Monthly Display - August 2018

 

Improving the Colour Accuracy of My Photographs

I enjoy taking photographs. I enjoy the processes involved in taking the photographs and also in producing good quality images from the photographs taken. In the past, I've developed my own black and white film negatives and printed black and white prints using a good enlarger. Colour film prints were usually processed for me, and were typically quite disappointing. These days, I typically take most of my photographs using digital cameras, which typically produce digital image files in jpeg format.

One of the cameras I have is an Olympus E-30 Digital SLR. It was the best camera I had for quite a while. It was part of a large kit my father had purchased after considerable research, consisting of the camera body, 5 interchangeable lenses, flash, battery packs, memory cards, camera bags, creative lens filter sets, and a good quality tripod. One of the good things about such a camera, is that it can record its photographs using a 'raw' mode. This means that what is saved on the memory card is a copy of the camera sensor at the time the photograph was taken. Raw images then need to be processed in a computer to form their photographic images. One of the big advantages of processing raw images rather than relying just on one conversion to a jpeg image processed within the camera at the time the photograph was taken, is that raw files can be processed with a multitude of different settings. Exposures can be modified to some extent to make sure your image looks correctly exposed. Different 'White Balances' can be tried to create the range of colours you were expecting to see back. You can also apply a range of processing to fix things like chromatic aberration, sharpening, colour saturation, overall contrast, etc. The camera came with a program (Olympus Master 2) for converting the raw files to jpegs, allowing the control of various settings to get pretty good images. I since came across an improvement to that program in the form of Olympus Viewer 3. That program provided improved control of the available settings, and allowed batch processing of a number of raw files.

I used ISO 100 for all of my photographs with this camera up to fairly recent times, because in my mind, it resulted in the cleanest images the camera seem to be able to produce (with the least amount of 'noise'). I have since read a review of this camera on Digital Photography Review (www.dpreview.com) from 2009 which pointed out that the dynamic range of the camera is better when using ISO 200, rather than ISO 100, and that the camera can be used well up to ISO 800. After that ISO level, the noise in the photographs can become too annoying. Even so, this makes the camera better for low light situations than I had previously thought. Note that I used ISO 800 for the image shown here, and it works very well. So changing ISO values has improved the camera's recording of subjects in low light situations.

Another exciting change has been using the Adobe Camera Raw program to convert the raw files to images. This program has made the processing of the raw files much better than using the Olympus Viewer 3 program. I can more easily control chromatic aberration, overall contrast, white balance, exposure levels, over-exposure recovery of colour information, and noise filters, etc. I am still exploring the program, but have been excited by the results so far. And because I still have the raw files of photographs taken with this camera from years ago, I can revisit many photographs and get improved images.

This month I'm presenting a small selection of photographs that I had been working on as part of experimenting with using Adobe Camera Raw, as well as some of the other experiments that have led to improvements in the accuracy of the colours in the photographs I've been taking. This display was originally presented in August 2016, and since that time, I have purchased a new digital camera (Sony A6000), and its results are better again than those presented here. With the Sony A6000 camera, I take all images as 'raw' images, and process these using either 'Adobe Camera Raw', or 'Capture One Pro for Sony'. I seem to be able to produce slightly better results using Adobe Camera Raw, but this does take more time and effort.

Note that I've coded some JavaScript tools for showing comparisons of images, so your browser might raise a response to ask whether you allow the use of JavaScript for these pages - please do.

 


Large wet leaves in a local garden



 

 
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