This is a nice, though almost unremarkable, image of the gibbous moon. It is a mosaic
of 2 images (N and S hemispheres). The interesting aspects of this image are that
it was done without tracking (not much motion in very short exposures), and
it was taken at prime focus with the Meade ETX 105. All previous imaging with the
ETX had used a lesser but lighter camera, and eyepiece projection. This is the first
time I've gotten around to matching my better Canon SLR camara to the ETX. The result is
pretty good. Though I had forgotten that it's somewhat harder to focus the ETX than
my 6" scope, especially when the target is moving.
(1/125sec ISO 800, Meade ETX-105, Canon EOS Rebel XS; 2011/08/11)
A nice passage of the Moon in front of the Pleiades star cluster was marred by the presence
of thin to heavy clouds that rolled through just as the skies got dark. I took a lot of
pictures, but the gaps in the clouds never lasted more than 10 minutes (and were usually
much less). Most of my pictures were actually taken through the clouds, but this
resulted in fairly random exposures as I would occasionally adjust the shutter speed
to compensate for the rapidly and highly variable optical depth of the clouds.
The left image was taken though one of the last truly clear gaps in the clouds.
The limb of the Moon (featuring the crater Babbage in the cropped version)
is approaching Alcyone. The right image was in some respects
overexposed for the amount of clouds at that moment. However it does show three of
the Pleiades clearly (Merope, Electra, and the fainter star Celaeno). It also
shows the diffraction of the moonlight by the water droplets of the clouds.
I've boosted the saturation to make the colors more visible.
Judging from the info at Atmospheric
Optics, the water droplets in these clouds were about 125 μm in size.
(0.25sec ISO 200, 0.5sec ISO 400; 6"scope + 2x telextender, 2009/12/28)
This was a lucky shot. I hadn't been planing on photographing the Moon this evening, but
took a look anyways. The libration and light turned out to be excellent for viewing the Mare
Orientale. This large basin is usually very hard to see because of its location
at (and beyond) the limb of the Moon. Yet on this evening, the mare stood out as one
of the few features to show any relief at nearly full moon. I've never seen the
Mare Orientale so clearly before. (The linked, large-size image shows a better view.)
Several aspects of this feature have caught my attention.
[1] The mare impact basin seems to have 3 concentric rings of mountains.
[2] The terrain between the outer 2 rings seems relatively smooth.
[3] You can clearly see that the Mare is so large that it's not really flat, but
curves with the spherical lunar surface. This true for all the big impact basins,
but since they are seen face-on, I tend to think of them as being flat.
[4] Psychologically, I find it much easier to recognize the basin when it is
seen in the orientation shown here. If viewed at the tradition N = up orientation,
the structures seem less symmetric and more disorganized.
(3x1/60 sec ISO 1600 2x telextender, 10/3/09)
Just some large scale lunar mosaics.
The mountain and shadow on the edge of the Darwin Crater caught my eye.
Crüger is to the north. A hint of the Sirsalis Rille to the east.
(1x1/15sec exposures, ISO 400, 4x zoom, 5mm eyepiece, 6" scope; 2008/4/18)
For the February 20, 2008 lunar eclipse I mostly tried various telescopic images of the Moon.
|
|
|
|
Here's a montage of two shorter and two longer exposures during the
partial phase of the eclipse.
Telescopically, it was easy to see (photograph) several faint stars very near
the Moon during the total eclipse. Here the eclipsed Moon is about to occult
a double star (HIP 50370, 8.50 mag, companion is 9.81 mag and 4.5" away).
Unfortunately, the stars are slightly trailed during the 8-second exposure.
Here is a sequence showing the Moon
eclipsing the stars, and an alternate sequence
showing the stars setting over the limb of the moon (with a composite lunar
image generated using all the individual frames).
(12.5mm eyepiece, 6" telescope; 2008/01/20)
Mars and the Moon. Both are near opposition, but Mars is 250 times farther away.
