clear sky chart

Job 9:9

Job 9:9-10
9 He is the Maker of the Bear and Orion,
the Pleiades and the constellations of the south.
10 He performs wonders that cannot be fathomed,
miracles that cannot be counted.
NIV

Saturday, April 28, 2012

Messier 5

Since the moon is now out, I sort of gave up on NGC4565 for now and instead concentrated on some globular clusters.  The first set of images I did not have the telescope polar aligned properly.  I was in a bit of a hurry, and I ended up with streaking stars.  Since I got that focusing mask, I've found alignment is more critical, as poor focusing hides other imperfections.

Also, I learned something new about the stacker, and the settings I've been using.  My images have been coming out on the bright side, and it was very difficult getting rid of the noise.  I was limited by noise as to how much I could stretch the histogram to bring out faint detail.  The trick is to save the image without applying any settings that were made in the stacker...or do not modify the brightness curve.  My images show the spike to the left of the histogram curve in the stacker.

The images come out really dark when brought up in photoshop.  A very aggressive stretch will bring up the detail without increasing the noise as much as if the brightness was increased in the stacker.  When I was able to stretch the histogram to the point where the noise started to creep in, I was able to get about 10 times as many stars as before, as you can see in this image...


I also removed what noise remained, which was easy being there was so much less noise using Noel Carboni's Astronomy Tools v1.6.  A little bit of unsharp masking brought out a few more stars, then increased the star color saturation using the above toolset brought out a little more color in the stars.

Tuesday, April 24, 2012

Messier 3

Thought I'd try a different sort of object tonight.  It was probably just as well, as clouds began to move in while I was imaging a 2nd object.  I learned that you do not need near as much exposure time to photograph a globular cluster.  I can see little difference between 1 and 6 frames.  I did stack 6 frames and I'll place this image here.  Globular clusters look like they would be a very easy beginner's target, as this one came out real nice, and was not at all difficult to photograph.



This is the 6 frame stack. The frames were 120 seconds, and the final image enhanced some in photoshop and cropped to enlarge the cluster somewhat.

Here is a single frame....


The single frame shows the core better, whereas the stacked image shows the outer stars better.  Perhaps this would be a good image to do multiple layers?

Saturday, April 21, 2012

The Markarian's Chain

On 4/18/12 I had to work late, so I brought the telescope and found that my office had darker skies than home.  I took the opportunity of photographing the Markarian's Chain in Virgo.  Astrometry.net says there are 17 galaxies in this field of view, and all but one was captured.  I'm guessing IC3303 was too dim to be captured with the exposure I used.

This image is an unguided series of 12 frames at iso1600 and 3 minutes in length.


All of the galaxies are rather small, which does not surprise me, considering they're 60 million light years away.  This is a very dense field of galaxies.

A list of galaxies shown in this image can be found at http://www.flickr.com/photos/32416606@N05/7092530347/

Also of note, I had just acquired a Bahtinov focusing mask just in time for me to image this group of objects.  It really does take the guesswork out of focusing, which I have had some problems with in past images.  It can be difficult to tell if you are focused until you take a couple of long exposure images and see a bright star with a "hole" in the center.  This mask makes it much easier to determine if you are in focus.

I also purchased an integrated barlow / T-ring, which I used once while I was on site, but being I was unguided, the stars streaked a little more than I had liked.  It is going to work however when I use the autoguider.

I also took a few frames of the Needle Galaxy, NGC4565 in Coma Berenices.  There isn't near enough exposure time for this object, as I only took 6 frames at 3 min each...

This is a cropped image.  I did take 1 single frame of this object using the barlow, and I believe it is going to work out nicely, but without guiding, I didnt continue photographing this object after the 1 frame.  This image is without the barlow, and I had run out of time, as my primary target was the Markarian's Chain.

I will be revisiting this object again, as it is relatively large, and although it is quite narrow, I was able to capture the central dust lane.  Looking forward to using the barlow on this object and guiding the scope for some longer exposures.

Tuesday, April 17, 2012

Another M-51 from 4/16

Although it didn't look like it was going to clear up, it actually, did, and was able to get a halfway decent shot of M51, the Whirlpool Galaxy.

I chose the Whirlpool galaxy because it was bright, large and also pretty high in the sky.  It is a favorite of mine to photograph because it is so bright that thin clouds will not obscure it too much when trying to photograph deep sky.   Transparency was not great, but was good enough to capture the thin, dim spiral arm that connects the 2 galaxies.

M51 is located in the constellation Canes Venatici, and is just south of the 2 eastmost stars in the Big Dipper.  The galaxy is roughly 25 million light years distant.    It is estimated to contain about 160 billion times the mass of our sun and is about 85,000 light years in diameter.  It was discovered by Charles Messier in 1773, and he catalogued it Messier 51.

Charles Messier was a "comet hunter", and he created his catalog of  objects which could be mistaken for comets.  His objects which he cataloged  consists mainly of galaxies, compact star clusters and small nebulae.  His catalog consisted of 103 objects, but a few were added by colleagues later, and ended up being a list of 110 objects.  They are popular targets for amateur astronomers.

This is what I was able to see in a 6 inch newtonian, using a Canon Rebel T3 camera...


This is a cropped image, as the full frame had a fair amount of gradient noise due to flats that over-corrected the image.


Sunday, April 8, 2012

Saturn, 4/8

After imaging M106 last night, I noticed Saturn rising above the trees to the south.  I believe this planet is approaching opposition, as the rings appear bright.  I havent checked to see when opposition occurs (or occured), as it does hit the horizon right around sundown.

I took 2 videos using the QC Pro 4000 webcam.  The first is a low res 240X320, 30 fps.


This is the original size image.  Because Saturn is so much dimmer than the other planets, I could not stack both barlows right away, although in the next image, I did stack them both, but dropped the frame rate down to 5 fps to get a longer individual exposure time per frame, and I believe it is my best Saturn so far.


This is a cropped 640X480 frame.  if you look closely, I believe the C-ring is visible, and I'm not entirely certain, but I also think I can see the Encle division on the left side.  it is a thin dark line barely visible on the outer edge of the outermost ring.

M106

Last week I received an Astronomik clip in CLS filter for my Canon Rebel.  I got it in hopes it will help with the streetlight across the street as well as other local light pollution.  I must say, it does take away the muddy brown tint in my images, but it also shifts the color balance on the blue side.  However, that can be taken care of by increasing the red slightly in the camera.

Unfortunately the moon has been out, so I really couldnt give it a good test yet.  Last night however, I was able to shoot for about 30 minutes or so without the moon interfering.   It was enough to notice the absence of the brown gradient.  My target was M106.  Because the data was rather lacking because I only shot about 45 minutes at iso 400 (5 minute subs), the faint detail really isnt visible.  What I am impressed with is the detail in the fainter, tiny galaxies in the image.  I am especially impressed with how NGC4217 came out.  Thats the little galaxy on the top of this image.


Monday, April 2, 2012

Crater Bullialdus

Imaged several areas of the moon with the 6 inch polar mounted scope using the 3X barlow and QC4000.  First image that I processed was one of Bullialdus crater & vicinity.  This is a 61 km dia crater.  Notice the valleys on the left..  Those are Rimae Hippalus.  Resolution seems to be pretty good in this image.