# Filters and filter techniques in post processing



## Hoss (Jan 2, 2010)

A lot of great discussion got started in this thread.

http://forum.gon.com/showthread.php?t=466173

I'd sure like to see it continued.  I believe there are a number of folks who would like to know more about both.

Hoss


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## xs5875 (Jan 2, 2010)

I have heard that in the day and age of digital post processing...filters really arent needed. But I like to get it right IN-CAMERA, so I use them. Like yesterday I was using a polarizing filter to keep my skies blue and greens crisp...and it works!


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## JasonF (Jan 2, 2010)

Thanks Hoss, I almost started this same thread but shared my view on the other instead.  Hopefully we can a good discussion going!


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## JasonF (Jan 2, 2010)

_My take of filters...taken from the thread in the link provided by Hoss:_

The use of filters is a personal decision, however, you cannot argue the effectiveness of filters for protecting your valuable lenses or the fact that the effects of a polarizer cannot be duplicated in post processing like DRB stated.

The real debate, in my opinion, lies with the use of graduated neutral density filters (GND) or regular neutral density filters (ND). 
ND filters help create affects that can sometimes not be produced without...blurring water for example. Yes, sometimes you can achieve the desired look when shooting in low light situations, but there are times when using a ND filter will help create the look your after.

GND filters can be mimicked in post processing and by bracketing and blending in pp. I, for one, prefer to get the exposure right, in camera, the first time instead of blending in photoshop...the result is a much more realistic and true scene.

As someone who has used both methods, I prefer the look of a filter over the post processed look. 
Again, the use of filters is strictly a personal decision and I won't now leave home without them in my bag. 
In today's digital world, It's the photographers duty to use all necessary available tools to get the shot, weather it be the use of filters, or photoshop...pick your posion.


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## xs5875 (Jan 2, 2010)

Ahhh yes JasonF, if I recall correctly you used a graduated ND filter for your "Drama" beach shot?...that is perfect supporting evidence for the use of filters in "Outdoor-Scape" Photography...Sometimes there is too much light to obtain a slow shutter speed when shooting say a waterfall, so the ND filter allows you to filter out that excessive light and get the shutter speed your looking for..


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## JasonF (Jan 2, 2010)

For the sake of getting this thread going and to help others learn the differences between using GND filters and blending...some examples.

Now, I just got the GND and this was my first time out with it and furthermore, I am not the greatest at digital blending so take my examples for what they are worth.
First off, digital blending (in photoshop or like software), to me is a blend of two shots, one exposure of a scene for the forground and one for the sky.  A blend of 3 or more is an HDR image.  I have zero experience creating HDR and really that is maybe a topic for another thread.

Both example are of a different scene but are both a sunrise with a dynamic range too widespread for the camera to capture by itself...the solution.

A: Graduated Neutral Density Filter (3 stop filter in this case)







B: Digital Blending (2 exposures taken of the scene and blended in photoshop)






You may draw your own conclusions from the results above but I can tell you the first image was straight from the camera other than a saturation boost & minor cloning of flares and dust.
The second image took far longer in pp to produce but with similar results.
Again, it's a personal preference as to which method you prefer.  

Thoughts?


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## Crickett (Jan 2, 2010)

Great thread! 

I only use a UV filter right now. I've looked at others but I am comletely clueless when it comes to filters. I am looking forward to others chiming in w/ there input.


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## xs5875 (Jan 2, 2010)

Yes the 1st image probably could have been duplicated without a filter, but as you said with an HDR..but it would have had that "artsy" feel...I think you nailed it and done it the right way...


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## JasonF (Jan 2, 2010)

Crickett said:


> Great thread!
> 
> I only use a UV filter right now. I've looked at others but I am comletely clueless when it comes to filters. I am looking forward to others chiming in w/ there input.



