DPI defines an output grid
At 300 DPI a one-inch span becomes 300 pixels. Doubling DPI roughly quadruples pixel count for the same page area, which increases rendering memory and can increase output size substantially.
Start with the receiving system
Check accepted compression, bit depth, resolution and page arrangement. A valid TIFF is not necessarily valid for a particular filing system. Use a representative upload test before converting a large batch.
Inspect the source quality
Rasterizing vector text at higher DPI can retain sharp edges. Enlarging an already blurry scan cannot recreate missing strokes or characters.
Choose a setting with a measured example
At 300 DPI, an A4 page is approximately 2,480 by 3,508 pixels, or 8.7 megapixels. At 150 DPI it is approximately 1,240 by 1,754 pixels, roughly a quarter as many pixels. Start with one representative page and the resolution your receiving system requests; increasing DPI cannot restore detail absent from the original scan.
The workbench limits each rendered page to 20 megapixels and the complete job to 80 megapixels. Ten A4 pages at 300 DPI can exceed the total even when their source PDF is small. Select a smaller page range or lower resolution when that is acceptable. Oversized pages may need a lower DPI to stay within the per-page bound.
Open the downloaded TIFF in the actual application that will receive it and inspect its page count, pixel dimensions and resolution tags. Some image viewers display only the first TIFF frame; that is a viewer limitation rather than evidence that the remaining frames disappeared. Use a viewer that explicitly supports multi-page TIFF when checking a document.
For print workflows, physical page size depends on both pixel dimensions and the DPI metadata. A viewer that ignores resolution tags may show an unexpected default size. Compare its print settings with the intended paper size and make one proof print before submitting a long batch or assuming that a displayed zoom percentage represents physical scale.