A series of ~1/750 sec exposures. 6" telescope 25 mm eyepiece.
(2007/12/23 21:20-21:33)
The Moon is full of interesting detail when you look closely. Lately, I've
simply been taking a bunch of images (especially near the terminator, and
then sorting out the good bits later. This is one nicely lit frame, reduced in scale.
Hiding in the details are features like this: the Gambart C Dome.
The dome is the low round bump at the center of the frame. The Gambart C
crater is to its northeast, and Gambart B is to the southeast.
(2007/12/17)
I was lucky to be in Estes Park, CO for better view of this eclipse. In typical
Colorado fashion, the skies were cloudy (post-thunderstorms) at sunset but slowly
cleared overnight. The beginning of the eclipse was glimpsed through small
breaks in the clouds. At totality the skies were almost cloud free, though
this was partly an illusion caused by the lack of moonlight to illuminate those
clouds that did remain.
(Kodak ZX730 camera, 4x zoom, ISO 100, 1-sec exposures (montage) 1/250 sec-exposures (animation); 2007/08/28)
This image shows some of Janssen Rille (the thin crack in the floor of
the large crater at left) and the Rheita Valley (the much wider, interrupted trench
at the right center of this image). The linked uncropped image shows numerous
other features on the east side of the Moon.
(25mm eyepiece + Meade ETX-105; 2006/10/10)
This image shows Electra, one of the brighter stars in the Pleiades star cluster,
about 20 seconds before it was occulted by the Moon. It was sort of tricky to
be able to get a good image of the star without badly overexposing the moon.
The animated gif image
shows the full event with a sequence of images
at roughly 12 second intervals. (1/8sec ISO 100 4x zoom exposures,
25mm eyepiece + Meade ETX-105; 2006/10/10)
The Moon is more than one billion times closer to us than most stars seen in the night sky. Therefore when viewed from two different locations it exhibits a parallactic shift with respect to the distant background stars. (The stars seen here are Antares = α Sco, and τ and σ Sco.) The parallactic shift is proportional to the separation of the viewing locations, i.e. the baseline. The eyeball-to-eyeball baseline is wide enough to see parallax for objects near enough to grab (or hit with a thrown rock), but not enough for seeing the Moon's parallax. Using a wider baseline of about 1543km, this animation shows the Moon's parallax in a pair of simultaneous images. With the known baseline length, the parallax measured from the pictures can be used to calculate the distance to the Moon: 391473km. (This result turns out to be accurate to better than 3%.) Capturing these images was a joint effort with my friend Mark. The images are both composites 1/250sec and 2sec exposures at ISO 200 and 3x and 4x zoom, which were selected from sequences of image with exposures from 8sec to 1/1000sec. You can see his reductions of the same data at his website.
Below is a red-blue anaglyph version of the images.
Red(left eye)-blue(right eye) glasses will show a 3D effect, but it is
not very dramatic because of the lack of nearby background stars.
2006/08/05 03:00 UT.
A comparison of visible (left) and infrared (right) images of the Moon. I had hoped that the IR image might show some certain features differently than the visible image. However, there is little difference between the red channel of the visible image and the IR image. The quality of the IR image suffers a bit for several reasons: low sensitivity necessitated as much longer exposure time (1 sec vs 1/90 sec), and made focussing more difficult; the IR + red stacked filters produce internal reflections and scattered light.
A big Moon image, mosaicked from 13 1/15sec ISO 200 4x zoom images with a 25mm eyepiece and the Meade ETX-105. Light unsharp masking (50%, 1 pix radius). 2006/06/06 02:30 UT.
Yet another very thin crescent moon. Subtler than a sunset and easier on the eyes. Click on the image for the large-scale image. (1 sec, ISO 100, 4x zoom)
The original version of this image seems rather overexposed. Accidentally, I found that
inverting the image, as shown here, brings out very different detail. Most surprising to
me was the large number of evenly scattered small bright craters. These are distinctively
dark specks in the full-scale version of negative image.