The UV filter is a great insurance policy for your lens so it's one to have in the bag or on the lens.  The next step Crickett would be a polarizer filter.  
Slap a polarizer on your lens and take it down to the mill by your house and it'll do wonders with little practice.  Polarizers are typically 2 stops so you can also use them to help slow the motion of water too.


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## Hoss (Jan 2, 2010)

Great examples, Jason.  I believe you have provided a great example of being able to get photos using both methods.  I think the first likely could not have been duplicated by combining images.  The wave motion would have made it impossible to line up.  If anything is moving in images, combining images would be a real challenge.

Hoss


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## Crickett (Jan 2, 2010)

JasonF said:


> The UV filter is a great insurance policy for your lens so it's one to have in the bag or on the lens.  The next step Crickett would be a polarizer filter.
> Slap a polarizer on your lens and take it down to the mill by your house and it'll do wonders with little practice.  Polarizers are typically 2 stops so you can also use them to help slow the motion of water too.



Thanks for the info Jason. I'm pickin' up a tripod from a fellar on here tomorrow. I will put that filter on my wish list. I gotta birthday comin' up so maybe I will get some stuff from that list.


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## JasonF (Jan 2, 2010)

Hoss moving subjects within the frame definately make blending more difficult however, there are a few different blending techniques in which I could have created a blend of the first image without touching or interfering with the water.


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## jasonyoung (Jan 2, 2010)

My argument against filters acting as extra protection is dont drop your camera! 

I have no argument on the rest.


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## JasonF (Jan 2, 2010)

jasonyoung said:


> My argument against filters acting as extra protection is dont drop your camera!



If you drop your camera your gonna need a whole lot more than a filter to save it.


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## DRB1313 (Jan 2, 2010)

A little more on Polarizers:

First, for you Cricket.  You will want a two stop Circular Polarizer.
When you screw it on the lens, you will notice there is a second ring that lets
the filter spin.  This is because it it adjustable.
As you look through the viewfinder and spin it, you will see it go from light to dark. (Darker being the stronger setting).
I usually turn it until it's at it's darkest point and back off just a hair.
Also the effect of the filter is greatly increased with the location of the sun.
It works the best when the sun is at a 90 degree angle, or to your left or right vs.
behind you or straight up.

The one thing a Polarizer can do is take glare or reflections off of reflective surfaces like water and glass, however,
it will not work on metallic surface. I don't know why.
You cannot reproduce this effect with photoshop.

So, What does this mean, well let's say you want to take a photo of fish in the water or capture the colorful rocks on the bottom
of a stream. This is where a Polarizer does it's magic.
Like polarizing sunglasses.
Another instance would be, if you were taking a shot of someone near a window and
you did not want the reflection of the trash pile behind you in the photo.

But the best use for a polarizer is taking the glare off of leaves and adding a beautiful contrast of colors to a nature scene.


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## jasonyoung (Jan 2, 2010)

JasonF said:


> If you drop your camera your gonna need a whole lot more than a filter to save it.



Trust me, I already know! 

When Nikonreturns your D300  unfixed with a note that says "Beyond Economical Repair" you get that gut feeling that ya shouldnt have dropped it!


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## Hoss (Jan 2, 2010)

JasonF said:


> If you drop your camera your gonna need a whole lot more than a filter to save it.


 
No Jason, that's not the case.  You just won't ever get the filter ring off again and the glass from the filter won't be there anymore.  Don't ask how I know this.

Hoss


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## Crickett (Jan 2, 2010)

DRB1313 said:


> A little more on Polarizers:
> 
> First, for you Cricket.  You will want a two stop Circular Polarizer.
> When you screw it on the lens, you will notice there is a second ring that lets
> ...



Thanks David!


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## JasonF (Jan 2, 2010)

Great post DRB!!
The polarizer, is IMO, the #1 filter to have in your bag!!


