ZWO asi183MC CPU Power Spikes

[admin]

Hi,

could you please try the latest beta version of SharpCap 4.1 to see if that is any better? See https://www.sharpcap.co.uk/sharpcap/sha ... p-4-1-beta

There have been some changes made to the beta recently to improve performance and responsiveness.

Other things to check are

* You are capturing to SER file in SharpCap? It's possible to set it up to capture individual frames to PNG files, which is slow (and probably not what you want!)

* Turbo USB should be set to auto or manually to maximum

* Make sure processing options (flat frame, dark frame, etc) are *off* in SharpCap as they can use extra CPU

It's also worth checking the CPU usage/frame rate when not capturing. If the frame rate is fine when just viewing the image but drops when capturing then it narrows down the likely causes to things related to saving the images.

cheers,

Robin

[jabbourk]

Thanks Robin - 4.1-beta resulted in zero dropped packets and 19 fps. Thanks again.

Dr. Kamal Jabbour
YouTube.com/RoosterInnObservatory

[jabbourk]

OK - I got to the bottom of this problem. The issue is with solid-state drive optimization. Pre-optimization: speed test reported 154 Mbps. Post-optimization: 1,553 Mbps! A factor of ten improvement just by running disk drive optimization. Now I am able to capture a 3-minute video RAW8 (AVI or SER) at full 21 Mpixel resolution without dropping a single frame. The 3-minute video filled 68 GigaBytes.

Thanks Robin!

Dr. Kamal Jabbour
YouTube.com/RoosterInnObservatory

[admin]

Hi,

this is a very good point... Modern SSDs now often store multiple bits per cell, and writing to that sort of storage is a lot slower than the advertised speed of the SSD. To make good on advertised speeds, they put aside a fraction of the space as a high speed (single bit per cell) area. This can accept writes at the maximum speed, but may only be 10% or less of the capacity of the drive.

If using an SSD for high speed captures, it is good practice to

* Move captured files to another drive as soon as possible to keep plenty of space available on the main drive
* Use the Microsoft disk tools 'Optimise' function before capturing to ensure that all free space is fully wiped and that the high speed cache area is ready for use.

Hope that you get lots of good images now that everything is working!

Robin