Newbie Question on Filters (ND and others)

[Mark L]

I currently have a UV filter on, mostly to protect the lens. Should I put a CPL on top of that or just use the CPL?

And it's debatable if a UV filter does much to protect the lens. Doesn't do anything for image quality really. Lens hood can give just as much protection in some cases.

[ameerat42]

I currently have a UV filter on, mostly to protect the lens. Should I put a CPL on top of that or just use the CPL?

Here you are in a position to actually try this for yourself. (I'm not saying one way or another.)

Pick a subject with some texture in it - a brick wall flat on, or something.

Take a number of shots: no filters at all; a UV filter; A CPL alone; a stacked UV and CPL.

Pixel peep the images, and make a set of 100% crop images to post here with your findings.

That will be empirical evidence rather than just relying on the experience of others.

---If you want to, that is.

Am.

[MadMax1412]

Take off the UV & just use the CPL. The UV offers no contribution to image quality.

I also use hoods as I assume these are to stop flaring on the lens from the sun striking at an angle. With a hood on, I find it hard to turn a CPL filter without my hand obscuring the view.

Are hoods all that good or should I ditch it.

[Mark L]

Are hoods all that good or should I ditch it.

It all depends on what you are trying to take a photo of, and how much time you have.
http://www.ausphotography.net.au/for...486-Lens-hoods suggests that if you can use a lens hood, good, but I'd think the times you need a CPL, it may be more important (but it all depends on what you are trying to take a photo of and how much time you have.)

[Steve Axford]

I think the best feature of a hood is that they protect the lens from both dust and more serious scratches. They are much better than a filter for this purpose. A hood on a wide angle lens has limited value as a dust protector, though they still serve some purpose in protecting your lens from accidental scrapes or falls. If you want to use a CPL, you should take off the hood as it does get in the way.

[MattNQ]

I also use hoods as I assume these are to stop flaring on the lens from the sun striking at an angle. With a hood on, I find it hard to turn a CPL filter without my hand obscuring the view.

Are hoods all that good or should I ditch it.

Hoods generally reduce flare & improve contrast. Up to you if you are finding it makes much difference or not in what you are shooting.
I find most hoods are not effective on my wide angles as the sun comes in from such a spot I need to use my hat at arms length to block the glare
A screw in rubber hood can work well with a CPL - you just turn the hood to turn the CPL (Just remember to turn it the right way & don't unscrew it )
I use a rubber hood on my 80-200. Gives a the pointy end bit of knock protection when its swinging around on a black rapid type strap

[Tin Whistle]

Hi All could someone please explain what CPL and ND means? I know they are filters but what sort?

[MadMax1412]

Is there any issue in using a CPL when taking indoor shots?

I have a large camera bag that I keep everything in when I am at home but when I go out, I usually just take a small bag big enough for the body and lens I think I'll be using for the occassion as I don't want to be carrying around too much all day.

[MattNQ]

Hi All could someone please explain what CPL and ND means? I know they are filters but what sort?

CPL - Circular Polariser. Wikipedia gives a reasonable explanation on how they work
http://en.wikipedia.org/wiki/Polariz..._(photography)


ND - Neutral Density - Effectively block a fixed amount of light. Usually used to allow a slower shutter speed for a given aperture & ISO to avoid overexposing. Handy for doing milky waterfalls in bright light etc. Also handy if you want a really shallow depth of field in bright light but your shutter is not fast enough (eg, my old EPL1 only had 1/2000 max shutter).

Again Wikipedia gives a fairly simple overview
http://en.wikipedia.org/wiki/Neutral_density

- - - Updated - - -

Is there any issue in using a CPL when taking indoor shots?

I.

Not really, but they will reduce your exposure by a stop or two, so you will have to adjust your settings to compensate.

[Tin Whistle]

Thanks Matt your explanation is much appreciated

[ricktas]

@Tin Whistle; this might assist too : http://www.ausphotography.net.au/for...Why-When-Which

[Tin Whistle]

Thanks Rick for the link, very helpful. I am not entirely new to photography, I used to take a lot of pics about 27 or so years ago and used a Practica camera and used a UV and a polarising filter, but that was a long time ago and I am finding the world of digital photography a bit overwhelming. Once you would stick the film in the camera set the film speed and all you had to worry about was aperture and shutterspeed and focus. Now there are about a zillion things to take into account and then you get to play with your photos on your computer, which at the moment has me completely baffled (I have GIMP2 and Photoshop CS2 if anyone has any tips) Anyway I an determined to keep banging my head against the wall until I get where I want to be. Thank goodnes for this forum!!!!!

