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MINIX NEO Z83-4 mini PC is In The House

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#26 ccs_hello

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Posted 11 January 2017 - 11:05 PM

Please note J1900 is one of the most powerful ATOM class CPU in its generation (Silvermont architecture.)

Higher TDP basically means it can tolerate more power being consumed <-- of course, the extra heat generated needs to be taken off and dissipated.

Higher power being consumed means less thermal throttling and the full clock rate can be sustained (if sufficient heatsink is used.)

It's a more capable CPU than the super power-saving type.

 

J1900 is the nettop class.

Server > Nettop > Netbook > Tablet > Mobile

 

Clear Skies!

 

ccs_hello



#27 james7ca

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Posted 12 January 2017 - 07:44 AM

I've been doing more tests on the TransFlash/microSD card on the Minix and at least with SharpCap and Firecapture the results seems highly unpredictable. On some trials and system restarts I can get around 4.5 fps at full resolution with the ASI178MM and then I'll restart the system and I get only about one half that rate. It's very odd and I've even seen cases where the disk benchmarking programs that I'm using show the same variation. I've had some trials where the ATTO benchmark will show sustained writes at nearly 70MB/s with reads at 80MB/s and that's probably about the best I could expect given that the X5-Z8300 SoC apparently has a 800Mb/s maximum on its SD card interface (note the difference between megabytes -- MB -- and megabits -- Mb -- and thus assuming some overhead and using 10 bits per byte of transfer). Then I'll reboot and run exactly the same test again and ATTO produces a maximum of 40MB/s on the writes.

 

This is really only an issue when doing full-resolution/full-frame captures at the highest speeds possible (meaning exposure times less than about 200ms, something you aren't likely to do on DSOs).

 

I also did some more tests using my Samsung T3 SSD using the same USB3 port for both the camera and the disk (over a powered USB3 hub). What I found is that you can get write speeds of well over 100MB/s but it really doesn't help with the capture frame rate in SharpCap because many of the frames from the camera get dropped, so you generally end up with the same effective frame rate as you get with the microSD card (between 4.5 and 5 fps). However, with Firecapture I was able to get a bit more, maybe 8fps with the SSD (the latter would be a data rate of just over 100MB/s).

 

In that regard, I should probably comment on the following post from Xeroid:

 


Maybe I'm doing something wrong but I see 30 frames/second on SharpCap from the ZWO 178 at full reso connected to the Minix Z83-4 USB3...

 

The problem here is that you'd need 30 frames/second x 12.5 MB/frame or about 375 MB/s of disk i/o to support that kind of capture rate. While that might be possible with a VERY fast SSD running on a dedicated USB3 port I don't think you should expect performance like that with the "ZWO 178" on the Minix.

 

In any case, I'm still working on installing and testing everything on the Minix. So far it looks good and I may just have to accept that when using the microSD card that I may be somewhat limited in maximum frame rate (when working at full resolution on the ASI178MM).


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#28 james7ca

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Posted 12 January 2017 - 11:54 AM

Just to give some perspective as to i/o rates and potential bottlenecks on a system like the Minix with its Atom X5-Z8300 processor, I ran SharpCap on an Acer Core i3 notebook using my Samsung T3 SSD and the ASI178MM camera and I got full-resolution capture at 24fps with a write speed of at least 250MB/s. Furthermore, the Core i3 processor was running at below 30% utilization. But, the Core i3 had 20GB DRAM versus the 4GB in the Minix. Compare this with the 5fps I got on the Minix with 100% CPU utilization and a data rate around 100MB/s (when using the SSD).

 

I guess this shows that you don't want to do demanding planetary capture on a system like the Minix. As I noted before, you'd probably be okay with a small ROI, but don't expect high frame rates to come easy when working full-frame with a camera like the IMX178 (full frame just over 6 mega pixels).

 

Of course, I'm testing only a single sample, so maybe there is something wrong with my unit or the software installation. But, I don't think so since in most areas this is following the same pattern I saw on the Intel Compute Stick and my other systems (another Core i3 -- now not working -- and a Celeron-based netbook).


