The all-important LinkedIn Profile photograph. It's so easy to get right, but oh so easy to get it horribly wrong! Linkedin research has shown, "just having a picture makes your profile 14 times more likely to be viewed by others" and if this is the case, why not ensure it's the best photograph you can possibly have for a business networking site.
Adding a photo to your profile makes you 36 times more likely to receive messages on LinkedIn - Expanded Ramblings
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When it comes to choosing a photograph, you don't always have to go for a professional snap, but you can ensure you're on the right track by starting with a high resolution and friendly profile photograph.
LinkedIn profiles with professional headshots get 14 times more profile views - Expanded Ramblings
I've taken a look at some of my connections profile photographs which I think are great, either in greyscale or colour these photos are clear and concise.
Five of my connections
Five of my connections have their profile photograph spot on, using very clear and easy to view photographs with a mixture of colour and greyscale. Ruth and Luciano have used an image with a background but have been careful to ensure they are the center of the photograph, whereas Kat, Marsha and Peter have gone for a plain background. All these styles work well as they come across as friendly but still have that professional feel to them.