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Scan film and slides to print size
To scan film and slides to print size, start from the frame. A 35 mm frame is 24 x 36 mm, or 0.94 x 1.42 inches. At 4800 dpi it gives about 4,535 x 6,803 pixels, enough for 33 of our 34 listed sizes, up to 40 x 60 inches. At 2400 dpi it stops at 20 x 30.
Four film scans against 20 x 30 and 36 x 48 inches. Film area, not only dpi, sets the pixel count.
How big is each film frame?
A 120 film frame is 56 x 41.5 mm (6 x 4.5), 56 x 56 (6 x 6), 56 x 70 (6 x 7) or 56 x 84 mm (6 x 9). A 4 x 5 inch sheet is 4 x 5 inches by name. Medium format and 4 x 5 inch film start with much more film area than 35 mm. Scanners take film holders for 35 mm slides and strips, medium format strips up to 6 x 20 cm, and 4 x 5 inch film on one model, and 35 mm and 6 x 22 cm strips on another.
What is the largest print from each scan?
Each cell shows the scan's pixels and the largest listed size that meets 100 pixels per inch, with a crop allowed. Pixels are frame inches times dpi. One scanner goes up to 6400 x 9600 dpi and another lists 4800 and 6400 dpi. Those are scanner specifications and not a measure of film detail. We leave cells out above 4800 dpi for 120 film and above 2400 dpi for 4 x 5 inch film, where the scan is already far past our listed range.
| Film format | Frame (in) | 1200 dpi | 2400 dpi | 4800 dpi | 6400 dpi |
|---|---|---|---|---|---|
| 35 mm full frame (24 x 36 mm) | 0.94 x 1.42 in | 1,134 x 1,701: 10 x 12 in | 2,268 x 3,402: 20 x 30 in | 4,535 x 6,803: 40 x 60 in | 6,047 x 9,071: 48 x 60 in |
| 120 film 6 x 4.5 (56 x 41.5 mm) | 1.63 x 2.20 in | 1,961 x 2,646: 18 x 24 in | 3,921 x 5,291: 36 x 48 in | 7,843 x 10,583: 48 x 60 in | not shown |
| 120 film 6 x 6 (56 x 56 mm) | 2.20 x 2.20 in | 2,646 x 2,646: 24 x 24 in | 5,291 x 5,291: 36 x 48 in | 10,583 x 10,583: 48 x 60 in | not shown |
| 120 film 6 x 7 (56 x 70 mm) | 2.20 x 2.76 in | 2,646 x 3,307: 20 x 30 in | 5,291 x 6,614: 48 x 60 in | 10,583 x 13,228: 48 x 60 in | not shown |
| 120 film 6 x 9 (56 x 84 mm) | 2.20 x 3.31 in | 2,646 x 3,969: 24 x 36 in | 5,291 x 7,937: 48 x 60 in | 10,583 x 15,874: 48 x 60 in | not shown |
| 4 x 5 in sheet film | 4.00 x 5.00 in | 4,800 x 6,000: 48 x 60 in | 9,600 x 12,000: 48 x 60 in | not shown | not shown |
What does a worked example look like?
Take a 35 mm frame at 4800 dpi: (24 / 25.4) x 4800 = 4,535 and (36 / 25.4) x 4800 = 6,803 pixels. A 40 x 60 inch print needs 4,000 x 6,000, and both numbers are above that, so it fits. A 48 x 60 inch print needs 4,800 on the short side, and 4,535 falls below it.
What can the pixel count not tell you?
Film grain, focus and exposure limit what a scanner can record, so a 6400 dpi scan of a soft frame is a large soft file. The dpi is a hardware figure. Judge the scan at 100 percent before you commit to the largest size.
Find your scan's reach in largest print size for your photo's pixel size. Prints have their own page: scan old prints to print size. Phone, scan and video files to print size sits alongside, with more in our photo preparation guides, and image interpolation explains enlarging. For every size, see pixels needed for each print size.
What size print can I make from a 35 mm slide?
A 35 mm slide scanned at 4800 dpi gives about 4,535 x 6,803 pixels and reaches 40 x 60 inches at 100 pixels per inch. At 2400 dpi it gives 2,268 x 3,402 and reaches 20 x 30 inches. At 1200 dpi it reaches 10 x 12 inches. Judge the scan at full size first.