezerGazer’s recent thread which features the best results I have seen to date:
These results have inspired me to redouble my own efforts. (And get a new phone, mine is now two models out of date!) Old phone and cheesy adapter aside I feel I have not been using NightCap effectively, overexposing most targets. So last night I systematically shot a panel of photos to share, looking at each NightCap setting individually.
The target was Cederblad 214 (aka Sharpless 2-171) a very bright nebula in Cepheus. Nothing special about that target selection. It is a detailed target with bright areas, a tiny cluster, dark lanes and features.
The scope used is a Takahashi Epsilon e180, 180mm aperture working at f/2.8. My NVD is the Mod 3C with L3 intensifier (white). I was working at prime focus.
One of the variables I have been obsessing about was gain setting on the NVD. However, I noticed something when I attempted to focus using a zoomed view on the iPhone screen: the phone adds it own scintillation! Based on that I made the decision to turn NVD gain to Full and let the NightCap software average it out.
Likewise, to minimize variables I used a 7nm filter, 1/3 second exposures (iPhone X max setting), 20 second averaging runs, and held ISO to 3200 in the early frames (ISO Boost = LOW to enable 3200 speed). Changes from that protocol will be noted as different parameters are compared in later posts.
Let’s dive in ...