With high res cameras like DSLRs and the like, downloading the image can take a long time. A lot of time could be saved if operations continued during download. The rig could reposition, dither and start a new capture while download is happening. With wifi connected mounts, this could save a considerable amount of time if it takes 20s to 60s to download via wifi.

The painfully slow download is one of the last hurdles I have to solve, or at least dramatically improve, before I can fully switch over from APT to SM/Kstars/Ekos. I use a Canon T3i/600D and with preview on, it takes about a minute to download over WiFi, meanwhile the next image in the sequence waits. This delay renders shooting a sequence virtually untenable. If I turn the preview off, the sequence shoots rapidly, one shot right after another BUT, then I'm shooting blind - something I don't want to do and is a deal breaker for me. Anyone have any tips?

My advice would be: don’t rely on the WIFI network cards of the RPi. They are slow. If you cannot use a wired network then you may want to look into the WIFI network, make sure that the RPi has a good reception and a good throughput. It may seem that is already has and does but apparently that is not exactly the case.

I stopped using the WIFI network cards on my mini-pcs (different computers but similar trouble) because I couldn’t get them to respond well and connected the mini-pcs to a mesh device that transmits the data via WIFI. Before I got about 1 megabyte a sec, now about 11 and sometimes more. VNC responds MUCH better, the FITS and DSLR viewers display the images almost instantaneously and everything works smoothly.


HTH, Wouter

I did not think instantaneous previewing would be possible under ANY networked setup. It's good to know it can be done, I need to figure out how. So your mini PCs are connected directly to the mesh device with CAT5 Ethernet cables, and the laptop uses WiFi to connect to the router? Is that correct?

That’s correct. By the way, the image doesn’t show instantaneously but it takes 5 to 10 seconds to load. But that’s a lot better than a minute. Generally I image without using the preview though.


Wouter

On my portable setup wich has an RPi I stopped using Wifi, it's too slow specially for my 550D.
I am now using a 5m CAT5 Network cable between the laptop and the RPi. You don't even have to make a crossover cable.
My 550D takes 10-12 seconds to download the image and preview.