The "No EQ" DSO Challenge!

[happy-kat]

Before I installed 64 bit W10 I ran StarTools on XP 32bit so only had 3GB of ram. The trick is make sure your workflow always starts with crop then bin. It won't be fast but I found it rarely crashes. I use the same PC just I now have 6GB ram with W10 64 bit.

[Manners2020]

It is a pity  I liked the results  on a youtube video I was watching. I'll try again.

[Manners2020]

I've added another 4gb  since I tried it last. I'll try that crop then bin first.

[Manners2020]

So its 8gb now. Windows 8 though.

[happy-kat]

Windows 8 64 bit I hope.

[Manners2020]

I'll have to check on that.

[happy-kat]

If it's not 64 bit it's still RAM throttled to 4GB (in practice it's less).

[Manners2020]

So if its 32 my 8gb ram would be 4gb effectively?

[happy-kat]

Yes the 32 bit technology can't use more even if more is in the PC which is why for my same PC that I was running XP on I chose to buy another hard disc (I had space for installing another one) and put on it W10 64 bit, I use my bios to switch boot environment. 

[Manners2020]

So just managed to get in front of pc. It is 64 bit with an added 4gb of ram now bringing it up to 8 but I have a processor  which is only  2.00ghz.  In your opinion is that enough for startools?

[SteveNickolls]

Hi,

The advice on the StarTools site is-http://www.startools.org/downloads/technical-faq/minimum-specs seems RAM dependent rather than CPU, you will just have to be more patient with a slower CPU as ST's processes the data less quickly. ?  A SSD will help run things more speedily too.

I normally 35% bin images as the first step after downloading the file to process to reduce file size. My PC runs an original i5 processor (2.67 GHz with 4 threads) having 8 Gb RAM and a standard 7200rpm Hdd.

Best to just try your machine out and see how well it performs to your liking.

Good luck using ST's it's a good programme.

Best Regards,
Steve

[The Admiral]

8 hours ago, Manners2020 said:

In your opinion is that enough for startools?

The simple answer to that is to try it. Startools trial version is fully functioning apart from saving.

Ian

[Manners2020]

Tried it last night and it works, not too slow either. Thanks everyone. 

[nm1213]

Hi,

 

What an incredible thread to have stumbled on!  I’m inspired by the wonderful images and dedication to no EQ imaging.  I thought I was the only crazy person to attempt this because of my somewhat unique situation.  I live in Singapore, which means I have to deal with the following:

- Heavy light pollution.

- Terrible weather, which means clear skies are very rare.

- No access to a car (look up how much cars cost here), so have to walk over 1.5km on foot to the observing site.

- Not able to see Polaris (1 degree north of the equator) so either have to drift align or use Celestron’s All Star Polar Align.

 

I ended up with a C6 SCT, hyperstar, ASI 385 cooled camera, and an SE mount.  This worked well with Sharpcap live stacking.  However, I would have to crop a lot of the borders due to rotation gradients. I also suspect the hyperstar added a lot of weight and caused the SE mount to struggle.  

I then bought an AVX.  This works fine with the all star polar align routine.  However, it’s not as easy to setup, and pushing the AVX and other gear on a trolley over 1.5km gets tiring.  

I now have a third rig… Skywatcher AZ-GTI, lightweight Sirui tripod (folds down to 34cm or just over a foot), Nikon 180mm 2.8 lens, and the same ZWO ASI 385 camera.  This is super-portable and I can carry everything in a backpack.  However, I’m now thinking of something else… 

What if I put a field rotator into the mix?  I won’t be able to use the Nikon lens (focal distance is too short). However, optec and I went back and forth for a while and figured we could do it with a Canon lens (200mm 2.8, or 300mm f4), pyxis 2 inch rotator, and some custom machining.  This would weigh about 2.4kg which is well within mount specs of 5kg, while also being compact enough.  Alternatively, I can probably use a Borg 55FL OTA reduced to f3.6 (https://www.firstlightoptics.com/borg-55fl-telescopes/borg-55fl-f36-astrograph-set-a.html) with a Pyxis LE rotator and not need any custom part fabrication (I still need to see if this is possible).  

The rotator gets position info from the mount via ASCOM and adjusts the rate of rotation depending on which area of the sky you’re looking at. So now I’ll have a compact, fast (f2.8), light (2.4kg) alt-az imaging platform that I can go beyond 20-30 seconds per exposure.  However, will this work un-guided?  How far can I push the AZ-GTI mount without guiding?  I don’t think it’s possible to guide in alt-az.  The goal is to get 45 seconds at 200mm focal length (at f2.8). Doable, or would it be a waste of money to add a rotator?

Thanks!

N.

[happy-kat]

Welcome, great to read your story.

