Frame rates

gordonewen

Sam, I have written before wondering why I can't get anywhere near the quoted frame rate of 30fps with my ASI 120MM camera. I have been using a Toshiba i3 laptop with Intel processor and AMD graphics card. The best frame rate I get is about 15 at whatever setting I have for the USB traffic. I have also optimised the buffer in Firecapture.

I have just got a Dell i7 laptop, 16Gb ram, not an AMD chip in sight, and I only get a frame rate of 18fps. Have I got a duff camera? I am getting very frustrated with this camera.

Regards

Gordon

james_screech

What exposure time are you using? If for example you have the exposure time 100ms you could only get 10FPS.

Is the FPS the same during both preview and capture? If it's only slow during capture it could be that your disk cannot save the data fast enough, I had this problem and now use a RAM disk, with 16GB you could easily do the same.

James

gordonewen

Hello James, thanks for your reply. I am imaging the sun and my exposures time are typicaly 2ms so there should be no issue there. When the camera is running but not recoring video the frame rate fluctuates between 28 and 6 fps, when shooting it is between 23-8 with the average over a run being 18 fps.

Are you using Firecapture for saving first to RAM? I did have a quick look at this feature yesterday and it didn't seem to make any difference, I will have another go later. Or do you mean something different.

Regards

Gordon

Sam@ZWO

it should be your harddisk's speed problem if you can preview at 28fps

you can try to save the data to a empty driver. then it can save at the fastest speed.

and there is one thing need to take care when do ha solar imaging,

over exposure will make the camera slower too

james_screech

gordonewen wrote:

Are you using Firecapture for saving first to RAM? I did have a quick look at this feature yesterday and it didn't seem to make any difference, I will have another go later. Or do you mean something different.

No it's not a feature of FireCapture, but another application that turns part of your computers RAM into a virtual disk drive. My laptop has 6GB and I use 3GB of this as a RAM disk, I use Firecapture to save it's captures to the RAM disk and after the capture copy the files to my hard disk as depending on the setting the RAM disk may loss you data when the computer is switched off.

This is the one I use http://www.radeonmemory.com/software_4.0.php but there are others around if you look.

James

gordonewen

Sam, James, thanks for the replies.

Sam, I will try an external drive for download.

james, I will have a look at the link you sent, sounds good. I used to use Lucam Recorder with my DMK cameras and that had the facility to initially load to RAM, it was very good.

REgards

Gordon

gordonewen

James I tried the Radeon Ramdisk. It didn't make a difference unfortunately. At full frame I got 23 fps and just saving to disc was 22 fps. I also tried saving to an external hard drive with same result. Looks like I am stuck at 22/23 fps.

Wonder if ZWO will bring out a USB3 version of the camera?

Regards

GOrdon

Sam@ZWO

yes, ASI120MM-S in on its way

we will invite you to test if you don't mind

I am sure its faster than the USB2.0 one

gordonewen

Sam, that would be great. Look forward to it very much.

Regards

Gordon

gordonewen

Sam, when would you anticipate the new camera being available to test?

Regards

Gordon

Sam@ZWO

we will start batch testing from next month