Hi all, sorry for the basic question. I don't have any trouble finding the moon and was able to photograph it successfully once. My equipment is set up and I've set the mount to my latitude in Adelaide hills and pointing south using the compass on my mobile phone. But when I use the Goto feature on my app to say find the Jewel Box, it goes near but not on it, so I presume my mount is not pointing to true south or celestial south....not sure which one it's mean to be or how to set it considering everything I've been reading seems to be for finding the south using a polar mount which AM5 says is not needed. Any help is appreciated. I would really like to find the Jewel box cluster which is above my deck most nights, I believe it is just SE of Beta Crucis (Mimosa) in the Southern Cross. I can zoom in on Mimosa but can't find the Jewel Box with just moving my telescope.
I am not familiar with your mount or level of experience, but here are a few thoughts from a manual perspective.
Start by looking for the cluster using your lowest magnification eyepiece. The cluster is relatively narrow at 10 arcminutes across and may initially appear very small. Look for a very small ‘A’ shaped cluster of stars using low magnification and then zoom in (or attach the camera) from there.
It should not be too far away. It is around two degrees, or one to two fields of view from beta Crucis at low magnification. Attached is a photo with one-degree increments marked from beta Crucis.
As you say, the cluster is southeast of beta Crucis. However, depending on what star diagonal you have, the image may be inverted and the direction you need to move across the view may be different to expected. The movement you want is for the front end of the telescope to move down and left from beta Crucis (when viewing in the evening). For an SCT, this may be through moving down and right (rather then left) along the image.
Generally, a mount should be aligned to true north/south rather than magnetic north/south. The compass app may have a setting for true north. For the Adelaide Hills, the difference between the two is around 8 degrees east, which is a bearing of 172 degrees when using a compass set to magnetic north.
The compass on a mobile phone might not be very accurate. A proper magnetic compass may work better. Be sure to stand away from the metal in the telescope, mount and tripod which may interfere with the reading.
If your mount is placed in the same position in the backyard every time you observe or image , you can mark the ground ( hopefully either concrete, pavers or tiles and not grass ) with a permanent true south line.
If your ground is gravel or grass you could use some large pavers or tiles to sit your tripod down and still mark a true south line.
The attached method of finding True South using the Suns shadow is very accurate provided you take care and be as precise as you can with set up.
There are many other ways to find True south using technology but the Solar Noon method is quite simple in its method.
Also it’s probably worthwhile to use and learn a planetarium like Stellarium to get familiar with the night sky , again there are many other planetariums to use.
Stellarium is very popular as you can change real time and set it for any time during the night whilst having a cuppa and learn the night sky during the day.
Hi Arietty. If you have some binoculars just look in the general area and you will see the cluster. Then you will know where it is. Then use your RDF and hand controller to move your scope to the same area and you should find it in a low power eyepiece. If you have no binos you still should be able to pinpoint the clusters position using Stellarium and your RDF
Cheers, Richard
I see that you're using a Schmidt-Cassegrain Telescope (SCT) for visual observation. I had an 8-inch Celestron SCT in the 1990s, and I absolutely loved it.
With an SCT featuring a 2032mm focal length, achieving accurate polar alignment is crucial for successfully locating objects in the sky. Due to the narrow field of view, minor alignment errors can significantly impact GoTo accuracy, making it challenging to center targets efficiently. If the polar alignment is not precise, GoTo functionality may struggle to place objects within the field of view, requiring manual adjustments.
If you're using an iPhone, you can adjust the compass settings to display True North instead of Magnetic North, which may help refine alignment:
For my own setup, I use Polar Scope Align Pro (iPhone app) to achieve an initial alignment before attaching my telescope. Afterward, I perform precise polar alignment using my ASIair system and a dedicated camera. While ASIair may not be applicable in your case, ensuring your mount is closely aligned with the southern celestial pole will significantly improve tracking and object locating performance.
I see that you're using a Schmidt-Cassegrain Telescope (SCT) for visual observation. I had an 8-inch Celestron SCT in the 1990s, and I absolutely loved it.
With an SCT featuring a 2032mm focal length, achieving accurate polar alignment is crucial for successfully locating objects in the sky. Due to the narrow field of view, minor alignment errors can significantly impact GoTo accuracy, making it challenging to center targets efficiently. If the polar alignment is not precise, GoTo functionality may struggle to place objects within the field of view, requiring manual adjustments.
