A viewfinder is essential to plein air painting. It helps you find a gem of a view in amongst the chaos of the outdoors. There are lots of good ones on the market but if you want a cheap answer you can make your own. To make a cheap viewfinder cut two angles of mat board the same size as in the photo. Outer dimensions 17cm x 14cm - inner dimensions 13cm x 10cm. This makes the standard ratio of the large image 4x6 which is common in framing. If you want to you can mark extra ratio's on the back of the viewfinder to give your favourite framing size if you like. I have marked 8x12 and 8x10 just to show what is possible. You can also hold it up to your paper and adjust to this size, then find your view. Options are limitless. Making the card mid tone and neutral helps make tone and colour decisions. Hope this helps!
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