Camera recommendations for photographing vintage posters for reproduction

[Munari]

I am considering a job to copy a client's vintage poster collection to be used for re-printing the actual size.  The original posters are approximately 41 inches high by 27 wide, some slightly smaller.  Please recommend the best procedure, and lens, and minimum Mega pixel camera to do so.

[kvbarkley]

A copy stand, A macro lens, a good even diffused lighting system, as many megapixels as you can afford.

[Munari]

These are too big for a copy stand, which I have tried.  Once I saw a photographer put a large poster on a wall and set his camera back a ways.  Must have worked, however I don't recall his camera and lens set-up.

[BurnUnit]

If you're wanting something that looks like a high quality photo up close you'd need a minimum of 45mp to make a 41 x 27 print at 200 DPI (8200px X 5400px). If the posters will be displayed at some distance you might get away with printing at 100 DPI (4100px X 2700px) which would be closer to minimum of 11 or 12mp, allowing for some degree of cropping.

Are you planning to print these yourself or have a commercial printer do the job? If working with a commercial print shop it would be best to consult with them directly to determine their requirements for the resolution and acceptable file types needed for their specific printing methods.

Someone else here will be better able to help you out in regards to specific lens, lighting suggestions and shooting methods.

[Waddizzle]

You need a large format scanner, not consumer camera.  A camera cannot capture an entire poster that size in a single shot without causing the text to look like hot dogs.

Let’s make some estimates of the resolution required to scan aa 41” X 27” document.  Let’s see what the numbers look like at 300 dpi.

27 inches x 300 dots/inch = 8100 dots (along the short edge)

41 inches x 300 dots/inch = 12,600 dots (along the long edge)

8100 x 12,600 = 102,060,000 dots or pixels.

102,060,000 , 1,000,000 = 102.06 mega-pixels.

You would need a camera capable of capturing at least 100 MP resolution to begin to capture an entire poster in a single image.  You would also require a large flat surface, and some type of camera stand above the flat surface to capture the images.

Or course, you could capture smaller pieces of the image with a lower resolution camera and stitch them together in post.  This would also require a large flat surface.  You would also need some type of adjustable camera stand, instead of a less expensive fixed one, so that you could position the camera over different parts of the large format document.

In either of the above scenarios, you will need some time of lighting system.  You would also need a robust computer and software to process the images.  A remote trigger on the camera will most likely be needed, too.

Let’s revisit the resolution.  A resolution of 300 dpi is probably the minimum that you would want to use to capture high resolution images.  You would want to scan at least at a 600 dpi resolution to avoid pixelation of small details and slanted lines.  

Scanning at 600 dpi would quadruple the size of your final image to 400 MP, which would need to be compressed to a JPG or some other compressed image format.

Or, you could spend those same few thousands dollars on a large format scanner, which are capable of resolutions up to 1200 dpi.