EXERCISE: Correction

Part I:

Look through your image collection and try to find one containing dust shadows and another with polygon flare.  If you can’t find examples of each, use the images provided in the Key Resources section of the Student Website.

Beginning with dust correction, there are now specific tools in all processing software, be it Photoshop, Lightroom, Aperture, DxO Optics or any other.  Scroll through the image at 100% magnification identifying dust specks and removing them.  All of these tools, whatever the software, work by attempting to replace the area of the dust speck with the texture, tone and colour of its immediate surroundings.  This is, therefore, actually altering the content of the image, although on such a small and trivial scale that few people would argue against it.  Where the dust speck is in an area without nearby sharp detail the tool works very well.  But if the dust speck is only a few pixels away from detail, or even sits on top of detail, you may find the results less satisfactory.

More effective in this situation is the clone stamp tool, but you will now find that you have to make more of a conscious decision to replace the small area with something specific.  Is this as ‘innocent’ a correction as using the dust removal tool?  Also, if you work over an area of the image that includes random specks of similar size to dust, as in the example, you will have difficulty deciding whether a mark is dust or content.  This raises another valuable consideration – is this particular speck real from the scene, or an artefact caused by dust on the sensor?  Should you remove it?  Does this bother you?

I actually use the spot healing tool in Photoshop often – before I started using Photoshop, I did the same in iPhoto.  I have an issue with my camera in that I appear to have many marks on my sensor; something that has been there since I brought my camera, and something I had to contend with on my first Nikon.  This issue has become more apparent recently, especially as I am beginning to use longer shutter speeds, which tends to make the issue worse due to the sensor being open to the light for longer.  Next week, I go to have my sensor cleaned – something I am not comfortable to tackle alone, and something I hope will rectify my issue.

With the above in mind, I feel quiet comfortable using this tool, so the first part of this exercise was quiet easy.

Original Image Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

Original Image
Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

I have chosen to use this image, taken of a stunt rider at our local summer fate, as I thought it an easier choice for the exercise as the sky is represented by an even colour, which highlights the ‘issue’ areas nicely.  I have not been able to access the image supplied by the OCA as I am not able to access the key resources through the new website.

Marks Identified Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

Marks Identified
Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

For ease, I have included the same image, identifying the issues that need rectifying, highlighting those I intend to use with the spot healing tool in red and those with the clone stamp in green.

As I always do, I set my healing area slightly bigger than the spots seen on the screen and the hardness to 100%.  As it does the best job of erasing the spots, I set the Mode to Luminosity.  Increasing the image to 100% always makes it easier to find the culprits, there are always more at this magnification, so this ensures I pick everything out.  Once everything was set up, I scrolled through the image and erased the identified spots.

With Dust Spots Removed Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

With Dust Spots Removed
Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

I had never really thought about this being a form of manipulation, as removing dust spots from my images is something I have always done, but as I learn more about what is and is not classed as manipulation, I can now see that this procedure could be classed as altering my work, if only by a comparably small amount.  There have been times in the past where I have not been 100% happy with the results received from using this tool, but now I understand that this procedures copies pixels from the surrounding area, I can see how the programme could get confused, thus healing the spot with unwanted information over the correct data.

Next, I moved on to using the clone stamp tool, something I had not done before, so I had to conduct some research into its use.

As you can see from my reference image, I did not leave myself too much work here, but I did have quiet a large area, below the rear wheel, which I could not get right using the clone stamp, so this was a prime opportunity to see how I could get the app to work.

Cloning the spots was easy, once I got my head around how this application worked.  I found that by selecting the pixels directly above the dust spot made a good transfer of information from one place to the other.  On the other hand, the long mark was more difficult to erase, as I needed to blend the colours from different areas, this was achieved using brush strokes over simple spots.   During my research, we were advised to use a medium sized, soft brush as this would make the blending much easier, and now that I have conducted the exercise, I can see that this is so.  By painting small areas, then changing my cloned area, I was able to erase the mark with relative ease, although it took much longer to do than erasing the spots.

The final image looks great; I am pleased with the results.

Final Image Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

Final Image
Shutter Speed 1/1600; Aperture F5.6; Focal Length 300mm; ISO 400; Spot Metering; AWB

The coursework asks:

         Is this as ‘innocent’ a correction as using the dust removal tool?

and I think the answer has to be that it depends on what you are looking to remove from your image, especially as this application is a defined pixel transference as specified by me, the user.  Again, this really boils down to integrity.  In my mind, if you are removing something like dust or an imperfection created by the camera, then in order to make both a better representation of the scene being captured and a nicer looking image, this tool will help to remove blemishes that should not be there.  However, if this tool is being used to take out something you do not want to be in the photo, or to erase imperfections of a model or old building, then there needs to be a really good excuse for its use.

