How to get "dark sky" photography effect

[glypo]

Something I've always wondered about and wanted to try myself. I've noticed a few people on here with photos like this:

http://fc02.deviantart.com/fs26/f/20..._by_mole2k.jpg

http://i197.photobucket.com/albums/a...poncy/lcr2.jpg

(Just picking two of the first examples I found).

I think I am correct in saying you can get the effect using a gradient filter, perhaps grey? But is it better to shoot normally, rather then filter, and apply the effect in post-processing? If so hows the best way to go about it in photoshop?

Thank you so much

[Cruise]

A polarization filter will do the trick.
Check here :http://en.wikipedia.org/wiki/Filter_...y%29#Polarizer


Cruise.

[CAClark]

I always do the effect post in photoshop. OPen your shot, then add a 'Selective Colour' adjustment layer. Then in the drop downs select first Cyans, and up the black slider to 100%, then select Blues, and adjust the back to 100%.

You should find blue skys have dipped to a dramatic dark blue. You can adjust the opacity of the selective colour adjustment layer to tweak how much of the effect there is.

If you then Alt+click on the mask icon on the adjustment layer (the plain white oblong), the screen goes white. You can then add a black to white gradient in there. When you click back to the main image layer, the gradient will ramp up the effect from one and of the gradient to the other (depending which way and what angle you added the gradient fill).

Cheers!

[P_B]

I carry a 4-stop ND grad and quite often use that with my kit lens to get the effect right off the bat, however it isn't big enough to properly cover the Sigma 10-20 at the wide end (as used in that shot) so those get a gradient layer blended in 'soft light' mode and then a bit of poncing around with layer masks.

As CAClark says, a polarising filter used correcly on a wide angle can give that effect straight out of the camera too. Never tried it his way in Photoshop though, will give that a whirl

[mole2k]

A graduating ND filter will do this, as will a polariser in certain conditions. I use gradients in photoshop a lot of the time.

New layer in overlay mode, then just have a black to clear gradient and drag it down, adjust opacity to change the effect strength.

[glypo]

Wow, this place makes dedicated photography forums redundant for me.

Thank you so much for the help, I will try all of the methods and see what I get on with. You guys rock