The polarizer, and graduated neutral density filters (grad. NDs) are the only filters you really need with digital, since post processing can duplicate the effects of most other filters.

I suppose you could use a red filter with your camera in b+w mode if you wanted to do more in camera for black and whites, but it's not hard to convert later, and most people would rather have the option of color or black and white.

9-stop neutral density filters are all the rage on NSoP right now, since they allow you to have long shutter speeds even during midday sun, so that you can have movement in your photos without having to use really small apertures, really low ISOs, or waiting until there is less light.

Very cool! Thanks for the reply. I'll have to pick one up..

How about the UV? What's it used for?

How do I keep my polarizer from darkening up the sky so much? It's not on all days. Most days it's incredible, but I noticed when I was shooting in Seattle this winter, on a bright blue clear day, the sky was DAAARK.

The UV filter is nothing more than a protector for your lens. It's a big debate and seems like every other person is on the opposite side. Honestly, I don't use them and never will. I think they're a waste.

As for the polarizer, it's all about your angle to the sun and how wide your lens is. But, the reason you're describing is why I rarely use a polarizer for the sky. I mostly only you use them to control reflections/glare when shooting water.

Originally Posted by Gregger

Very cool! Thanks for the reply. I'll have to pick one up..

How about the UV? What's it used for?

Most people use a UV filter to "protect" the front element of the lens--i.e., when it's dirty and needs to be cleaned, you risk scratching a $20 filter, not a $500+ lens. Any glass added between the image and the sensor can potentially cause loss of IQ due to flare, ghosting, etc. It's a tradeoff.

How do I keep my polarizer from darkening up the sky so much? It's not on all days. Most days it's incredible, but I noticed when I was shooting in Seattle this winter, on a bright blue clear day, the sky was DAAARK.

A lot of people like that darkened effect. That said, the polarizer polarizes most perpendicular to the sun--so it will be darkest when the sun is on your right or left, and lightest when the sun is behind you. Also, you can rotate the polarizer to affect how much it is polarizing. If you really want a light sky, just remove the filter!

Thanks guys. I'm still learning, and while I've learned a lot, I have a long way to go.

Ok, I figure I'd post this here instead of starting a new thread. I am looking for a circular polarizer for a sigma 10-20 and came across the Hoya pro1 digital.

http://www.bhphotovideo.com/c/produc...izing_Pro.html

$194 on BH but only $68 on ebay

http://cgi.ebay.com/HOYA-77mm-PRO1-D...QQcmdZViewItem

what's the deal? is there something that I am not seeing?

I don't know what the deal is there, but you should be able to get a good, Hoya multi-coated polarizer that is 77mm (size of threads for 10-20) for ~$80. They have several different flavors, but the $70-$80 work pretty good.

Originally Posted by Markitos

I don't know what the deal is there, but you should be able to get a good, Hoya multi-coated polarizer that is 77mm (size of threads for 10-20) for ~$80. They have several different flavors, but the $70-$80 work pretty good.

I was just looking at Hoya 58mm PLCirs on Amazon.

The multi coated HMC is only $45: http://www.amazon.com/Hoya-HMC-Filte...9647113&sr=8-5

Do I really need the Pro version for $75? http://www.amazon.com/Hoya-Digital-M...647253&sr=8-20

I know cheap filters over good glass = bad, but I wonder what makes the Pro so much better.

Originally Posted by PhatheadWRX

I know cheap filters over good glass = bad, but I wonder what makes the Pro so much better.

The PRO filter is thinner than the regular one so that it doesn't vignette on ultra wide angle lenses. If you don't plan to use UWA lenses, I'd get the cheaper one. Even if you DO use UWA lenses, I'd test the cheaper one, see if it vignettes on your lens, then go from there.

As mentioned in this thread, on the Sigma 10-20mm, my plain jane Hoya HMC CP doesn't vignette at any focal length, so I didn't need a thinner one.

Thanks! I'm looking at a 58mm for the kit lens and 70-300, so I doubt I would have a vignette problem. Will test.

a lot of the "good" filters ,especially the UV ones, are truely a clear element where as the "cheaper" ones have a "tint" to them...just lay a B+W and a Promaster on a piece of white paper and see what I mean.