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Details:
... taken through 50, 75, 150, and 600mm focal-length lenses on a Micro-4/3 sensor (so double the numbers to get the 135 format equivalent focal length).
I observed the area visually through a 3.5" scope after midnight July 6 MDT. T and epsilon are 1° apart. I started at epsilon and used the purple-outlined arc and triangle asterisms (see photo #3) to reach T at low power. The short side of the triangle points to HD 143707, a wide double, mag. 7.8 and 11.5, separated by 1'; the companion was seen with averted vision with great difficulty at 160x and not at all at 80x. T was faint enough to cause some searching around the triangle's tip at 80x, but once seen, couldn't be unseen, so quite a different, easier experience from the double's companion. I estimated its brightness against the other two triangle stars, mag 10.5 and 9.3-9.9 (the latter an RR-Lyr variable), and came up with mag. 10.3.
There are 2 other observations with these photos that have nothing to do with the upcoming nova:
- An f/1.8 75mm camera lens in dark skies can image nearly as faint stars as an f/5.6 600mm scope inside town for nearly identical exposures.
- A 30-second exposure with a 50mm lens in town can record virtually all the stars that can be seen visually in a 3" scope under a dark sky.
Photo data:
Note: EA = effective_aperture[mm] = lens_focal_length[mm] / lens_focal_ratio
#1: Panasonic GX8, TTArtisan f/1.2 50mm lens, EA = (50/1.2) = 41.6mm, photo tripod
... exposure: 7 x (f/1.2, 4 sec, ISO 1600) = 28 sec
... orientation: N upper right W clockwise; FOV: 19.6° x 14.8°; faintest star: mag. 11-12
... location: backyard in town
... date: June 8, 2024 7:00 UT
#2: Panasonic G9, Olympus f/1.8 75mm lens, EA = 41.6mm, iOptron SkyTracker Pro
... 15 x (f/2, 60 sec, ISO 1600) = 15 min
... N up W cw; 13.2° x 9.9°; mag. 15
... New Harmony, UT (dark sky area)
... June 30, 2024 6:30 UT
#3: Panasonic G9, Lumix f/3.5-f/5.6 100-300 lens @ f/4.5 150mm, EA = 66.6mm, iOptron SkyTracker v2
...20 x (f/5.6, 60 sec, ISO 1600) = 20 min
... N up W cw; 6.6° x 5.0°; mag. 13.8
... backyard in town
... July 4, 2024 9:30 UT
#4: Panasonic G9, Askar FRA 600 refractor (f/5.6 FL=600mm), EA = 108mm, iOptron GEM45G
... 17 x (f/5.6, 60 sec, ISO 1600)= 17 min
... N up W cw; 1.65° x 1.24°; mag. 15-16
... backyard in town
... June 12, 2024 9:45 UT
stacking: DeepSkyStacker processing: Paint Shop Pro
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Photographer's website:
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