Star trails

[karenoliver]

I've been putting it off for weeks but I want to photograph some star trails over an abandoned psychiatric hospital. The building is listed and even though decaying is still stunning. The thing is I have no sort of starting exposure etc...

Do I expose for the sky and use a large torch on the building or use a very long exposure?
I have two of the those massive 1 million candle type torches for light painting the building. I did consider making seperate exposures, one of the building lit with the torch and one of the sky with stars streaking and blending them? I want the stars swirling around the building. There is not much light pollution as such, the area will be pretty dark.

What sort of aperture? I was thinking f11 and an ISO of 400 but am not sure. My worry is doing an hour long exposure and then finding it was underexposed and having to start all over again.

Karen

[karenoliver]

Just realised I posted this in the wrong thread. I meant to put it in photography technique, can someone switch it for me please?

Karen

[amk1977]

I found this was quite a useful link, Karen. It explains a few different techniques to achieve different looks, which I thought was quite novel.

[matt wilson]

Karen .My experience of this and from what I have read you may be better taking a series of shorter contimuous exposures and merging them .Otherwise noise becomes an issue .Lock shutter and set conintuous drive .Select exposure length and then just keep going .

I would think a few different shots of the building using torches would be the way to go .

Note if cold then batteries will take a hammering ensure fully charged or use a grip.

[Markulous]

I'd use the lens wide open - the building will still be in focus (oh, and don't use autofocus - set to infinity) and min ISO as you'll gain nothing but noise upping the ISO

Painting the building with your torches should work well - it's be worth establishing how long to leave the beam on each section (or how fast to move it) early on. Be worth using RAW to correct WB

[karenoliver]

Thanks everyone, great advice :-) I will be happy even if I just get the buildings lit up and no star trails. I just need to be brave now and go in at night. Its creepy enough in the daylight lol I'll probably stick to ISO 50 or 100 to combat noise.

Karen

[pburness]

Originally Posted by karenoliver

Thanks everyone, great advice :-) I will be happy even if I just get the buildings lit up and no star trails. I just need to be brave now and go in at night. Its creepy enough in the daylight lol I'll probably stick to ISO 50 or 100 to combat noise.

Karen

Hi Karen,
Here's another link for some good information / technique Star Trails

Phil

[karenoliver]

Thanks, Phil :-) I'll check it out in the morning. I did visit the hospital last night but the sky was cloudy so need to go back on a clearer night. I did use my bright torches to light the building but it was a bit annoying that both died after less than an hour!

Karen

[swan lover]

Wasn't this covered in a issue of Photo Plus not to long ago? looking foreward to seeing the results.