Are filters necessary ?

[kry10]

I have just bought a Cokin filter system with a hard grad filter and it has got me thinking.
Apart from a UV filter to protect the lens itself, are filters necessary on a DSLr, seeing as we can
make any changes in post production with photoshop ?
Or, is it better to use a filter, then, make further improvements in post ?

 

[Buckster]

I have just bought a Cokin filter system with a hard grad filter and it has got me thinking.
Apart from a UV filter to protect the lens itself, are filters necessary on a DSLr, seeing as we can
make any changes in post production with photoshop ?
Or, is it better to use a filter, then, make further improvements in post ?

The only filters I find to be necessary these days are polarizers to cut through glare and reflections, and neutral density filters to achieve long shutters and still keep the aperture and ISO where I want them in brighter conditions.

All other filters, colored, special effects, even graduated NDs, can be dealt with in better ways digitally, from my point of view.

UV filters are trash as well these days. They don't do anything for digital shooters except lower image quality somewhat. And no, they don't protect your lens.

 

[WesternGuy]

My experience has been that, yes, you can "simulate" the effects of certain filters in post-processing, with the exception of a polarizer, which I have found somewhat difficult to reproduce in post-processing. Having said that, I still possess a reasonable complement of ND and grad filters that I find I prefer, rather than trying to duplicate the effect in software, particularly because I have also not had any luck in trying to reproduce the "silky" affect you get with water falls when I use a ND filter to increase my exposure. My 0.02¢ FWIW.
_________________
WesternGuy

 

[kry10]

UV filters are trash as well these days. They don't do anything for digital shooters except lower image quality somewhat. And no, they don't protect your lens.

I thought that a UV Filter would protect the front of the lens from scratches.

I have an ND8 filter and a polariser filter, what others would you recommend, if any ?

Also, would you suggest Cokin square type or the standard round type that screw to the end of a lens ?

 

[Buckster]

UV filters are trash as well these days. They don't do anything for digital shooters except lower image quality somewhat. And no, they don't protect your lens.

I thought that a UV Filter would protect the front of the lens from scratches.

Not in my experience. If you're doing things that might scratch the front element of your hundreds or thousands of dollars lenses, you've got other issues you need to work out. Lens caps and pouches and holsters keep them safe when they're not being used, and hoods and care keep them safe when you're looking through them and shooting photos.

In all honesty, I rarely ever even have lens caps on any of my lenses. I do use holsters and cases made to store them whenever I'm not actually shooting, for the most part, but when I want to shoot, I want that lens available RIGHT NOW, as soon as I pull it out, and I always have a camera ready at arm's length without a lens cap on - ALWAYS, even when I'm driving.

Other than the holsters and cases, I'm also not particularly careful with my gear either, tbh. They're tools to me, and when I'm using them, they are getting USED. I'm into making photos, not protecting an "investment". When that means getting down and dirtly, so be it. Not that I would point them into the wind during a sand storm, but I've spent a lot of time on beaches and deserts and every other kind of environment with them, and haven't had a problem yet.

And after all that, I still don't have scratches or gouges or problems with my lenses. First of all, they're tougher than a lot of people give them credit for. This glass ain't like the thin, easily breakable stuff in your windows (or in a UV filter). Second of all, minor scratches don't really mean much to image quality anyway, believe it or not. Check this out: Dirty lens article

On the other hand, I've used UV filters, starting about 40 years ago, when they were pretty much necessary for film shooting (where using them came from). They've always had a few problems associated with them when it comes to image quality, because they set up reflections and flare and other strange moire type image quality problems with the lenses they're on. Digital sensors have UV protection built right onto them, so you don't need it for that anymore, and the rest of the problems mentioned above go away when you remove that unnecessary filter.

The idea that they're useful to protect your lens is a marketing gimmick to try to sell you the filters when you buy your gear, because there's a huge markup on them and they're trying to sell you as much stuff as they can while you've got your wallet open to them. Lots of folks buying gear simply don't know any better, so it sounds good to them, and those additional relatively few dollars, compared to the several hundred or even thousands they're spending already, seems like a worthy drop in the bucket for the "protection" the sales team will tell you it provides. And though some people will hang on to that sales advice like it's gospel for the rest of their lives, ignoring the image quality issues of putting a cheap piece of glass in front of one they paid many hundreds or even thousands for and proclaiming they don't see any such IQ problems, it's just not true.

