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pagnamenta
07-29-2006, 12:24 PM
My grandpa is coming home from Germany Wednesday and he wanted to shoot some photos of stars. He was a physics professor at UIC and he's very much into astronomy. Do you have any tips for me.

He knows the basics, like aperature and shutter speed. I know more than him, but I would just appreciate a few tips so that we aren't out all night figuring it out.

I've shot a few shots handheld just to see what settings I need to use to make the stars visible. I shot at ISO 100, f4, at 30 seconds and I got the stars to show. That was my first shot, it came out good. I'm guessing I'll need to shoot for 3-5 hours to get good star trails using a tripod.

toriaj
07-30-2006, 10:59 AM
What camera and lens are you going to use?

pagnamenta
07-30-2006, 12:45 PM
Canon Digital Rebel and 75-300 f4-5.6.

Norm in Fujino
07-31-2006, 04:56 AM
My grandpa is coming home from Germany Wednesday and he wanted to shoot some photos of stars. He was a physics professor at UIC and he's very much into astrology.

I hope you meant astronomy or I worry for UIC's physics program.:p

pagnamenta
07-31-2006, 06:44 AM
I see I mixed those up. Luckily for me, I don't plan on going to UIC.

toriaj
07-31-2006, 08:16 PM
I'm interested in trying star photography, too. I did a Google search on Star Trail Photography. This is what I learned:

1. The narrower your lens, the more of the sky you will get into your frame. When I try, I'll probably use my short end, maybe 18 - 25 mm range. Use a relatively wide aperture, although stopping down 1 or 2 stops can help to have a sharper photo.

2. Take the shots during the new or crescent moon. Choose a very dark location! Watch out for dew and fog. There are techniques on the sites for reducing it. Of course, you need a cloudless night.

3. If you want the "circle" look, point the camera north. Have the battery fully charged. Begin two hours after sunset. End it two hours before sunrise. If you point the camera due east or west, you get stars circling in opposite directions. Shorter exposures give you streaks rather than circles.

4. Hat trick - use a card, or your hat, or your hand, in front of the lens when you open and close the shutter. That way, if you knock the camera a little, your "hat trick" will be blocking the sky and you won't get messed up star images in your photos.

5. Stabilize the tripod. Remember you're fighting against wind for a long exposure!

In this thread, Prospero describes how he got a 20-second exposure by using elastic to hold down the shutter button: http://www.dcresource.com/forums/showthread.php?p=132330&highlight=elastic#post132330

Post your results! Tonight is too cloudy, but I'll be trying some shots soon! I think I'll start out with 5-minute shots or so, then try going longer.

marcin
08-07-2006, 06:00 PM
or instead of the hat trick, simply put it on timer (auto pic taking) and sit back... 2/10 seconds later the exposure will start. thats what i do for night shots.

Unholymoondog
09-06-2006, 09:18 AM
I took this one last night of the constellation of Cassiopeia. All the shooting info is in the exif data. I have only had my D50 for a couple of days and I was just experimenting. I was impressed by the lack of noise even at iso 1600. I drew the constellation line in to aid perception.

I used a technique in photoshop to really bring out the low magnitude stars after the initial raw processing using Nikon Capture.

I have a long way to go but I love the D50 and I can't wait for further results, I know I can get better results.

Anyone else got some star pics to show ? There must be loads out there :)

http://img485.imageshack.us/img485/968/cassiopeiayz4.jpg

toriaj
09-06-2006, 02:53 PM
Beautiful shot! It might help if you didn't quite connect the dots. Leave a little space around the star so that we can see it better. But I am inspired to go try it myself, now!

Unholymoondog
09-07-2006, 03:20 AM
Great go and give it a go :D It's good fun experimenting. I have still got a way to go to get the results I want, but I am enjoying the testing.

I just put the Constellation line in to help orientation. I will leave them out if I post any further images.

I'm looking forward to seeing other peoples results.:)

toriaj
09-07-2006, 07:00 PM
I like the lines showing the constellation! I just mean, take the line close to the star, but not quite. Leave 1/16" or so blank around the star, so that we have a clear view of the star, but we still get to see the stars connected in the constellation. (IMHO) I'm excited to see more!

toriaj
09-25-2006, 12:36 AM
I finally tried my hand at this type of photo. I need to learn some more -- I kept getting an error, "Job NR." But if I turned the camera off, then back on, I had the photo after all.

My Sigma 70-300 got sharper stars than the 18-55. But the smaller field of view didn't work to get full constellations. I think it was a focus issue on the 18-55, but it was hard to see the stars to get correct focus. There's no PP on any of the shots except for noise reduction.

I got a familiar constellation with the 18-55:
15702

Here, a 30-second exposure with the 70-300 yielded short trails. You can see how bright the stars were tonight! It was beautiful.
15701

And a southern constellation with the 70-300. I don't know what it is yet.
15703
Any comments or suggestions?

toriaj
09-25-2006, 01:06 AM
**I learned that the southern constellation is Cetus. :D

Unholymoondog
09-28-2006, 07:38 AM
Hey Great shots :D

I gotta get out soon to do some more.

toriaj
09-29-2006, 09:13 PM
Thanks! How did you focus in your shots?
Soon I'm going to try the moon ... :)

Unholymoondog
09-30-2006, 04:55 AM
There is probably a better way!! but I focused on a house with lights on far on the horizon, set the AF/MF switch to manual and off I went. It worked out pretty well. I have a FZ20 as well and when I use that I just leave the lens cap on press the shutter button half way it's resting place at the end of trying to focus is infinity, I then just use the switch to go to MF again. I have not tried the D50 yet to see where the focus rests with the lens cap on, hence I used the horizon method.