[ricktas]

with film a UV filter was often recommended. Digital camera sensors have a thing called a low pass filter that sits right on top of the sensor and this eliminates most UV, so UV filters that attach to the front of the lens basically serve no purpose on a digital camera. They can be good if you shoot in sandy and windy, or sandy and wet environments to protect your lens, but the modern lens coatings do a damn good job of that anyway. So I would not recommend a UV filter at all. Certainly your CPL, graduated ND and ND filters are great for the land/sea scape photographer.

As for Gimp and Photoshop. Youtube is your friend, there are great tutorials on there for beginners. Just seach photoshop cs2 for beginners for example and the videos will take you through things as simple as opening and saving files to how to straighten horizons and clone out that bit of rubbish etc.

We also have this: http://www.ausphotography.net.au/for...shop-Tutorials for some photoshop help, some tutorials might be a bit beyond your experience but have a look back through them all and there are some great ones in there.

[ameerat42]

With GIMP and CS2, determine what you would like to do to an image. If you can't find out how, then ask.
I will say, though, that though both programs do much the same thing, their approaches vary. After using
Photoshop for years (now up to CS2 like you) I found GIMP's methods cumbersome. Just a case of what you're
used to. But I'd stick to one. Also IMO, Photoshop is the more comprehensive of the two.

Oh, and another thing about your lament: with digital, you've got to do the processing, where previously you
took the shot and (generally) left it to others. Welcome to a WHOLE approach in imaging

[Machiavelli]

with film a UV filter was often recommended. Digital camera sensors have a thing called a low pass filter that sits right on top of the sensor and this eliminates most UV, so UV filters that attach to the front of the lens basically serve no purpose on a digital camera.

My Nikon D5500 doesn't have a LPF - does that mean I would benefit from a UV filter?

M.

[William W]

with film a UV filter was often recommended. Digital camera sensors have a thing called a low pass filter that sits right on top of the sensor and this eliminates most UV, so UV filters that attach to the front of the lens basically serve no purpose on a digital camera.

And:

My Nikon D5500 doesn't have a LPF - does that mean I would benefit from a UV filter?

Good question.

I think the answer is: probably some benefit in some shooting scenarios. Especially when shooting in bright sunlight. In this case you’d probably get UV reduction (though the Nikon Sensor probably is not as sensitive to UV as some film emulsions were/are) and also there’d probably be a benefit in reducing some Chromatic Aberration. Thought it might be difficult to ever see a difference in most other shooting scenarios.

I think Nikon’s logic to omit the OLPF in those models, (the 5300 is the same I think), was to get greater/better resolution.

Omitting the OLPF would, I think, result in a more noticeable and prevalent issue being: Moiré Patterning.

A common occurrence when shooting Portraiture and the Subject(s) is/are wearing silk or other very fine sheen-like fabric or a very tight weave pattern on a their garment.

Moiré Patterning can be (usually is) hideously difficult to remove in Post Production.

Example of Moiré Patterning is here (the oval/circular patterns formed on the footpath’s metal grates):


“(Not so) Smart Car” - Paris 2012

WW

Image ©AJ Group Pty Ltd Aust 1996~2015, WMW 1965~1996

[ameerat42]

(Aside: I must say, WW. You'd really need PP skills to get out of that bind!)

[Steve Axford]

No problem. In Paris it is customary to park with no brake on, so others can move your car if needed. You just push the other cars out of the way. Most cars in Paris seem to have dents - I wonder why?

[William W]

. . . In Paris it is customary to park with no brake on . . .

Ta.

I didn't know that.

WW

[arthurking83]

...... Digital camera sensors have a thing called a low pass filter that sits right on top of the sensor and this eliminates most UV, so UV filters that attach to the front of the lens basically serve no purpose on a digital camera. .....

The filter isn't actually just one filter.
It's a stack of filters one on top of the other.

My Nikon D5500 doesn't have a LPF - does that mean I would benefit from a UV filter?

M.

So no! no benefit other than that already mentioned where in very severe conditions the added protection could be handy.

But in terms of UV light through the lens to the sensor and hence on your images, the benefit of a UV filter will be close enough to zero to not make a difference.