Good one.
Off topic: I was thinking of asking, what collimation tool do you use?
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Thank you @vijay ! I do collimation using a collimation cap and a piece of white paper(A4 sheet)
Link : How to Collimate a Telescope - Orion Telescopes and Binoculars - YouTube
Oh, I do the same thing too. I always wonder if I have to get a Cheshire.
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@vijay, I wouldn’t say that is really necessary as far as you collimate when you have decent amount of light as Cheshire also depends on light to collimate. However, a collimation cap doesn’t need direct light, you can use it in areas with dim light as well. However, there are a few issues that you need to keep in mind when you opt for a Cheshire or even lasers. They are,
- Cost - Cheshire is atleast 4 or 5 times dearer and lasers are atleast 10 times.
- Tools own collimation - if you drop them badly, it happens for many time to time, the cross hairs and laser will go out of alignment. So, you would have to first collimate the tool itself, before you collimate the telescope.
If you really that desperate to have an enhanced collimation tool, then I’d suggest the concentre eyepieces which works on the same principle as the collimation caps but helps identify the center very easily.
With any tool, the assumed and actual center may not necessarily be the same depending on whether you use the screws to hold the tool or compression caps to hold it in place etc. So, I’d suggest that you rotate the tool in the focuser tube to pick out any defects.
The other test post collimation I’d suggest you do is to pick a bright star and then focus in and out all the way to see how the blurred image intrafocus both at past and pre focus is if they are sharp at both, it’s good otherwise, there could be spherical aberration and if it is oblong and switches from one side to other in pre and past focus point, then your primary could be pinched and might need some adjustments etc.
But, I’d strongly suggest that you stay with the time tested tool, the humble collimation cap.
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The Moon’s Southern Hemisphere
This image visualizes the scale of a small spacecraft (Chandrayaan 3) against the moon’s surface.
Credit: @into..the..cosmos [Instagram Acc]
Details:
- Orion XT8 Dob
- 2x barlow lens
- Zwo asi 120m-cs
Software:
- Sharpcap
- PIPP
- Registax
- Lightroom
This actually show why it’s not possible to photograph small spacecrafts and landers relative to moon.
[Note : Only the background image is mine and all other were taken from low moon orbit spacecrafts]
Hardware:
Orion XT8 dobsonian
Zwo ASI 120mcs
Specs :
20-30 frames of moon at 1200mm focal length
Software:
PowerPoint (stitching frames)
Registax
Snapseed
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This is beautiful. Inspiring that it is hand tracking!!!
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