I enjoy shooting the Moon, but for me the Stars are where my passion lies.

Well done again they are really good:D I will hopefully get out again in the next couple of weeks, but the forecast isn't great for the next few days.

Prospero
09-30-2006, 05:29 AM
I finally tried my hand at this type of photo. I need to learn some more -- I kept getting an error, "Job NR." But if I turned the camera off, then back on, I had the photo after all.

My Sigma 70-300 got sharper stars than the 18-55. But the smaller field of view didn't work to get full constellations. I think it was a focus issue on the 18-55, but it was hard to see the stars to get correct focus. There's no PP on any of the shots except for noise reduction.


Great results, Tori. There's amazing amount of stars in your picture. Here in the Netherlands I never can get quite as much stars to show up in my pictures due to light pollution of the cities, the highways or the greenhouses. I'll definitly give it a try again when I am in a more rural region.

If you want to take such pictures with the 18-55 you should use manual focus and focus on infinity. This may be difficult since the 18-55 does not indicate what distance it's focussed on (unlike your 70-300). Focussing on the horizon as described by Moondog may also work. The 18-55 does not auto focus correctly on the stars because these objects are too small and the contrast between the stars and sky is too dim.

The Job NR is not an error, it indicates that the long exposure noise reduction is at work. The Long Exposure Noise Reduction system works by taking another picture after the exposure is finished without opening the shutter. The noise which is then recorded is subtracted from the exposure. This process takes roughly the same time as your exposure.

toriaj
09-30-2006, 09:05 AM
Thanks for your comments, unholymoondog and Prospero. The horizon method might work, although there's not much out there to focus on (hence the beautiful stars!) This was only 5 minutes away from my house. I drove up the canyon a little way to a reservoir. I had cars driving by maybe 3 times in 1 1/2 hours, but that was it! :D

After I posted about the Job NR "error," I looked it up and found out that it was just the NR in process. But I did not know that it takes as long as the original exposure! Thanks a lot. Normally, I wouldn't wait around that long!!

I've heard about infinity focus before, but I don't really understand it. Does it mean the focus all the way at the end of the range? You just turn it as far as it goes and leave it there?

Prospero
09-30-2006, 02:42 PM
I've heard about infinity focus before, but I don't really understand it. Does it mean the focus all the way at the end of the range? You just turn it as far as it goes and leave it there?

Well, it is slightly more complicated than that. Focussing on infinity means that you focus on something which is 'infinitly' far away. How far away that really is depends on the focal length of the lens. At 18mm you will reach infinity sooner than at 300mm.

However, for some reason, many lenses can focus beyond infinity. Therefore, if you turn the focus ring all the way the result may become blurry, because the lens will be focused on a object farther away than infinity (At physics courses I learned that the object that the camera is focused on would virtually be behind the camera)

On your 70-300 you can easily see if it is focussed on infinity. The lens is focussed on infinity if the line on top of the lens is at this symbol: 8 (but then on the side). Note that the lens does turn a little further than that.

I can think of only one way of finding the point where the 18-55 focusses on infinity. It can be done by focusing the lens during the day on the horizon and marking the point on the focus ring which is on top at that time.

toriaj
09-30-2006, 04:48 PM
Ok, I'll give that a try! Thanks!

Dread Pirate Roberts
09-03-2008, 03:56 AM
Lenses turn a bit beyond infinity to make sure you can get infinity despite manufacturing tolerance, thermal expansion, atmospheric pressure and temperature and anything else that may affect focus.

Good link back to an old thread Tori, I'm inspired to give it a go. Wish we had a pole star in the southern hemisphere, I'll try the tip about just pointing North.

The moon was mentioned in this thread. In this sites picture galleries there is a perpetual moon thread. It has nice examples and points out the moon is a bright object and needs fast shutter speeds. It's so bright you can almost photograph it handheld.

@dam
09-08-2008, 06:29 AM
If you can get the milky way in, astrophotography without streaks can be nice. I took this at 10mm, 90 sec, f3.5, iso1600 in New Zealand (see the clouds of Magellan). In hindsight, I should've stopped down a bit more and done maybe 70 sec exposure. If you look at the original there is a bit of noise.

http://farm4.static.flickr.com/3002/2399151331_aa4a4ec116.jpg?v=0

toriaj
09-08-2008, 03:30 PM
That's gorgeous, @dam. What a view!

@dam
09-08-2008, 10:24 PM
Thanks. That was my very first night ever taking star pics. I just guessed at all the settings for a few shots until I came up with that. I think stopping down would've increased sharpness a bit, and if you look at it full size you can see the stars are beginning to streak, which is why a slightly shorter exposure would've been preferable.

I took that pic in April on an around the world trip. The rest of the pics are at flickr.com/adamandshawn, or you can see them with stories on my blog at www.adamandshawn.com

TheWengler
09-08-2008, 10:53 PM
I agree, that's a wonderful shot. I'll have to try that.

accord2003
09-10-2008, 08:55 PM
@dam.

that is an amazing shot.

I thought I give it a go. It seems there are still too much light pollution. I have go further into no where land. Anyhow, it was fun trying.

http://farm4.static.flickr.com/3045/2847703636_7a95b5e35b_b.jpg