Cameras for viewing

[bsercombe]

Excuse the stupid question...

I have a VC200L (8 inch F10, though I do have a reducer to F6.6) on a CG5-GT. I'm interested in seeing what display I can get from a webcam mounted to view through eyepieces.

Obviously I'm not wanting to view faint DSOs, mainly planets and stars (binaries if possible) in realtime. Can anyone recommend a webcam or similar for this kind of thing? Obviously I'd have to hand-make a frame to keep the eyepiece and camera correctly aligned.

Thoughts & recommendations (including that's a damnfool idea!!) welcome.

[rogerg]

This is what you really want:

http://www.myastroshop.com.au/guides/gstar/index.htm


... but it depends on what your budget is, as that is more expensive than a webcam.

Roger.

[jjjnettie]

Hi Brad,
I'll jump in first to recommend the Gstar-Ex video camera.
http://www.myastroshop.com.au/guides/gstar/index.htm
It would suit your purpose well AND you'll be able to observe the faint fuzzies too.
With this camera I can view the Horse Head nebula in realtime through a 100mm cctv lens.

[jjjnettie]

Beat me to it Roger.

[Dennis]

Hi Brad

To use a webcam to take pleasing images of planets and multiple stars, instead of reducing your focal length via a reducer/corrector, you will need to increase it with a Barlow lens to reveal nice detail on e.g. Jupiter and Saturn, as well as achieving a nice separation between multiple star components.

I use the DMK21AF04 mono and DBK21AF04 colour CCD cameras; both have a chip at 640x480 pixels. For colourful double stars, I have used the DBK (colour) camera at the prime focus of a Tak Mewlon 180mm F12 as well as using a x2 Barlow lens and it gives excellent results.

Here are some links to a few images:

http://www.iceinspace.com.au/forum/attachment_browse.php?a=28064
http://www.iceinspace.com.au/forum/attachment_browse.php?a=28269
http://www.iceinspace.com.au/forum/attachment_browse.php?a=28279
http://www.iceinspace.com.au/forum/attachment_browse.php?a=29041
http://www.iceinspace.com.au/forum/attachment_browse.php?a=29579
http://www.iceinspace.com.au/forum/attachment_browse.php?a=29581
http://www.iceinspace.com.au/forum/attachment_browse.php?a=29580

The webcam should be fitted with an adapter that allows the webcam to be inserted directly into the Barlow, or eyepiece holder, when used at prime focus. This means that you should not require a custom adapter to clamp the webcam.

Cheers

Dennis

[Dennis]

Hi Brad

Having just seen the replies from Roger and Jeanette, I thought that I should note that all the DBK images in the links I have provided are not “real time” images. That is, they are the result of stacking several frames (sometimes 100’s) to produce the final result.

Cheers

Dennis

[bsercombe]

Thanks for the quick response! I'm more interested in viewing than stacking images into photographs, still- if the capability is there who is to say I won't give it a try. I'm more likely to satisfy some apeture fever than spend a lot on photography gear.

Dennis, those are some awesome double star images! I really appreciate seeing those so thanks for linking them. So you removed the 2ndry of your Tak to mount the camera?

Do the DMK cameras produce similar real-time images to the Gstar or are they capture only devices? I'm thinking that the GStar is probably what I'm looking for.

[Dennis]

Hi Brad

No – the Tak wasn’t modified at all. I simply removed the eyepiece from the focuser, inserted a x2 or x2.5 Barlow and then inserted the DBK webcam. Here is a link to the D*K series (http://www.astronomycameras.com/en/products/)where you can see the 1 ¼” adapter tube on the front of the camera body (blue cube) which simply slides into the Barlow.

The DMK and DBK do show you very nice live images, but you are viewing these as a movie; that is, you are seeing a real time image at say, 15 frames per second, 5fps, 30fps etc. depending on setting.

So, for those doubles, I recorded a movie file (e.g. Antares.avi) of say, 1500 frames and then later at my desk, used a program to select the best quality frames and stacked them together to produce the final image (automated).

Each single frame will have the multiple stars nicely visible, but will also have some “noise” or a grainy appearance. By stacking several 100 of the best frames, the quality of the double star image increases markedly and the noise is also reduced dramatically giving a nice, smooth final image.

So, when you are viewing live, the doubles and their colours are visible, but the background may appear grainy, especially if you need to increase the Gain (sensitivity) to record the stars adequately.

