Frame download time

Hello everyone,

I am sorry to bring this topic up again, but today I installed NINA to give it a try due to long download times with SGP (I already knew that sharpcap was much faster already…)

I use a Intel compute stick with a USB 3 Hub connected to the ASI1600MM, ZWO Filter wheel + 224MC guide camera.

I really love SGP, but with short exposure times, it takes forever to shoot hundreds of frames due to the time it takes to download them from the camera.

I have used the same setup for both programs, SAME driver and the tests were performed one right after the other. I shot 10 x 2 second frames, first with NINA and then with SGP. Please see videos below:

  • NINA took 33 seconds to expose and download 10 x 2 second frames, which means an average of 1.3 seconds to download an image.

  • SGP took 92 seconds to expose and download 10 x 2 second frames, which leaves us with an average of 7,2 seconds per download.

NINA video:

SGP Video:

I am up for any testing… I’d like to keep using SGP, but with my need for short subs, this is a big issue. There should be some kind of fix.

Are you using the same drivers between the two applications? Both ASCOM? Both Native? For the most part SGPro is not involved with download speed… we just ask the driver to do it.

The other area that can possible make a difference (and I can’t speak for NINA)… some cameras offer a “High Download Speed” option. SGPro forces this off for sequence images as it comes at the cost of image quality. Not sure if your camera supports it or if NINA has it turned on.

Hi Ken,

Yes, I am used the same driver for both apps for the test. That was the first thing I checked beforehand to make sure.

I will check about the “High Download Speed” right now to see if there is any option regarding that in NINA.

Also mention that Image History is Off in SGP

Yes, but what driver is it? ASCOM or native?

Also, if using ASCOM, check the camera’s ASCOM options to see if it’s on there…

I use ZWO driver, version 1.14.0715 according to what the system says.

The only option I see in NINA as we speak is USB Limit = 100

Ok… sounds like you are using the Native driver. Please give this a shot with the ZWO ASI ASCOM driver. SGPro DOES control the download speed for the native driver and it may be sluggish? I don’t know for sure, but we are probably moving away from native ASI support as the ASI ASCOM driver matures.

Ok… NINA said driver 1.14.0715… Windows says v1.0.1.0

We are talking about the ones from, right?

I will update right now to make sure and I will report back…

Yes, but that page includes both the native and ASCOM drivers. Make sure that you get and install the drivers from the “Native Drivers” section. After that, install the driver from the “ASCOM Drivers (optional)” section. In SGPro, make sure that you choose the ASI option. DON’T CHOOSE “ZWO Camera”… that is the native option.

Perfect, thanks.
On the wa…

Of course, when comparing speeds between applications now, please make sure you use ASCOM drivers in both… I am uncertain of how to choose an ASCOM camera in NINA, but I suspect it’s pretty straight-forward.

Now, the camera is in a position where download speeds are 100% dependent on how the ASCOM driver chooses to do it, effectively removing SGPro from the picture. Keep in mind that the “High Speed Download” stuff discussed above it applicable to the ASCOM driver. Ensure that you check the driver’s options (in NINA) to see if it has this mode and that it is tuned off.

Ok, so…

When using the ASCOM driver in SGP instead of ZWO, the integration + download time for 10 x 2sec frames has gotten worse. 120 seconds instead of 92… which means 10 sec download time per single frame for my setup.

When using NINA I directly get an exception… Camera download failed :sweat_smile:

I will keep working on it

Fwiw, I think that ZWO exposes it’s high-speed mode through a field in the ASCOM options called “Image Type”. I am not sure… this should be set to RAW16.

Yeah, Image Type was already at RAW16.

I seem to have some kind of trouble with the ASCOM one… either NINA or SharpCap (not with SGP) throw the exception System.OutOfMemoryException when using this driver. Both, however, work using the ZWO one

Interesting discussion! Please keep us posted about any progress/update.

Thanks and clear skies,

For the moment I haven’t managed to make NINA or SharpCap work with the ASCOM Driver.

SGP did, but took longer to download than with the native driver.

I will set everything up in a different computer and see what I come up with.

Interesting–I have been using ASI cameras (1600 and 183) and was recently taking a lot of flats, darks and bias (rebuilding libraries for darks and bias). The download speed per frame was 2-3" at most. Nothing like 7". That’s with the ASCOM driver.

I too have the ASI1600MM-Pro with the RAM buffer built in. I recently tried N.I.N.A. because I’d seen on forums that the download speeds were a lot quicker compared to SGP and they are. SGP is great, the best acquisition software I have used and I have recommended it to others that have gone on to purchase it. But if it could match the download times for N.I.N.A. that would be nice, a quick look indicates that I am using the native ZWO driver in SGP (ZWO Camera rather than ASI camera). I will try to run a comparison soon to see whether there is a difference in download speeds.


We would need more information on specific camera models and drivers used. It is worth repeating that, for the most part, SGPro is not involved in download speeds for most of the cameras it controls… the exception to this is SBIG, FLI, Canon and Nikon. Everything else runs the download in the ASCOM driver. So… NINA does seemingly have more native driver implementations in the code base and, in these implementations, they could have code that is more efficient than what is in the ASCOM driver. SGPro simply cannot survive if all of the camera implementations are against native drivers.

Lastly, it has been said before, but bears repeating: Many cameras have a notion of “hi-speed download”. SGPro does not allow high speed download for sequence images, because it comes at the cost of quality.


  • When comparing download speeds, make sure you compare ASCOM against ASCOM
  • If the speed at which the ASCOM driver downloads your image is slower than the hardware will allow for, check ASCOM settings and contact the driver author
  • Ensure that, between applications, you are comparing normal speed download against normal speed download

I’m fairly certain NINA has the inter-frame logic threaded, including the downloading of the completed exposure. It starts the next frame before the downloading is fully complete. This is not related to driver or driver config discrepancies.