Edited by james7ca, 12 January 2017 - 11:57 AM.


#29 Poochpa

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Posted 12 January 2017 - 12:37 PM

James, instead of an SD card, how about trying a usb3 thumb drive in the Minix's usb3 port to see if that helps.

Mike



#30 entilza

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Posted 12 January 2017 - 06:41 PM

It still will go through the USB interface internally.

James did you try the ramdisk?

#31 james7ca

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Posted 12 January 2017 - 07:34 PM

Martin, thanks for the suggestion about the RAM disk. However, that really wouldn't work given my typical process for taking images of the moon, since I often capture sequences that are 4GB to 16GB is total size. Also, the CPU is already running at 100% so there would be no good way to off load those images from the RAM disk in any realtime manner.

 

The fact that the CPU is maxed out when capturing with SharpCap and Firecapture is probably indicating that it may be a CPU issue rather than just a relative slowness in either the USB3 or TransFlash ports.

 

I'm going to do some more tests comparing the Intel Compute Stick and the Minix to see if they behave in a similar manner. It could be that the Compute Stick is/was doing the same thing and I just never noticed, since the Minix sometimes gives performance on the microSD card that seems similar to what I had on the Compute Stick (meaning it may be more of an issue with consistency than with reaching the same limit on both devices).

 

As for trying a USB3 thumb drive, I don't see how that could be any better than my Samsung T3 SSD. Also, I don't think I have any thumb drives that are as fast as my class 10 U3 microSD card. Most thumb drives are ridiculously slow on writes. However, I may give it a try since it would be another data point, but I don't know whether I have a thumb drive that can even exceed 50MB/s on writes.



#32 ccs_hello

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Posted 12 January 2017 - 08:32 PM

Worthwhile to note in 2016 (gen 2) Intel Compute Stick, it's more like a form factor than a single class of miniature form-factor PC.

Case in point, the most common sub-$200 Intel Compute Stick has limited RAM, eMMC, and use ATOM processor (its CPU typical list price is $27),

while its big brother Compute Stick (MSRP $500) uses the main stream Intel Gen 6 Skylake CPU (e.g., Core M5 m5-6Y57, list price $281, just the CPU by itself!!!)

Naturally the latter has a bit more RAM (e.g., 4GB.)

 

Bottom-line is to show you that

there is a lower-tier system (and very low-end CPU, called ATOM, from Intel perspective, to compete with ARM CPU as used in very low end compute devices)

and there is a high-end/less-compromises type (but tiny form factor) of compute stick.

They are apples and oranges.

 

Clear Skies!

 

ccs_hello


Edited by ccs_hello, 12 January 2017 - 08:34 PM.


#33 entilza

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Posted 12 January 2017 - 09:02 PM

Martin, thanks for the suggestion about the RAM disk. However, that really wouldn't work given my typical process for taking images of the moon, since I often capture sequences that are 4GB to 16GB is total size. Also, the CPU is already running at 100% so there would be no good way to off load those images from the RAM disk in any realtime manner.

 

The fact that the CPU is maxed out when capturing with SharpCap and Firecapture is probably indicating that it may be a CPU issue rather than just a relative slowness in either the USB3 or TransFlash ports.

 

I'm going to do some more tests comparing the Intel Compute Stick and the Minix to see if they behave in a similar manner. It could be that the Compute Stick is/was doing the same thing and I just never noticed, since the Minix sometimes gives performance on the microSD card that seems similar to what I had on the Compute Stick (meaning it may be more of an issue with consistency than with reaching the same limit on both devices).

 

As for trying a USB3 thumb drive, I don't see how that could be any better than my Samsung T3 SSD. Also, I don't think I have any thumb drives that are as fast as my class 10 U3 microSD card. Most thumb drives are ridiculously slow on writes. However, I may give it a try since it would be another data point, but I don't know whether I have a thumb drive that can even exceed 50MB/s on writes.

 

For sure I just suggested a few frames to see the throughput, should eliminate any internal interfacing if it's somehow bottling up the CPU.  I am not sure if you eliminated all the extra bloatware as well.  I even have antivirus disabled permanently.  I really slimmed down my compute stick.



