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In what direction is the universe expanding?

bileduct

Coach
Messages
17,832
I’ve got a skywatcher ax gti which is a tracking mount and using a software called stellarmate os via reasoberry pi. Totally automated telescope, if I want to take pictures of say the Orion nebular the telescope will be guided and using the stars it will align itself to take pictures while tracking the object. But focusing is the key ..

Altitude-Azimuth mounts (which the AZ GTI is) are good for looking at stuff with the naked eye and doing planetary imaging (which is really stills taken from video) but they are shithouse for long exposure starfield/nebula photography. You really want a equatorial mount like the Skywatcher EQx series.

Focus isn't your primary issue in the telescope image. The amount of drift that is evident in your one second exposure is pretty high. What's the focal length of the telescope? I'm assuming it's a Newt reflector given the diffraction spikes. Do you polar align?
 
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Generalzod

Immortal
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31,971
Altitude-Azimuth mounts (which the AZ GTI is) are good for looking at stuff with the naked eye and doing planetary imaging (which is really stills taken from video) but they are shithouse for long exposure starfield/nebula photography. You really want a equatorial mount like the Skywatcher EQx series.

Focus isn't your primary issue in the telescope image. The amount of drift that is evident in your one second exposure is pretty high. What's the focal length of the telescope? I'm assuming it's a Newt reflector given the diffraction spikes. Do you polar align?
My Skywatcher evolux 62ED 400 mm focal length…

I used this guys instruction to set up my telescope
 

bileduct

Coach
Messages
17,832
My Skywatcher evolux 62ED 400 mm focal length…

I used this guys instruction to set up my telescope

So it's a refractor. What the f**k is generating the diffraction spikes?

As far as that build goes, I have a few issues with it. As I've already said, Alt-Az mounts are just not good for starfield stuff without a wedge, especially so if you are stacking as part of a processing workflow. EQs are far more preferable. This dude should know this, but I didn't hear him mention it once or even suggest using a wedge.

Also, and maybe this isn't a huge deal at a low focal length, but guide scopes are pretty much a necessity for long exposure photography unless you have a $15K mount with encoders built in. All mounts will only track accurately to within a range of arc seconds and suffer from periodic error and backlash. Both can be effectively tuned out to improve accuracy, but requires a second camera (at the very least, usually a second telescope as well) to track the position of the stars and send minute adjustments to the mount.

For a simple one telescope/camera setup you probably would have been better off with one of these -> https://skywatcheraustralia.com.au/product/star-adventurer-pro-2i-pack/
 

Generalzod

Immortal
Messages
31,971
So it's a refractor. What the f**k is generating the diffraction spikes?

As far as that build goes, I have a few issues with it. As I've already said, Alt-Az mounts are just not good for starfield stuff without a wedge, especially so if you are stacking as part of a processing workflow. EQs are far more preferable. This dude should know this, but I didn't hear him mention it once or even suggest using a wedge.

Also, and maybe this isn't a huge deal at a low focal length, but guide scopes are pretty much a necessity for long exposure photography unless you have a $15K mount with encoders built in. All mounts will only track accurately to within a range of arc seconds and suffer from periodic error and backlash. Both can be effectively tuned out to improve accuracy, but requires a second camera (at the very least, usually a second telescope as well) to track the position of the stars and send minute adjustments to the mount.

For a simple one telescope/camera setup you probably would have been better off with one of these -> https://skywatcheraustralia.com.au/product/star-adventurer-pro-2i-pack/
I tested it via my bedroom window through the flyscreen that gave it that effect…I was told that you can use flyscreen to help you focus on stars, kinda like bahtinov mask
 

bileduct

Coach
Messages
17,832
I tested it via my bedroom window through the flyscreen that gave it that effect…

Ahh, yes, that would do it.

I was told that you can use flyscreen to help you focus on stars, kinda like bahtinov mask

That doesn't sound right. A Bahtinov mask will produce three diffraction spikes in a very specific arrangement on roughly the same plane, and as you get to perfect focus they'll be spaced equally apart. I don't see how you could get that same effect with only two spikes on planes at right angles to each other. Just get a mask dude, they're pretty cheap.
 

