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Astrophotography Procedure with Levenhuk Telescope and ToupTek Camera.
Telescope Setup:
1. Astrophotography is much easier when the telescope can track the object as it moves across the
sky. Thus a Goto Computerized mount or an RA motor drive attached to an equatorial mount is
very useful in that it can keep the telescope moving with the object to keep it in the field of view,
Then you can concentrate on working with the camera without having to keep the object in view
at the same time.
2. For astrophotography it is best if the tripod is set as low as possible. This reduces the amount of
vibration the scope will experience. With the scope this low it is uncomfortable to use visually
but when taking images you will actually look through an eyepiece very infrequently.
3. Make sure the mount is level. If the scope is not level your tracking will not work well enough for
imaging. Properly align the scope. If the scope is not aligned properly your tracking will not work
well enough for imaging. A polar alignment is used for equatorial mounts and the 2-Star
Alignment for computerized mounts. Consult the telescope User Manual for these alignment
procedures.
Camera Setup:
1. It is important to become familiar with the camera and ToupSky software before attempting any
real astrophotography.
2. Using your laptop or tablet make certain the ToupSky software is loaded and the camera driver is
working correctly. This workflow is written using ToupSky Version x64 Version 3.7.6914. The
following are the setting I prefer to use. You may use different parameters but these are what I
like. For details on the ToupSky software consult the Help option.
a. Resolution: 1280x960
b. Format: RGB
c. Gain: 10.00 (I prefer high gain fast exposures)
d. Video Mode: selected
e. Auto Exposure: not selected
f. Exposure Time: 25mS (We will change this as needed later)
g. Color Balance: Default (Color Balance will be achieved in post processing)
h. Color Adjust: Default (Color Adjust will be achieved in post processing)
i. Frame Rate: Read the directions in the software and adjust accordingly
j. Color/Gray: Color
k. Flip: Personal preference (This controls how thing move on the screen)
l. Bit Depth: 8 bits ( frame rate is less than 1 if 12 bits is selected)
3. Learn and master the camera controls and ToupSky basics before attempting astrophotography.
It is important to become proficient with the basic operations of your telescope, camera, and ToupSky
software before you attempt astrophotography. If you cannot successfully perform these basics your
imaging attempts will fail, you will become frustrated, and will probably give up.
The next step is to manage your expectation on what your images will look like. You have probably
searched the internet and saw wonderful images. Your images will not look like the images from the
Hubble Telescope! Online, most of the astrophotography tutorials you can find are from people using 14”
scopes and large; and their camera probably cost more than your entire system. But that is ok.
To get used to the eyepiece camera with the telescope, first view some objects in the daytime like wildlife
or a distant hillside. After you get used to the camera in the daytime, try taking some photos of the Moon.
This is the easiest nighttime object. Then try to photograph Venus, Jupiter and Saturn after you take some
good Moon photos. Working your way from bright to fainter objects is the best way to gain experience.
An example using this procedure includes images taken with a 4” Skymatic 105 GT MAK telescope and a
ToupTek GCMOS1200KPB camera. It was taken in the Midwest (not know for good seeing conditions)
on an average night from my driveway in a light polluted area. Jupiter and three of its moons can be seen.
Notice how well the bands and Great Red Spot can be observed.
Figure 1. Image of Jupiter with 4” Skymatic 105 GT MAK Telescope and GCMOS1200KPB Camera
Image Capture Using ToupSky:
The following assumes the scope is aligned properly, tracking well, and that your target (Jupiter in this
case) is nicely centered in the scope.
It is recommended that the eyepiece camera is connected to the telescope without the diagonal mirror.
The camera should slide easily into the visual back and using the thumb screws lock securely into place. I
place the TOUPCAM label on the left so it is readable. The first step is to see the observing target - no
small task. When you switch from the eyepiece to the camera you will more than likely see nothing but all
black on the camera screen. This is expected because the focal length of an ordinary eyepiece is different
from the eyepiece camera. Thus some additional focusing is needed after switching to the camera.
