Assignment Two - Photoshop

Image Size vs Image Quality

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Here is showing the comparison from shrinking an image. Both images are JPEG images and saved at the  highest quality available, the only difference between these images is one has been saved at a smaller size than the other. From viewing the image at both sizes it shows that as the image size shrinks the detail in the image is affected, the bigger image is showing a  much better payoff of detail. The smaller image has held up quite a good bit of detail as you can still see what the image is and there is only a slight loss in image quality.

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When shrinking images it is seen that the quality is affected,  although in these images do not show the full effect of this. If you were to continue to shrink this image more the quality would diminish rapidly, leaving an image that you cannot distinguish anymore. 

Image Quality 

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This is the comparison of two images of the same size saved at different qualities. The first image is saved at the highest quality where you can still see the words "first republic" written on the building, in this image you are still receiving a high enough quality despite the size.

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In the next image it was saved at the lowest quality. You can see that the words written on the side of the building have become nearly illegible and the quality of the image has deteriorated rapidly. Although you can still make out what the image is other than the words "first republic" written on the side of the building, if this was to shrink any smaller you would be unable to distinguish the image compared to the other image which would hold the detail of the image longer despite the size.     

Gif's Dithering vs No Dithering

The image below shows two images. The first image is a gif with no dithering the other is the same image with 100% dithering applied. Both images pay off the same amount of detail but the dithering allows for the file to be saved at a much smaller size while still saving the quality. Dithering is used in images to display a colour image in such a way that it appears to contain more colours than are really available. Although it cuts down on the colours available it still holds the detail.

Colour vs Black & White

The image below is the first original image except it is black and white. Although you are able to save this image at a much smaller size due to the lack of colour it would not be a recommended way to save your image. Although the image does hold up the detail produced in the first image, if the image was to change to something which would require colour to convey the message it was supposed to produce it would be unable to do it black and white.


From reviewing the different types of images and which produces the best quality etc, I would recommend sticking with the JPEG image. It holds the full range of colours needed to convey any message and can be reduced in size while still holding most of the detail without needing a large file size to convey the detail in the image.

From a web developers perspective they need to get the maximum quality from the smallest file size for convenience. They need to be aware of what file type to save the image as to produce the image needed for example if it was a logo with a few colours a dithered image would provide the quality needed for the logo without the developer needing to save a large file to produce the same image.

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