How to Size Your Family Portrait Photographs
Have you ever wondered what size you should print your enlargements?
It depends on a number of factors such as;
– resolution of your camera
– which room in the house you want to hang the image (living room, bedroom etc)
– how far away you will be from the image
Did you know that the viewing distance of an enlargement is best determined by the resolution of the image and the diagonal width of the print? Billboards usually have a resolution as low as 22ppi (pixels per inch) because they are viewed from such a vast distance.
Some photographers use the formula of 1.5 to 2 times the diagonal width to determine the viewing distance.
I was pleased to deliver this image last week. Shot at one of my favourite Blue Mountains locations, this order was a 48” framed print of this family from Epping standing at Flat Rock, Wentworth Falls. At 48” x 25” and 300ppi it has a diagonal distance of 54” meaning it would be best viewed at 2-2.7m away.
Think of that next time you are buying a new 80” tv. You would need to have your lounge at least 4 meters away from the screen to see it correctly!
Another formula for the resolution of the image is 3438 divided by the viewing distance.
So, to view this image from 3m (120″) away, I would divide 3438 by 120 to find the minimum resolution of the print as 29ppi. This is obviously very low res but as long as I wasn’t standing inside 3m from the image it would appear to be quite sharp and detailed.
What this all means is that your small mega-pixel camera need not prevent you from creating big enlargements, as long as the minimum viewing distance is not exceeded they will look sharp and detailed.
I’m not sure how practical that is but its worth giving some thought to I reckon.
Here is a link to a good discussion on print resolution and viewing distance.