Long exposure on a Hasselblad 500 cm at night.

On monday morning there is suppose to happen a falling star event.
I am planning to shoot a long exposure around 30 min or so. I have a classic 80mm 2.8. Is better to use a negative or a dia film?I have a portra 160vc and Astia 100.
By the time I can't use any filter wich is the best combo suggestion?
thx

Yes, the Quadrantids are January 3-4.

Are you photographing from a dark location or a bright one? From the countryside or from the city?

Have you done night photography of the sky from there before? Do you know how long you can go before you hit "sky fog"? If you can, do some test shots tonight if you can get them developed tomorrow. Try 1 minute, 2 minute, 5 minute, 10 minute, 30 minute exposures to see where the fog will become a problem.

30 minutes is probably too long. I would try perhaps 10 minutes from the country or 5 minutes from the city. Take multiple exposures and perhaps close them early if you see a good meteor trail that you think went through your camera.

I used to prefer slides as I went to astronomy clubs and we projected the slides but practically either film should do well, just depends if you want slides or negatives.

Don't use a filter.

I just want to mention that you should not stop the lens down, so the star trails will be captured as bright as possible.

You'll get star trails, as you would on any clear night, but will meteors show up on the film? I'm not so sure...

Oh sorry, my English :-s I meant shooting stars ;-)
They will show up if they are bright enough. However, you will only be able to catch a small amount of the shooting stars on film that you actually see. I find Astia somehow suboptimal for this purpose. You should also consider Provia 400X, maybe even pushed to iso 800.

meteors

you will also need to work out the point in the sky the "shower" will originate from point the camera at this point it will help give you the best chance to record something most news papers have a short article on the night sky and will usually include a description of were to look and the time to look