The best method to locate your target is to first raise the camera exposure to 500mS. This will make sure
there is enough exposure to see something. You should see a big bright “donut”. This is the unfocused
image. Ideally, you want the observed image to be in the center of the telescope’s field of view. Perform a
rough focus by turning the focus knob until the “donut” becomes a circle and then make it as small as
possible. Next center this circle using the scope controls. In the photo shown below, the first image shown
has a relatively large field of view (FOV). This large FOV makes finding and keeping the target in view
rather easy.
Now we must obtain correct exposure and fine focus. The following snapshot was obtained using a 7mS
exposure. Notice how small the target is and that not much detail is available.
Figure 2. Original Snapshot of Jupiter with 7 mS Exposure and Wide FOV.
I used a 7mS exposure for this example. Your exposure may differ due to the seeing conditions. Trial and
error on what exposure works best for you is the only real method to get good images. The settings stated
here are only to get you started. Now notice that this snapshot looks nothing like the image you had in
mind when you bought your equipment. Don’t worry though because we will show you how to improve
the image in post processing with RegiStax, the free software for aligning, stacking and processing
images. To process an image RegiStax needs a video file. You can download Registax from their website
at http://www.astronomie.be/registax/.
To create a video of your image, press the ToupSky record button, give your video a name, save the video
to a location of your choice, make sure you save the file in the avi format, and set the Time Limit to 1
minute. This will give you about a 900 frame (15 FPS times 60 seconds) avi file which takes a little over
3 GB on your hard drive. Yes, astrophotography is very hard drive intensive. Once post-processed, your
image will look like this.
Figure 3. Image of Jupiter with 7 mS Exposure and Wide FOV Enhanced by RegiStax.
Notice the emergence of detail in the bands, no Red Spot but better that the snapshot. The problem is we
do not have enough magnification. The target does not occupy enough pixels on the image. To increase
the magnification we only need to add a Barlow lens. Barlow lenses increase the magnification of the
target image. A 2x Barlow yields an image twice as large, a 3x Barlow yields an image three times as
large, etc.
Now let’s add a 2x Barlow lens. Before adding the Barlow lens center the target in the image. When you
add the 2x Barlow lens the image is magnified by 2 but the FOV is then cut in half. The brightness of the
target will also be cut in half. Thus when you add the Barlow lens you must again find your target. First
increase your exposure to 500mS. Hopefully the “donut” is still there. If it is, follow the rough and fine
focus process followed earlier. For this magnification I use an exposure of 25mS. When changing from 1x
to 2x the FOV is still large enough that keeping the target centered is still relatively simple.
If you lose the image from your view you may have to go back to visual with an eyepiece, locate and re-
center your target and then switch back to the camera. The better you become at keeping your target in
your FOV the easier astrophotography becomes. Practice is the only way to get this experience. At some
point you will lose target lock and get frustrated. Practice makes perfect. Here are the 2x snapshot and
post processed images.
Figure 4. Snapshot of Jupiter with 25 mS Exposure and 2X Barlow Lens.
Figure 5. Image of Jupiter with 25 mS Exposure and 2X Barlow Lens Enhanced by RegiStax.
The post-processed image clearly shows more detail in the cloud bands. We can now also see three
Galilean moons. The Great Red Spot is starting to come into view near the closest moon but we need
more magnification to bring out the details. In my arsenal I have a 3X and two 2X Barlow lenses. Using
them separately or by combining them I have the following possibilities:
1. 2x 25mS
2. 3x 40mS
3. 4x stacking both the 2x 95mS
4. 6x stacking one 2x and the 3x 220mS
Note that each increasing magnification makes it harder to keep the target within the FOV. The above
also shows the exposure time I used. For the 6x the frame rate drops low enough that I used 2 minutes for
the Time Limit. Here are the post processed images at 3x, 4x, and 6x.
