Slide Scanning Tips

Before you start to scan your slides first work out what equipment you will need to do the job. If you’re going to be scanning a lot of slides and you want the best results I would recommend a dedicated slide scanner, although you can scan slides and negatives on some flatbed scanners a specialised slide scanner will save you time and often give much better results.

Preparation

With a bit of preparation beforehand you can achieve a higher quality result, reducing any time spent rescanning or on photo editing software.

Homes can be dusty places and if you are scanning in an area with high levels of dust or other contaminants like pet hair it’s recommended you have a good clean up or preferably find an area that is clean and dust free. A great tip is to raise the humidity in the room as this will help reduce the dust in the air, a simple wet cloth over a radiator will really help.

Lighting is important and a good task light is essential to see what you’re doing and inspect the surface of the slides. Working on a bright, light coloured surface will also help when identifying the images within the slide.

Cleaning

The first thing to do is to check for any excess dust and build up on the slides or negatives, dust and slide contamination is likely to be the biggest threat to producing a crisp and clear digital image. Remember an essential tip is not to touch the slide surface as fingerprints can be tricky to wipe off and show up on the final scan. A pair of cotton gloves ensures no fingerprints.

Before you start scanning the idea is to get rid of the bulk of the dust on the slide with a dry, soft brush or a micro fiber lint free cloth. Make sure that brushes and cloths are static free and won’t leave tiny strands of the film. Once the bulk of any dirt has been removed give the slide a blast of compressed air. Cans of compressed air are perfect or if you have one, an air compressor would be more economical. Ensure the pressure is not too high, anything over 60 psi may be too much and loosen the slides in there mount so be careful not to over do it.

This should give great results for most dirty slides but if dirt still remains try using a photographic emulsion cleaner like PEC-12 or EDWAL Anti-Static Film Cleaner again applied with a lint free non static cloth. Remember it’s essential that you remove all loose dirt first, if you just use a solution on a dirty slide in a mount you end up just pushing the dirt into the edges. Try dabbing the area or using a small circular motion on the specific area.

Organisation

Being organized is important when conducting a large slide scanning job. And scanning the images in the order you want them to appear in your digital file is a good way to keep them well indexed. This allows you to organize the slides under the “date added” tag once on the computer which can be very helpful.

If scanning multiple sizes of film or slide mounts of differing thicknesses, try to group them together as this will reduce time spent changing settings on the device. If you can keep the images in the same orientation any post scanning rotation will be more efficient as it can be done in chunks rather than individually.

Storing your slides properly is important to reduce further damage from occurring and will also make organizing and finding them later a lot easier. Many different types of storage devises are available. Below are a few popular examples:

Plastic pocket sheets- A sheet of individual pockets that hold about 20 slides and can be stored in a standard ring binder folder, great for easily viewing slides and a cheap option.

Plastic storage boxes- A robust and easily available solution, good for holding about 50 slides and perfect for sending in the post. Make sure you have enough slides to fill the box as if they are empty slides often move around. See.  JRON company who supply the boxes

Card Archival boxes- An effective solution at a low cost, although less secure and more prone to damage over time. Find them for sale here at Preservation equipment

Large briefcase style-  these store approximately 250 slides in a briefcase style box can be a very neat storage solution, just remember to create index cards so you can locate particular slides easily.

Remember if you are conducting a large scanning job it will be a lot easier to store slides in a container in which you can grab a pile of slides at a time. Storage methods that hold individual slides in pockets can be very time consuming when taking out large numbers of slides.

Which ever method you choose remember to label the storage with a number or title, you really will be annoyed if you need to find one particular slide later and you haven’t labeled the boxes!

Scan settings

Each variety of scanners will come with its own software and will allow you to change different settings depending on the particular model used. Of course it depends of what sort of job you are doing and whether its quality or speed you are after. I find it can sometimes be best to turn off all the auto adjustments and concentrate on a high resolution and a high bit depth. This is because photo editing software is such a powerful tool that any colour changes or other adjustments can be done post scan very effectively. Of course on the scanners that have it, Digital ICE or other dust removal options are always worth turning on as those microscopic bits of dust can be time consuming to edit out afterwards. Remember to set the correct film settings in your software as Digital ICE will not work effectively with Kodachrome film or some old black & white films that contains metallic silver, check with your scanner beforehand to ensure compatibility. Note there are a few top end scanners that have versions of Digital ICE capable of using with Kodachrome slides.