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## JasonF (Jan 2, 2010)

jasonyoung said:


> Trust me, I already know!
> 
> When Nikonreturns your D300  unfixed with a note that says "Beyond Economical Repair" you get that gut feeling that ya shouldnt have dropped it!



Ouch!!! That hurts just reading it!



Hoss said:


> No Jason, that's not the case.  You just won't ever get the filter ring off again and the glass from the filter won't be there anymore.  Don't ask how I know this.
> 
> Hoss



Double ouch!!


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## Crickett (Jan 2, 2010)

JasonF said:


> Great post DRB!!
> The polarizer, is IMO, the #1 filter to have in your bag!!




I use to have one along w/ some others back when I had my Canon Rebel 2000 but I sold the camera a while back & everything w/ it.


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## JasonF (Jan 2, 2010)

Crickett said:


> I use to have one along w/ some others back when I had my Canon Rebel 2000 but I sold the camera a while back & everything w/ it.



Well, just be sure when you get a new one to buy the best quality filter you can afford.  
B+W filters are the cream of the crop for screw on filters but they are pricey.
Hoya also makes good filters...just not as good as B+W.  I bought my polarizer (Hoya) off of Craigslist used for $20  and it does the job for me.


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## DRB1313 (Jan 2, 2010)

Jason, I shoot with B+W's, They should have called them BMW's

They are real proud of them ,but I wouldn't trade them for anything.


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## Crickett (Jan 2, 2010)

DRB1313 said:


> Jason, I shoot with B+W's, They should have called them BMW's
> 
> They are real proud of them ,but I wouldn't trade them for anything.






Yeah I've seen those on the B&H website. I will have to save up for one of them. Maybe I will luck up & find a deal on CL.


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## JasonF (Jan 2, 2010)

DRB1313 said:


> Jason, I shoot with B+W's, They should have called them BMW's
> 
> They are real proud of them ,but I wouldn't trade them for anything.





They are well built aren't they!!!
I've got a 2 stop B+W ND filter...it's a tank!


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## Hoss (Jan 2, 2010)

So what can you do with post processing filters?  I grabbed a photo I took last summer and simply applied a cooling filter to it in PSE7 (Cooling filter 82 from the Filter-Adjustments-Photo Filter drop down)  I've used these a bit when I want to cool or warm up a photo.  The first photo is the original and the second is with the filter.

Hoss


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## Crickett (Jan 3, 2010)

Pretty cool demonstration Hoss!


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## JasonF (Jan 3, 2010)

Great example Hoss!
I use the cooling filters in Photoshop too...they come in handy at times!


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## Freddy (Jan 3, 2010)

I wish I had something to add, unfortunately I am in the learning mode here. I do want to thank you all for your input as it is very valuable information. One question I still have, are there any filter tools in PSE which will aid in reducing haze or smog? I have a bunch of pictures from a recent trip to Mexico which could use some work.


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## JasonF (Jan 3, 2010)

Freddy, I'm not sure if there is anything to fix that but the best way to find out is to post a picture and allow some of the guru's to play with it.


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## Freddy (Jan 3, 2010)

Ok, here are some examples.This picture is not great but actually the smog was pretty severe so it shows the extremes. Photo 1 is the original,  Photo 2 has a cooling filter and unsharp mask applied, and photo 3 uses the technique from this link http://onlinephototutorials.com/2008/08/03/remove-haze-from-landscape-photos/. The question is, can it get any better or is this about what I should expect.


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## JasonF (Jan 3, 2010)

Freddy, to my knowledge,there are no filters in Photoshop that can fix the smog in your pictures.
I did play around a bit and was able to remove the smog in the lower right using the clone tool.  I also darkened the mountain using the burn tool thus removing the haze look to it.  To make a flawless effort to remove the smog would take more time and I just ran through the motions real quick...but hopefully you get the picture.  
Maybe someone else will have a more effective way to fix these for you.