I have an ND8 filter and a polariser filter, what others would you recommend, if any ?

None, until you have an actual need for either more or less stops in an ND filter - then fulfill that need.

Also, would you suggest Cokin square type or the standard round type that screw to the end of a lens ?

I like and use both when it comes to polarizers. For Cokin, it's still a round polarizer, but fits into their square holder which makes it easy to place and remove, which is the beauty of the square systems like Cokin, Lee or others. For ND's all I've ever used are the square filters, and I like them just fine. Fair warning on the less expensive Cokin ND filters: They have a bit of a magenta cast to them, so you'll want to work out a way to deal with white balance on them. I use a collapsible gray card/target to deal with white balance issues.

 

[enzodm]

I have an ND8 filter and a polariser filter, what others would you recommend, if any ?

Both Buckster and WesternGuy told you that polariser and ND are the only ones that cannot be substituted by postprocessing, so no need for other filters. Except maybe graduate filters, when used to accomodate large light ranges (but typically you buy them when you know you need it, not under generic suggestion).

 

[Markw]

Agreed with everything said above. Buckster threw the book at you, and I agree with every word. Couldn't have said it better myself.

Mark

 

[Psytrox]

What are peoples experience when it comes to cheap polarised filters VS expencive polarised filters?

 

[Buckster]

What are peoples experience when it comes to cheap polarised filters VS expencive polarised filters?

Generally speaking, you get what you pay for. The difference in image quality can be pretty significant between the two. That's because the more expensive ones will usually use better glass, better coatings, more stringent manufacturing quality control, etc. Cheaper ones often introduce image quality problems from color casts to reflections and flares to moire patterns and Newton rings.

 

[Psytrox]

Thanks... I think I'll just leave it for now, and get a proper one at some stage later

 

[Tuffythepug]

It appears that Buckster has pretty well gone over the issue and I would agree with most of it. Sorry, but I still use UV filters on all my lenses and always have. I also wear seat belts but I don't really plan on having an accident cause I'm a safe driver. the point is, sometimes things can happen no matter how careful we are. And most of us who have invested quite a bit of money in a system of bodies and lenses take good care of them. But they UV filters don't do any harm and they could save your lens from a scratch that would be noticeable in a photo so I see no reason not to put one on. Perhaps I'm overly cautious

I do have quite a few cokin filters that I have left over from shooting a lot of B/W film years ago. I used the yellow and red filters a lot for b/w landscape shots primarily.

But I don't use any external filters when I'm shooting digital. (except the UV) As everyone has said, you can do it all in post processing

 

[enzodm]

But they UV filters don't do any harm and they could save your lens from a scratch that would be noticeable in a photo so I see no reason not to put one on. Perhaps I'm overly cautious

On this there is continous debate. Cheap UV filters indeed do harm to image quality (glares, abherrations,etc), and also are proven to possibly cause scratches in case of impact, because their thin glass, if broken even by something not particularly hard, may hit the lens coating. So, sometimes they may protect (mostly from finger grease, dust, water), but may also be a font of problems.

But I don't use any external filters when I'm shooting digital. (except the UV) As everyone has said, you can do it all in post processing

A couple of filters, as told in the rest of the thread, cannot be substituted by postprocessing: polarizer and ND for long exposures.

 

[Psytrox]

are proven to possibly cause scratches in case of impact, because their thin glass, if broken even by something not particularly hard, may hit the lens coating. So, sometimes they may protect (mostly from finger grease, dust, water), but may also be a font of problems.

If you get an expencive filter, will this still be a problem? Or is this only regarding cheap filters?

 

[Buckster]

But they UV filters don't do any harm

See the 4th post down on this page: 100-400 and a uv filter - Canon Digital Photography Forums

I've also actually tested my lenses with and without UV filters and found that they do indeed degrade image quality, which is why I ultimately stopped using them entirely.

and they could save your lens from a scratch that would be noticeable in a photo

I've yet to see anyone present actual evidence that this is true.

 

[john5189]

Had expensive filters on and I never got pin sharp images, thought it was just my technique/camera shake /ebay. This went on for years
Did the battery test/DOF test to see if the focusing point was off and in this safe non-abrasive environment bravely took the filter off to see what difference it made. WHAM. Everything sprang into life.

Use lens hoods to keep greasy fingers and sand paper away from the front element and be gentle with clean cloth when you clean it.