All Sky settings

Using SharpCap for other Astro Imaging such as all sky cameras and meteor detection
dfisherows
Posts: 12
Joined: Fri Jun 09, 2017 4:39 pm

Re: All Sky settings

Post by dfisherows » Sun Oct 01, 2017 1:46 pm

Here is a link to the video on my YouTube channel. Ignoring the title the video is 23 secs long. Each raw video was 3-4 secs in length and I can't figure out why.

https://youtu.be/hIjBtXqbKAw

User avatar
admin
Site Admin
Posts: 1889
Joined: Sat Feb 11, 2017 3:52 pm
Location: Vale of the White Horse, UK
Contact:

Re: All Sky settings

Post by admin » Sun Oct 01, 2017 2:57 pm

Ah, that makes sense - SharpCap sets a frame rate of 30fps on the created AVI file (regardless of the actual frame rate or exposure time). This is usually a good value as you really wouldn't want to be waiting 30s for each frame to change if it set the true frame rate for your exposure times and it means you have a good chance of seeing detail in frames if you are capturing at very high rates.

You should be able to change the frame rate of the saved file using something like the "AVI Frame Rate Changer Tool" described here - https://superuser.com/questions/45250/f ... f-avi-file (note - I've not used this tool, but it sounds like it would do the job).

Robin

dfisherows
Posts: 12
Joined: Fri Jun 09, 2017 4:39 pm

Re: All Sky settings

Post by dfisherows » Sun Oct 01, 2017 4:58 pm

Thanks for the info Robin.

User avatar
turfpit
Posts: 319
Joined: Mon Feb 13, 2017 8:13 pm
Location: UK
Contact:

Re: All Sky settings

Post by turfpit » Sun Oct 01, 2017 7:02 pm

I will try this out tomorrow on the bench with an ASI120MC and see what happens.

Dave

dfisherows
Posts: 12
Joined: Fri Jun 09, 2017 4:39 pm

Re: All Sky settings

Post by dfisherows » Mon Oct 02, 2017 5:38 pm

Will keep trying the AVI, but until then here is an example of a time lapse of the night sky using Sharp Cap and a ZWO ASI120MM-S using the PNG setting. Approx. 1250 images. Link is below.

https://youtu.be/APs_IzVlfPY

User avatar
admin
Site Admin
Posts: 1889
Joined: Sat Feb 11, 2017 3:52 pm
Location: Vale of the White Horse, UK
Contact:

Re: All Sky settings

Post by admin » Mon Oct 02, 2017 5:49 pm

Nice video :)

Just had a look, and it looks like PIPP (https://sites.google.com/site/astropipp/) can change frame rates when re-saving as AVI. You could also experiment with saving as SER (which has a timestamp for every frame) and then processing to AVI in PIPP.

cheers,

Robin

User avatar
turfpit
Posts: 319
Joined: Mon Feb 13, 2017 8:13 pm
Location: UK
Contact:

Re: All Sky settings

Post by turfpit » Tue Oct 03, 2017 9:20 am

David

I had a look at this as a limited test but enough to document what is happening. I think Robin will be able to expand on this. What I can say is that the capture settings you used are being interpreted by SharpCap as we expect.

The tests were carried out on the bench using an ASI120MC with wide angle lens, set at 1280 x 960 (maximum) with an exposure time of 30s.

1st test
A straight 60s capture. 30s exposure for 60s should give us 2 frames. When loaded into Autostakkert, the software reported 2 frames were loaded.

These were the settings used for the extended captures.
capture-settings.PNG
capture-settings.PNG (13.62 KiB) Viewed 517 times

So the expectation is using a 30s exposure - capture for 10 minutes (should result in 20 frames per capture), 6 captures (should result in 6 files).

These are the results:

AVI capture
AVI-files.PNG
AVI-files.PNG (26.46 KiB) Viewed 517 times
6 files as expected. The Length column of 00:00:00 - not too sure what that means.

AVI-in-PIPP.PNG
AVI-in-PIPP.PNG (19.62 KiB) Viewed 517 times
20 frames indicated but the fps is shown as 30. I think Robin has commented on this above.


SER Capture
SER-files.PNG
SER-files.PNG (27.46 KiB) Viewed 517 times
6 files as expected.

