Managing tone

The aim of this exercise was to explore how to alter tones of an image using processing software. I have always used Photoshop for  JPEG images and Digital Photo Professional for RAW. I researched altering a RAW image in Photoshop. Although previously I made changes to images in Photoshop through curves, I discovered that I hadn’t made the connection between the highlights, shadows and midtones and decided to investigate further at this point.

Following on from the last assignment work, I wanted to look at a low contrast images so I started with a photo taken on a misty morning of a cement works in the distance looking across the fields.

Original


F16 1/45 ISO100 32mm  (x1.6 crop factor) partial metering
daylight white balance

JPEG

Opened in Photoshop CS3
> Adjustment layer curves 1
> select clipping
> set black and white points
> altered curves based on preset lighten > check > further lightening required by moving the curve freehand
> crop
> flatten image
> save
I looked at altering the colour temperature (white balance) for this image and decided it did not require any changes to be made for my personal taste.

What I learnt from this exercise which I did not do/know beforehand:

• I used to add a duplicate layer to work in. I discovered that to set the adjustment layer of curves opened the curves box (time saving)
• A tutorial I read suggested that if the clipping box is ticked, the slider can be moved until pixels start to appear. This sets the white and black points accurately.
• There are preset curves which give an idea of how the image may look if you lighten or darken the image using curves.
• The graph has three points where it can be altered and what each point referred to. Watching the histogram as the curves were changed gave an idea of what was happening to the image.

RAW

I had not worked in Photoshop with a RAW image before, but discovered limitations with my existing software. Once I found my way around the layout, it was straightforward.
> Opened in Photoshop CS3
> Select tone curve
> Select parametric (sliders) to lighten image whilst observing image/histogram
> Highlights +55
> lights –7
> darks +28
> shadows –5
> Reviewed original image
>changed to point (tone curve) to check image (graph)
> crop
> save

I found it easier to use the tone curve than the 1st set of sliders for this image.

Overall, I prefer the RAW conversion because it is how I remember the scene to look. The mist is more even and the greens of the grass are less bright. I think in this instance, I achieved a more pleasing result.
                                                               
Bibliography
http://www.cambridgeincolour.com/tutorials/photoshop-curves.htm accessed 30/9/13
http://www.digitalcameraworld.com/2013/03/18/photoshop-curves-tool-6-techniques-every-photographer-must-know/7/ accessed 30/9/13

Managing colour

This exercise involves looking at photos with a significant colour cast and “correcting it”.  My usual preferred software is Photoshop for JPEG images and Digital Photo Professional for RAW. I decided to process the images using this known software.

Image 1

This photo was taken on a misty morning where I had left the white balance set to daylight giving the image a blue tinge.

Original
1/125 F3.5 ISO200 18mm partial metering daylight white balance
partial metering– sky cropped (x1.6 crop factor)

JPEG
JPEG blacks set on histogram - grey dropper tool in curves
touched on mudguard –  sky cropped 

 

RAW
RAW blacks set on histogram – white balance altered
 to cloudy – sky cropped



By warming up the colour, the blue of the rucksack became slightly yellower in colour. The T shirt reverted back to brown instead of looking black. There is not much difference between the jpeg and RAW. If anything, the RAW looks more natural.

Image 2

This has a significant green tinge to it.

Original

1/15 F4.5 ISO100 24mm (x1.6 crop factor) 

daylight white balance evaluative metering 

JPEG

The JPEG image was altered using the grey dropper tool. I did not expect to find any grey, but clicking on various rocks on the path changed the colour.




RAW

To alter the RAW image, the white balance tool did not help at all because the colour was already warm. Using the RGB tone assist on my RAW software, I was able to select the individual colours and increase or decrease them. Blue – increased, Green – decreased, Red – decreased.

I prefer the RAW image colours as they are warmer and I had more control over the image.

Image 3

This was a location shot  (JPEG only)for reference for a previous assignment. The sky was heavy with snow so I had taken a smaller camera out to record the location.

1/800 F4 ISO400 evaluative metering, auto white balance

By sliding the black and white parameters inwards as it is a low contrast image and using the grey dropper tool on the grey foreground snow, the colours have changed from a grey tinge on the snow to white snow.

In summary, I realised how colour cast can easily be managed. I  found that a few images which I had left on my computer unedited because I wasn't quite sure what to do with, could be improved quite easily. The process for editing a JPEG and a RAW image was simple, and with patience, I am sure my images could both look more similar. My feeling is that it is still better to get it right in camera where possible.