This is a single 1/60sec ISO 80 exposure at 1.8x zoom
with a 40mm eyepiece and the Meade ETX-105 telescope.
A very light unsharp masking (2 pixels, 50%) was applied.
A higher magnification view of the Mare Humorum can be seen here.
(2006/04/09)
 |
 |
 |
 |
An animation of the best sequences of the evening is found here.
A cross-eyed stereo image appears here.
All images and the animated GIF are 3 sec ISO 200 exposures at 1x zoom with a 25mm eyepiece and the Meade ETX-105 telescope, except for the first still image, which is 6 sec at ISO 100. (2006/04/01)
The southwestern portion of the moon showing, Tycho (with rays) , Bailly (large crater on the limb),
and other features. This is an excerpt from a mosaic of several 1/90sec ISO 80 exposures at 4x zoom
with a 12.5mm eyepiece and the 6" telescope. A light unsharp masking was applied. (2006/01/12)
Langrenus is the large crater to the south. Mare Crisium is the circular sea, ringed
by mountains. Messier A and B (and their "comet tail" ray system) are visible too.
This is a 1/45sec ISO 100 4x zoom image taken with a 12.5mm eyepiece and a 6" newtonian telescope.
A moderate amount of sharpening (50%, 7 pix, 0 threshold) has been applied after the picture
was reduced in scale by a factor of 50%.
(2005/11/18 00:15 EST)
I don't really intend to keep photographing Aristarchus, but that's what happens
when I choose the same time of night to take pictures and have a limited range
of hour angle visible. The illumination here is almost exactly the same as in
my picture from March, below. This image is a mosaic
of 3 1/8sec ISO 200 4x zoom images taken with a 12.5mm eyepiece and a Meade ETX-105.
A moderate amount of sharpening has been applied.
(2005/11/12)
 |
 |
 |
 |
| The full moon on 2004 Nov. 26, 11 PM EST. This is a mosaic of 5 exposures (after conversion to grayscale), with a sixth low-resolution full moon image layered on top to provide the color. | The full moon on 2005 Jul. 21, 12:30 AM EDT. This is a single 1/90th sec exposure, ISO 80. The image was sharpened slightly, and the color was desaturated (the original was reddened by low elevation and hazy skies. |
 |
 |
Clouds prevented me from seeing the April 8th 2005 partial solar eclipse, but the next day was crystal clear. I hadn't thought ahead to shoot the Moon at this time, so when I happened to spot it just after sunset I had to hurry to grab my camera, telephoto lens, and a tripod before the Moon set. This one picture turned out nice and sharp. Click on the image at left for a medium-sized image of the full scene or here for the full-screen sized image. (1 sec, ISO 80, 4x2x zoom x telephoto lens)
The following day I was better prepared for taking some pictures telescopically. I was hoping to get some interesting details near the limb of the Moon. Bright twilight and relatively poor seeing at the low elevation makes for unspectacular results. Still, if you stare at the single frame image at left (Meade ETX-105 + 25mm eyepiece), you can faintly seen the lunar maria illuminated by earthshine. Click on the image to see a more greatly magnified (12.5 mm eyepiece) and shorter-exposure mosaic of 5 frames. Here is the full-size 5-frame mosaic. (1 sec, ISO 80, 4x2x zoom x telephoto lens)
The crater Aristarchus and surroundings. 1/3 sec. 6-inch telescope. 12.5mm eyepiece. 2005/03/21
19:48:29 EST.
The first quarter moon on 2005 Mar 15. The full size image is not particularly good. 6-inch telescope, 26mm eyepiece, 1/60th sec exposure at f/2.8, 5.5mm focal length (1.0x zoom), and ISO 80. The original image was rotated, down-sized, and cropped.
Theophilus is the prominent crater on the terminator on the west side of the Mare Nectaris.
The mountains along the east side of Mare Nectaris are the Pyrenees Mountains.
6-inch telescope, 6 mm eyepiece, 1/6th sec + 1/15th sec
exposure at f/4.8, 22mm focal length (4x zoom), and ISO 400.
