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Old 20-November-2006, 06:35 AM
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AutoClub AutoClub is offline
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Default New star trails image, but no Leonids

This is an 11x17 crop from an original stack of 30 images. The 30 original camera images are each 1-minute exposures taken with a tripod-mounted Canon 20D equipped with a 16-35mm Series L lens set at 16mm focal length, f/2.8, ISO 3200. All was well at the beginning of the exposure sequence. However, a few minutes into the image acquisition, the camera lens began fogging. Since I had used a remote shutter release set to take the 30 1-minute long images, pausing only 1 second between shots, I had left the camera unattended. As a result of the fogging, the later images are more diffused. However, upon stacking the images with the program Image Stacker, I was pleasantly surprised that the fogging effect apparently enhanced the color spectrum of the stars. The camera was pointed in the vicinity of Cassiopeia, and the brighter cluster of streaks near the lower right hand part of the cropped image is actually the Pleiades, or The Seven Sisters, Messier M45. M31, the Andromeda Galaxy is visible in each of the original images, although slightly sharper in the earlier ones because of the moisture accumulation on the lens surface. With the camera lens set to 16mm focal length, M31 appears very tiny, but it is apparent nonetheless.

Images were taken at Lake Cachuma on the evening of November 18th, 2006, starting at 9:12 p.m. PST. While waiting for the Leonid Meteor Shower to appear, I decided to set up my camera and tripod to try to capture something. Although I only saw 1 or 2 very short meteor streaks, some friends I was with saw probably more than a dozen in the time we were there. They were fortunate enough to be lying still, while I was moving around and only occasionally looking at the sky. Unfortunately, I have not found one Leonid streak in any single image I captured that evening – bummer! But, at least the weather was very warm, and the sky dark enough that the Milky Way was instantly visible shortly after 6:00 p.m. PST. It was a very enjoyable evening overall.

Lake Cachuma is accessible from Highway 154, and is inland from Santa Barbara, California. Because of the dark skies close to home (approximately 100 miles one-way), I definitely want to return with a telescope that’s tracking to get some better pictures. However, I was very pleased with these results, despite the dampness that crept into the images. Enjoy!
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Old 20-November-2006, 09:07 AM
djellison djellison is offline
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Lovely image - what software did you use for the stacking?

I took 250 or so images from 0027 to 0257 on Leonid night, not the 'peak' but the best I could do automatically - it'd be interesting to stack them.

Doug
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Old 21-November-2006, 04:02 AM
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Default Software used to stack images

Hi Doug - I use a software program called Image Stacker. I found it at: http://www.tawbaware.com. This is one of many programs offered by Max Lyons, who is a panoramic image guru in my book! I use his PTAssembler program for stitching muliple (panoramic style) images together. It is great!

There's a link to Image Stacker from the Tawbaware main page. It's a shareware program, and the $17 I paid to register it was well worth the price. It offers different options, from stacking, averaging, and brightening of images, plus even dark frame subtraction (which I haven't used yet, but need to).

Thanks for your comments and question.

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Old 21-November-2006, 04:58 AM
Gob332 Gob332 is offline
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very nice image. I went out last night in Northern Minnesota to attempt picking up some sky images for the first time. I was not expecting to see any Leonids, however to my surprise I saw two fairly visible meteors. In addition, while taking a 5 minute exposure, a Leonid streaked across the sky in the general area where my camera was pointed. perhaps i caught one on film, but I need to develop it first.

On a side note, what is the best way to develop this film (200 ISO 35mm)?
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Old 21-November-2006, 07:48 AM
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Default Developing film

Hi Gob332 - since I've used digital exclusively for the last 4.5 years, the only recommendations I could suggest would be what I've heard and read from others who have used film for astrophotography. The suggestions I've seen are these: First of all, be sure you are using a good, reliable print/slide laboratory - not a one-hour corner drugstore type of place. Many years ago, I had taken a bunch of vacation pictures (35mm print film) in to be developed by one of these, and their chemicals were way off or out of calibration. All of my prints turned out with a horrible greenish cast (another good reason I'm glad I switched to digital). I don't know if you've used this particular film before for night photography, but some films suffer from what is called reciprocity failure. Others may show odd color casts; at least the film I had used years ago gave me some problems. Secondly, it is a good idea to take at least one or two "daylight" images - normal scenes taken of your car, boat, girlfriend, etc. during the daytime. This will give the film technician at least what he considers a "normal" image to process and a way to "register" where one image starts and stops on a strip of film. If you don't have some type of daylight-exposed image for him to go by, there could be a good chance you may get you negatives back with a comment like, "Sorry, nothing's on these - better luck next time!" And finally, one of the best things I've heard is to be sure to tell the film technician NOT to cut the negatives. If he can't find an accurate start or end of an image, they may cut the negatives - right through the only good shot you took of your favorite nebula. There are probably a bunch of other good suggestions, and I'm sure there are some film-experienced astrophotographers in this forum who could give you some good advice.

Hope this helps. Thanks for your comments and your question.
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Old 21-November-2006, 10:16 PM
Gob332 Gob332 is offline
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Quote:
Originally Posted by AutoClub View Post
Hi Gob332 - since I've used digital exclusively for the last 4.5 years, the only recommendations I could suggest would be what I've heard and read from others who have used film for astrophotography. The suggestions I've seen are these: First of all, be sure you are using a good, reliable print/slide laboratory - not a one-hour corner drugstore type of place. Many years ago, I had taken a bunch of vacation pictures (35mm print film) in to be developed by one of these, and their chemicals were way off or out of calibration. All of my prints turned out with a horrible greenish cast (another good reason I'm glad I switched to digital). I don't know if you've used this particular film before for night photography, but some films suffer from what is called reciprocity failure. Others may show odd color casts; at least the film I had used years ago gave me some problems. Secondly, it is a good idea to take at least one or two "daylight" images - normal scenes taken of your car, boat, girlfriend, etc. during the daytime. This will give the film technician at least what he considers a "normal" image to process and a way to "register" where one image starts and stops on a strip of film. If you don't have some type of daylight-exposed image for him to go by, there could be a good chance you may get you negatives back with a comment like, "Sorry, nothing's on these - better luck next time!" And finally, one of the best things I've heard is to be sure to tell the film technician NOT to cut the negatives. If he can't find an accurate start or end of an image, they may cut the negatives - right through the only good shot you took of your favorite nebula. There are probably a bunch of other good suggestions, and I'm sure there are some film-experienced astrophotographers in this forum who could give you some good advice.

Hope this helps. Thanks for your comments and your question.
Thanks for the help. I am extremely new at this and am just starting out. In fact, this was just my second trip out attempting night sky photography. I live far north of any major city which allows for extremely dark nights and clear skies so I am very excited at the prospects for good photographs. I have been considering purchasing a digital camera because of the benefits that are associated with it but since I am in college right now the funds aren't exactly secured.

Again, your help is greatly appreciated.
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Old 22-November-2006, 07:16 AM
mickal555 mickal555 is offline
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Wow! Cool amazing!

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Old 22-November-2006, 11:58 PM
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Meteor or no meteor, it's still a very striking shot. Well done.
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Old 23-November-2006, 12:29 AM
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Very nicely done!
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