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.

Thursday, June 27, 2013

Narrowband Imaging the Crescent Nebula

Received my Hydrogen Alpha filter yesterday and we got lucky and had a couple hours of reasonably clear sky.  Although I didnt get as many exposures as I'd liked, my first real attempt at narrowband imaging was a success.  I imaged 2 objects - the Ring Nebula (M57) and NGC 6888, the Crescent Nebula in Cygnus.  The Ha frames that I took of the ring were washed out possibly due to clouds, but the Crescent came out just fine.  

I have never before gotten this much detail on this object before.  In the past, I was able to capture the bright outline with a tiny amount of  the inner nebula.

The above image consists of only 25 minutes of H Alpha and 25 minutes of O3.  Ha was mapped to red, Oiii mapped to green and blue.  I used the Ha stack as the luminance.  This was done with my light polluted backyard, and the Oiii was taken during the last full, supermoon.

Saturday, June 22, 2013

Narrowband Imaging

When I bought the G3 at Cherry Springs, I also bought an Oiii filter.  I wanted a Ha filter, but he didnt have any.  I ended up ordering one from Orion last week.

I figured theres no reason to wait for the Ha to come in to start taking narrowband images.  The moon was shining brightly, on its way to become the supermoon which is to occur tonight.  I took this image on 6/19/13 of M97, the Owl Nebula through the O3 filter.

There is some nice detail in this image.  Planetary nebulae are perfect targets for this wavelength filter. 

There is very little Oiii emission in the Crescent Nebula, as seen here...

Note that these were taken under a bright moon.

I'm really looking forward to imaging the crescent with the Ha filter when it arrives.

Sunday, June 16, 2013

M63 LRGB with the Starshoot G3

Finally, I had a good clear night and had enough time to image something properly with the Starshoot G3.  This time, I thought I would shoot a galaxy, and I chose M63 because it is a tightly wrapped spiral with a lot of fine detail.  Although this object would fare better using the 8 inch, being I'm still learning how to use this camera, I used the 6 inch.  The 8 inch's field of view with this camera is substantially smaller, and I really didnt want to mess this up with tracking and framing problems.

The 6" still showed quite a bit of detail.  I might have done a little better with more, shorter exposures, as the core is blown out.  However, I got the fainter extreme outer regions nicely with these 5 minute subs.

This was my first processing attempt.   These images are much more difficult to process.  I do believe however, that this camera is the way to go for smaller objects.

This next image was restacked, and reprocessed.  I took 20 dark frames and was able to go a little deeper.

I may have lost a little detail in this one, but I like the color better, and I got a little more of the outer regions of the galaxy.  I cannot figure out why the images are flipped vertically.  I didnt flip them, but I noticed in Fits Liberator, some of the frames were flipped and some were not.  I dont recall the exact processing workflow I used when producing these, so it might have something to do with the original fits files.

Tuesday, June 11, 2013

M57 Color using the Orion Starshoot G3

Last night, 6/10/13 we had a short period of clear sky, so I set up the 6" Celestron Newtonian and attached the Starshoot G3 and imaged until the clouds blew in.  This is the first color image so far which I was able to take with the new camera.  The image consists of 5 frames each, through blue and red filters.  I did not have time for a set of green exposures, so I used the "Synthesize Green from Red and Blue" tool in Noel Carboni's Astronomy Tools.

I still have to work on these images.  Just like with the dslr, when I began imaging with it, the images werent great.  Although the ring looks nice, I think theres a bit too much blue, as all of  the stars are blue.  Once I get clear skies long enough to image something using all 3 colors, I think the images should improve.

The camera appears to do a decent job, really.  The stars are smaller than they would be using the dslr, especially on small objects.  I am happy with the resolution, even though the max resolution is on the order of 752 X 582 pixels. 

Cherry Springs Star Party 2013

I attended the Cherry Springs Star Party 6/6 - 6/9/13.  Actually arrived Tuesday night, 2 days before the start of the star party.  Tuesday had the best skies of all of the evenings I was there.  Wednesday night, clouds rolled in, and it rained all the way thru Friday.  Saturday night the sky was clear again, but the humidity caused a very heavy dew to form.

While I was there, I bought my first real CCD, an Orion Starshoot G3.  I actually wanted a small chip for smaller objects.  Although I tried it out Saturday night, and was cut short due to the extreme moisture, I was able to shoot the Ring Nebula thru a red filter.  I only shot 5 frames, and I was shocked as to how quiet the image was.  Although the image is monochrome, the detail was quite good.

All images were shot with the Orion 8", f/5.  This image of M57 were shot with the Starshoot G3 thru a red filter.  Exposure length was 180 seconds.  This was shot on Saturday night, 6/9/13.

The Tuesday night images were all shot with the unmodified T3, as I left the power supply at home for the 300D.

M101, an object that I have problems with at home due to the light pollution, came out much better when I was able to use 5 minute, iso-1600 frames.

Messier 4.  The following star clusters are too low in the southern sky for me to image at home, so I took advantage of the dark sky and low horizon to capture a few of the Messier clusters in Scorpius and Sagittarius.  This is 6 - 60 sec exposures at iso 1600.

After capturing M4, I went over to M6.  This is only a stack of half a dozen 1 minute exposures.

 M7 is right near M6, so I thought I'd get it next.  4 - 60 sec frames, iso-1600.

Lastly, I shot M22.  This consists of a dozen 1 minute frames, also at iso-1600.

Saturday, June 1, 2013

Messier 51

This is not the first time I've imaged this one, but it is the first time I was able to image this deep.  Last year, 2 minute subs were my limit.  Now I can shoot 2.5 times in frame duration, and it certainly makes a big difference.

Here is 50 minutes worth of exposures:

And here is the above data plus data taken the next day. - Total of 22, 5 minute frames.

Notice the dimmer areas show up better.

I've noticed that the longer each frame is, the more detail, and the dimmer detail is captured.  The number of frames makes a difference, but not nearly as much as the exposure length.  These experiments should assist me when I begin shooting exposures at Cherry Springs next week.  Lets hope for clear skies.  As of right now, the best they are calling for is partly cloudy.

One more image, using both days but cropped in such a way to enlarge the galaxy:

This image appears to show more detail in the body of the galaxy, but the noise is more apparent in the fainter areas.