View Full Version : Doing ND Graduated filters in post processing

09-05-2010, 11:31pm
One question I get asked a lot is whether I use graduated filters when shooting sunrises and sunsets. Well, the answer is 'Yes I do, but not always'. When I'm out in the predawn darkness, trudging around in the mud, I don't really feel like changing lenses and mucking about with filters, so the alternative is to achieve the same effect during post processing.

To do this in software we need to take some bracketed shots, making sure you have at least one shot exposed for the foreground and one shot exposed for the sky.

Exposed for the foreground:

Exposed for the sky:

Now, let's get to work.
I use Paintshop Pro. Adobe users, you will have similar features, just slightly different.

STEP 1. Starting with your darker image, paste in a copy of your lighter image as a new layer

STEP 2. Right-click the top image and select 'New mask layer'.

What you'll end up with is something like this:

STEP 3: Click on the mask layer to select it.
Now everywhere we paint black on the mask will allow the darker image to show through. To get the same effect as a graduated filter, I'm going to use the gradient fill tool to paint a gradient in the mask layer

Well, that's better, but the tops of the buildings and the trees are too dark.

In real life, we'd rotate the graduated filter a little, so let's do the same with our gradient fill:

Perfect! And here's the result:

You can use this technique for any situation where a graduated filter would be used:


10-05-2010, 5:21am
I have always been a fan of masking and graduated masking. Your tutorial is very handy for those wanting to give it a try. Simple layout and well written. Thanks.

10-05-2010, 5:59am
Thanks David - will give this a try ...

10-05-2010, 6:11am
Good work with the tutorial David, thanks for sharing

old dog
10-05-2010, 6:50am
thanks david...will try this out.

10-05-2010, 7:46am
Thanks guys. I have recently had several people on this forum and out at flickr meets ask me about exposure and using filters for sunrise. So I figured the best solution would be to write a tutorial.

10-05-2010, 12:58pm
very nice !!! Looking forward to using these methods in the event I dont have my filters with me

10-05-2010, 1:08pm
That's a very well writen and illustrated Tutorial - many thanks David

10-05-2010, 8:12pm
Fantastic. Thanks for sharing. Have looked around for a good digital grad filter technique. This is the best thus far!

10-05-2010, 8:47pm
Good little tutorial.

10-05-2010, 9:18pm
Good work David.

Unfortunatley my choice of processing software does not allow this kind of processing. May sound like a bad thing to the average punter, but is in fact a good thing(to the above average punter :p)! :th3:

filters are always with me.. come rain(great starlet effects :th3), hail(good protection for the lens :p), sunshine(funky hazy flare effects)... gale force winds(great for watching your $40 pride and joy fly off into the distance and over a 300m high hill side.. right out of your hand!)... otherwise I go home.

10-05-2010, 9:40pm
Thanks guys, glad you found it a good read.

Arthur, you have far more patience than me and the results show in your images. I guess the ability to do this sort of processing is just an alternative to the traditional method ... (I can here Maxwell Smart's voice here) ... as long as we use our PP software for goodness and not evil :)

11-05-2010, 4:38am
Thanks David, looking forward to putting your techniques to good (not evil) use :D

11-05-2010, 6:20am
For those that have it, Nik Software Color Efex has a very good ND grad filter in it as well.

11-05-2010, 6:34am
Thanks David: very clearly explained, so well explained even I understood how it works.

11-05-2010, 11:06am
For those that have it, Nik Software Color Efex has a very good ND grad filter in it as well.
Thanks Rick.

Thanks David: very clearly explained, so well explained even I understood how it works.

cool! :th3:

07-02-2011, 6:22pm
I must admit i prefer to use filters in the field rather than photoshop but that is mainly due to not knowing how to utilize it properly; however following your tutorial i think i'll be giving it a shot, it appears very effective

08-02-2011, 5:33pm
Thank you for the tutorial.

Dylan & Marianne
09-02-2011, 7:34am
well explained and applicable to CS5 with a few tweaks as well - great results too from the shots you've got up there.
The only thing about software GND effects though is that you can't as easily repllicate filters like hard stop GNDs and reverse GNDs - hence I usually prefer to GND in the field in addition to any further adjustments like this afterward.

09-03-2012, 12:03am
sounds great. hopefully saves me from getting a nd filter ^^