Bit depth (or colour depth) is the measure of a scanners ability to record the tonal range of an image, the higher the bit depth the greater the range of tones that will be recorded. A colour depth of 24 bit will provide a good range for most uses and a scan at 48 bit would be considered very high.

Resolution describes the amount of detail that the image holds. Scanning at a higher resolution will mean a larger file size as the image will consist of more pixels. This is often indicated by the term SPI (Samples per inch) or DPI (Dots per inch; which is really more to do with printing resolution) Most standard slide scanners have an optical resolution of around 100-2400 SPI with the top scanners reaching resolutions of 4800 SPI or greater.

Playing with the settings and viewing the output files is quite often the best way of doing it, you’ve just got to find the settings that are right for achieving the results you want. So go on experiment!


File Formats

Setting the right output file is also important and again it all depends of what you will use the files for. Below is a general guide for my top 3 file types JPG, TIF and GIF

.JPG Probably the most widely used image format on the web and for digital photography. JPG’s are extremely compatible and perfect for use with photographic images. A key advantage is the format is easily compressed without much perceivable loss of quality (up to a certain extent of course). Perfect for web use, easy transferring, most printing requirements and file sharing.

Not the choice for Graphic images as JPG’s are not suited to blocks of single colour or defined edges, often leaving spears or patches.

.TIFF A TIFF file will give you a very high quality photographic or graphic image as it produces a file with almost no data loss. This means that the file sizes are bigger but TIFFs are perfect for using as lossless image storage. This means you can edit and resave the image without quality loss, whereas after a few save cycles a JPG will loose quality each time. It’s recommended to store a TIFF file as a master image file and convert copies to other formats for different uses.

The only downside of a TIFF is the file size, if you have the space they are probably the best quality photographic format.

.GIF A GIF file is perfect for storing graphic files that do not have many colors. If the file is under 256 colours then it can render with no data loss. If there are more colours then they will be guessed by the file’s algorithm, which may result is a massive loss of colour data. They are however a more space saving way of saving a graphic that in TIFF format.

Of course there are tons of other file extensions but these are the three I use the most, another two worth mentioning would be PNG files; another “lossless” format that works great for photos but with slightly less compatibility as a TIFF, and then there is the RAW format which is made up of the unprocessed data straight from the image sensor, these often have bad compatibility and require converting to other formats. In certain circumstances they can be useful as the raw file will contain all the information picked up by the scanner which may have been disregarded.

Post scan editing

Once your scanning is complete you may wish to enhance the images with photo editing software. Even with the best scan job you may still need to enhance the contrast, colour or retouch any scratches or blemishes.
Some scanners may come with simple editing software that can do minor adjustments but in my view, if you’re serious about your pictures and really want to get the best from them, then software like Photoshop or Fireworks is essential.

There is an abundance of online tutorials for Photoshop so I won’t detail the exact methods, just provide an overview of what alterations I would consider using. For detailed “how to” guides just search for “Photoshop tutorials” in your search engine.

These options are all under the Image> Adjustments heading in Photoshop

Levels Adjustment- This is the adjustment that will rectify an over or underexposed photo. By viewing the histogram of the image you can see if the tonal balance of the photo is too light or dark. Readjusting the darkest or lightest point by sliding a tab will bring the balance of the image to a prime position. The Curves tool will do a similar job but with more advanced options in terms of manipulating the tonal range. The levels adjustment is the first and often most effective alteration that I do, it really will make the image pop a lot more and add to the richness of the image.

Colour Balance- If the colouring in your image is not true you can manually correct it using the colour balance option. By sliding the marker towards a specific colour the hue will be shifted and with some tweaking the colour shift can be rectified.

Red Eye Removal- Found under the stamp button, this is a simple dropper tool that with one click on the red pixels in the eye will restore a natural look.

Clone Stamp tool- This is used to correct any blemishes on the photo. By cloning the area around the damage you can copy the nearby correct pixels to cover up the damage (do this with a soft brush setting and a reduced flow rate.)

At a more basic level changing the contrast and brightness of the image (also under the image heading) can be effective. A very quick option would be to use auto contast/bightness shortcuts on the keyboard. This will be a speedy way if you have a lot of slides to get through but obviously you will lose some control over the results. Auto options are also available for the levels and colour balance tools as well.

For more information on the features found on various scanners and how they work see my Slide Scanner Guide.