Farewell, Jupiter. Hello Saturn.

[SlyReaper]

So... I've been trying my hand at a spot of astrophotography.  I have a 5 inch newtonian, and am using a webcam to take the photos.  My first lot looked very purple, and it was pointed out to me that I need an IR cut-off filter.  So I got one, and here are my first results. 

Jupiter is getting closer and closer to the sun as the weeks move on.  I can only capture it during twilight now, so not as good as I might otherwise have managed.  Soon, it won't be an evening object any more, and it'll be gone until next year. 

I took another shot, this time deliberately overexposed to show three of the moons. 

It is maybe a little sad that Jupiter is fading now, but in its place, Saturn is now an evening object, rising earlier and earlier in the evenings, but still late enough to be in true night.  That thing is incredibly difficult to find with the webcam, because the one I use seems to magnify the image to a ridiculous degree, with a very narrow field of view.  But on Monday night, I finally acquired it.

Super happy with that one.  Nowhere near as spectacular as what I've seen others post here, but I think that's not bad for a 5 inch scope with a £15 webcam.  A yellow fuzzy ball surrounded by a yellow fuzzy ring, it's my first Saturn picture and I'll probably treasure it more than any subsequent Saturn shots I manage with more capable equipment.

Speaking of more capable equipment, I'm thinking http://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-250px-flextube-goto.html with http://www.firstlightoptics.com/imaging-source-cameras/dfk-21au04as-colour.html.  Anyone had experience with either of these two?  Not after DSOs at the moment, I'm primarily after planets. 

Just for good measure, here's a shot of some moon craters.

See what I mean about the high magnification and narrow FOV?

[Kropster]

Nice pics.

The super magnification and narrow FOV are due to the fact that the webcam chip is tiny and only samples a small part of the image.

Sure makes getting a tiny planet onto it difficult!..... even more so if you use a Barlow lens too.

[Stargazer33]

That's a very good start. Jupiter is getting very low now and the extra atmosphere that you have to observe/image through makes it a difficult capture.

When you say you used a web cam to take the photos, do you mean that you took a single frame?

If so try taking a video of anywhere between 1000-3000 frames. Find out what the fastest frame rate you can use before your web cam starts to compress the data in order to keep up. My old Philips SPC900NC could only run at 10 fps which limits the amount of good frames you can capture in those fleeting moments of good seeing.

You want to limit the time with planets, especially Jupiter and Saturn as they spin so fast, unless you are going to use something like WinJUPOS to de-rotate the images. Then use PIPP to align the planet in the centre of each frame and limit the number of frames to say the best 25% and then stack them in Registax, or AS!2. You can then use the wavelets feature in Registax to bring out more detail.

Can't comment on the scope or CCD but it looks serious kit!

[SlyReaper]

That's a very good start. Jupiter is getting very low now and the extra atmosphere that you have to observe/image through makes it a difficult capture.

When you say you used a web cam to take the photos, do you mean that you took a single frame?

If so try taking a video of anywhere between 1000-3000 frames. Find out what the fastest frame rate you can use before your web cam starts to compress the data in order to keep up. My old Philips SPC900NC could only run at 10 fps which limits the amount of good frames you can capture in those fleeting moments of good seeing.

You want to limit the time with planets, especially Jupiter and Saturn as they spin so fast, unless you are going to use something like WinJUPOS to de-rotate the images. Then use PIPP to align the planet in the centre of each frame and limit the number of frames to say the best 25% and then stack them in Registax, or AS!2. You can then use the wavelets feature in Registax to bring out more detail.

Can't comment on the scope or CCD but it looks serious kit!

I took 3 minute videos at my webcam's maximum framerate of 10fps, then stacked the best 5% of frames. 

Yes it's serious kit, but I find myself in the enviable position of having money to spend at the moment.  If I don't spend it on a big treat for myself, it'll end up getting spent on beer and snacks over the years.

[Pete Presland]

nice start, to your imaging! the scope when well collimated, would produce some fine images and as it tracks will make the job a lot more comfortable. not so sure about the webcam though, the DFK 21AU04.AS Colour is quite old now and for £269 you can get a better camera. matybe something like ASI120MC  http://www.365astronomy.com/zwo-asi120mc-colour-13-cmos-usb20-camera-with-autoguider-port-p-3536.html or QHY5L-11 http://www.modernastronomy.com/camerasGuider.html both very highly regarded!

[SlyReaper]

Are they better? I notice they're CMOS, not CCD. Does that make much difference? When researching th DFK, it seemed that was also very well regarded, getting a 92% score from Sky At Night magazine. You may be rright and I've been looking at old information.

[Kropster]

I think modern CMOS, especially ones designed for astro type work are okay. Technology marches on.

[SlyReaper]

Well, I've more or less committed myself to buying that 10 inch guided dob now.  I'll see what I can get with the webcam, and then upgrade to a QHY5L-11 or something to see the difference.  Off topic, but who the hell names these astro cams?  "DFK 21AU04.AS" and "QHY5L-11" are terrible names. 

[Pete Presland]

the two cameras i have mentioned especially the ASI have rally been making the headlines in recent years, google either and see the quality of images they are truly inspiring!

[PeterCPC]

If it's any use I have attached an image taken with the DFK which i took last year through my CPC800. Nice to see what it can do.

Peter

[SlyReaper]

That's awesome.  That's in an 8 inch scope?

Well, I've gone and done it.  I've dropped a grand and a half on the 10 inch computerised dob, the ASI camera and a couple of miscellaneous gubbins.  Can't wait for it to be delivered.

[Pete Presland]

i dont think you will regret it, space cowboy on here http://stargazerslounge.com/topic/216864-saturn-may-15th-good-seeing-again/ is using a very similar set up.

[SlyReaper]

I'd love to get images like that, hence the new kit.  I don't think I'll get as clear an image as that though.  He was using a mono camera as well as a colour one, and combined the images; I'll just be using a colour camera.  Sounds like he had exceptionally good seeing as well.  I'd have to travel to find a good spot to take pictures from, because my house is in a moderately light polluted area and is at very low elevation (any lower and I'd be breathing salt water).

This big scope will mainly be for viewing sessions planned in advance.  I'll have to wait for perfect weather, find a dark sky spot at high elevation, and set everything up before sunset.  And then hope random rascals, miscreants and scallywags don't murder me for my laptop.  Will keep my current 5 incher for unplanned viewings, for when the forecast said cloud and yet it turns out to be clear. 

By the way, what does LRGB stand for?  I've seen it mentioned in a few places, but never explained.  RGB is red green blue, presumably for using a mono camera with a filter wheel, but what's the L?

[Pete Presland]

L is the luminance channel.

[Pete Presland]

light pollution is not going to have much affect on your planetary imaging. it will be affected much more by atmospheric conditions and local conditions such as heat rising from structures.

LRGB imaging is as you said red, green, blue, the L is a non coloured channel taken just using a I/R filter it normally contains more detail and is added to show a sharper image. i am sure you get some fine images even with an OSC (one shot colour) camera.