Collimation still not good, but did Jupiter and Mars imaging anyway
Posted: 27 May 2016
Open: Thursday, 26 May 2016, 1830 MST
Conditions: Clear, breezy
1921 MST: moved the dome onto the PZT. 1926 MST: sunset. Calm now. LX600 ON, StarLock OFF.
1928 MST: viewed Jupiter, 102X. The four Galilean Moons were visible. Using 271X some elongation of the moons was visible due to the still poor collimation, which I hoped to correct this night.
Slewed to Spica to began collimation work (again). Mounted the D7200 DSLR at prime focus + 2X PowerMate. I would use a magnified Live View to assist in the collimation. Spent over an hour trying to improve the collimation and checking it. FAIL. I could get a good collimation on one side of in-focus but not on the other side of in-focus. I gave up in frustration. May call Stellarvision in Tucson, who apparently has a "collimation service". I don't know if they make "observatory calls" though. I would prefer to not have to remove the 12" telescope from its mount.
In attempt to make things not a total loss on this night, I did some imaging of Jupiter and Mars with the D7200 DSLR. This prime focus, 1/20sec, ISO 1600, exposure shows four moons of Jupiter (and an overexposed planet):
This prime focus image of Jupiter is a stack of 1233 HD video frames, 1.3X crop factor, 60 fps, 1/400sec, ISO 1600:
2130 MST: did a 10 second test exposure of M53, but the stars were elongated and doubled. That confirmed the poor collimation even though the above image looks pretty good (with some editing).
This Mars image is a stack of 1230 HD video frames, 1.3X, 60 fps, 1/250sec, ISO 2500, using eyepiece projection at 271X:
The Mars image was downscaled about 50%. South is at the top, with some south polar shield clouds visible.
2203 MST: ended imaging through the poorly collimated 12" telescope. Once the telescope is back in collimation (soon?), the imaging tests this night should help with future Jupiter and Mars imaging.
Then viewed Mars and Saturn, 271X. The views were not very good.
2215 MST: LX600 OFF. Moved the dome off the PZT and back onto the observatory walls. Then began setting up for sky photography.
2305 MST: took this photo of Mars and Saturn in the constellation of Scorpius, f/3.5, 15 seconds, ISO 2500, FL 18mm, White Balance 4000K:
Mouseover or tap on image for labels
Close: Thursday, 26 May 2016, 2313 MST
Session Length: 4h 43m|
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