Generalzod

Immortal
Messages
31,971
Ahh, yes, that would do it.



That doesn't sound right. A Bahtinov mask will produce three diffraction spikes in a very specific arrangement on roughly the same plane, and as you get to perfect focus they'll be spaced equally apart. I don't see how you could get that same effect with only two spikes on planes at right angles to each other. Just get a mask dude, they're pretty cheap.
It’s all just new to me, so it’s just hit and miss at the moment, later on when I get little experience I can turn the mount I have into eq One. I live close to the Sutherland Astronomical Society there Observatory is @ Grays Point .they offer every year a 2 week courses on Astronomy and astrophotography but it was all booked out this year. Thank you bileduct for your advise, it’s not the most easiest hobby to get into but it's a challenging one. I wanted to get the Vaonis Vespera which is just an automated telescope but when I saw the price I decided to build my own telescope….
Here is my telescope

1661635163817.jpeg
 
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bileduct

Coach
Messages
17,832
It’s all just new to me, so it’s just hit and miss at the moment, later on when I get little experience I can turn the mount I have into eq One. I live close to the Sutherland Astronomical Society there Observatory is @ Grays Point .they offer every year a 2 week courses on Astronomy and astrophotography but it was all booked out this year. Thank you bileduct for your advise, it’s not the most easiest hobby to get into but it's a challenging one. I wanted to get the Vaonis Vespera which is just an automated telescope but when I saw the price I decided to build my own telescope….
Here is my telescope

View attachment 65474

I am not a fan of all-in-one solutions so I would personally steer clear of the Vaonis products.

From what I have read Skywatcher have updated the firmware on the AZ-GTI so you can modify it and turn it into a EQ mount. Here's a good guide on how to do it:


You'll need to get a wedge (I would get the Williams Optics one) and a counterweight, and you'll need to learn how to polar align.
 

bileduct

Coach
Messages
17,832
@Generalzod Just as an FYI, I'm about 5 years and $25K into this hobby so feel free to shoot me any questions. I run a ES 127 CF triplet refractor on EQ8-R PRO have a fair amount of experience with Sequence Generator Pro, PixInsight, autoguiding/PHD2. My scope is completely automated, from focusing to imaging. I set up a sequence in SGP and press start, it'll move to that object, focus, track and image that object for however long you want it to, do automated meridian flips, change filters, dither, etc. Everything connects to a USB hub attached to the scope and then I run a long USB cable into the house to control it all from indoors.

This is my rig on my old mount (AZ-EQ6 GT), haven't used my new one much lately because of the shitty weather.

1R9A2820.jpg
 

Generalzod

Immortal
Messages
31,971
@Generalzod Just as an FYI, I'm about 5 years and $25K into this hobby so feel free to shoot me any questions. I run a ES 127 CF triplet refractor on EQ8-R PRO have a fair amount of experience with Sequence Generator Pro, PixInsight, autoguiding/PHD2. My scope is completely automated, from focusing to imaging. I set up a sequence in SGP and press start, it'll move to that object, focus, track and image that object for however long you want it to, do automated meridian flips, change filters, dither, etc. Everything connects to a USB hub attached to the scope and then I run a long USB cable into the house to control it all from indoors.

This is my rig on my old mount (AZ-EQ6 GT), haven't used my new one much lately because of the shitty weather.

View attachment 65513
That’s awesome setup , the way you spoke to me I had a fair idea you knew what you where talking about, I took your advise and bought
Myself bahtinov mask from eBay it was only $6.
thank you for your help if I need any help I will definitely give you pm…have you setup your own YouTube channel?
 

bileduct

Coach
Messages
17,832
That’s awesome setup , the way you spoke to me I had a fair idea you knew what you where talking about, I took your advise and bought
Myself bahtinov mask from eBay it was only $6.
thank you for your help if I need any help I will definitely give you pm…have you setup your own YouTube channel?

