Saturday, October 14, 2017

Close ups of the waxing gibbous moon

The horrid weather continues here, either rain, thunder and high wind, cloudy nights or nights murky like a bowl of milk were the norm for the past month. Then a hurricane came my way, then veered to the west knocking out the power as it went by. Fortunately, no damage resulted. It's finally starting to cool down and last night when I was observing with the Celestron I opted not to use the dew heater and chose to use the dew cap alone. Since skies were too poor to make driving to the airstrip worth the time and effort, I set up at home and concentrated on the Moon instead.
The 60 mile wide complex crater Copernicus was well positioned for imaging, so I made an effort to get plenty of video of it. The close up view was made with the use of my 2.8X University Optics Barlow lens between the camera and telescope. The wider area image was made with the camera alone at the telescope's prime focus. Because the sensor in the camera is very small, the camera sees the same field of view that a 5mm eyepiece would show through the same telescope. That is why I am using my film camera to take whole disk photos of the moon and Sun, it would take most of the night to take videos of the whole of the moon, then I would have to mosaic together the resulting still images. The video eyepiece is great for specific features on the moon through.

The odd color haloes visible in the video files are due to the Barlow lens I am using. Per advice from another amateur astronomer who is also a lunar and planetary imager, I just bought a 3X TeleVue Barlow lens. Then it'll be time to see what improvement in the sharpness of the views I am recording upgrading to a TeleVue Barlow lens offers. I plan to incrementally build up a set up that enables me to get high quality lunar and planetary imagery. A very good opposition of Mars is coming next year. Jupiter and Saturn will also be imaged as soon as they are back into a good position for imaging too. I'm also going to try for Mercury, Venus, Uranus and Neptune, even though they will be very tiny turquoise or ice blue orbs even with a 3X or stronger Barlow lens and superb seeing.
I noticed this field of craters as I was scanning the face of the moon with the Celestron, and thought it would make an interesting subject. Note the crater floors are still in darkness while the rims are sunlight, evidence of their great height above the surrounding plain.

The craters Messier and Messier-A were made by a pair of asteroids hitting the surface at the same time. Because they came in at a very shallow angle relative to the surface, they hurled jets of pulverized lunar rock ahead of them, forming the twin streaks extending from the craters. This feature is obvious even near full moon with a small telescope.

The ancient lunar highlands crater Ptolameus dominates the frame in this photo. Note the completely flat crater floor, other than the small impact crater in it, it's completely filled with hardened lava that welled up from below between three and four billion years ago. The crater to the left is Alphonsus, which is where the Ranger 9 lunar probe slammed into the moon at the end of its mission to take close up pictures of the moon. It's impact at 8,800 feet per second or nearly 6,000 mph excavated a crater over 40 feet across that was spotted by the Lunar Reconnaissance Orbiter. Right up to the moment it was destroyed on impact, it relayed ever sharper pictures of what was then a completely unknown lunar surface.

I re-imaged the Archimedes crater region and got better video than the last time. With that Registax yielded a much better image. I find that processing video and extracting a still image is tedious work, requiring a great deal of experimentation with the wavelet functions to get a good view. The effort however can and does pay off in amazing high resolution close ups of the Moon and planets. It is somewhere in this area the Luna 2 spacecraft crashed into the moon back in 1959.

This picture of the 2-day old moon was taken on Fujicolor 200 print film at prime focus with my Nikon F-3 and an exposure time of 1/15th of a second. Despite the low elevation, the moon displays great detail along the terminator.

A week later I imaged the moon again with the same camera and film after using the video eyepiece to take close ups. Here I used a shutter speed of 1/125th of a second.
Four days after that I imaged the 13-day old moon with the same camera and film, but I used a shutter speed of 1/250th of a second. I recently found a good cable release so use of the self timer was no longer needed. I did however use the mirror lock-up as before. After taking delivery of the 3X TeleVue Barlow, I plan to acquire a flip mirror to make finding and centering objects in the camera's tiny field of view easier, as well as a 2X TeleVue Barlow lens. It will be used for the times when less magnification is needed, but more than what I would get if I used the camera at prime focus. Then it will be time to get a better camera. The current camera has neither very good resolution or dynamic range. It is little more than a web camera repurposed into a video eyepiece.