SER-in-PIPP.PNG
SER-in-PIPP.PNG (18.62 KiB) Viewed 517 times
20 frames indicated with a fps of 0.03. 0.03 multiplied by 600 (10 minutes) gives 18 frames - so about right.

Note the files sizes for both AVI and SER are around the same. When both types of files were loaded into Autostakkert, the software report 20 frames.

There seem to be lots of anomalies thrown up on forums concerning AVI files - a particular one being a size limit of 2Gb (sometimes). Also, historically, there seem to be different 'standards'.

The SER format seems much better defined and would certainly be a good choice for high speed planetary imaging where large files are produced. I always use SER now for video capture as with PIPP there are plenty of conversion options available. The SER Player is also useful as it reports file properties and shows a histogram if that option is switched on.

Hopefully this will help clarify what is happening (even if it doesn't fully answer your question) and demonstrate that SharpCap is working reliably.

Dave

dfisherows
Posts: 12
Joined: Fri Jun 09, 2017 4:39 pm

Re: All Sky settings

Post by dfisherows » Sat Oct 21, 2017 5:55 am

Thanks for all the info/help. Doing fine now that I understand it.

Maurits
Posts: 9
Joined: Fri Oct 20, 2017 3:16 pm

Re: All Sky settings

Post by Maurits » Sat Feb 10, 2018 8:15 pm

Sorry that I jump into this forum, but I am a bit in the same situation as the first poster. ;)

I have the ASI ZWO 120MM camera as my "all sky camera" and my only goal is to make timelapses :) (I have NEVER make one ...)
I have a lot to learn and this place give me the possibility to find help with the SharpCap software.

In the beginning I read:

How about this - set up your 20-30s exposure, then go to 'Start Capture'. In the start capture dialog

* Choose time limit and select a limit of 1:00:00
* Tick 'perform a sequence'
* Set the sequence length to 6 and the interval to 0:00:01

That should record 6 separate videos of 1 hour duration (about 1200-1800 frames) pretty much continuously through the next six hours. If you want a gap between the frames in the video (ie less frames, but without increasing the exposure) use the 'Maximum Frame Rate' control to select 1 frame every 30s or 1 every minute.


How do I make ONE video from the 6 sequences when I choose for the option "1 frame every 30s or 1 every minute".
When I try that, than I make a sort of a quick dia show, but that is not a movie .... (unless I use the max frame rate).

Ps

When I use the maximum frame rate , than I have a perfect video where it is speedup in Movavi Video Editor to a timelaps.

Thanks!
Maurits

MrAstroBen
Posts: 28
Joined: Fri Mar 16, 2018 12:19 pm

Re: All Sky settings

Post by MrAstroBen » Sat Sep 08, 2018 8:41 am

Adding to this subject.

I have started an all sky project. Main aim is a cloud monitor but will also play with some timelapse videos.
Dome. A £15 used cctv unit off ebay
Camera. Altair 290M although will try a colour one soon.
Usb 5m extender cable
Samsung netbook n130

Loaded sharpcap 3.0 , not sure if 3.1 will work on the netbook. Windows7 starter sp1 32bit?

Not entered my pro license yet. Have it installed on my two other capture laptops and pc. Assume there is a limit?

Results from first testing. Thick cloud so limited.

Manual settings, preview mode - will work as a cloud monitor/ scope position monitor perfectly. Next item to sort is an andriod remote desk control app. Aim is to be able to keep an eye on cloud cover via my phone from any room in the house. There are a few apps on google play store to try.

Timelapse test.

Set file type to auto. AVI was selected by sharpcap
Set to 8bit mono
1920x1080
Exposure auto (as conditions change through the night)
Focus was approx due to dense cloud.
Set frame rate to one every 2 seconds. In manual exposure mode using the 290M about 1sec exposures are ok using a 150deg cs lens. Anything more blows the histogram in my location.

Left running from about 11pm to 6.30am

Created an avi 7.44mins long @ 26gb.

Run from the netbook in Windows media player the video is under exposed. There are no controls in media player like sharpcap for brightness, contrast etc.

So, did sharpcap auto exposure make it too dim or does it need editing in another program? Anything in pipp i can do to stretch the avi or another simple app?

Thanks Rob
Attachments
20180907_184112_resized_1.jpg
Cheap dome, will make legs later. Room inside for extras
20180907_184112_resized_1.jpg (409.23 KiB) Viewed 21 times

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest