Jawed
Topic Author
Posts: 312
Joined: Mon Sep 18, 2006 10:47 am

Dust-spot Photoshop Question

Tue Jan 08, 2008 4:37 am

I found this blob in the same spot on all of my images today:

http://i215.photobucket.com/albums/cc178/javvypics/dust.jpg

I think it is safe to assume that is a dust spot.

Could you explain the best step-by-step instructions for removing such a dust spot in Photoshop? Should I use the clone-tool to copy a nearby sky patch over it? Or is there a better way?

[Edited 2008-01-07 20:38:44]
 
JakTrax
Posts: 4647
Joined: Thu Jun 30, 2005 3:30 am

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 6:26 am

Clone tool or spot healing brush. It's a classic perfectly spherical dust-spot so simply adjust the size of the clone stamp/spot healer until it's just a bit bigger than the blemish, then apply with a single click. If it looks OK, great, but you may (may) have to re-adjust the size of the brush (i.e. make it much smaller) and smooth the edges.

One thing I've wondered - is correcting dust-spots in this manner acceptable? Surely this is classed as photo manipulation and therefore a bit of an A.net taboo?

Karl
 
Jawed
Topic Author
Posts: 312
Joined: Mon Sep 18, 2006 10:47 am

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 6:28 am

Thanks that worked. I believe I have heard others here recommend removing dust spots before submitting to A.net.
 
waketurbulence
Posts: 1264
Joined: Sun Apr 18, 2004 12:33 pm

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 7:33 am



Quoting JakTrax (Reply 1):
One thing I've wondered - is correcting dust-spots in this manner acceptable? Surely this is classed as photo manipulation and therefore a bit of an A.net taboo?

Nothing about removing dust spots is taboo, even on Anet.

Quoting Jawed (Reply 2):
I believe I have heard others here recommend removing dust spots before submitting to A.net.

If you don't your photo will be rejected for "dirty." Dust spots get through screening but not often.
-Matt
 
Stealthz
Posts: 5546
Joined: Wed Feb 02, 2005 11:43 am

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 8:31 am

Karls advice is valid but basic,
I would put money on your original image having more than one dust spot*

The most effective way (apart from keeping your sensor clean) is to make a duplicate layer -
-LAYER/DUPLICATE LAYER (you can rename this layer when prompted but no real need)
Equalise this layer-
-IMAGE/ADJUSTMENTS/EQUALISE, you should now have a bizarre "Pop Art" looking image but the dust spots will be clearly visible-
Switch the active layer back to the background-
- In the Layers dialog box click on the "Background" layer, this should then turn blue.
The image on the screen will still be the equalised "Background Copy" layer but any editing will affect the "Background" layer.
-Select an appropriate sized and shaped clone tool(or healing brush) and go around stamping out the dust spots.
-When you think you are done you can hide the "Background Copy" layer by clicking on the "Eye" symbol to the left of the layer name.
-Equalise the "Background"layer and see if you got all the spots, if you are satisfied Undo Equalise and delete the Background copy layer.
If not satisfied Undo Equalise, Unhide the "Background Copy" layer and repeat the cloning process until happy.


Cheers

Chris

* that is a safe bet because I equalised it and had a look, there is one just above the nose and likely more on your original!
If your camera sends text messages, that could explain why your photos are rubbish!
 
dendrobatid
Posts: 1645
Joined: Sat Nov 06, 2004 3:40 pm

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 8:49 am

Chris's method is the best way to do it and, whilst it sounds log-winded, it only takes a few seconds to do. I do however do things slightly differently.
Before equalising I use the magic wand to select the sky and then simply equalise that. It is impossible to miss dust spots that way. Once they have been dealt with, right click, select the inverse and sharpen. That way you are simply sharpening the subject not the noise or grain in the sky. It can make a big difference if the sky is slightly noisy to not sharpen it !

Mick Bajcar
 
JakTrax
Posts: 4647
Joined: Thu Jun 30, 2005 3:30 am

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 9:05 am



Quoting Dendrobatid (Reply 5):
Before equalising I use the magic wand to select the sky and then simply equalise that. It is impossible to miss dust spots that way. Once they have been dealt with, right click, select the inverse and sharpen. That way you are simply sharpening the subject not the noise or grain in the sky. It can make a big difference if the sky is slightly noisy to not sharpen it !

Wow! You learn something new every day! So simple but I would never have thought about doing that. Cheers Mick.

Karl
 
User avatar
dvincent
Posts: 1486
Joined: Mon Jan 01, 2007 9:53 am

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 1:47 pm

I use the same method as Chris as it's very effective and has been around for a very long time in the scanning circles. I learned it years ago from a drum scanner operator.

My suggestion for the tool of choice (which has been mentioned in here) is the healing brush. The reason the healing brush is (In my opinion) more suitable to dust removal is that it only modifies the luminance of the cloned area. Dustspots are a luminance issue when you get down to it (hence why equalize makes them show up) and the healing brush is the perfect tool to take them out. This means you don't have to worry as much about the clone source, as you won't get any "clone circles" of obviously cloned areas.
From the Mind of Minolta
 
Jawed
Topic Author
Posts: 312
Joined: Mon Sep 18, 2006 10:47 am

RE: Dust-spot Photoshop Question

Tue Jan 08, 2008 5:55 pm

thanks these are great tips. using the magic wand to select just the plane for sharpening makes a lot of sense.

what is the main difference between the magic wand and the quick selection tool?
 
Scotland1979
Crew
Posts: 331
Joined: Sat Feb 12, 2005 3:19 am

RE: Dust-spot Photoshop Question

Wed Jan 09, 2008 1:28 am

Wow! I haven't tried what Mick Bajcar's quote. I should try some day.
Speaking of healing brush, sometimes I used this to remove dust spots. However, I have struggled to remove just one dust spot from one photo again again again - seem not work. So I will try Mick's
Jesus said "I am the Way and the Truth and the Life. No one comes to the Father except through Me" - John 14:6

Who is online

Users browsing this forum: No registered users and 5 guests