#34 james7ca

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Posted 15 January 2017 - 06:32 AM

We've had a lot of rain in California lately, but tonight we had mostly clear skies (with a very wet ground and high humidity) and I had my first opportunity to use the Minix mini PC to take actual DSO and lunar images. All of my previous work had been running tests and simulations indoors.

 

Everything worked well and I had a chance to check out my new wireless access method. Instead of using remote access software (TeamView, Microsoft Remote Desktop, or VNC, etc.) I just use the wireless display feature in Windows 10 Anniversary. It has good video performance and low overhead and the real kicker is that you don't need a network of any kind. It works point-to-point over WiFi and you can set it up so that there is no login or authentication other than the very first time you connect (kind of a pairing operation that is remembered by the clients). I've also figured out a way to connect automatically during boot so you just start up both computers and you are all set. When the wireless display is in full-screen mode it is exactly as if you had a wired display and keyboard/mouse attached to the Minix. But, you can minimize the window and then you're right back to the normal desktop on the other computer. The option of not using a network should be a real advantage for field operation, since you won't need a WiFi basestation or any kind of ad-hoc network. 

 

One disadvantage, since you aren't using a network there is no file sharing, but I suppose if you want that you could just connect both systems to your local WiFi network and do normal file sharing. However, since I'm storing all of my images on a microSD card I can just pop the card out and transfer files that way (and a lot faster than over any WiFi network).

 

I wrote some simple scripts to help with the boot-time connection and I also figured out a way to use the power button on the Minix to reconnect the wireless display in case something goes wrong (I've never had a disconnect during normal operation, but I wanted a simple method to reconnect at will).

 

If anyone wants to try this technique then I'll create a new thread with details on the setup.


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#35 ccs_hello

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Posted 15 January 2017 - 10:57 AM

James,

 

I think WiDi is so foreign to most of us and would definitely help a few folks, not just limited to Minix-Neo PC

if it is in a new thread.

 

Thanks for the great work!

 

Clear Skies!

 

ccs_hello



#36 entilza

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Posted 15 January 2017 - 11:46 AM

Cool James. A thread on miracast would be interesting. I will have to update my compute stick to try it fully. Just not sure how this would work casting to an android or apple tablet.

#37 D_talley

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Posted 15 January 2017 - 02:45 PM

If you are talking about WiDi, it is no longer supported by Microsoft and you cant download it from them. 

I just tried Miracast and it does not connect from PC to PC from the little I played with it.  I may be missing something.



#38 james7ca

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Posted 15 January 2017 - 07:50 PM

If you are talking about WiDi, it is no longer supported by Microsoft and you cant download it from them. 

I just tried Miracast and it does not connect from PC to PC from the little I played with it.  I may be missing something.

Yes, WiDi is no longer supported by Intel, it was cancelled/discontinued and replaced by the Miracast standard.

 

In any case, you need the Anniversary Edition of Windows 10 in order to have a PC act as the target for the wireless display. I suspect that this new feature is based both upon Miracast and WiFi Direct.

 

Also, I'm fairly certain that only a Windows device can act as the receiver, so no support for Mac OS, Linux, Android, or iOS.

 

However, you should be able to use regular Miracast to receive the video "broadcast" from the scope-side PC (in my case the Minix). That means if you had a wireless keyboard and mouse you wouldn't even need a PC on the receiving end, just any Miracast device, TV or display with a Miracast wireless display adapter. That would make a pretty cheap system, one PC (like the Minix) to control the mount, scope, and camera, a wireless keyboard and mouse, and a "dumb" display device with a wireless display adapter.

 

However, I like having the second PC (notebook) to act as both the video receiver and the keyboard/mouse for the remote system.


Edited by james7ca, 15 January 2017 - 08:05 PM.

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#39 D_talley

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Posted 15 January 2017 - 08:16 PM

Thanks for the clarification.  Too bad is it only a Windows option.  I use a Mac inside the warm house to connect to my headless systems at the mount with Microsoft Remote desktop.  I bet that there will be a port to the Mac system in the future.



