Dark Filters

[Photos001]

I'm relatively new to photography, 12 months. I want to play around with using dark filters for long exposures and was thinking of getting these - http://www.amazon.co.uk/DIGIFLEX-72mm-Neutral-Density-Filter/dp/B0042RIJ3W/.

They seem pretty good value for money but am wondering whether to get 1 good quality filter such as this (http://www.amazon.co.uk/Hoya-72mm-NDX8-Screw--Filter/dp/B0000AIS27)

Any advice?

 

[arclight]

Don't expect much for £12.99 .................. that is in the rubbish league.

 

[damianmkv]

How long an exposure do you want ? Ie what do you want to achieve ? An nd8 would be ok but I wouldn't bother with the other 2.

For example if your shot was at 1/250s, this would become 1/125 with an nd2, 1/60s with an nd4 or 1/30s with an nd8

If you want smooth water shots for example, you need something stronger

 

[Photos001]

damianmkv, thanks for the breakdown - wouldn't it become 1/60s with an nd2? Otherwise the nd2 would do nothing?

Half the problem is I'm not sure what I want, which is why I was veering towards the 3 set filters. I'm planning to do sea/waterfall shots at dusk so though nd8 would suffice?

 

[damianmkv]

Sorry, should've been 1/250s to start with ( distracted by my moaning kids. Edited now )

 

[markmullen]

It depends on what you want to achieve and what light levels you're working in.

Have a look at my blog on long exposures, http://www.markmullenphotography.co.uk/blog/2012/8/long-exposure-photography---my-tips

 

[Nod]

Depending on the amount of milkiness you're after, you might even get away with just low ISO and a polariser at dusk at this time of year, especially with waterfalls.

 

[HoppyUK]

ND filters can be marked in different ways according to how dark they are.

One stop = x2 or 0.3; two stops = x4 or 0.6; three stops = x8 or 0.9; four stops = x16 or 1.2; and so on.

For milky seas and streaky clouds, most people would go for at least six stops, maybe ten stops of density, though you need a lot less ND if it's not too bright, eg early/late in the day. Note that ND8 is only three stops. Ten stops is ND x1024 (usually rounded to x1000) or 3.0.