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By Cosmic Geoff
Here are some EEVA-style images made with a 102mm f5 Startravel, SLT mount and ASI224MC planetary camera. I don't claim that they are very good, but would point to the modest equipment used (the camera cost more than the OTA did) and the fact that these are single exposures of about 5 seconds.
I have previously tried imaging globular clusters with a C8 but the results were dire.
One should also compare them with the eyeball view through a telescope of twice the size.
I also tried imaging the region of Pluto, but on interpreting the result it appears that I missed the planet's position and also was not giving enough exposure to pick out objects that faint.
I wasn't sure where to post this tip....it is probably of most use here....
Many of us with observatories or indoor Mission Control use Windows 10 Pro Remote Desktop to control a scope side computer running camera and scope control software from a second computer indoors. This works superbly at 1080p resolution.
However, I have struggled for a year trying to perfect a wireless solution that works with 4K UHD cameras terminating in a 4K UHD display. Until now, whilst cat 6 cable does work fine, wireless even at 5Ghz 802.11ac has struggled with some lag and poor performance. I have spent a fortune upgrading wireless adapters and range extenders, but this isn't the issue!
Here is a solution;
1. Seperate your dual band network into distinct 5Ghz and 2.4 Ghz channels.
This is easy with (say) a BT Home Hub. If you don't do this, it can be a bit hit or miss whether your 5 Ghz wireless adapters connect to the right channel. You will now see TWO channels, one at 2.4 Ghz with a suffix like <hub name> and another at 5 Ghz named <hub name -5>. Connect your 5Ghz adapters to the latter. If your internal adapters are merely 2.4Ghz, you can disable them via Device Manager and plug in a USB version costing around £5. Note that at 5 Ghz wireless range might drop. If so, a Netgear EX8000 wireless extender is recommended as it employs 'mesh' technology.
2. ONLY if you have a fast network, and powerful CPUs and quality graphics card, try DISABLE 'RemoteFX compression' in RDP.
This allows uncompressed screen data to flow across RDP. I have found this improves performance whether using 802.11ac wireless or cat 6 cable. What RemoteFX compression appears to do is limit effective RDP speeds to under 10Mbps (due to translation times). That is crazy if you have 433 Mbps adapters, and an 802.11ac network (or catv6 cable). Unleash the beast! Send across uncompressed data! The issue is not with speed or bandwidth, it is an artificially imposed limit in RDP.
To do this type 'Edit Group Policy' in the Windows 10 Pro search box (doesn't work in Win 10 Home). You need to drill down through about five levels of Windows Configeration Folders, and Administration Templates and Remote Desktop Services/Host folders to find a utility named <Edit RemoteFX Compression>. In that, your options are <disable> compression or <enable> a compromise mode.
If you don't know how to do this try Googling 'Disabling RemoteFX Compression' to find a lengthy Microsoft tutorial. Or visit https://docs.microsoft.com/en-us/windows-server/administration/performance-tuning/role/remote-desktop/session-hosts .
I deliberately don't here state the quick route sequence to access this deeply embedded network utility command because you are delving deep into developer/administrator territory and do need to understand what you are doing and how to revert to your original RDP settings if your network can't handle these levels of uncompressed screen data. We don't want any novice attempting this on a cheap Compute Stick on an inadequate network!
3. When employing RDP from your computer indoors, select <WAN 10 Mbps> or <LAN 10 Mbps> as appropriate via <Options><Experience>. The default <auto-select my connectivity> often selects too low an option. The irony here is you can select this and still not enjoy faster speeds unless you have edited/disabled RemoteFX compression.
I now have Atik Infinity plus CPWI software running in an end to end 4K UHD system terminating in a 4K UHD monitor. Over 802.11ac wireless it is now rock steady. Over cat 6 cable my system is now turbo powered. If you don't need RemoteFX Compression, don't let it restrict your network performance. It is evidently set to ensure it works on lowest common denominator networks. If you have a fast network/CPU, disable RemoteFX compression and finally release the beast of 4k UHD over RDP.
By Cosmic Geoff
Here is an image of Jupiter, taken around 6am on 15 Feb with my C8, ASI120MC, +ADC, processed in Registax6 from around 30% of 3000 frames.
I am fairly pleased with it considering that the altitude of the planet was only about 12 deg. and the seeing looked bad when I tried to focus on a star. And it shows the Great Red Spot.
By Cosmic Geoff
I had another go at imaging the shrinking Mars, this time without and with a x2 Barlow lens. The results are better with the Barlow, which is what one is led to expect. For whatever reason (probably bad seeing and/or low planets) when I tried a Barlow previously it just made the blur bigger. Equipment: C8 SE, ASI120MC, x2 Skywatcher kit Barlow element screwed directly into 1.25" barrel of the ZWO camera. This does seem to give x2 in practice. I did not use an ADC on the grounds that I shouldn't need one with Mars at an altitude of over 40 degrees.
3000 image video captured with Sharpcap. Processed in Registax6. I found that the Sharpcap exposure histogram did not appear to work on such a small image, so had to estimate the exposure. Yes, optical ADC correction would be better, but the dispersion seemed very small. Blowing up the image x2 in Registax showed a small colour fringe, which I took out with a single point of correction.
The images show some surface detail though the contrast is low (if you are using a flatscreen try viewing from below: ?) Mare Sirenum, with Mare Acidalium just discernible foreshortened at upper right.