#40 james7ca

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Posted 15 January 2017 - 09:04 PM

As somewhat of a teaser, below is a screen shot of the minimized wireless display option running on my Acer notebook computer (it's showing the Windows desktop of my Minix computer which is outside by my imaging scope). The center window is the minimized desktop on my Minix (you can, of course, go full screen) showing PhD in the foreground guiding and Sequence Generator Pro in the background capturing images. The larger desktop is my Acer notebook, running at a resolution of 1920 x 1080 and I've blurred a rectangle on the left for privacy concerns and to help eliminate any confusion about which desktop is which.

 

Here is an article on the new wireless display support under the latest version of Window 10 (this is the article that gave me the idea of using this technology to do remote-style access to my Minix mini PC).

 

  http://www.laptopmag...wirelss-display

 

The only thing missing from this article is how you can get the two devices to connect automatically without any manual input on the remote device. I wrote a simple startup script that runs on the Minix to do this, it's part of the "secret sauce" that probably still needs some more tweaks.

 

The article suggests that you may have intermittent difficulty trying to connect, but I haven't had any problems thus far (it has worked almost flawlessly, but I have seen a few cases of distorted video, either very minor or something that just lasts for a second or two -- the latter very rarely). This could be caused by interference from my USB3 camera, since I'm not really sure what frequency band is being used by the wireless display, it could be 2.4GHz. Also, as you move away from the broadcasting device (a long way, 50 feet or more and when going through walls) you can get distorted video, but the connection seems to hold pretty well even if the video starts to look pretty dodgy.

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#41 liquid4

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Posted 22 January 2017 - 06:26 PM

What about using the Minix NGC-1, with its larger 128GB storage, 3 USB3, and N3150 processor? But kind of expensive.



#42 james7ca

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Posted 22 January 2017 - 06:50 PM

What about using the Minix NGC-1, with its larger 128GB storage, 3 USB3, and N3150 processor? But kind of expensive.

IMO, not nearly as good of an option, more expensive, requires more power to run, you lose one USB port, and no microSD card slot.


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#43 FiremanDan

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Posted 24 January 2017 - 11:51 AM

 I am thinking I might order one of these soon. I might consider doing a little Solar/Planetary but 99% of my work is DSOs. If you had to choose based on your experience, would you suggest this or the base model 2nd gen Computestick? 



#44 james7ca

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Posted 24 January 2017 - 04:50 PM

 I am thinking I might order one of these soon. I might consider doing a little Solar/Planetary but 99% of my work is DSOs. If you had to choose based on your experience, would you suggest this or the base model 2nd gen Computestick? 

IMO, the Minix is the better device. However, if you plan on mounting the computer on the optical tube then you may want to consider the differences in the sizes of the devices (but add a USB hub for the Compute Stick).

 

Another difference is the power requirement. The Compute Stick requires 5VDC and it's not too hard to find small and relatively cheap lithium ion battery sources that supply 5 volts at 2.4A or slightly better (but note, some power sources/batteries/recharging devices won't supply enough total current to power the Compute Stick, since in theory it can require up to 3A). The Minix runs on 12VDC which is kind of convenient because a lot of other astronomy-focused devices also run on 12V.

 

However, since I'm planning on using a deep cycle marine battery to power the Minix it occurred to me that those types of batteries really don't output 12 volts and when fully charged they can output up to 13.4VDC. That's about a 10% over voltage and to be completely safe I decided to use a $20 power regulator that outputs 12 +/- 0.25VDC at 5A with inputs that can range from 10VDC to 36VDC. That should be enough to power the Minix and a small, self-powered USB hub (if needed, although right now the 4 ports on the Minix support all of the devices that I need). While I was at it I also purchased a small and relatively inexpensive digital voltage and power meter that I can place inline to monitor the battery power since I don't want risk completely draining the battery (the meter will go between the battery and the regulator, thus it will measure the voltage from the battery and also the total watt hours since reset).