If you're using an iPhone, you can adjust the compass settings to display True North instead of Magnetic North, which may help refine alignment:
For my own setup, I use Polar Scope Align Pro (iPhone app) to achieve an initial alignment before attaching my telescope. Afterward, I perform precise polar alignment using my ASIair system and a dedicated camera. While ASIair may not be applicable in your case, ensuring your mount is closely aligned with the southern celestial pole will significantly improve tracking and object locating performance.
Do you have an astronomy club near you?
Clear Skies,
Christiaan
thanks Christiaan - I haven't bought ASIair because I dont' want to do astro-photography yet. the narrow field of view is an issue I'm sure as sometimes I can see an amazing array of stars, just have no idea where I'm looking as I can't get far enough back to visualise the space. I am in an Astronomy club and have been to meetings with great presentations but haven't been to a star party yet as many are cancelled before I can get there or on a weekend that I'm busy. I will go back to drawing board and try for a better polar alignment using the compass suggestions in this thread! Cheers and here's to clear skies - Lisa
Hi Arietty. If you have some binoculars just look in the general area and you will see the cluster. Then you will know where it is. Then use your RDF and hand controller to move your scope to the same area and you should find it in a low power eyepiece. If you have no binos you still should be able to pinpoint the clusters position using Stellarium and your RDF
Cheers, Richard
thanks Richard, Binos certainly helped tonight even though there is some cloud cover. I can just and so make the cluster out so here's hoping for a clearer sky this coming week! Lisa
I just checked the maths for your equipment - it will be around 3 fields of view away using your zoom eyepiece set to the lowest magnification.
Thanks. I'm not sure what that means (3 fields of view) but as soon as we get a clear night, I'll work it out and do you think I should use my 32mm eyepiece then swap out to my highest mag which is 6mm eyepiece or use the zoom eyepiece which goes from 24mm-8mm? TIA
If your mount is placed in the same position in the backyard every time you observe or image , you can mark the ground ( hopefully either concrete, pavers or tiles and not grass ) with a permanent true south line.
If your ground is gravel or grass you could use some large pavers or tiles to sit your tripod down and still mark a true south line.
The attached method of finding True South using the Suns shadow is very accurate provided you take care and be as precise as you can with set up.
There are many other ways to find True south using technology but the Solar Noon method is quite simple in its method.
Also it’s probably worthwhile to use and learn a planetarium like Stellarium to get familiar with the night sky , again there are many other planetariums to use.
Stellarium is very popular as you can change real time and set it for any time during the night whilst having a cuppa and learn the night sky during the day.
Wow, thanks Martin. Lots to read there. I used to use Stellarium but removed it and installed SkyView and SkyAtlast (the latter for the ASI mount). I seem to remember having trouble with Stellarium wanting to be callibrated or something all the time.
cheers and here's hoping for clear skies so I can have another go with all this advice. Lisa
Thanks. I'm not sure what that means (3 fields of view) but as soon as we get a clear night, I'll work it out and do you think I should use my 32mm eyepiece then swap out to my highest mag which is 6mm eyepiece or use the zoom eyepiece which goes from 24mm-8mm? TIA
HI l Lisa, use your 32mm eyepiece (lowest power), then maybe your zoom. 6mm is way too high power for the Jewel Box on your scope.
best of luck, Richard
I am not familiar with your mount or level of experience, but here are a few thoughts from a manual perspective.
Start by looking for the cluster using your lowest magnification eyepiece. The cluster is relatively narrow at 10 arcminutes across and may initially appear very small. Look for a very small ‘A’ shaped cluster of stars using low magnification and then zoom in (or attach the camera) from there.
It should not be too far away. It is around two degrees, or one to two fields of view from beta Crucis at low magnification. Attached is a photo with one-degree increments marked from beta Crucis.
As you say, the cluster is southeast of beta Crucis. However, depending on what star diagonal you have, the image may be inverted and the direction you need to move across the view may be different to expected. The movement you want is for the front end of the telescope to move down and left from beta Crucis (when viewing in the evening). For an SCT, this may be through moving down and right (rather then left) along the image.