I think that the GStar-Ex actually “stacks” or “integrates” the displayed image in real time, so what you are looking at, is a “live” image that is a stack of several frames? I’m sure a GStar-Ex owner will correct me if I am wrong here.

Cheers

Dennis

[bsercombe]

Ok, after reading manuals etc. I'm looking hard at the Gstar now, the DMK looks great too but I'd like the realtime integration capability.

Can anyone recommend a capture card for laptops that will work well with he Gstar? I'm going to want to run this from a dark site.

Rumor has it that jjjnettie has some stuff up on the web about her Gstar work. Love to see it if it's there!

[jjjnettie]

Hi Brad,
I use a Belkin video capture adaptor which connects from the Gstar to a USB 2 port on my PCMCIA card.

[bojan]

I do not have direct experience with this product, but, just in case.. here it is:
http://cgi.ebay.com.au/EASYCAP-DC60-EasyCap-USB-2-0-Video-Adapter-With-Audio_W0QQitemZ220372762378QQcmdZVi ewItemQQptZPCC_Video_TV_Cards?hash= item220372762378&_trksid=p4634.c0.m14 (http://cgi.ebay.com.au/4-Channel-USB-2-0-DVR-Video-Audio-Capture-Easycap_W0QQitemZ220369956517QQcmdZ ViewItemQQptZAU_Components?hash=ite m220369956517&_trksid=p3286.c0.m14&_trkparms=72%3A975%7C66%3A2%7C65%3A 12%7C39%3A1%7C240%3A1318)

The vendor has a strange price structure (cheap item, but expensive postage)... ;)
Still, it looks reasonable enough.

[33South]

I use this one, even works with Vista.

http://www.citysoftware.com.au/Browse/f7c730f56626409b9cf7957641829980001 ItemDetail.aspx

If you dont want to capture the image stream to get the best live display (with the GStar) you want to use a high res TV type monitor not a lappy. In fact as the GStar has two video outputs you can do both at the same time.

[bsercombe]

Thanks everyone- I'll probably use a USB device- logic being that it should use less juice than PCMCIA. I'm looking to see if I can find one that will do the full 768x576. Wonder if we can push the Gstar manufacturer to move to USB rather than serial for control functions...

[netwolf]

Hi Brad,

This is a more expensive version of the GStar. It has been modifed for improved performance. As sucn it is also more expensive
http://mallincam.tripod.com/

I have also used a Stellacam, whcih i borrowrd of my friend with a B/W Security TV screen. I used this setup back when I had the dob and Lx90. It's amazing even in the suburbs what you can see in real time on this that your eye could never see.

There are people who now broadcast there video online so others can see.
Essentially these cameras do a internal frame integration, kind of like stacking frames. However the stacking doene this way does not intelegently filter out bad frames (due to atmospherics etc). But this method still provides a very good image for real time display.

There is a section on the US CN forums dedicated to this type of observation and imaging.
http://www.cloudynights.com/ubbthreads/postlist.php/Cat/0/Board/VAA

Also see here for Imaging results.
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/2050552/page/0/view/collapsed/sb/5/o/all/fpart/21#Post2863781

And the Online streams from other Video observeres. Skychannels.
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/2210710/page/0/view/collapsed/sb/5/o/all/fpart/1



Regards
Fahim

[bsercombe]

Thanks netwolf!! Looks like I have some more manuals to read :)

[tiggere]

If your wanting a cheaper option the Philips SPC900NC with a Agena Adapter will do what you want...I have around $65 total in mine...conversion takes all of a minute and it slips in the EP holder...software I use is QCFOCUS and WcCTRL...I normally shoot 10x30 sec vids then stack them in Registax...

Here's 15600 photo's stacked and stitched of the moon...
http://i36.photobucket.com/albums/e17/Flying_Solo/Astro/moon2.jpg

Jupiter...
http://i36.photobucket.com/albums/e17/Flying_Solo/Astro/Jupiter61508.jpg

Quarter moon (1500 pics stitched)...
http://i36.photobucket.com/albums/e17/Flying_Solo/Astro/moonbandw.jpg


These were shot through a 6" SCT with no barlow...a powermate 3x would be a welcome addition to my house...although the crummy skies around here don't offer very good viewing...the heat rising from the neighboring houses can be pretty bad also...