 

Anyway, if you are planning on going mobile that is another thing to consider. 

 

The power regulator and digital meter:

 

  http://a.co/9WyEzFX

 

  http://a.co/5FPfsSa

 

Lastly, a quick update on the performance of the microSD/TransFlash card slot. For whatever reason, during all of my recent testing I seem to be getting a pretty reliable 50 to 60MB/s on writes to my 64GB Samsung Pro U3 cards which I think is about as good as I should expect from one of these Atom-powered devices. So, while the Intel Compute Stick MAY be a little bit faster on the writes the differences are very minor (maybe 15%, but to confirm I'd have to go back and test the Compute Stick again, perhaps it doesn't reach 70MB/s that often). Note, you need a FAST microSD card to reach these rates, most cards will be much slower but still fine for most DSO work).

 

Also, my wireless display (Miracast) link between the Minix and my notebook computer continues to work very well and very reliably for the remote access over WiFi.


Edited by james7ca, 24 January 2017 - 05:37 PM.

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#45 FiremanDan

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Posted 24 January 2017 - 05:08 PM

Awesome, thanks James! 



#46 Ricky

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Posted 24 January 2017 - 07:38 PM

 

 I am thinking I might order one of these soon. I might consider doing a little Solar/Planetary but 99% of my work is DSOs. If you had to choose based on your experience, would you suggest this or the base model 2nd gen Computestick? 

IMO, the Minix is the better device. However, if you plan on mounting the computer on the optical tube then you may want to consider the differences in the sizes of the devices (but add a USB hub for the Compute Stick).

 

Another difference is the power requirement. The Compute Stick requires 5VDC and it's not too hard to find small and relatively cheap lithium ion battery sources that supply 5 volts at 2.4A or slightly better (but note, some power sources/batteries/recharging devices won't supply enough total current to power the Compute Stick, since in theory it can require up to 3A). The Minix runs on 12VDC which is kind of convenient because a lot of other astronomy-focused devices also run on 12V.

 

However, since I'm planning on using a deep cycle marine battery to power the Minix it occurred to me that those types of batteries really don't output 12 volts and when fully charged they can output up to 13.4VDC. That's about a 10% over voltage and to be completely safe I decided to use a $20 power regulator that outputs 12 +/- 0.25VDC at 5A with inputs that can range from 10VDC to 36VDC. That should be enough to power the Minix and a small, self-powered USB hub (if needed, although right now the 4 ports on the Minix support all of the devices that I need). While I was at it I also purchased a small and relatively inexpensive digital voltage and power meter that I can place inline to monitor the battery power since I don't want risk completely draining the battery (the meter will go between the battery and the regulator, thus it will measure the voltage from the battery and also the total watt hours since reset).

 

Anyway, if you are planning on going mobile that is another thing to consider. 

 

The power regulator and digital meter:

 

  http://a.co/9WyEzFX

 

  http://a.co/5FPfsSa

 

Lastly, a quick update on the performance of the microSD/TransFlash card slot. For whatever reason, during all of my recent testing I seem to be getting a pretty reliable 50 to 60MB/s on writes to my 64GB Samsung Pro U3 cards which I think is about as good as I should expect from one of these Atom-powered devices. So, while the Intel Compute Stick MAY be a little bit faster on the writes the differences are very minor (maybe 15%, but to confirm I'd have to go back and test the Compute Stick again, perhaps it doesn't reach 70MB/s that often). Note, you need a FAST microSD card to reach these rates, most cards will be much slower but still fine for most DSO work).

 

Also, my wireless display (Miracast) link between the Minix and my notebook computer continues to work very well and very reliably for the remote access over WiFi.

 

I just put together a Gigabyte Brix (N2807 dual Celery) and one of the reasons why is the 12v input.  Having already used it effectively during remote sessions it did not dawn on me until reading the above post that i've been feeding it 13+ vdc the entire time.  I guess I got lucky in that the ps is tolerant of the slight over voltage.