The az-gti can be used with the synscan pro application and this gives the choice of EQ mode on start up. Use a wedge with the az-gti head and add a balance weight bar. I'll add a link to show you.

https://stargazerslounge.com/topic/299015-skywatcher-gti-mount/?page=2&tab=comments#comment-3423738

Edited August 13, 2018 by happy-kat

[nm1213]

7 minutes ago, happy-kat said:

Welcome, great to read your story.

The az-gti can be used with the synscan pro application and this gives the choice of EQ mode on start up. Use a wedge with the az-gti head and add a balance weight bar. I'll add a link to show you.

https://stargazerslounge.com/topic/299015-skywatcher-gti-mount/?page=2&tab=comments#comment-3423738

Hi, Thanks for the suggestion.  I'll certainly get the EQ wedge for when I'm travelling and able to see Polaris.  I can't polar align easily from Singapore... especially since I need to pack up after each session and can't leave the rig out.

[happy-kat]

Unless you are aiming for 45 seconds regardless of where pointing in the sky. 45 seconds should be achievable now when pointing in favourable directions. So is the mount balanced well? It might be the tracking stability of the mount limiting your exposure length more than field rotation.

[Stub Mandrel]

43 minutes ago, nm1213 said:

Not able to see Polaris (1 degree north of the equator) so either have to drift align or use Celestron’s All Star Polar Align.

Surely you are in luck?

You can track objects form due east, through the zenith and down to west with minimal rotation.

You could also try mounting the mount on a wedge - in your case a near-vertical surface or even a 90-degree bracket -  so it is effectively polar aligned and rotation will be minimal.

[nm1213]

16 minutes ago, Stub Mandrel said:

Surely you are in luck?

You can track objects form due east, through the zenith and down to west with minimal rotation.

You could also try mounting the mount on a wedge - in your case a near-vertical surface or even a 90-degree bracket -  so it is effectively polar aligned and rotation will be minimal.

Hi Neil, unfortunately I was getting rotation after about 25 second exposures with the SE mount.  Sharpcap of course rotates each exposure to compensate.  However, I'd get about 30-45 minutes of stacking before I needed to crop the edges far too much to get a usable image.

You're right though about EQ and polar alignment... however pointing north and levelling wasn't precise enough to image for longer than 20-30 seconds.

Edited August 13, 2018 by nm1213

[happy-kat]

But were you trying to use the 6SE when imaging or just a camera and lens on the mount?

Edited August 13, 2018 by happy-kat

[nm1213]

Just now, happy-kat said:

But were you trying to use the 6SE when imaging or just a camera and lens on the mount?

Happy-Kat,

All my imaging so far has been with the following configurations:

1. 6SE OTA + mount, Hyperstar, ASI 385 cooled.  I could get serviceable 20 second exposures stacked for 30-45 minutes before having to heavily crop the edges.

2. 6SE OTA, AVX mount, Hyperstar, ASI 385 cooled, ASPA polar alignment routine.  I could get about 35-45 seconds unguided.

3.  (Waiting for brackets and adaptors) Skywatcher AZ-GTI, Nikon 180 2.8, same camera.  I haven't had a chance to test this yet but hope to do so within the next week.

 

N.

[rotatux]

2 hours ago, nm1213 said:

I was getting rotation after about 25 second exposures with the SE mount.  Sharpcap of course rotates each exposure to compensate.  However, I'd get about 30-45 minutes of stacking before I needed to crop the edges far too much to get a usable image.

Hello, 25s seems quite short, unless your were aiming at an unfavorable zone (near zenith).

However if you can cope with 30-45 minutes runs of stacking (is it what's called "video stacking"?), then I suggest you have a 30s break to manually rotate your camera in the focuser, and start another run. After a manual rotation you should be good again for 30-45min with approximately the same FoV and hence avoid cropping too much border due to rotation

PS: see "Field Rotation V3.pdf" (original here), don't read the text just look at the schemas for your latitude ; copy added to the post since original looks dead atm.

Edited August 13, 2018 by rotatux
PS

[happy-kat]

Several members on this thread have used and use your mount for imaging and have managed longer exposure times the variable has been your 6SE ota. It is probably heavier and with a long focal length is more challenging for the mount to track as best as it can with it.

I would re asses your imaging once you have the AZ-GTi and the camera and lens mounted on it with favourable balance, you may find with your latitude you achieve your target of 45 seconds and the cropping level is acceptable.

[happy-kat]

Would it be fabulous to get that grid pattern overlayed into one of the sky planetariums like Stellarium.

[smisy]

I tried again the comet 21P Giacobini-Zinner, Celestron Nexstar 8 SE, Alt-az mount, Huawei P10 smartphone, monochrome camera, 25mm plössl eyepiece. 2018. 08.15. 23:52, Hirschegg im Kleinwalsertal, Austria. 30 sec exposition at ISO 1600.

Edited August 18, 2018 by smisy