Chris Howard's Blog, page 70
March 14, 2018
Here’s my final stacked and processed image of M42, the...
Here’s my final stacked and processed image of M42, the Orion Nebula (most of the thick clouds of hydrogen at the bottom), M43 De Mairan’s Nebula (spherical cloud in the middle), Sh2-279 Running Man Nebula (top). I shot the 17 frames that went into this image from my backyard, and each of those frames took 5 minutes to complete. The crazy thing is that each frame is a 300 second exposure that lets the camera count photons (a particle that represents of quantum of electromagnetic radiation) that have traveled a little more than 1300 years through space from the reflected starlight of a nebula to earth, then through our atmosphere to land on the camera’s sensor. That’s what astrophotography is all about: counting photons. http://SaltwaterWitch.com/astronomy
Snowed all day yesterday and it was still snowing at 5am this...
Snowed all day yesterday and it was still snowing at 5am this morning. With the wind and drifting it’s tough to say, but I’d guess 2 - 2 ½ feet. This is a shot of the backyard, and yes, that’s a standard 6 foot fence, with the snow halfway up.
March 12, 2018
First test shots of M42, the Orion Nebula, M43 De Mairan’s...
First test shots of M42, the Orion Nebula, M43 De Mairan’s Nebula, Sh2-279 Running Man with the ZWO ASI071MC cooled CMOS camera. No calibration frames, just 17 stacked 300 second light frames, with the sensor cooled to -10C. And last night was not very clear, scattered clouds, fairly poor seeing. I can’t wait to test things out with some really clear and dark skies. I will say, so far, with only a few hours of use, I’m impressed with this ZWO color camera. That doesn’t surprise me. ZWO makes a solid camera–I’ve been using an ASI120MM-S for several years, as my guide camera. It’s fast–USB 3, with a small but very sensitive monochrome sensor, and it just always works under any OS on a variety of hardware–Windows, Linux, MacOS. That’s what I meant–it shouldn’t surprise me that the ASO071MC (quite a bit more expensive and a far more capable camera) just works well. What did surprise me is how much this camera can pick up, bringing out some very faint nebulous areas. I know it has a very wide/high dynamic range. That’s one of the things I was looking for in an OSC camera. For this M42 test I used a Gain of 0 and Offset of 8, the minimum recommended by ZWO for long exposure times and HDR (high dynamic range). We’ll see how things go on the next clear night. I’d like to test out unity gain settings, and LRN (Lowest read noise) setting, which is high gain, high offset, used for short exposures. (William Optics GT-81 + 0.8x Field Flattener/Reducer f/4.7, ZWO ASI071MC cooled CMOS camera, iOptron CEM25P EQ mount, 30mm mini guide scope with ZWO ASI120S-MM guide cam, INDI/KStars/Ekos observatory control. Location: Stratham, New Hampshire, US. Bortle ~4).
March 11, 2018
March 11, 2018 - Setting up the William Optics GT81 tonight with...
March 11, 2018 - Setting up the William Optics GT81 tonight with my new ZWO ASI071MC camera. I’m also trying out–again–the 30mm apt/135mm fl guide scope with the ZWO ASI120MM-S, this time with the camera threaded directly to the scope, reducing the backfocus a few more millimeters. This will be my first time out with the new main camera, and I’ve been anxious to see what it can do for almost a week. The ASI071MC is a color CMOS camera with an impressive dynamic range, TEC cooling, 16MP APS-C sized Sony sensor with 4.8μ pixels. The idea is to have the new color camera compliment the Atik 414EX monochrome CCD I normally use. The Atik with the Nikon 180mm f/2.8 lens has almost the same field of view as the ASI071MC with the William Optics GT81. (The Atik + Pentax Takumar 200mm f/4 is even better). You can’t tell with the way I’ve configured the top dovetail rail and guidescope, but the plan is to be able to run both cameras simultaneously with similar FOV, one color, the other with narrowband filters, in some ways doubling my productivity. http://SaltwaterWitch.com/astronomy
March 10, 2018
humanoidhistory:Star Trek’s Nichelle Nichols with Apollo 12...
Star Trek’s Nichelle Nichols with Apollo 12 moonwalker Alan Bean at NASA’s Johnson Space Center in Texas, March 4, 1977.
If you know me, you know I’m a giant fan of The Culture...
If you know me, you know I’m a giant fan of The Culture books. So, I painted some Iain M. Banks fan art today–and I’m calling this “The Mind of the General Systems Vehicle, Just The Washing Instruction Chip In Life’s Rich Tapestry”. About four hours in ArtRage and PSCC, named after a Culture GSV from Banks’ last SF book, The Hydrogen Sonata. http://SaltwaterWitch.com
anudibranchaday:
Arguably one of the coolest looking nudibranchs...
Arguably one of the coolest looking nudibranchs is the Phyllodesmium iriomotense, an aeolid nudibranch native to Japan and Indonesia. It feeds on soft corals and gets to be about 2cm long. While it is small, it definitely seems like some alien one would find on an ice-planet!