#47 james7ca

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Posted 25 January 2017 - 02:13 AM

I think the 13+ volts from a battery are probably okay, like I said it's only about a 10% over voltage and that may be fine. However, since it's computer equipment I though it would be a good idea to use a voltage regulator so the input stays right at 12VDC no matter what the state of the battery. I may even mount the regulator up on the optical tube so as to handle any voltage drop over the wiring from the battery to the computer.

 

I just searched on the internet to see what is usually required from a computer power supply and It appears the recommendations are +/- 5 percent for a 12V supply. However, that's for the actual power internal to the computer and I don't know if the 12VDC input on the Minix gets any conditioning internally or whether that 12V input is used directly. If so, it might be a good idea to use a regulator although the 12VDC input must be reduced down to 5VDC and 3.3VDC for most of the internal components.

 

I was planning on using a separate battery for the computer, but with the regulator maybe I can just run an unregulated line to the mount for its 12 volts and then use the regulator on the line to the computer. One thing you probably don't want to do is to run something like a dew heater on the same battery that is used for the computer -- that could cause noise and rapid fluctuations in the supply voltage.


Edited by james7ca, 25 January 2017 - 02:25 AM.

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#48 james7ca

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Posted 28 January 2017 - 10:40 AM

I got my voltage regular and meter from Amazon and put them to work last night for a session that lasted just over six hours. I was using a 14Ah Deep Cycle AGM battery and had the Minix mini PC with all four USB ports active and (of course) the WiFi link to my remote PC (using the wireless display feature of Window 10 Anniversary Edition). The capture camera was a ZWO ASI178MM and the guide camera was an ASI120MM and I was also running a filter wheel (inactive, I just did luminance), a Tele Vue digital focus indicator, and the mount control (over a two port USB to serial adapter).

 

With all of that equipment I was averaging about a 0.5A draw with Sequence Generator Pro, PhD, and the focus indicator and mount control software. Here is an image of the display on the BAYITE-PZEM-031 meter showing the voltage output from the regulator (right at 12VDC), the current draw (amps), the power draw (watts), and the total watt hours since the meter was last reset.

 

It looks like this battery will get me at least 8 hours of operation (with a discharge level of about 50%).

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  • Power Meter Running Minix mini PC.jpg

Edited by james7ca, 28 January 2017 - 10:48 AM.

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#49 james7ca

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Posted 28 January 2017 - 11:30 AM

A quick note on lasts night's imaging. Everything worked well during the 6-hour session. However, now that I've moved outside to use the Minix for actual imaging I've had a few unexplained disconnects between the remote PC and the Minix. This seems to happen about once every two or three hours (I had one disconnect last night, two during a longer session on a previous night). Fortunately, the Minix continues to run so I don't lose any work, but I have to restart my remote PC (an Acer notebook running Windows 10) and then reconnect to the Minix to get the display to work again. I've never actually been watching the connection when it fails, it always seems to happen while I'm just letting the system run by itself. Then, when I return the mouse pointer is frozen on the Acer notebook and I have to force quit the Connect app.

 

In any case, after weeks of rain we've finally had some clear weather here in California but the seeing conditions are so bad that it is hardly worth imaging. The stars in the subs are nice and round but the FWHM is running over 6 arc seconds. During the summer and with this same setup I've gotten FWHM down near 2 arc seconds with RGB and around the 1.5 arc second range in Ha. I think I may have to switch to my 105mm camera lens for the remainder of the winter.   :(

 

Note, the MetroBlue astronomical seeing website is showing seeing between 1 and 2 arc seconds which is completely bogus. At least where I live that service is totally unreliable. Meanwhile the Clear Sky Chart is showing the seeing as average to poor. However, both services are showing improved seeing for Saturday night (if the clear skies actually hold).


Edited by james7ca, 28 January 2017 - 07:05 PM.

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#50 Ricky

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Posted 28 January 2017 - 12:19 PM

Is it possible that your Acer is going into sleep/powerdown mode and not properly recovering?  I rdp and haven't run into any issues so far.  Maybe its just a bug as well that will get fixed on a future Win 10 update...


Edited by Ricky, 28 January 2017 - 12:19 PM.



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