Webcam & Saturn - too bright? Apps to Drive Cheap Webcams?

[Logieberra]

Hey guys

Dabbled in webcam photography a few nights ago. When I looked at Saturn the image was too bright. I attempted to change the gain etc, but the software for this cheap webcam didn’t do much.

When I have used the webcam with my scope during the daytime the image is VERY sharp and can be bumped up to high resolutions (1280 x something). Should I have chucked a moon filter on it perhaps?

Are there programs out there that drive cheap webcams for astrophotography, with lots of nice settings?

The webcam is not identifiable, and has no particular make / model.

Cheers!

[[1ponders]]

G'day Logan. This is what you want from Stark Labs Craterlet (http://www.stark-labs.com/downloads.html)

Either that or you can download Virtual Dub and use the video recording function on that. Its actually very comprehensive but takes some time to find where all the setting are.

In you current situation, see if the settings are set on automatic (usually what blows the exposure out) and set to manual. Then set your frame rate to no faster than 10 frames per sec (5fps on nights of steady seeing) and your exposure for saturn usually around 1/25 sec. Faster if possible, but you need to balance your gain (start at around 1/2 - 2/3 max gain) so i don't think you will get much faster.


Good luck

[Logieberra]

That's Gold. Thx Paul. I'll give it a crack tonight and report back tomorrow.

Cheers!

[[1ponders]]

Good luck with it.

[Logieberra]

Paul

It’s taken a while to get the setup working. Made a few adjustments to the primary mirror holder etc, added a cooling fan, changed out the secondary hold with Brendan’s help, and got some collimation help from Anthony. Anyways, took my first shots of Jupiter on Saturday night from a dark site location, here in Canberra, with Barry Armstead’s (ASIGN) CASDAK group. Great night.

As per your suggestions:

· I downloaded Craterlet. Good stuff. Recognized my equipment J
· Tried to stack them in Registax. Nothing special came of it. And I have heaps of dust somewhere in the system which surely doesn’t help.
· I messed with the frame rates, anything from 3 to 20fps.
· Can’t remember what I did with exposure...
· And not sure that I can adjust the gain (there was no tab/setting)… will have another look in the menu and report back.

Anywho, here are the shots. Any suggestions?

Thx Paul J

[LeeSMaz]

What setup were u using?
Was it the 10" Newt or a Dob?
Cheers.
Lee.

[Logieberra]

See my signature block. 10" newt. Thx Lee, kinda nice to be able to use stuff from home for astrophotography! The webcam is nothing special...

[mswhin63]

All software relies on webcam driver having exposure control. Most webcam do not have exposure control and as most of the image captured is black the result is the camera automatically increases the exposure to compensate.

I have had no success with exposure on any webcam (even those with a manual exposure control) so instead I use filters to decrese visual exposure for my 12" DOB.

Need to clean your CCD/COMS sensor on the webcam very carefully.

[Logieberra]

There is a small glass cover/window in front of the CCD. Should I remove this as well? The dust may be inside this chamber.

Can someone please explain how I stack the jupiter video in Registax 5.1 ? I was 'very' roughtly polar aligned. The planet kept drifiting so I had to use the hand controller to center it often. I can't seem to stack the images with the alignbox. What alignment method do I use for a planet that jumps all over the screen?

I took a few more pics last night. Seems that my original pics a few months ago were not a good indication of the scope or webcam. While these aren't spectacular, it's still good to know that both the scope and cam have lots more to offer :)

No stacking, just single expsosures with the webcam.

[mswhin63]

There is a bit too much dust on the CCD to align properly, I recently cleaned mine after taking a few shot with loads of dust on the CCD, and Filters. I cleaned them thoroughly while the scope was sitting in the front of the house along with my computer. Once the dusts was cleared the images came through better in comparision.
The dust creates false alignment in Registax and AVIStack.
Dont remove the glass though, would be a pig to place back on.

To align planets first visually check each frame till you find the clearest image (Use this as a reference) then select "Centre of Gravity" check box in Registax "Align" Tab. Can't go wrong with that. The rest use default while learning.

With webcams the pixel updates are slower than industrial or astro CCD cameras so with atmospherics the change on the image will slightly blur more than the specialised cameras. With really good seeing though it maybe possible to get good images.

My latest images of Jupiter with a webcam were aligned as mentioned above although I have continually poor to moderate seeing from my location. The image was taken after dust was removed - http://www.iceinspace.com.au/forum/attachment_browse.php?a=81694

[asimov]

G'day Logan.

How are you going with all this? I realize this is an old thread. The dust, yeah, if the alignment box happens to pick up on a spot it'll then probably try to track the dust mote instead, & then it'll lose that alignment & lose the plot altogether. Make sure you use 256 pixel size box, & align on one of those white barges in one of the belts. Ordinarily if the alignment box is covering the planet it's better & more accurate. Bigger; more accurate; but slower.

I've never used 'align using center of gravity' EVER, so can't comment there. In tracking settings, make sure 'track object' is ticked. Untick 'predict track' tick the other 2 (misalign warning/ignore misaligned frames.) Use 'Gradient2' & start out at 96% lowest quality. Once aligned you can change the lowest quality settings to a different percentage to give a different sized stack.

This'll do for starters lol.

[Logieberra]

Thanks for the pointers Asimov.

I took some data on Monday 11 October with my new SPC900NC webcam. Had a fiddle with Registax 5.1 tonight and it's SOOOOO much better then before :) I'm looking forward to using this cam heaps over the summer months - when I'm done with uni :)

[erick]

Those look like quite nice initial results, Logan. I think you are going to have fun as your experince builds. And you may get a magic night of great seeing!

[Logieberra]

I dug out my old webcam that my dad gave me. It is capable of 1024x768.

When I compare the live video footage of this vs. the Philips SPC900NC the old one looks better! It also provides a BIGGER image scale vs. the philips.

I would really like to test it again, but I can't get rid of the 'dust'. After using an air blower (no compressed air) the spots remained. So I hooked the cam up, put the cover on and it turns out that the spots can still be seen in pitch black! Dead pixels right? Check out the pic.

Is there a way to fix these, or should I just image around them? Shame, for a $10.00 webcam the live footage is superb...

Logie.