Part II

Lens flare correction takes more skill and more intervention, as there are no tools specifically for this job.  There are various possibilities, including attempting to make a precise selection of the flare polygons before applying, say, a curve adjustment.  This is very difficult to achieve naturally, and I recommend a different, less invasive approach as follows:

  • Use a clone tool set to colour to integrate the flare polygons to their immediate surroundings
  • Use a clone tool set to darken, also with a close neighbourhood source

These two actions, performed carefully, should remove most of the apparent blemish, and possibly suffice for the image.

How justifiable do you think this exercise was?  If the flare is considered a mistake (this is not always the case; flare can be used creatively in composition), is there an argument that it should be left as it is?  Note the results in your learning log.

This turned out to be a very time consuming exercise.  To compare the results, I tried two different methods, both of which have turned out okay, but due to my limited knowledge of the clone stamp tool, I am sure, with time, I could get better results.

First a copy of the original image used in this exercise

Original Image Shutter Speed 1/80; Aperture F4.5; Focal Length 58mm; ISO 100; Matrix Metering; AWB

Original Image
Shutter Speed 1/80; Aperture F4.5; Focal Length 58mm; ISO 100; Matrix Metering; AWB

Originally, I intended to use a different image here, but due to my lack of experience it turned out too difficult to get results, so I decided to use this image, which has only minor sun flare.

My first process was with the mode set to the dissolve option, with my brush set to soft round, and the harshness set at zero.  I then set about meticulously working on the flare and painting in the colour, taken from the darker areas of the workout pants.  I changed the size and intensity of the brush often so that I could colour around the highlights in the back of the knees, this was the hardest part to get right.  I found it easier to work from the top down as this gave me the largest area of colour to work from as when I worked from the bottom up, I kept including the gold buttons and highlights from behind the knees.

Using the Dissolve Option Shutter Speed 1/80; Aperture F4.5; Focal Length 58mm; ISO 100; Matrix Metering; AWB

Using the Dissolve Option
Shutter Speed 1/80; Aperture F4.5; Focal Length 58mm; ISO 100; Matrix Metering; AWB

I am pleased with this result, especially as it is the first time I have used this tool, but there is much room for improvement and I think that by playing around with the different brushes and mode options more, over time it will get easier.

Next, I tried the same manipulation but with the mode set to darken; the brush type and harshness of the strokes were the same as before.

Using the Darken Option Shutter Speed 1/80; Aperture F4.5; Focal Length 58mm; ISO 100; Matrix Metering; AWB

Using the Darken Option
Shutter Speed 1/80; Aperture F4.5; Focal Length 58mm; ISO 100; Matrix Metering; AWB

It was much easier using this mode setting as it took a fraction of the time to see the results for removing the sun flare, however, the lines in this image are not as crisps as seen during the previous manipulation, especially around the back of the knee and thigh area.

As before, if given the time, I should be able to improve on this and now that I have tried out the clone stamp tool, I will not be as afraid to use this option again, as long as the circumstances are right of course!

I think this was a justifiable exercise, as it has taught us how to use the tool and guided us to see what happens to our photos when they undergo this type of manipulation (moving pixel details from one place to another etc..), but while conducting these exercises, I did feel as though I was committing a crime against my image.

When using the spot-healing tool, I am removing an issue that has been created by my camera, I know that sun flares are also an artefact, but removing them seems to have boundaries that are more ethical.  Perhaps it is because it took so long to do (spot healing takes seconds), or possibly, it is because you have to make calculated decisions about changing something within your photo, but I will always think twice before using this tool for any major alterations…

Source:

Bibliography:

Johnson, J.  (2010) The Ultimate Guide to Cloning in Photoshop [online article].  Available at: http://www.smashingmagazine.com/2010/03/30/the-ultimate-guide-to-cloning-in-photoshop/ [Assessed 8 September 20130].

Ross, J.  (n.d.) Photoshop CS5.5 Tutorial – Clone Stamp – How Not to Use It [online article].  Available at: http://www.theartofretouching.com/blog/photoshop-tutorial-cloning-stamp-how-not-to-use-it [Accessed 8 September 2013].

Ross, J.  (n.d.) Learning How to Clone in Adobe Photoshop C5.5 [online article].  Available at: http://www.theartofretouching.com/blog/learning-how-to-clone-in-adobe-photoshop-cs5 [Accessed 8 September 2013].

Smith, J et al.  (n.d.) Use the Cline Stamp Tool in Photoshop CS5 [online article].  Available at: http://www.dummies.com/how-to/content/use-the-clone-stamp-tool-in-photoshop-cs5.html [Accessed 8 September 2013].

Obermeier, B.  (2010) Photoshop® CS5 All-in-One For Dummies®.  Hoboken, NJ: Wiley Publishing Inc.

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