I shot this in March, but I couldn’t bring myself to post it until I had something to post from my replacement tube. I shot this with a Celestron RASA, an 11″ diameter scope with a blazing fast f/2.2 focal ratio. Sadly, it is also WAY too heavy for my Orion Atlas mount. I was lucky to get this picture the way the mount was straining under the weight of the equipment.
Anyway, M97, the Owl Nebula, on the left, is a planetary nebula, an expanding ball of gas which has been expelled from the outer layers of a star which is running out of fuel. Then that ball of gas is ionized by what remains of the star. M97 is a couple thousand light years away.
At the top right is M108, a galaxy around 42 million light years away. Our view of it is nearly edge on.
This picture was combined from the best (not sure how many) of around 44 exposures of 4 minutes each.
[By the way, the dashed line going from top left to bottom right is called a satellite flare, most often an Iridium flare. It happens because the satellite tumbles as it orbits, so it reflects more or less light towards any observer, depending on its position.]
Feb 14, 2016. OK, it is almost a year later, and I have been trying to get this target all week, same tube the 127 mm APO, focal length 660 mm, but this time with a new camera, a fully modified Canon 6D. Before this target last night, I shot M78, but I only had 2.5 hours of data, and I was fighting a 35% illuminated Moon, so it was pretty badly washed out. As a result, I had low hopes for this one, but it came out pretty nice. 40 Sub-exposures of 6 minutes each gave me a full 4 hours of data, and the Moon was down before I started shooting. Shot at 800 ISO.
April 12, 2015. Since this is an image I have wanted to do well for a long time, it was a natural choice for first light on a new 5 inch refractor with 952 mm focal length. [Actually around 660 mm focal length with the focal reducer]
Reworked this and am much happier with the results. It is 18 exposures of 10 minutes each at ISO 1600 and the tube’s f/7.5.
Had another go at this target at Alamo Lake State Park. I had a ton of problems, but, considering that this was taken with a 200mm lens and the one below was with a 610 mm telescope, it actually came out pretty darned good. Definitely did a better job on the companion galaxy near the right edge of the frame. 10 exposures of 300 seconds at f/2.8.
This was shot with a 6″ reflector (aprox. f/4) which I have been struggling with. It is made from 30 exposures of 300 seconds at ISO 1600. Shot on April 21, 2014. Located just off the handle of the Big Dipper, M101 is also known as the Pinwheel Galaxy.
My main mount is still not up to speed for long exposure tracking, but I decided to break out the Vixen Polarie and shoot the 35mm lens just so I could shoot something. I shot at wide open f/1.4, so there is some coma and blurring in the corners, but that stopped me from getting spikes on the stars and allowed 30 second exposures at ISO 400. I shot a total of 625 exposures, but a lot of that had extreme light pollution from the east horizon at the beginning of the shoot and the west horizon at the end. I got the best results by just stacking the best 240 from the middle of the night when Cassiopeia was almost directly overhead. You can easily see the Heart and Soul Nebulae, the PacMan Nebula, and the Double Cluster, as well as other deep space objects. Don’t just look at this one full screen, zoom it to full size or larger. Located in the outer edge of the Milky Way, the number of tiny stars in this frame is amazing!
Another low res image, a 1289 x 906 crop from a full frame. This one uses all 12 exposures of 300 seconds at ISO 1600 that I shot on the f/7.5, 127 mm Apo. There were other galaxies in the frame, but the full size image detracted from this pretty galaxy, which was the main target.
This is pretty low resolution, a 1220 x 907 crop from the middle of an 18 megapixel frame. It is also lacking in detail because I could only use the best 7 of 12 images at 300 seconds each At ISO 1600 on the f/7.5, 127 mm diameter apochromatic refractor. Shot without an LP filter.
Well, I spent a lot of time processing this image, but I spent most of it discovering that I could not torture it as hard as I normally do. The more I picked at it, the worse it got, and at last I would throw it away and start over. (Often, I will save, start over and eventually combine the previous try with the one I am working on.)
This is combined from the best 20 of 27 exposures of 360 seconds each at ISO 1600 on the 127 mm apochromatic refractor. Shot without an LP filter.
Revisited a portion of this target with the 127 mm f/7.5 tube. As expected, with nearly 5 times the focal length, I got a lot more detail. That I used 8 exposures of 1200 seconds each did not hurt either. Shot April 17, 2015.
This picture involved a lot of experimentation. I ended up using around 50 exposures of 300 seconds, at f/2.8, f/3.2, and f/4 And ISO of 1600, 3200 and 6400. Shot with the 200mm lens on March 27, 2014. There are a couple dozen galaxies in this picture, including elliptical galaxies M84 and M86 (the two brightest galaxies in the shot) and spiral galaxy M99 up at the top left.
Best viewed at full size. After the picture loads click to zoom in and click again to zoom back out. (Works in IE, not sure in other browsers.)
This was the third salvageable shot I took at Alamo lake on March 21. Too bad about all the problems I had, because this could have been a really awesome shot. If I view this full size (click the pic to see the larger image, then click that again when it finished loading so see it at full size of 5148 x 3420) I count 15 galaxies in this shot. Made from 13 exposures of 240 seconds at f/2.8.
This was another attempt March 21 at Alamo Lake. I am using a new camera which is not yet modified to pass hydrogen spectrum, so I lost a lot of the red in M82, but I got way more detail in M81. The top picture is the shot from Alamo Lake, and the second one is an attempt to combine that with the older, more colorful shot below. The new one is 13 exposures of 240 seconds at f/2.8.
This stack is composed of 23 shots of 300 seconds each at ISO 1600 through the 6″, f/4 reflector, selected from 50 shots taken starting around 10 pm on May 3, 2014.
OK, Think I’m getting somewhere on the new techniques now. At least the colors aren’t whacko.
Learned a new work flow…this was my first time through it. Hopefully I will get better with practice, but this is a small improvement, for sure.
As with terrestrial photography, there are infinite possibilities in post processing. I like this better, but it is from the same data as below.
The 400mm lens helps this shot a lot, as does fixing my white balance to get rid of the pesky red halos around the stars. I had some focus issues during the 3 nights I shot this, Oct. 22, 23 and 24, so one of those nights got tossed completely. This image is the best 113 exposures of 360 seconds each at f/5.6 and ISO 1600 out of a total of 156 taken.
It looks like I got all new equipment, but I just did some things differently. Clearly they worked, because this image is the result of 26 shots of 450 SECONDS each with the 200 mm lens at f/3.5 and ISO 1600.That is nearly triple the time I’ve been able to shoot lately.