Figure 6. Jupiter with 40 mS Exposure and 3X Barlow Lens Enhanced by RegiStax.
Figure 7. Jupiter with 95 mS Exposure and two 2X Barlow Lens Enhanced by RegiStax.
We are starting to get too much magnification for this scope. The black smudge is some dirt somewhere
on the optics (not an asteroid strike). This dirt is in all the images but due to the increasing magnification
it is now visible. With even more magnification; black smudge in now two distinct dots.
Figure 8. Jupiter with 220 mS Exposure, Two 2X and One 3X Barlow Lens Enhanced by RegiStax.
Post Processing Using RegiStax:
The purpose of this section is to quickly introduce you to RegiStax. You can find information about
RegiStax online. It has no instruction manual and all the tutorials I have found all start by the person
stating that they are not an expert and everything they know they have found out by trial and error. I am
no different. I do not pretend to understand everything going on inside RegiStax. What is contained here
is what I have found to work for me. You will develop your own style. This is nothing more than a
reference point to get you started. I will be using RegiStax version 6.1.0.8 it can be downloaded for free.
The majority of the settings I use are the default setting. If you change some settings RegiStax will work
drastically different. Once I did something, what it was I am not sure, but to restore the program to a
known state I uninstalled and just reloaded RegiStax.
I will use the 3x example for demonstration purpose. The same techniques were used to make all the post
processed images presented here. Also, none of the images present here were meticulously work to
become a final finished product.
The highlights of the work flow are:
1. Alignment: This accounts for movement of the image from frame to frame.
2. Limit: This allows that only the best frames are used for the final product.
3. Stacking: This uses these best frames to one improved frame.
4. Wavelet: This sharpens the details.
Here is my RegiStax workflow.
1. Load your avi file into RegiStax by selecting the video file. Once loaded you will see frame 1 in
the preview window. I prefer to start my processing in the middle of the frame list. Because this
avi files contains almost 900 frames I go to frame 400 (control located at the lower left of the
program). Then scroll around a few frames up and down to find a good local frame. A frame that
has good detail.
2. In the Set Alignment Parameters box change the Minimum distance between to 20. Press the “Set
Alignments” button near the top left. This will place a series of red dots on your image. These are
points the program will use to align your frames. I try to get anywhere from 15 to 50 alignment
points.
3. Now press the “Align” button. This may take some time, a progress bar is located at the bottom
left.
4. Next select Best Frames % and set the value to 50. This will use only the best half of your frames.
5. Press the “Limit” button. Yellow circles with green lines will appear on your image preview.
6. Press “Stack” and wait for the process to complete.
7. Select the Wavelet tab. Here is where things really happen.
8. Select the RGB Balance from the Function button collection. Press Auto Balance. This will cause
the color of your image to improve.
9. Select the Histogram button. Move the right slider to the base of the histogram on the right. Do
not move the left slider. Press the stretch button.
10. Now we manipulate the Wavelet control on the left hand side. There are 6 layers. Uncheck layers
5 and 6. We will use layers 1, 2, 3, and 4.
a. Set layer 1 to: Denoise 0.05 Sharpen 0.200 Preview 80
b. Set layer 2 to: Denoise 0.03 Sharpen 0.200 Preview 80
c. Set layer 3 to: Denoise 0.01 Sharpen 0.200 Preview 80
d. Set layer 3 to: Denoise 0.00 Sharpen 0.300 Preview 80
11. Select Flip and Rotate from the function buttons. Flip both X and Y. This will put Jupiter in the
actual orientation as seen from earth. This assumes that you had the camera installed in the scope
correctly.
12. Following this process with my avi file would give you an image that looks like the photo below
with good detail, three moons and the Great Red Spot visible.
Figure 9. Final Image of Jupiter with 40 mS Exposure and 3X Barlow Lens Enhanced by RegiStax.
You are now on your way. Just play with the controls, see what they do, and come up with your own
techniques.
Clear skies.
Schieber Telescopes
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