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Had a chance to spend a weekend away, so I had my first attempt at some night sky star shots... Unfortunately it was also a full moon night, so the sky was a lot brighter than I had expected... takes away a bit of the contrast with the stars.





I'd appreciate any feedback you have, thanks

Hey Nikko,

I like #1 more than #2 as it has better composition. Maybe you can improve by cropping to square to include the lit tree as the main element with the starts complementing it a bit.

Where abouts was this? You will need extremely dark moonless clear (no dust or haze) nights to get star trails (if that's what you wanted). Usually need to be very isolated to get rid of the city lights contaminating the sky.

I don't think a full moon will affect the exposure for the sky. This could only be if there's diffraction from moonlight in the atmosphere and especially if it's clear I doubt that would be significant.

Also, no, you can get full star trails at the full moon. I've taken exposures up to 8 hours on film on or near full moon. The full moon is useful so you can get the landscape in as well, a problem at the new moon with any camera.

Thanks Murray.

I have tried a few exposures in full moon and didn't work out. [I think I may have had some flare from the wideangle though! ] And it may have been slightly hazy...

Thanks for the feedback and suggestions...

I guess my reasoning for thinking the moon would affect the image is that the overall surroundings were quite bright as a result of the moon, so I figured the light would leak into the image too. I didn't really expect to get star trails, as my exposures were much too short (30 secs), I didn't really have the patience to go all night.

The location was out in Daylesford, where there was minimal lighting. The place I stayed in was about 10 mins drive away from the Daylesford town, very isolated and dark... dark except for moonlight that is.

Surenj

The easy way is to take a quick exposure or two at high ISO to get the correct exposure first (and you could check for flare). Not so easy in the old days with film when I was using Fujichrome 50, shooting with large format lenses that were f5.6 or f6.8 wide open and making large compensations for reciprocity. You had to get it right first time.

Nikko

You can even include the moon, which will probably appear as a wide streak, without affecting the exposure. ... And the exposure for taking a (telephoto) photograph of the moon itself is the same as full sunlight in the middle of the day. You don't need an 8 hour exposure for star trails. I remember getting quite good star trails with a 20 minute fisheye exposure.

Just wondering though, wouldn't having an even longer exposure time result in a brighter sky? It's already quite blue as it is.

A longer exposure time is not the same as more exposure. You may need to stop down or use a lower ISO to get the long exposure time.

Actually, I like the second as is. It has
more visual elements, as you would
expect walking in the moonlight in any
rural area.

Murray Foote wrote:A longer exposure time is not the same as more exposure. You may need to stop down or use a lower ISO to get the long exposure time.

Oh, that's obvious enough... haha, me being stupid.

I was wondering how to get better contrast between the stars and the sky though (ie, darker sky, brighter stars)... does the longer exposure time make the stars appear brighter (answering my own question)?

No, assuming you have the same overall exposure because the same amount of light is hitting the sensor. The effect is also different if you have a wide angle lens, especially an ultrawide.

Optimum exposure for the star trails is an interesting question, though (as distinct from optimum duration of exposure to maximise or minimise star trails). There could be a case for testing different overall exposures, with and without star trails, even at the new moon, and then for the actual exposure, combining an exposure for the sky with an exposure for the landscape. Never heard of anyone doing that, though.