Filters....

[Sair33]

I'd like to buy a few filters for my Canon 300D, UV, Polarising and a few graduated filters maybe... can anyone recommend which 3 or 4 would be best to get, and where is best to buy from?
I've looked on Ebay but its impossible to tell whether the ones from HongKong etc will be decent quality!

Thanks

[brammers]

UV/skylight/clear filters protect your lens. Use these if you've got something valuable or if you're going somewhere likely to mess your lens up. Be aware that by the time you spend enough to get a UV that doesn't degrade IQ too much you may well be approaching 1/3 of the cost of cheaper lenses - up to you if it's worth it. FWIW I have them on my Zeiss lenses, but leave them off my 2 150quid lenses.

CPL filters cut out polarised reflections - including pretty much everything that's reflecting off water. This includes anything with water in it - plants, the sky, eyes, even faces to some extent. Everything that has the reflection cut out of it becomes more saturated - it looses the glare. Think bluer skies, greener plants, clearer waters.

ND filters simply suck up light. They make AF harder and mean that you have to use a longer shutter speed. Use these for car trails, star trails, waterfalls, fireworks... anything whose movement you want to exaggerate. Use enough and things become ghostly. Tbh go for extremes with these - in the day you're unlikely to see much difference with an ND8 - stack ND 10s for real effects.

You might also get use out of grad NDs. These are more subtle - they're designed to equalise the dynamic range across a scene so that you don't get say a beautiful sky with a black forground. In reality HDR techniques might be a better bet.

If you want to get REALLY tecchy then look into which channels you clip on a regular basis and buy colour filters to equalise the light exposure across all channels. Each camera has a different profile but you'll generally find that magenta filters do the job. You'll get better exposures and less shadow noise. Strictly for sensor geeks and landscapers though.

7dayshop is a pretty decent place for filters

[Alex]

TBH, the only filter I find of any real use is a circular polariser.

I'd much rather protect my lenses with a hood than a UV filter as this has a postive effect on pictures.

The effect of an ND grad can be done much more cleanly in photoshop/the GIMP, especially when shooting in RAW. A non-graduated filter is of limited use - only really when you want a slower shutter speed than the light will allow - for waterfalls for example. I doubt you'd use them that honest to be honest.

An IR filter can be fun, but is a bit niche.

Decent quality filters cost quite a bit too - especially if you have large filter sizes. I have a 67mm and a 77mm circular polariser and together they cost me £100, and that was with a discount.

[brammers]

http://www.flickr.com/groups/nd110-filter-group/pool/

That's what an ND filter can do. The streaky clouds and ghostly waters in daylight aren't available any other way. Can be fun.

I'm undecided about the effects of UV filters on characteristics like lens sharpness. One area they definately have an effect though is ghosting and flare - you'll often find bright lights get repeated as 'ghosts' on your shots and flare is easier to provoke using anything but the most expensive multi-coated UVs.

Forgot about IRs - also fun.

[Alex]

I just think ND grads are quite a lot of cost and hassle for what you can do just as effectively from RAW shots by using different exposures for sky and foreground. Here's one I took the other day which shows two shots (one for sky and one for foreground), both from the same RAW, combined with the GIMP to give the same exposure difference as an ND grad would have done:



The other advantage is that an ND grad has preset stops of exposure, is hard or soft edged, and can only realy work well for straight lines. Doing it in photoshop allows you to have a relatively hard edge to your graduation over, for example, mountains. This is less important in the photo above, but can be annoying if you have one big mountain, which would appear dark or the sky next to it looking too bright.

[Bobster]

alex you're mixing up an NGrad with an ND, 2 totally different tools

the grad lets you underexpose an area

the ND lets u underexpose a whole scene allowing for very long exposures in daylight

[kalniel]

Originally Posted by Alex

I just think ND grads are quite a lot of cost and hassle for what you can do just as effectively from RAW shots by using different exposures for sky and foreground. Here's one I took the other day which shows two shots (one for sky and one for foreground), both from the same RAW, combined with the GIMP to give the same exposure difference as an ND grad would have done:

Except you're losing information - there's only so much headroom in RAW so if you need to change the exposure by more than a stop you're quite likely to degrade quality - and it only works if your camera is capable of recording the full dynamic range of a scene. Using 8bit the GIMP wouldn't help things either.