The two pictures were balance for contrast, converted to grayscale, combined using a
"lighten" function, masked where the discontinuity of the vignetting looked bad,
and rescaled to a smaller size (about 25%).
The first quarter moon on 2005 Jan 17. This seems to be my best single-frame image of the moon to date, despite being slightly underexposed and perhaps vignetted at the northern end of the terminator. 6-inch telescope, 26mm eyepiece, 1/180th sec exposure at f/3.4, 8.2mm focal length (1.5x zoom), and ISO 100. The original image was rotated, down-sized, and cropped.
The large crater here is Albategnius. Klein is the smaller crater
within that is about 1/3 the size. 6-inch telescope, 12.5mm eyepiece, 1/90th sec
exposure at f/3.4, 22mm focal length (4x zoom), and ISO 400. The picture is cropped, but
no other adjustments were made.
The gibbous moon on 2004 Dec. 20, 9 PM EST. This is a mosaic of dozens of videos frames (small field of view) collected with a Meade electronic eyepiece. The Moon was drift scanned along 6 or 7 chords. Frames about 10 sec apart were selected from each scan to provide a fully covered mosaic with a fair amount of redundancy. After mosaicking the gamma was adjusted from 1 -> 1.5 in order to bring out fainter regions near the terminator. It was a cold night with fairly poor seeing. I used a green filter to try to reduce any chromatic effects.
More digital pictures: Dawn, November 9, 2004. (1/4 sec, ISO 80, 4x optical zoom;
and 1/8 sec, ISO 140, 1x optical zoom).
October 27, 2004 8:45 to 10:15 PM EDT at 15 minute intervals. 1/60th sec exposures on Kodak 400 HD film. 25mm eyepiece on 6" f/6 Newtonian reflector. No clock drive. Clouds moved in as totality set in. The sequence moves from right to left, as the Moon enters the Earth's Shadow.
Christmas Night 2003 there was a fair conjunction between the Moon and Venus. I think these are the best such pictures I've taken. I seemed to get better results out of the photos in the brighter twilight than later in darker skies. The linked page contains two large pictures.
This is a sequence of images from the total lunar eclipse of Nov. 8, 2003. The pictures are mostly 1/4 sec exposures taken every 10 minutes from 6:30 to 8:10 PM EST (200 ASA, 200mm telephoto lens, some editing of the contrast of the scanned prints). Clouds drifted by midway though the partial phase, and then thickened up entirely just after totality started. The exposures are good for the eclipsed portion of the Moon, a nice complement to my other sequence (below) which captures the uneclipsed portions.
Two nights before Hurricane Isabel hit the area, this was the waning gibbous moon rising.
The full Harvest Moon appeared near Mars on September 10, 2003 at about 12:15 AM EDT. The Moon picture turned out well enough. Click on the Moon for a larger scale picture.
The Moon one night from the backyard on September 6, 2003 (UT).
A mosaic of 3 images covers most of the crescent moon. (Sometime prior to November 2002.)
The crescent Moon and Venus on January 28, 2001.
A few days before the next lunar eclipse (on September 27, 1996) I tried to
practice taking Moon pictures though my 6-inch reflecting telescope.
I wanted to see what sort
of scale I could get, and whether I could use short enough exposure times that
tracking the Moon was unnecessary. The results are OK if you don't try looking for
too much detail. I suspect the pictures are a little blurry because I simply messed up
the focus, but it could be bad seeing, or the lack of tracking that made the pictures
blur. (Click once for the big picture, and again to turn up the magnification.)
This is a sequence (right to left) from the lunar eclipse of August 17, 1989. I had lost track
of the date, but checking past eclipses, this is the only one that would fit for the place
I recall taking these pictures in Rockville, MD. A long time after
I took these, I scanned the prints and merged them electronically. Not spectacular, but sort
of nice. It was a very dark eclipse as I recall.
Rick Arendt
January 2, 2010
