This is a discussion on Star Trails within the Night Photography forums, part of the PHOTO GALLERIES category; My first attempt at shooting star trails failed. For whatever reason, the camera stopped shooting after fifteen frames. Checking the camera, later, it worked fine ...
My first attempt at shooting star trails failed. For whatever reason, the camera stopped shooting after fifteen frames. Checking the camera, later, it worked fine for many more shots. Of course it was too late then to attempt another batch of photos because it was now 4.30 a.m. and dawn was approaching. Still, I'm happy with what I did get.
I did some reading up on how to shoot star trails, and there seems to be a consensus that shots need to be 30 seconds long, with an ISO of 800. My aperture was f/6.7. I found this was much too long, and a lower ISO would have been better. I ended up with fifteen ten-second exposures at f/6.7, ISO 800. The result is seen below.
Does anyone here have experience with shooting star trails, and what advice would you give, please? Your photos are welcome on this thread.
06-10-2012 06:23 AM
Haven't done star-trails, John, but I have monkeyed with night shots before. Firstly, 30 seconds must be a minimum length of time, because the apparent motion, is after all, fairly slow :
approx. 1 degree of arc per 4 minutes clock-time, so in that time, the apparent motion is only approximately 0.125 of a degree.
An ISO of 800 is way too high, methinks. Firstly, you don't want fast film, because it will overexpose too quickly, and secondly because it reduces the image-quality.
Bear in mind, though, that long exposures will almost always blur movable things like flags, vegetation, water, etc, so bear that in mind when composing.
Suspend a big, ******' heavy brick from your tripod, but wait for the weight ! (Ie, wait for it to stop swinging before opening the shutter !)
I would use ISO 100 at the very most, and my smallest, or next smallest aperture - you want sharpness, but not vignetting, so consider composition
carefully, because you may end up with some vignetting which you might wanna crop.
Exposure times ? At least 5 minutes, I would think, to give yer stellar objects time to move a little. 5min clock-time = approx 1 degree and 15 minutes of arc.
That's not much, but it's 10 x the trail that 30 seconds would give.
(I am also hoping that Sparky casts an eye over this in case there are any mistakes, hehehe,
cos Sparky knows waaay more about this than I will ever do.
His astronomical knowledge is significantly impressive.)
Anyway, I would probably wanna get my "money's worth" and go for 10 - 20 minute exposures, maybe even 30 minutes.
(Longer is possible - it just depends on the effect that you want - longer times mean longer arcs of light, obviously.)
Last edited by bert; 06-10-2012 at 04:31 PM.
The 10 second shots with a 1 second interval definitely shows movement of the stars, but I'm inclined to agree on 30 second exposures. When I first started the camera recording, I stopped it after two shots because I didn't have the timing set right. I got two 30 second frames and they were much too light. Obviously that ISO 800 is too high, so I agree with the 100 ISO, too. The f/6.7 is probably too wide, too, but these were the recommended settings that several websites gave. I need to experiment.
It was a still night so the trees were not being blown around. I know long exposures would make for blurred trees. It was a perfect night for this project but I just messed it up. If I didn't have to go to work tomorrow, I'd go out there again tonight, but a bit earlier.
A man in Australia said he accidentally left his camera open for a couple of hours with just one exposure, and said that it could have burned out his sensor, but it gave him a great photo with star trails.
Now that I know how to work the Intervals timer on my camera, I had another go at star trails last night. I'm not happy with the color but looking through the individual frames, I see some where car headlights apparently lit up the sky and trees, giving the finished picture a ghastly brownish/amber glow. Ninety frames were shot with 30-second exposures, but a previous attempt with shorter exposures gave me a blue sky. (See initial photo at start of thread.)
So I colored it to make it look better. I hope somebody will help me out, here. My wife says it looks purple. I thought it was blue. I'll go with what others say it is.
Last edited by John B.; 06-20-2012 at 07:44 AM.
you should change the white balance for a cooler (2900K is fine).
If you shoot in RAW, you can fix it easily.
Regarding the photo, the color is blue, but blue trees are unreal...
Will changing the white balance prevent that brown sky?
Originally Posted by BonoVox
Shooting in RAW. I've read that I shouldn't do that. Would I have to convert the files to JPGs before stacking them? That would take hours.
The trees in the blue picture look unreal but I only tinted the whole photo to see what a blue sky would look like. I want to achieve the natural look I've seen in other photos.
I appreciate your advice. Thanks.
Last edited by John B.; 06-23-2012 at 10:56 PM.
Yes, the white balance prevents (no miracles) the orange / brown in the sky. You can try, but with 2700k or 2800K is enough.
Personally, when I do a startrail or other photos, always shot in RAW. It is much easier to make edits.
If you are using photoshop (cs5 is mine) you can select all RAW files and drag them into Photoshop. That way, you can edit them all at once. After only saves in TIFF or JPEG and use the "startrails". (I recommend work with TIFF but a high quality JPG is fine.)
Thank you, BonoVox. I will do those things. I edit with Corel Paintshop Pro but it will edit batch files in RAW. As soon as the stars show up again, I'll give it a try. Right now we have had days and nights of high humidity and cloud, and are just coming out of a tornado which hit us this morning. No power for twelve hours. I'll post again as soon as I have something.