I'm getting started in trying webcam astrophotography and discovered RegiStax.  I have a D-Link webcam available and have been working on getting the process down -- from video capture to input into RegiStax.

Starting with Microsoft's Windows Movie Maker.  Got a video capture to an AVI file setting any options I could find that removes compression or included audio.  RegiStax won't have anything to do it.  Something about invalid AVI stream.

Further searching finds WinDV.  Fine.  Firewire only.  Laptop I take out to the telescope has no firewire ports -- only USB.  WinDV abandoned.

Next found VirtualDub.  Downloaded and installed latest stable version of VirtualDub (proper version?).  Reviewed Options/Preferences to remove any audio stream and compression.

RegiStax doesn't like this .avi file either.   I'm running RegiStax version 4.0.1.1 on Windows/XP SP 2.

I'm stuggling just getting an .avi file into RegiStax.  The VirtualDub test ran a capture for ~30 secs that resulted in a ~140MB .avi file.  This seems to be well within any AVI file size limits.

When loading this file into RegiStax (via the Start tab) RegiStax fails with the message:

   "Failed to start AVI decompression"

can someone please comment on exactly what RegiStax wants in terms of a webcam input file?  Should audio be excluded in the .avi file?  (i.e. does RegiStax care?)  Can RegiStax tolerate compression used in the AVI file?  (i.e. should any compression be turned off in the video capture?)  [during the VirtualDub capture process the "status" frame on the right showed a compression ratio of 1.3:1 in the Video section.  I am unable to get this down to 1:1 or off altogether.  Do I need to?  And if so, how?]

I appreciate any help in understanding how to properly capture a video stream for RegiStax.

If you prefer to contact me directly via email you may use rmerritt1@gmail.com.

Thanks in advance,

r.s.

 

  to the forum Rob. The trick I've found with Registax, is to save your avi from Virtual Dub as uncompressed, and use the "Save old format avi" option. Registax has no problem opening the file then. I just did one that turned out to be 4 GB's in size, and Registax opened it without any problem. So evidently, Registax doesn't care about the size of the file either.

Good luck! 

Kevin Bozard:

... I just did one that turned out to be 4 GB's in size, and Registax opened it without any problem. So evidently, Registax doesn't care about the size of the file either.

Well, yes and no. There is a good deal of info on the file-size limitations at the Registax Yahoo Group. It seems to depend on the version of Windows you're running and how your PC's memory is set up.

I have been able to use R3 and R4 with AVIs up to about 2Gbytes without a problem on systems with Win2000 and XP. My Win2000 system had only 256M RAM, so it was very slow, but it would still process such files. My XP system had 4G RAM and never had a problem with files up to about 4G in size. I haven't tried larger files.

I occasionally load multiple files simultaneously and most of those have been on the order of 2G.

I do have a problem with the XP system and multiple DSLR files. I have been able to process as many as 52 6-megapixel images simultaneously, but the system choked when I tried to load 60 into either R3 or R4.

I haven't tried either of these capacity tests with R5 yet. My new system is Vista 64-bit, with 4G RAM.

For quite a while the Yahoo group reported many problems with AVIs over 2G as a "Windows limitation." I don't know if that problem has been resolved.

 Good points Jeff. I should have clarified that I just opened the file in Registax, but didn't try to process it. It very well may have hosed up the operation because of it's size. My main point was to help Rob get the file to open in Registax.

Yep, I agree. VDub is the handiest utility I've discovered yet for doing that.

 Kevin,

Thanks for your reply.  I didn't see these options until you pointed them out.  My latest test with ~15 sec capture and saving the original capture .avi file to a seperate .avi file using the "Save old format avi" option produces the same failure in RegiStax.

In the Select video compression dialog window I have "(no recompression: I420)" set.  The only other options shown are Microsoft MPEG-4 Video Codec V1 and Microsoft MPEG-4 Video Codec V2.  Am I correct in assuming that neither the 2 Microsoft codec options would be appropriate?

In the capture mode window, after I terminated the capture, the various stats over on the right showed, among others:

   Frames captured   413

   Total file size         45.3MB

   In video section

      Average rate    29.66376 fps

      Data rate          3338KB/s

      Compression ratio    1.3:1

      Avg frame size     115200

      Frames dropped    3

      Frames inserted    8

  In Audio section

     Size      0 bytes

     . . .

  In Sync section

     VT adjust     +0 ms

     Current error    0 ms

 

Is there anything in these statistics that suggest other options that should be set to produce an AVI file that RegiStax likes?

 

r.s.