If you send me a PM also notify me in a thread. I think I am banned from sending PMs at the moment, maybe because I run an AdBlocker or I harassed someone... lol.

I don't have a Youtube channel but there are a few that I follow with dudes doing very similar stuff to me:


Chuck's ES 127 CF rig is very similar to mine (same camera, same primary and guide scope, same filter wheel, etc) except my mount and filters are better.

This is the last image I took... Haven't done much in the last year or two because laziness and weather is really shit at the moment.

64992588_10156571855792123_6963631713402486784_o.jpg
 

bileduct

Coach
Messages
17,832
One other thing...

This hobby can be expensive as f**k so it's easy to be put off by the price tags on the better equipment.

But there are two things you should always keep in mind:

1) You get what you pay for.
2) Unless you are buying absolute junk, the stuff you are buying will retain its value. Cameras not so much, but telescopes don't just suddenly lose 90% of their value. The ES 127 CF I bought 5 years ago is worth exactly as much today, and I could easily resell it for around 90% of the as-new price. Same goes with mounts.
 

Generalzod

Immortal
Messages
31,971
One other thing...

This hobby can be expensive as f**k so it's easy to be put off by the price tags on the better equipment.

But there are two things you should always keep in mind:

1) You get what you pay for.
2) Unless you are buying absolute junk, the stuff you are buying will retain its value. Cameras not so much, but telescopes don't just suddenly lose 90% of their value. The ES 127 CF I bought 5 years ago is worth exactly as much today, and I could easily resell it for around 90% of the as-new price. Same goes with mounts.
Yeah when I walked in to Bintel down at Glebe I was amazed as to how to much some of the the high end mounts cost. It even took around 3 months to get my little skywatcher mount....Over all my spend was about $2000, Zwo Camera ASI485MC, Mount, Telescope, and raspberry PI and Stellarmate OS. Actually my wife dreads that if I get better at the more money I will spend on it....she wants a new Kitchen lol
 
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Messages
3,832
@Generalzod Just as an FYI, I'm about 5 years and $25K into this hobby so feel free to shoot me any questions. I run a ES 127 CF triplet refractor on EQ8-R PRO have a fair amount of experience with Sequence Generator Pro, PixInsight, autoguiding/PHD2. My scope is completely automated, from focusing to imaging. I set up a sequence in SGP and press start, it'll move to that object, focus, track and image that object for however long you want it to, do automated meridian flips, change filters, dither, etc. Everything connects to a USB hub attached to the scope and then I run a long USB cable into the house to control it all from indoors.

This is my rig on my old mount (AZ-EQ6 GT), haven't used my new one much lately because of the shitty weather.

View attachment 65513
Does it take off and land alright?
 
Messages
3,832
Here's my take on the original question.

Imagine you have a perfectly spherical but flat balloon and you start to inflate it up.

It will expand in all directions equally and perfectly. That includes the second Big Bang if the balloon is blown up too far or.....

.....if some arsehole sticks a pin in it. Then that will be called the Big Deflation.

Just say the universe will become a black hole the size of our galaxy.

I know I watch too much science fiction. I've been addicted to it since my early teens.
 
Messages
15,386
It’s not a complete “we don’t know”. It’s “we know this much, but we don’t claim to know everything”. That’s very different to religion which usually claims that god is eternal and created everything.

One of the most important things about science is that it openly acknowledges that there are limits to how much we know.
I suppose that’s a point worth considering.

But is it better to a sad scientist than a happy Christian? I’m not sure.

At any rate, Im certainly happier to see resources poured into astronomy and exploration instead of military stuff.

Why are bothering going back to the moon when we could send more gear out to Saturn etc?
 
Messages
15,386
Here's my take on the original question.

Imagine you have a perfectly spherical but flat balloon and you start to inflate it up.

It will expand in all directions equally and perfectly. That includes the second Big Bang if the balloon is blown up too far or.....

.....if some arsehole sticks a pin in it. Then that will be called the Big Deflation.

Just say the universe will become a black hole the size of our galaxy.

I know I watch too much science fiction. I've been addicted to it since my early teens.
That’s not bad, but in order to have the flat balloon, there must be something surrounding it?

