On Friday, 5/27/2022, my DS26cTEC + “new” 8 inch RASA telescope saw it’s first real use on my new backyard pier. I actually received my RASA telescope last year but other than testing it once, I just now started using it … so it is still “new” for me. RASA stands for Rowe-Ackermann Schmidt Astrograph and is a high precision very fast f/2 telescope made for astronomy cameras. “Fast” in this context means it can use very short exposures times. Your camera attaches to the top end of a RASA telescope (similar to using a Hyperstar lens on a regular telescope). The left picture below shows the camera mounted on the top end of the RASA, which is on my AVX mount. The right picture below shows the setup on my new backyard pier with cabling and the dew shield in place over the camera.
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Because the telescope is tailored for use with a camera, you cannot look through a RASA telescope with your eye – there is no place for an eyepiece to be inserted. Even though is not useable for visual viewing by looking through it with your eye, it is very useable for viewing using a video astronomy camera that “looks” through the telescope for you and displays what it sees in near real time on a monitor screen.
Pairing the f/2 RASA telescope with the Mallicam DS26cTEC video astronomy camera means it only takes 2 seconds to see on your screen your first image of an object you just slewed to, and with just a few stacked frames you can see a really nice image of the object. It is easy to zoom in from the full field of view image to a bigger image of the object while viewing. On the left below is the full field of view image. On the right of all the images is a digitally zoomed-in portion of the target object.
Pairing the f/2 RASA telescope with the Mallicam DS26cTEC video astronomy camera means it only takes 2 seconds to see on your screen your first image of an object you just slewed to, and with just a few stacked frames you can see a really nice image of the object. It is easy to zoom in from the full field of view image to a bigger image of the object while viewing. On the left below is the full field of view image. On the right of all the images is a digitally zoomed-in portion of the target object.
 Whirlpool Galaxy M51 - 1b 2s 100g 40-100h 30stk 7.92 magnitude 28 Mly |  |
As you can see, the DS26c+RASA produces a very wide field of view yet is capable of digitally zooming in on the image in real time to see some nice detail of the Whirlpool Galaxy (M51) using the DS26c bin 1 mode (bin 1 uses the native pixel resolution of the camera). The caption below the image identifies the object, camera settings, magnitude and target distance in light years (in this case 28 Million light years away). Here is what the camera settings mean:
1b : the basic bin 1 mode of the camera was used
2s : the exposure time is 2 seconds
100g : gain was set at 100
40-100h : the histogram was set to 40 on the left and 100 on the right
30stk : 30 images were stacked (2s x 30 = 60 seconds = 1 minute)
I live just north of Jackson, MS with Bortle 6 skies, it was 67 degrees, clear and no moon. The DS26TEC cooling was set at 32 degrees, and I did not use any darks and did not use a filter. All images are the actual camera image captures (with no post processing).
Here are some of the other objects I viewed the over the first two nights using my new RASA and pier…
1b : the basic bin 1 mode of the camera was used
2s : the exposure time is 2 seconds
100g : gain was set at 100
40-100h : the histogram was set to 40 on the left and 100 on the right
30stk : 30 images were stacked (2s x 30 = 60 seconds = 1 minute)
I live just north of Jackson, MS with Bortle 6 skies, it was 67 degrees, clear and no moon. The DS26TEC cooling was set at 32 degrees, and I did not use any darks and did not use a filter. All images are the actual camera image captures (with no post processing).
Here are some of the other objects I viewed the over the first two nights using my new RASA and pier…
 Bode’s Nebulae/Cigar Galaxy M81/M82 - 1b 2s 50g 50-200h 15stk 6.77/8.02 magnitude 12 Mly |  |
 Needle Galaxy NGC4565 - 1b 2s 100g 50-150h 25stk 9.08 magnitude 39 Mly |  |
 Globular Cluster in Serpens M5 - 1b 2s 100g 50-150h 20stk 5.65 magnitude 24kly |  |
 Spiral Galaxy in Canes Venatici M106 - 1b 2s 50-150h 100g 40stk 8.31 magnitude 25Mly |  |
I was initially viewing beside my telescope using my laptop on a table as shown at the beginning of this post. Later I ran an ethernet cable from my laptop on the table outside to inside my house and plugged it into my home network switch, enabling me to view from inside at my office desktop with a 32” curved monitor using Remote Desktop to control the mount and camera. Note that I was still using the MallincamSky software and Stellarium software running on my laptop next to the mount to control the camera and to slew to my target objects (with Remote Desktop my inside monitor, keyboard and mouse just acted as if they were directly attached to the laptop outside next to the mount). Here is a handheld phone picture of my desktop screen inside as I checked out a preliminary zoomed image of M64.
Below is the actual image I captured from the camera with improved settings …
 Black Eye Galaxy M64 - 1b 2s 100g 50stk 50-150h 8.38 magnitude 14Mly |  |
While I was using Remote Desktop inside, I used a Blink camera setup next to my telescope outside and activated a live view on my phone to watch the movement of my outside setup whenever I slewed to a new target. This being my first inside control of my new telescope and pier, I wanted to monitor the slew in real time. Everything ran smoothly and I had no cable issues. Here is a short video clip from the Blink camera.
I did try out 2x2 bin mode as well …
 Globular Cluster in Canes Venatici M3 - 2b 1s 50g 5stk 25-255h 6.19 magnitude 33kly |  |
I mainly chose to use camera settings during my first use that allowed me to quickly see my targets and watch a nice image appear on the screen and zoom in for the ahhh effect, and I wanted to see if it could be done at native bin 1 for maximum resolution. It worked. I plan to try out 2x2 bin some more with the RASA in the future.
I have decided I like my new pier, “new” RASA and the DS26cTEC combination whether I am outside next to the mount or using Remote Video Astronomy from inside.
I have decided I like my new pier, “new” RASA and the DS26cTEC combination whether I am outside next to the mount or using Remote Video Astronomy from inside.
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