 

try splitting that and try 200 frames- i know it sounds stupid when people load 2gb info into it- but i have XP with 4GB memory and have trouble loading 500 frames into any version of regis

Well, first off, my sincere thanks to all who took the time (and pain? :) to assist me.  I’ve managed to solve the problem, and it never occured to me that a Windows emulator would be the root cause.  In my travels over the Web to try and find further info on this RegisStax failure I came across a note from Ken Hough at http://www.astronomie.be/registax/linux.html that contained the key (in my case) comment:

“wine REQUIRES that AVI files are recorded as RGB. If a YUV encoded file is presented, an error message will be given that will include:

"Failed to start AVI decompression"

I failed to mention in my original posting that I use my Linux server as my astronomy archive and that I’m running RegiStax under wine on Scientific Linux/KDE.  I expected a Windows emulator to be the last source of fouling RegiStax; until I found Ken’s notes.

For anyone new to webcam and RegiStax that may be running into this same message, I offer my notes below:

VirtualDub Notes

Main Window
-----------
 o File | Load Processing Settings...
 o Video | Direct Stream Copy
 o Audio | No Audio

 o File | Capture AVI...


File Capture Window
-------------------
 o File | Set Capture File
 o Video | Set custom format...
   - Frame size -- 320 x 240,  Data format -- 24-bit RGB[1]


After Capture
-------------
 o File | Open video file...
 o File | Save old format AVI...  (select separate file)
    [it is this separate file that is input to RegiStax]

exit VirtualDub


[1] it is Wine that limits avi files to RGB only!
    Frame size depends on camera -- experiment


In the interest of making this process more robust and easier for new people getting interested in webcam astrophotography and RegiStax, the Ken Hough note and my outline would be a nice Appendix entry for the RegiStax User Manual.  Does anyone know who “owns” responsibiity or access to the User Manual, a contact person, that I could work with to include this for the Linux community?

Thanks again,
r.s.
 

Contact Cor Berrevoets at registax@gmail.com

I'm sure he could lead you in the right direction.  

 Hi, I read this guide, it's really helpfull, but i couldn't find a stack for meteors shower. I have to write an official report for Perseids meteor shower in 2008. I want to make a collage from 6 pictures in wich are cought meteors. Registax stack them, but he makes some changes in the contrast and some other, so the meteors that I want to be shown generally are gone or are very pale and you can't even see them. I've tried an automatic and manually regime but no result. So do you know if Registax has a special option for meteors stack or to give me a tip how to do it better. Thank you in advance. :)

This will only work if the camera which made the photos was tracking the stars and aimed at the same point in the sky for all the pictures ... otherwise, the stars in the background won't match up.

If those conditions were met, then you can manually add one image at a time to separate layers in Photoshop and combine the images.

Don't use Registax for this, as it works to minimize the difference between the images (the meteor trails) and will make the meteor trails dimmer with each image you add to the stack. The Photoshop method of layers works to maximize the difference between the images (which is the meteor trails).

All pictures are taken in the radiant, no other, so the stars match. But what shall I do on Photoshop, I mean to add image by image, it's going to be too hard matching all the stars in one. Or is there any function, that I don't know about, again? I remember there was a funcition for mozaik, but I don't think it will be helpful. (I've tried sth like that, I took pictures of the moon with big zoom of every part, then I make a one photo of thoose 24 pictures or parts with the help of photoshop, so do u know sth about a similar function?) Sorry for asking but I don't know what I really should do.

In Photoshop Help, look for "registering layers" ... that's what you'll be trying to do: register one layer atop another.

Other programs like DeepSky Stacker might be an easier way to do this ...

Thanks a lot! :)

chipdatajeffB:

In Photoshop Help, look for "registering layers" ... that's what you'll be trying to do: register one layer atop another.

Using layers is one way of doing it in Photoshop, but that can be seriously time consuming. Photoshop CS2 and latter has automated scripts for photomerge which is great for panoramas, then another for Merging images into an HDR which might work for DSO Astrophotography. Photomerge I have used, Merge to create a HDR image I have not, yet, so I don't know how well it will handle any misalignment in the stars. Then there is Dark subtraction to consider also, But shouldn't be too difficult using layers.

When I get the time I am going to take some of my old image data and play around with that.

on edit: I don't know about the other version but I see CS4 also has a Stacking script.

Hi, that link step-by-step guide doesn't work, anybody can give it, cause its really helpful

Sand Saref:

Hi, that link step-by-step guide doesn't work, anybody can give it, cause its really helpful

That link is outdate and referred to a older version of RegiStax. You can download the manuals for version 3 to 5 from http://www.astronomie.be/registax/

You can find the manual by clicking the download link on the top of the page, you can also click the individual User articles under "RegiStax In Depth".

You can also refer to the following thread within this forum paying attention to the posts from chipdatajeffb:

http://cs.astronomy.com/asycs/forums/t/31238.aspx

http://cs.astronomy.com/asycs/forums/t/34899.aspx

If it's deep sky objects you want to stack then you will be better off using Deep Sky Stacker.