Sunday, September 17, 2017

The 22-day old moon and first attempts at deep sky objects.

Two hurricanes have plowed into the Gulf Coast in the past three weeks, and even though they missed my area the weather has been abysmal for astronomy. My area was very fortunate to say the least, Irma could have easily came for us instead of Florida. When it wasn't raining, the skies were as milky as a bowl of milk. So when I came home from the night shift, and saw the clear skies overhead, I seized the chance to observe and take a few photos too.
I first photographed the 22-day old moon. After setting up the telescope, and getting the camera ready, I first set the clock drive to track at the lunar, not the sidereal rate. That ensured the moon stayed put in the camera's field of view as I took several exposures at shutter speeds from 1/125th to 1/15th of a second, using the mirror lock-up and self-timer to allow vibrations from touching the camera to die out. Then I refocused the telescope and repeated the sequence four more times. The result you see here is one of several successful shots I got on the same roll of film. As before Fujicolor 200 color print film was used, and the processed negatives were scanned with my Canon scanner and filmstrip adapter then processed with Photoshop.
After taking 20 photos of the moon, I decided to use the remaining frames to take test shots to answer two questions. One was how big would objects such as M-42 actually be on film, or a full frame sensor for a DSLR. The other was to see how well the EdgeHD 8-inch SCT would evenly illuminate a film frame or electronic sensor that large. I also wanted to see how film would work at F/10 on faint objects. I got those answers through these photos, which are trailed because the polar alignment was off and I do not yet have an auto-guider. If the control paddle's read out on the alignment is anywhere close to accurate, I was 15 arc-minutes off in altitude and 6 minute off in azimuth. Enough at 2,000mm of focal length to trail the image. The first shot is of the Double Cluster, and is a 5-minute unguided exposure. A surprising number of stars were recorded in this picture, even the colors came through well.

This photo is a 10-minute unguided exposure of the Orion nebula. The inner region is well exposed, and had I got the polar alignment were it needed to be, and used a focal reducer and auto-guider, I am sure I would have got at least a decent picture even through I took all three of the picture shown here from my light polluted driveway. Fujicolor 200 print film seems to work better on faint objects than I expected it would.
While neither of these long exposure photos are prize winners, they are a beginning since I never took any photos like them before. With better polar alignment and an auto-guider, I am sure I can get far better images than these in no time.

Saturday, September 9, 2017

Solar Eclipse Revisited And The Nearly Full Moon

Recently, I got the last of my photos of the 2017 eclipse developed, and I had a chance to try out the waist level finder for the Nikon out on the Sun and moon. The results seem very positive, focusing was easier with the magnifier built into it. It was also much easier on my neck since it allowed the camera itself to work like a star diagonal. I'm going to use it instead of the normal pentaprism from now on when I'm taking photos though the telescope.
This picture was taken at the height of the eclipse, using the same exposure of 1/500th of a second as the last photo on Fujicolor 200 print film. All the sunspot groups that were on the Sun's face were covered by the moon, leaving a featureless crescent before the moon began to move away from the Sun. Twenty minutes after that, clouds forced an end to observation of the eclipse and I began packing up the telescope for the trip home. Two eclipses are coming to the U.S. in 2023 and 2024. The first will be annular, which means the moon is not large enough to completely cover the Sun. Instead of the corona, a ring of exposed photosphere will surround the moon. The 2024 eclipse will be total. Both eclipses' paths of totality will cross into the U.S. in Texas then continue to the north and east until they reach the Atlantic Ocean. I am marking my calendars for both, since they pass over or near San Antonio TX, I can drive there in ten or twelve hours with my telescope and other gear.

The picture of the moon was taken on the same film with a shutter speed of 1/250th of a second through the same telescope. As before, I used the mirror lock-up and self-timer to suppress vibration and the vibration suppression pads as well. The waist level finder and it's built in magnifier enabled me to look for features along the terminator that allowed for critically sharp focus to be achieved. At the time the photo was taken, the moon was mere hours away from being full. This is valuable practice for the total lunar eclipse that is coming in January 2019, for which I will be perfectly placed, weather permitting. No doubt there will be occultations of bright stars or planets in the near future that can be photographed in the exact same way.

Friday, August 25, 2017

The 2017 Solar Eclipse

The day millions waited for years to come has arrived last Monday, and I was ready to observe and photograph the 2017 Solar Eclipse. While it was not total from my area, it was an 85 percent partial eclipse well worth the wait.
To take this photo, I used the same telescope, camera and film used for the whole disk pictures of the moon published here. Because I was photographing the Sun, an over the aperture solar filter was required. I considered opting for a glass filter, but instead bought a Baader safety film Mylar filter instead. It left the Sun with a bluish or violet cast but the image quality was excellent. The views are razor sharp and irregularities in the moon's limb were obvious at 64X through a 32mm Orion Optiluxe eyepiece and a 2-inch Highpoint mirror star diagonal. Even the photos show the rice like texture of the granulated photosphere of the Sun.
I shot a series of pictures with the mirror locked up, and the self timer used to eliminate vibration. Exposure times ranged from 1/2000th of a second to 1/125th of a second, with the best exposures being at 1/500th of a second. The sky darkened dramatically and the temperature fell noticeably. Shadows took on a peculiar sharp edge quality and though eclipse glasses the Sun was easy to see as a thin crescent.
I set up at a local school system's science education center, where the staff was video broadcasting the event and some staffers and students were enjoying the view between the photos I took. I mainly wanted to observe the eclipse visually, but I wanted to get a few photos too. Everyone enjoyed the experience and many came away with photos of their own.
I was able to watch the eclipse until about 20 minutes after the eclipse reached it's maximum for my area, before clouds moved in and threatened to douse the telescope in rain. I then dismantled the telescope and took the film to a local lab for immediate processing. I still have to look through the rest of the film and some Solar photos I took as a test the day before the eclipse. Once I scan and process them, they will be posted here.

Monday, August 21, 2017

The Waning Crescent Moon

Four days before the total solar eclipse that crossed my country from one side to the other, the first one to do that in 99 years, I came home from work and set up the Celestron to catch the rising waning crescent moon. After letting the telescope equalize its temperature with the incredibly hot and muggy night air and cleaning up from work, I first browsed some deep sky objects of the fall sky. Then I looked as the moon, and features such as the crater Aristarchus, Schroeter's Valley and Sinus Iridium. Then is was time to take photographs of the 25-day old waning crescent moon.
I used the same film, camera, and technique as the earlier photos, except I used much longer exposure times than I used for the lunar phases near full moon. I started at 1/60h of a second and went as long as two full seconds in an effort to see if I could record the Earthshine on the dark side. While I did get good shots of the sunlit portion of the Moon, apparently two seconds with Fujicolor 200 print film was not enough to clearly record the Earthshine, at least not at F/10. It seems the moon was too bright for it and I needed to expose the film much longer to record it, but a two second exposure blew out the sunlit portion of the moon completely. Even with the frame I scanned here, the moon's limb is bleached out.
I did use the lunar rate on the AVX mount, and it seems to track the moon fine for longer exposures I will be taking in the future. When the next total lunar eclipse comes along, I will be ready. The focusing screen paid big dividends in enabling a sharp focus to be achieved. With the last two frames of film, I took a couple of test exposures of the Double Cluster at F/10 to see how the film would respond to long exposures. A fair number of stars appeared in the second shot, but they were trailed because I forgot to switch back to the sidereal rate and I don't yet have an auto-guider to guide the mount. I'm going to get a focal reducer before I try taking any photos of deep sky objects through the 8-inch EdgeHD, or simply buy a 80mm APO and use that on the AVX mount. It was just a test anyway.
Today was a day I was long looking forward to, and that was the total solar eclipse that took place today. I set up the Celestron at a local school system's science center and when I was not giving folks a look at the deep partial eclipse as it happened, I took some photographs. The day before I photographed the Sun and the sunspot groups across its face. When I get the film back from the lab, I will post it here. It was despite the hot and humid weather, a wonderful time.

Saturday, August 19, 2017

The Twelve Day-Old Moon

The last two weeks were a period of almost nothing but thunder, lightning, strong wind, clouds and torrential rain, but one clear night came along where it was worth the time to set up the Celestron. After setting up and polar-aligning the mounting, it was time to do some visual observing and photography in the driveway. After observing the planets Jupiter and Saturn, and a number of bright deep sky objects, I turned the telescope to the moon. After looking at features of interest to me with a high power eyepiece, I removed the eyepiece and diagonal and replaced it with the Nikon F-3HP and T-Adapter to photograph the moon. At the time it was two days away from full, which ensured faint objects were washed out or invisible due to the moonlight flooding the sky.
As before, Fujicolor 200 color print film was used, and again the camera's mirror was locked up and the self-timer was used to eliminate vibration from the operation of the shutter. Vibration suppression pads under the feet of the tripod were also used. Because the moon was nearly full, I exposed a series of frames using shutter speeds from 1/500th of a second down to 1/15th of a second, which badly overexposed the film. The best negatives were exposed at 1/250th and 1/125th of a second, and after examining the film I scanned one of the negatives at 3,200dpi with my Canon flat-bed scanner which also can scan 35mm film as well. Final processing was done with Abobe Photo Shop, which consisted of minor adjustments to the brightness levels, light sharpening of the image and cropping. The D-screen I bought for the camera made focusing much easier than the stock K screen older Nikon cameras come with. As a result, all of the frames were at least acceptably sharp.

Wednesday, August 2, 2017

Three nights

Last weekend I was able to observe, and photograph the moon on three consecutive nights with the 8-inch Celestron Edge HD telescope at home on my driveway. As before I simply connected my Nikon F3HP camera body to the rear cell of the telescope with a "T-adapter" and "T-ring" for Nikon cameras. In so doing, I turned the telescope into a 2000mm F/10 telephoto lens. The film was again Fujicolor 200 color negative film and I exposed it with shutter speeds from 1/250th to 1/8th of a second. From examination of the processed film, it seems the best exposures were at 1/60th second or so. To suppress vibration that would otherwise blur the photos, I manually raised the camera's mirror that flips out of the way of the shutter before it operates and tripped the shutter using the self timer. Again, vibration suppression pads were used under the tripod's feet.
The result you see here is a montage of the three photos I took over three nights. I focused the telescope, exposed a series of frames with the mirror locked up, then unlocked the mirror and refocused the telescope before exposing another series of frames. I repeated this process until the entire roll was exposed. In this way, I maximized the chances of getting perfectly focused negatives. Before taking this pictures, I bought a replacement focusing screen more suited to this kind of work than the standard "K" type screen Nikon cameras such at the F-3 came with. I found a "D" type screen which is simply entirely an entirely fine matte screen without any micro-prism or split image array. It's made for very long focal length telephoto lenses and thus well suited to the Celestron since Nikon did make a 2,000mm mirror lens in the past. It did make getting exact focus easier but I think for dimmer objects I'll either need to buy a Beattie Intenscreen or find a DW-4 finder for my Nikon that magnifies the image by six times. For now, the focusing screen I bought will do.
After scanning a frame from each roll of film at a resolution of 3,200 dpi, I imported the files into Adobe Photoshop and created this montage after adjusting the brightness levels, color balance and lightly sharpening them. As you can see, the changes of illumination across the lunar surface are quite dramatic over three days.