0.00
#...
·
 |
|---|
|
if i want to image an object tonight that i imaged last night ... how to i get my canon dslr camera to be rotated to the same angle as my previous night, aside from just dead reckoning? i think there's a way my asiair mini can help do this, but i cant find any tutorials on it. thanks for reading. |
1.20
#...
·
·
4
likes
|
|---|
| If you plate solve an image with the ASIair it provides the coordinates and the rotation angle. You could make a note of both those on the first night. On the second night you input the coordinates, slew the telescope and then plate solve again. You can then repeatedly adjust the rotation angle and plate solve until the angle is right. If you didn’t note down the coordinates and rotation on the first session you can get this info by uploading your image to various sites like Astrometry or Telescopius to platesolve. |
1.20
#...
·
·
4
likes
|
|---|
| If you have your picture from the night before still on the Asiair or the USB stick, you can navigate to the picture, hit solve and press goto. No need to enter coordinates. |
5.73
#...
·
·
2
likes
|
|---|
| Agreed with @andresch , and once your scope navigates to the center of the previous night's image, if necessary, a message will show on your screen informing you that the angle of the current framing needs to be adjusted. The text (at least on my screen) is garbled, but if you tap the center (different colored text), you will be shown both views and the amount CW or CCW you need to turn your camera to to align the current view to the previous night's image. Once you make an adjustment to your camera angle, you can refresh the screen to monitor your progress. I don't think I've ever gotten it closer than .2 degrees .... |
|
1.91
#...
·
·
4
likes
|
|---|
|
Here is a low-tech method for your consideration: Before you take your camera off the focuser, use a sharpie marker (I use the grey ones as they show up on black), and mark the position of your camera on both the camera adapter and the focuser flange.. When you come back for the second night, simply align the marks on the focuser and camera. If you want to get rid of the marks, I think rubbing alcohol works best. Works for me anyway. |
2.86
#...
·
·
1
like
|
|---|
|
I used to capture in Nebulosity, before i switched to NINA. In Nebulosity, you can load an image, place three fiducial markers on top of three prominent stars in your image, and then frame your life view to these fiducials. If you didnt touch the camera, rotation should still be perfect. This is only a digital version of Francois' marker approach, it allows zooming in, though. If i remember right, there is a free version of Nebulosity. |
8.04
#...
·
·
2
likes
|
|---|
|
APT (which will work with a DSLR) used to have a routine for repeat nights to mark stars. Hopefully it still does. if you take your camera off in between sessions that will be more problematic of course. Good tip above about rotation. l don’t use plate solving but do keep my camera in place. Generally l line up by eye looking at where stars are on my software reticule. It might be a fraction out but consider that to be a small “dither”. A small amount of edges cropping will be needed afterwards. Remember to take new flats if you remove your camera. |
1.51
#...
·
·
1
like
|
|---|
| Use the goto option mentioned earlier and take preview images where the stars are visible. Rotate according to how your images from the previous night were (check for stars in the corner of the image). This may take a couple of iterations before it works. |
|
0.00
#...
·
·
2
likes
|
|---|
|
I make a custom folder on the ASIair (when connected to PC) named “Previous Targets”. I then store a light frame from each target I’ve imaged. I label the saved image as the target and scope +/- teleconverter that I used. If I want to shoot the same target again, I go to “image manager” on Asiair, hit “go to” and it will plate solve and go directly to target. Then use the “frame” option to get your sensor orientation. I do keep a backup of the folder on my PC in the event ASIair decides to delete my folder (it hasn’t happened to date). |
5.38
#...
·
·
1
like
|
|---|
|
I use a digital level (like this one) to record the rotation of the camera. For instance, at the moment I am imaging M31 with an APS-C sensor and I have it rotated 12.5 degrees counterclockwise to allow the galaxy to span the widest dimensions of the sensor, from corner to corner. Before I mount the telescope, I sit it on a flat surface, zero the digital level to that surface, and then place it on the flash hotshoe of my DSLR. I rotate the camera until it reads 12.5 degrees on the level, and lock it in that position. For this to work on a dedicated astronomy camera, you'd need some sort of zero-reference for the level to sit on - perhaps some printing on the back of the camera, or one of these. But the digital level has been so helpful, and removes the need to platesolve and check. CS! |
6.05
#...
·
·
1
like
|
|---|
|
Plate Solving is the tool to achieve repeatable results. Weather it be a different night, different year, moving back onto a target after a meridian flip or a filter change. The secret is your imaging software and how you manage the data and target runs. if you loose a target run, No Big Deal, plate solve an old light frame of a target and paste that info into a new target and keep going. Specific ways to do this depending on the application you use. I us SGP and run 3 to 5 rig at once. Each rig has a NUC to run SGP and select a previous target run and a hardware profile from a list... Good Luck, CS Tim Ray |
0.90
#...
·
·
2
likes
|
|---|
|
With your ASIair (assuming your DSLR is compatible) if you touch the little star map in the bottom left corner of your screen, it will show a large star map with the rectangle of your camera on it. Along the border of the rectangle will be the rotation angle in degrees. Make a note of that during your imaging session so you can be sure to adjust your camera rotation the next night to match it. |