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## leo (Jan 3, 2010)

Freddy.... here is a very quick "fix" in PSE 6, of course working in raw, or with the origional pic would give more results here is your 1'st pic with only a bit of lighting adjustment ....   just to give you a idea of PSE abilities


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## GAranger1403 (Jan 3, 2010)

Cool thread, we should make a book out of all the technical threads here. I am constantly going back and looking for technical/tutorial info on here. Thanks to everyone!


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## 57bronco (Jan 3, 2010)

I always put a UV filter on a lens when I buy it, but the only filters I use are B+W. I have two lens that are $2000 each and I've seen a sudden blast of sand come up and without the UV I might be worried.
I also have a couple of Polarizing and ND filters I use. I try to get the shot, with as little editing as possible, so filters are a plus for me.


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## JasonF (Jan 3, 2010)

Looking back at my attempt to edit your shot Freddy, I could have done better.  I went a little heavy with the burn tool but really if you add a touch of contrast and clone out the smog in the sky, I think it might be closer to what you were after.


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## leo (Jan 3, 2010)

Hoss, glad you revived this one, I have accumulated a few filters, other than the UV protectors, but rarely take the time to use them enough to be familiar with them.......


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## Freddy (Jan 3, 2010)

Thanks everyone for the help and the advice. I also know a couple of folks are still working on this. If anyone else has any experience with removing smog I would love to hear it.


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## Hoss (Jan 3, 2010)

OK, I cheated a little and had Freddy send me the full resolution photo.  I just couldn'g get what I wanted on the one from the thread without everything pixelating.  Here's what I ended up with.  Thirteen steps in the process (actually a lot more with all the undos).

Hoss


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## Freddy (Jan 3, 2010)

Hoss, that is much better than mine. I think now you should give up the secret formula. I think this may have been an extreme example but I figured if this one can be cleaned up than maybe others that are not so bad can be made to look nice.


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## Hoss (Jan 3, 2010)

I've been working on it Freddy.  Here's the instructions in a pretty brief form. 

PSE7 instructions
Open photo in editor.
Select Remove Color Cast from the  Enhance – Adjust Color menu.  Follow the directions to remove color cast.
Select Shadow and Highlights form the Enhance – Lighting Menu.  Adjust lighten shadows all the way to the right, Darken highlights to center and Midtones to the right.  You want a very blue (unnatural) looking sky.
Add a  levels layer.
Select Place from the File menu.  Select the same photos as you are working on and select check.
From the layers menu, select Group with previous.
Select Adjust color curves form the Enhance –Adjust color menu.  Adjust curve to provide a normal slightly blue sky.
Select the levels layer and then select the gradient tool.  Select Black White gradient, Mode –Darken, Opacity 100%.  Now starting at the bottom of the photo, draw a vertical line to near the top of the photo.
Flatten the image
Select Photo filters from the Filters – Adjustments menu.  Select warming filter 81
Repeat the remove color cast step.
Create a new duplicate layer.  From the layers drop down menu, select Hard light.  Adjust the opacity of this layer to 45-50%
Save.

For the image that I posted, I resized to 1000 x 750 pixels, sharpened and did a noise reduction on the sky.

I suspect the process can be simplified.  I really thought I could get there without the last few steps and with some tweaking, steps could possibly be removed.  The addition of the warming filter was a bit of a surprise, but it removed more of the smog with the last color cast removal.  It might be worthwhile to try that step before the first color cast removal. 
Also, a raw image may be easier.  The steps using the place function and gradient tool are a method of creating HDR type photos from a single image.  Using raw files, you could adjust the exposure between the two identical images you are working with to eliminate more of the smog with this step I think.
Let me know if any of the steps need to be discussed in more detail and if anyone finds some shortcuts, please share em.

Hoss


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## Freddy (Jan 4, 2010)

Wow, thanks a bunch Hoss. Unfortunately I gotta head bad to work today. But, I can't wait to try the instructions as this is much deeper than I have gone in the past.


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