This is a good episode of old sci if you are interested:

4D4E0865-5FA6-42F2-AB73-53531A6F8148.jpeg
Source: Google trailers

Old mate is illegally using a radio thing to speak to alien lad and alien lad he’s not supposed be using his equipment either.

They discuss all kinds of interesting things.

No doubt they have borrowed some of the lads equipment featured here for the transmission.

Anyway, I was going to post it up for @Everlovin' Antichrist as he’s got the good mind and would enjoy the story which I think is well written.
 
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Messages
15,386
If you send me a PM also notify me in a thread. I think I am banned from sending PMs at the moment, maybe because I run an AdBlocker or I harassed someone... lol.

I don't have a Youtube channel but there are a few that I follow with dudes doing very similar stuff to me:


Chuck's ES 127 CF rig is very similar to mine (same camera, same primary and guide scope, same filter wheel, etc) except my mount and filters are better.

This is the last image I took... Haven't done much in the last year or two because laziness and weather is really shit at the moment.

View attachment 65518
That is f**king amazing, thanks for posting it.

I can make out claw things holding what I’ll call the “star bear”

I’ll show it to the kids tomorrow.

It should be framed. It’s like something from Hubble or the new one.
 
Messages
3,832
This is a good episode of old sci if you are interested:

View attachment 65590
Source: Google trailers

Old mate is illegally using a radio thing to speak to alien lad and alien lad he’s not supposed be using his equipment either.

They discuss all kinds of interesting things.

No doubt they have borrowed some of the lads equipment featured here for the transmission.
Don't worry Phantom. I've watched it many times including the original TV broadcast in late 1960s.

I've got a valuable hard drive with complete seasons of the following:-

Twilight Zone - Rod Serling's 156 episodes in b/w, the colour series that came out in the 1980s plus the handful of movies.

The Outer Limits - the original b/w episodes plus the coloured seven seasons from the 1990s.

Journey to the Unknown, Out of the Unknown and a bunch of stuff I just can't remember along with 100 odd hardcore and classic science fiction over the years.

You can stick your Star Trek, Star Wars, Babylon 5, etc. Because it's set in space, doesn't mean it qualifies as science fiction. Don't worry, I've seen them too but I'm a purist.
 
Messages
15,386
Don't worry Phantom. I've watched it many times including the original TV broadcast in late 1960s.

I've got a valuable hard drive with complete seasons of the following:-

Twilight Zone - Rod Serling's 156 episodes in b/w, the colour series that came out in the 1980s plus the handful of movies.

The Outer Limits - the original b/w episodes plus the coloured seven seasons from the 1990s.

Journey to the Unknown, Out of the Unknown and a bunch of stuff I just can't remember along with 100 odd hardcore and classic science fiction over the years.

You can stick your Star Trek, Star Wars, Babylon 5, etc. Because it's set in space, doesn't mean it qualifies as science fiction. Don't worry, I've seen them too but I'm a purist.
I remember that scene from Battlestar Galactica, the two female pilots heading out in a suicide mission to blow up the aliens. Certain death.

And in their final chat, one of them admits how she prefers autumn over all other seasons. It was a wonderful scene, slow paced, very sad.

I found out later that that the series won an Emmy for writing. On the tiny bit I watched, that was great, but I was still surprised.

it’s not the first show that springs to mind as quality.

Our old sci fi etc is infinitely better, more creative and enchanting.

I havent watched regular tv for years except the footy.
 
Messages
3,832
Our old sci fi etc is infinitely better, more creative and enchanting.
This. My favourite old school si fi movies would include The Day The Earth Stood Still, The Monolith Monsters, Invasion of the Body Snatchers, The Day The Earth Caught Fire and the ultra classic Forbidden Planet.

None of those movies had ridiculous car chases, fist fights or gunfights. They were thought provoking at the least, brilliant at the best.

Some later stuff is good as well. Event Horizon, Prometheus, Sunshine and the rarely mentioned deep and dark New Zealand made The Quiet Earth.
 
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