Images from scanners
Many reasonably priced desktop scanners can produce high quality scans which meet Alamy’s technical requirements. Follow these steps to get the best from your film images.
We ask that scans are sent to us uninterpolated at 48MB or above.
Shooting images on film
Images need to be of the highest possible technical quality. In general, shoot on the finest grain film, and with high quality lenses. Please note, however, that fine grain film is inherently high in contrast. Most desktop scanners cannot record the wide dynamic range of modern transparency film. If you are shooting images which are going to be scanned, try to keep the contrast down. However, do not go to the other extreme and shoot images with a ‘flat’ contrast.
Scanning prints
We do not recommend scanning prints as an alternative to scanning negatives or transparencies, scanning these will give superior results. If you are thinking of scanning prints then you must remember the quality of the original print is paramount - it must be sharp, with good colour saturation, and without excessive contrast. As with film, the scanner should be of the best quality possible. As a rough guide, a 10 x 8 inch print will need to be scanned at around 500ppi.
Film formats
35mm originals
To achieve a 70MB file from a full frame 35mm transparency, requires a scan resolution of approximately 4000ppi.
6 x 6cm and 5 x 4" originals
The larger the film area, the lower the scanning resolution needs to be to achieve a 70MB file. Medium format transparencies require a scan resolution of around 2000ppi, whilst a 5 x 4" original will need to be scanned at around 1000ppi.
Scanning images from film
- Choose a scanner with high quality optics, and a dynamic range (Dmin-Dmax) of at least 3.0.
- Do not scan above the maximum optical resolution of your scanner. Most scanners offer scanning settings way above their optical maximum. This is achieved by interpolation and results are usually unsatisfactory. Scan at the true optical resolution required to give a file size of at least 48MB at 8 bit. For 35mm, scanning a mounted transparency at 4000ppi will give a file size of around 50-55MB. Scanning an un-mounted transparency/negative at 4000ppi will give 65-70MB.
- We ask that scans are sent to us uninterpolated (at 48MB or above).
- Using your scanner software, set the black/white points at, or close to, 0/255.
- Ensure sharpening is turned off.
- Scan at the highest bit depth available, but convert to 8 bit before submission to Alamy. (Image>Mode>8 Bits/Channel)
- Difficult subjects may need a multi-pass scan to reduce scanning artefacts and capture maximum detail from the film.
- If using Digital ICE, we recommend the "Normal" setting. The "Fine" setting slightly softens the image. ICE can be problematical with Kodachrome film.
- If necessary, rotate the image so that it’s "the right way up".
- Open the scan at 100% and check that none of the film rebate is visible - if it is, crop cleanly to the edge of the image area.
- Carefully check the entire image at 100% for dust, dirt, scratches and other blemishes. These can be corrected using the Clone Tool, Healing Tool or the History Brush technique as appropriate.
Further help
- Achieving the best results:
- Images from digital cameras
- Images from scanners
- Improving image quality
- Retouching techniques
- The Alamy Forum - the answer may be there.
- Resources - photographer tips and a directory of scanning and keywording providers.