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Old Sep 18, 2004, 8:20 AM   #11
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Yeah, I'm using a telescope for almost all the photos there. There's only one on there where I took the shot without one, called "Ground Shot", of the moon. I never bothered to invest in an electronic drive or tracking system since my camera is a limiting factor. I'm not going to be able to take anything that I consider nice with it. I've thought about getting the Digital Rebel and then buying a drive, but I'm not yet sure if it's worth the $$$. It is indeed an expensive hobby and I do limit my budget so as not to get carried away with it.

All photos I took use the smallest f-stop and ISO (50-100) I could get, which is about f/4.8 at 3x optical zoom (zoom is necessary to prevent vignetting with the eyepiece). Objects like the moon, while nice and bright, actually get very dark once you zoom in to much on a small telescope. At 90x or less, I'm safe to use a shutter speed of about 1/125 to 1/320. At 180x, I have to risk using a shutter speed of 1/10 to 1/5 which is bad because of atmospheric turbulence at that magnification (blurry images!). It's a lot worse for Jupiter and Saturn. That's why I resorted to using movie renders and then digitally group them together afterwards to get a brighter, proper image.

The only time I use digital zoom is when I need to fine-focus my telescope. It's very handy in that respect. For regular night sky shots, the 17x zoom would be more than enough to capture space objects. Almost all shots taken of star clusters, nebulas, galaxies, comets, and zodiacs are taken with low magnification settings, which is 20x to 36x (depends on your telescope). In the right environment, you should be able to capture a lot of nice stuff. You can also stack your 15 second images to produce a 1-minute long exposure; however you'll need an electronic drive for something like that.

White balance could be the culprit in your yellowish moon shots. I've been fortunate enough thus far for the camera to auto-correct the issue, so I don't know for sure. A manual white balance setting on a bright object before shooting the moon should fix it though.
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Old Sep 21, 2004, 11:47 PM   #12
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I was reading these posts and took some moon shots to see if I could do it.

I am using a Panasonic Lumix DMC-FZ20.

This is real cool stuff.

I am just a beginner, but here is a moon shot at full zoom at f2.8-1/250.
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Old Sep 23, 2004, 12:23 PM   #13
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Good job.

Fun, isn't it? :-)

Now try capturing some stars... a lot harder, but still rewarding.

Regards,

Tom, on Point Pelee, Canada
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Old Oct 30, 2004, 5:41 PM   #14
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Tom Overton wrote:
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Living in Winnipeg, you would have some excellent opportunities for night shots. When I lived in northern Ontario, we would get some spectacular displays of the Aurora Borealis.
Where in Northern Ontario did you live?
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Old Oct 30, 2004, 7:18 PM   #15
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Hi there;

Well, I grew up in Petawawa Ontario, in the Ottawa Valley, which is fairly "north" compared to the sunny south, and I began my teaching career in Blind River, which is on the north shore of Lake Huron. I don't miss the cold, but I miss the bright, snowy winters. (not enough to move back, though):?

Regards,

Tom, on Point Pelee, Canada


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Old Nov 1, 2004, 7:43 AM   #16
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Ahh ok i thought you meant Northern Ontario as in Thunder Bay/Kenora/Sault St. Marie...
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Old Nov 1, 2004, 12:24 PM   #17
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Capturing stars in the evening sky is best accomplished with a wide lens, not a telephoto. The general rule of thumb on star exposure to avoid streaking due to the rotation of the earth - divide the focal length of the lens into 600. This will yield an approx. maximum seconds of exposure before star streaks will occur (unless you want them). For example, if you are using a 35mm lens for an evening sky shot: 600/35=17 So, 17 seconds would be the longest exposure to use and capture motionless starry skies.
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Old Nov 1, 2004, 10:14 PM   #18
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Hi Flint;

Thanks for the formula. It's a little harder to figure when using a digicam where you don't always have a clear idea of your focal length but it is certainly a good guideline. My Kodak dx6490, which has a 35mm equivalent of 38mm clocks in at just under 16 seconds, which is the slowest shutter speed for the camera.

Correct the following logic if I'm way off, but if I'm not totally mistaken, my wide-angle lens effectively reduces the focal length by a factor of 0.7 or 26.6mm. Would this give me an effective shutter speed of 22.5 seconds if my camera were capable of such speeds?

Regards,

Tom, on Point Pelee, Canada

P.S. to Dave... I know true northerners scoff at the mid-north. Blind River is about an hour and a half East of Sault Ste Marie, so I don't feel too bad. I do have some cousins in Wawa, and there is a history of Dawson City in the Yukon which is dedicated to my uncle... but now I'm bragging. :-)
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Old Nov 23, 2004, 11:52 AM   #19
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Thought I'd give a moon shot a try. Here's mine, shot with a Canon PS S1IS at ISO 50, f 7.1, 1/250 using a TC-DC52B tele-converterat full optical and digital zoom(which amounts to 51.2X)
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Old Nov 23, 2004, 1:41 PM   #20
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I have done some moon shots with my Canon S1 and a crystalvue 8x32 spotterscope; this combination gives me a total zoom of 80X: 10X fom the camera's optical zoom and 8X from the scope; the image of the moon fills the frame at 2048x1536; effective focal length (35mm standard)= 38x80=3040mm; digital zoom, although very usable on the S1 clearly produces deterioration of picture quality; one of my moon shots is attached; photo of my setup in following post


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