How Can I Improve? ?

[wimvb]

2 minutes ago, JohnSadlerAstro said:

Hi,

The part which takes longest with the setup is the centering. It takes soo long . The main issue is that I have a non-GoTo mount, so I cant change the slew speed off my laptop. (which is connected to the setup from inside). I essentially go back and forth giving the handset a jab, then back in again to see which way the object went, take another image, then back out again and so on. It can take up to 45 mins to get the finding and framing right. OK, I can probably do some more work getting the finders aligned precisely for better results but it is quite annoying. I don't know if it would be practical to do the centering from indoors, but using the manual guide tool of PHD?

John

Had to do something similar when I used a dslr. But since I got the cooled cmos, I can do most of the framing from indoors. Anyway, framing is easier if you align the camera sensor with the RA axis; take a 30 s exposure, and after 5 seconds, slew the mount in RA at siderreal speed. This will create a star trail. Rotate the camera until the trail is parallell with the long side of the sensor. This makes alignment easier if you want to revisit a target.

Isn't your mount driven? Can you connect an eqdir cable to it? If you can, you should look into INDI and Ekos on a raspberry pi. It's a budget alternative to a windows computer running ASCOM, but works great. You can of course also make a direct connection to your laptop. I don't know about ASCOM, but INDI has a driver for dslr, so you can do plate solving with it.

[JohnSadlerAstro]

Hi,

Thank you so much for all the advice, suggestions and support folks, I wasn't expecting such an amazing response.  

I will certainly look at the dithering amount in APT, as you say there is definitely a "walking" pattern to some of the noise.

John

[JohnSadlerAstro]

2 minutes ago, wimvb said:

Isn't your mount driven? Can you connect an eqdir cable to it? If you can, you should look into INDI and Ekos on a raspberry pi. It's a budget alternative to a windows computer running ASCOM, but works great. You can of course also make a direct connection to your laptop. I don't know about ASCOM, but INDI has a driver for dslr, so you can do plate solving with it.

It is driven, but it's the EQ5 deluxe with dual-axis drives, not the SynScan upgrade. It's guided with an ST4 off the ASI guidecam.

[wimvb]

5 minutes ago, JohnSadlerAstro said:

It is driven, but it's the EQ5 deluxe with dual-axis drives, not the SynScan upgrade. It's guided with an ST4 off the ASI guidecam.

Aligning the sensor with RA should make it easier to frame targets.

[Shibby]

Lots of good advice here already.

You can get good results with a DSLR but it does require a LOT of data and dithering, as you're well aware of. Ultimately, the DSLR has limiting noise levels, though, and OSC can't reproduce the smooth detail you can get from cooled, mono sensors. You seem to have got your optics and guiding working well, so if you were to upgrade your hardware then the camera is probably the logical next step.

I wouldn't suggest investing just yet, though, as there is more to get out of your current setup and I've always been a proponent of maximising your results with existing kit before upgrading.

2.5 hours is an awfully long time to be wasting with the UK skies... It used to take me about an hour until I built my own "observatory" and now the longest part of my whole setup is waiting for the old laptop to boot up!

[JohnSadlerAstro]

Hi,

I am planning to make a camera upgrade my next step in the hobby, but that wont happen for at least 2 years, probably far longer. I would definitely agree that its best to reach the maximum with a setup before upgrading. 

I'm hoping to get some more data on M51 or one of the globular clusters tonight, I will try doubling the dithering aggressiveness, to be honest it really wouldn't matter even if I set it to 50 pixels, as the sensor with a DSLR is so large.  

John

[tomato]

Not sure if this helps, but I set up and take down each session and the biggest single time saver was to scratch circles on the patio slabs around the tripod feet once I had the set up accurately polar aligned. A couple of times since I have not had to make any adjustments after setting up. Mind you I have a very substantial steel pier/tripod arrangement (a bit like a Mesu stand) which doesn’t flex at all. It just puts my back out on odd occasions.

+1 for Startools, I went for because I like the simple user interface and workflow, and it’s a fraction of the price of PI, but I also have PS CS2.

Your data is clearly good, more subs would help, with no observatory I somehow feel duty bound to produce an image from every session so I rarely get more than 2-3 hrs of data.