Where the scene has a very large dynamic range it's better to either take two or more shots in the first place to get the full dynamic range for blending later, or use an NDGrad so that all the scene falls within your sensor capacity.

Or use a good camera's dynamic range optimiser type setting - which will selectively apply a digital ND (lower ISO) to parts of the image and boost the ISO in others, so ensure the scene is fully captured. Fanastic stuff

[brammers]

Alex is right in a way - a lot of good stuff can be done when making full use of the large dynamic range in a RAW file.

But there's a lot of pro landscape photographers who use grad NDs. If you're really into your landscapes there's still a lot to be said for a very good filter system.

Kalniel - that's not how a camera's DRO setting works. They simply apply curves to a standard image - rather than clip JPGs agressively for punchy results they simply raise the black level and allow more highlight detail to come through. AFAIK there's no sensor on the market that can work at different ISOs on the same shot - definately not in consumer SLRs anyway. This is why DROs do absolutely nothing in RAW.

[kalniel]

Originally Posted by brammers

Kalniel - that's not how a camera's DRO setting works. They simply apply curves to a standard image - rather than clip JPGs agressively for punchy results they simply raise the black level and allow more highlight detail to come through. AFAIK there's no sensor on the market that can work at different ISOs on the same shot - definately not in consumer SLRs anyway. This is why DROs do absolutely nothing in RAW.

Ah, I understood them wrong then - I knew some just adjusted the black level, but thought others were more useful than that. Still a lot of room to improve then.

[shiato storm]

if you want a cheep but good get of ND grads the hi-tech filters from teamwork photo are perhaps some of the best available. fairly neutral colour so very little casting too...
or spend a load of money on some lee filters which are what the pros use, and yes they do make a difference, much much clearer qualitywise

[Zak33]

she wants a Polarizing filter.. because... I because I told her she wanted one

It's good for cars you see

so that one is my fault !

[Funkstar]

Sounds like your birthday present is sorted for this year Zak

[Whiternoise]

How much is worth spending?

I need to get a 77mm filter for my 28-70 and the prices range from £15 for a cheap Hoya to bordering on £150!

I was thinking go for the middle ground - http://www.amazon.co.uk/Hoya-77mm-Su...?tag=miro04-21 and one of these fellows http://www.amazon.co.uk/Hama-Circula..._ob_ce_title_1.

[Lowe]

Forgive my ignorance here, I'm looking from a different perspective in that my specialism is audio and I'm totally new to the whole photography scene.

Why filter at the source? Can it not be done in post production?

Now I can appreciate a UV filter to give you more 'headroom' in your shot so that's understandable. However gradients and the like? Is it not better to keep your source material as 'clean' and as 'standard' as possible (as we do it audio) then do everything in Post to get the shot that you want?

[kalniel]

Originally Posted by Lowe

Now I can appreciate a UV filter to give you more 'headroom' in your shot so that's understandable. However gradients and the like? Is it not better to keep your source material as 'clean' and as 'standard' as possible (as we do it audio) then do everything in Post to get the shot that you want?

Back to the correction of my assumption about ISO gain. If you can't adjust individual elements of the sensor then you have a fixed dynamic range - what do you do if your scene contains elements at both extremes? You can underexpose to get the bright elements in the range of the sensor, and overexpose (the scene as a whole) to get the darker elements, but not both at once. However, if you use a gradient filter then you are effectively underexposing some portion of the scene without underexposing the rest of it, allowing the full scene to fit within your sensors dynamic range.

An alternative is to take several photos at different exposures and blend them in post process, however only really works if your subject stays static. Taking photos from a plane or boat, or of something moving prevents 'HDR' methods from working well.

In audio you use a filter around the mic to prevent hard sounds from clipping and obscuring the information underneath that you're trying to record.

[Bobster]

Originally Posted by Whiternoise

How much is worth spending?

I need to get a 77mm filter for my 28-70 and the prices range from £15 for a cheap Hoya to bordering on £150!

I was thinking go for the middle ground - http://www.amazon.co.uk/Hoya-77mm-Su...?tag=miro04-21 and one of these fellows http://www.amazon.co.uk/Hama-Circula..._ob_ce_title_1.

remember if you put cheap optics in front of expensive ones, you may as well be using cheap all the way!