Generally, a mount should be aligned to true north/south rather than magnetic north/south. The compass app may have a setting for true north. For the Adelaide Hills, the difference between the two is around 8 degrees east, which is a bearing of 172 degrees when using a compass set to magnetic north.
The compass on a mobile phone might not be very accurate. A proper magnetic compass may work better. Be sure to stand away from the metal in the telescope, mount and tripod which may interfere with the reading.
Keep at it. I am sure you will find it.
Great Pierre_C - thanks for the clarification and the image which is helpful with the field of view stuff. I'll definitely get a proper compass tomorrow. Using the hand control is a bit tricky - the joystick is so unpredictable and I don't think I get it to go slowly enough but I'll keep practicing. As you can tell I am a rank beginner and can't even tell if I should move left or right but I'll keep working on it! Lisa
I haven't bought ASIair because I dont' want to do astro-photography yet. the narrow field of view is an issue I'm sure as sometimes I can see an amazing array of stars, just have no idea where I'm looking as I can't get far enough back to visualise the space.
That's always the problem, you can only see just one bright star until you look through the eyepiece and then you can see thousands of the things despite them being invisible to the naked eye.
Are you In equatorial mode or alt/az? The am5 does both? If you are just doing visual the alt/az is what I would use. It will make your hand controller more intuitive too.
Quote:
Originally Posted by Arrietty
Great Pierre_C - thanks for the clarification and the image which is helpful with the field of view stuff. I'll definitely get a proper compass tomorrow. Using the hand control is a bit tricky - the joystick is so unpredictable and I don't think I get it to go slowly enough but I'll keep practicing. As you can tell I am a rank beginner and can't even tell if I should move left or right but I'll keep working on it! Lisa
Compasses and compass phone apps are not ideal for finding accurate True South , they are prone to calibration errors based on the surrounding magnetic fields in your location ) mainly from the type and composition of Iron in the regolith in your region.
A friend who use to hike a lot , gave me an expensive Silva compass ( with magnetic declination) which I used to try and find True South at both my observing and imaging locations.
After using the Solar Noon Shadow method at both locations , the Silva Compass was anywhere between 5 to 8 degrees out. Project that error up to the night sky and your a long long way from the Pole.
In fact, the Compass slightly gave variable results each time I used it. ( So did my iPhone )
Gave the Compass back to my friend.
My experience with compass’s and iPhones ………
Martin
PS: My Solar Noon Shadow lines are permanent marks and are accurate for at least the next 10 years.
Compasses and compass phone apps are not ideal for finding accurate True South , they are prone to calibration errors based on the surrounding magnetic fields in your location ) mainly from the type and composition of Iron in the regolith in your region.
A friend who use to hike a lot , gave me an expensive Silva compass ( with magnetic declination) which I used to try and find True South at both my observing and imaging locations.
After using the Solar Noon Shadow method at both locations , the Silva Compass was anywhere between 5 to 8 degrees out. Project that error up to the night sky and your a long long way from the Pole.
In fact, the Compass slightly gave variable results each time I used it. ( So did my iPhone )
Gave the Compass back to my friend.
My experience with compass’s and iPhones ………
Martin
PS: My Solar Noon Shadow lines are permanent marks and are accurate for at least the next 10 years.
Are you In equatorial mode or alt/az? The am5 does both? If you are just doing visual the alt/az is what I would use. It will make your hand controller more intuitive too.
I originally set it to Alt/Az but then someone said it didnt' need that so I think I put it to eq but not sure - I've fiddle around with it so much now! I will put it back to factory mode soon and start again.
That's always the problem, you can only see just one bright star until you look through the eyepiece and then you can see thousands of the things despite them being invisible to the naked eye.
Yes, that is exactly right! Some of them are so bright too and not visible even with binoculars.
Thanks everyone for your input. I did have a really clear sky last night and spent a lot of time on the moon. Got a very detailed photo using my mobile over the eyepiece. Was surprised what a good resolution it gave considering I couldn't use the phone adapter which holds the phone steady because I could not find the moon unless I moved it around. Anyway, then I spent a lot of time trying to locate the Jewel Box and think I did find it eventually but I can't be sure. It was just a bunch of bright stars but not the different colours I've read about so not sure if it was the Jewel box I found. Got a sore neck anyway trying to locate it through the RDF. I'm off to Brisbane tomorrow so will have another go when I get back to SA.
