I was thinking the other day about how I like the 5×7 ratio but do not really want to upgrade my kit to support 5×7. I rarely enlarge more than 11×14 anyway so I know I can crop and enlarge 4×5 to resemble 5×7. In the field it may come in handy to have a viewer that supports not only 4×5 but also 5×7, 4×10, 2×3, 3×4, 7×17 etc., all within the 4×5 film. When enlarging, I can cut a mask for the final print dimensions.

Using photoshop I created a 4×5 graphic with cross hatches at the 1/3rd and 1/2 points for establishing middle and rule of thirds composition, but then I added additional lines for other formats. I then printed this out at 4×5 inches on clear acetate (OHP) and mounted it in a 5×6 frame with the 4×5 cutout. I can use this to preview the scene before selecting a lens or establishing the tripod placement. If I see a 2×3 or 5×7 composition works better I can make sure to capture this on my ground glass using the viewer as a guide.

Having the crosshairs at midpoint or thirds point will also help strengthen composition and keep horizons level.

I have saved it here as a PDF which you can download and print yourself if you desire. Be sure you print it so that the frame lines are 4×5 inches with at least a 1/2 inch margin on all sides for attaching to your viewing frame.
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