Jupiter - Moon Conjunction From Oregon, January 21, 2013

Started Jan 22, 2013 | Discussions thread
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RustierOne OP Veteran Member • Posts: 3,782
Re: Jupiter - Moon Conjunction, Computer Malfunction

harry cannoli wrote:

When people ask me what editing software to buy, I recommend Photoshop Elements. $100, and does 95% of what full-blown photoshop does.

Thanks for that information, Harry. For my astro and terrestrial work I've only used Elements - mainly just stretching the dynamic range with levels. But I should get an upgrade to a later version. First I'll be seeing how V2.0 works with my new Mac's screen resolution (1800 X 2800). Since none of the versions of Elements is optimized for the Retina display, there could be issues there. I'll just have to see what happens. I'll also be seeing how Aperture (which comes with the Mac) handles post processing needs, since it is optimized for Retina. I hope to order my new machine in two or three weeks when my wife lets me know when our savings are back up. I've had to pay for some dental crowns first.

Windows XP? The most stable version of Windows ever. Uses the NT kernal. Very stable. I'm now running win7. Not because I desired it, but because XP is obsolete, and is no longer supported by Microsoft. My workstation (XPS 700) has XP Pro installed. I have never, ever had a problem with it.

I like XP Professional as well. But I'm a bit worried as well because its support is going away soon. I believe I'll need Windows 7 for use on the Mac.

Going away soon? I haven't downloaded an XP upgrade in quite a while. I thought XP support was finished.

XP is still being supported - I downloaded some 40+ updates in 2012. Since 2008 there's been around 230 updates. That's how patched XP is. The latest patch came on Jan. 9, 2013. I hear that Microsoft has scheduled something like March 2014 to end support.

By the way, I've learned that with a third party software call Parallels Desktop (about $60) I can run XP and Mac OS in separate windows without rebooting. That will be cheaper than buying a Windows 7 upgrade for use with Bootcamp (part of the Mac OS package). Bootcamp requires reboots to go between operating systems

Curious, the NEX as prime focus with the scope, an eyepiece adapter, or with a lens?

I'm presently using the NEX at prime focus with the f/6.3 focal reducer on the C-11. With the APS-C sensor (15.6 X 23.4mm) by my calculations the 1760mm focal length gives an image size of 0.51° X 0.76° and 0.92° corner-to-corner. That's how I was able to get Jupiter and the Moon in the same image during the conjunction. I'm using a T-to-NEX adapter (from Telescopeadapters.com) along with a Celestron eyepiece port to T-thread extension tube.

f/6.3. Wow. Someday. I can get to 1344mm, but at f/8. For sharpness, I stop down one stop, so I'm at f/11. And the rig is heavy, and is on a tripod. I can't do Saturn. ISO 6400, 1/10 sec. A few snaps and Saturn is gone. I'm embarrassed to admit it, but most of the time I can't even find Saturn with the big lens. I can find it at 420mm, but that's about it.

The Schmidt-Cassegrain telescopes with focal reducer give a fairly fast aperture with adequate focal length. I think Meade sells something like an f/3.3 focal reducer which would give 922mm focal length. But B&H Photo warns "For CCD Use ONLY -Not used for visual observing, Not used for 35mm astrophotography". I don't know why the limitation. Not sure what it might do to image quality. Maybe it won't come to focus.

Acquiring Saturn with my Losmandy G-11 and getting it centered on the photo sensor can be a challenge. This is particularly so when using f/10 and eyepiece projection. Haven't done that since last spring for the image that follows.

I have also used a 1-1/4 inch to NEX setup that allows including an eyepiece in the tube for long focal length planetary imaging. That process is much more demanding than lunar imaging. Here's the only success I've had with the NEX-C11 combo:

C-11 f/10 w/ 9mm Plossl eyepiece projection, Sony NEX-5N, ~1/5 sec.

Stacked 150 of 410 jpg frames, 4 megapixels at 1600 ISO

That's fantastic! Wonderful detail in the rings, and you got it nice and big. Well done!

Thanks, Harry for the nice comment. I feel privileged to have gotten it all together for that image.

Here's another one using a Celestron-8 - afocal method: with 40mm Maxview eyepiece attached to the front threads of the zoom lens on an old Olympus C5050 (5 megapixel). That camera had more noise than the Sony NEX-5N.

Saturn and its Rings - 1.2 Mega-pixel Crop From Full frame.

This image was from a stack of some (unknown subset) of 360 frames. The image below is what the full frame before cropping looked like.

Saturn and Its Rings - Full Frame

Imaging the planets is much more difficult than with the Moon. The Moon just has a lot more to offer in fine detail. And its angular size requires a lot less focal length.

96% and then the error? Maybe stack fewer images, as you suggest. That's a shame, you almost made it.

I tried another run with the same 1394 images but with only 567 alignment points. It worked this time after 2 hours, 12 minutes of processing for alignment. I selected the best 125 frames out of the 1394 to stack. I saved that image before wavelet processing. I'm not sure how to go about re-using that image for further wavelet-processing versions. I tried keeping wavelet sliders very low to reduce blowing out the highlights. Here's the result, slightly cropped from the full 4-megapixel frame:

Gibbous Moon on Night of Conjunction with Jupiter, C-11, 1760mm f/6.3, 125 image stack, 1/1000 sec.

What follows is a crop of the above image :

Mare Imbrium from Plato (left) to Copernicus (right), stack of 125 frames, 1/1000 sec.


I look forward to having enough computer memory to run 16 MP images, rather than the 4 MP ones used for this stack. The above crop at 816 X 544 is starting to show pixels with much enlargement. I suspect that with higher camera resolution, I'll be able to more fully utilize the telescope's resolution capabilities.

I do most everything on my laptop. Dual core, 4gB RAM. DSS and RegiStax handle 18mP jpegs without any problem.

With the moon, do you see more with your eye than the camera resolves? Also, I'm curious. Do you use a mask to assist with focus?

Not having an eyepiece on the telescope when imaging, I've seldom had opportunity to compare the view. But when viewing with the eyepiece, any fine detail will many times be seen very briefly during moments of good seeing. And like many forms of observing, continued scrutiny will allow the eye-brain combo to build up a memory of what is present. The advantage of the the stacked image is that it preserves those brief moments of good seeing to build a sharper overall image than the live view will show. But there's something about the live view that the image doesn't record. It's just that with live view, you're looking at the real thing - not its image. On those rare nights of good to excellent seeing, both Saturn and Jupiter, as well as the Moon, look much better than any photo.

As for focusing, on the Moon "Peak Focusing" does a good job of indicating when optimum focus has been achieved. For the planets, I use a Bahtinov mask on a bright nearby star to nail focus. The mask doesn't work at all on the planet itself, since it's not a point source like the star. Peak focusing doesn't work well on Planets either, since much of the fine detail is of very low contrast. Here's a graphic on how the mask works when pointed at a star.Image of Bright Star with Bahtinov Mask

In any case, I've rattled on long enough! I hope some of this will be of use and an encouragement.

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Best Regards to All,

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