Slide Scanning Project 2014  (The Full Story)

This is a more detailed account of the slide scanning project I took on in 2014. I have a collection of over 8000 slides sitting in storage. The plan was to convert them into a digital format, maintaining original quality as well as cataloging each box of slides as they are converted. 

Time to Google

So I did some research on the net and found some interesting sites and videos on Youtube which by-passed the two standard ways of achieving the task; using either a flat-bed scanner or dedicated film/slide scanner. There are many cheap and expensive versions of these devices and all are quite slow at the scanning process. I purchased a Canon slide scanner (Canoscan FS 2710 non USB) years ago and have used it to successfully scan selected slides. It takes about 2 minutes per slide and only accepts one slide at a time. Not ideal for scanning 394 boxes of slides.

The research showed that there a quite a few people out there, like me, wishing to covert their slide collection into the digital form. With the advent of fully-featured, high resolution DSLR cameras, the idea of photographing the slides with a macro lens has become quite popular. Youtube Link.

There are even a recent commercial solutions that uses the same concept called SlideSnap Pro and SlideSnap Lite (US$2195) but are quite expensive, especially to purchase and ship to Australia. 

So with my backup Canon 5D MkII, 100mm macro lens and a $70 slide projector from eBay I set to the task of making my own scanning (photographing) system.

DIY Slide Scanner - A simple concept?

Like most home projects, it took some experimentation. First I removed the lens from the slide projector and also removed its 24V 150W halogen globe. It was just too bright and hot for illuminating the slides to photograph. I began by using my flash unit with the cover off the projector and reflected the light past the slide carrier and out through the lens hole. This gave an even, controlled (ETTL) light source with daylight qualities. It worked well but the arrangement with the cover off the projector and the flash mounted on top just did not look and feel safe or convenient. See below:


Looks technical but not practical! Using the Rollei P350A slide projector.

Next I found a 24V 20W halogen globe on the net and replaced the 150W globe and removed the large projecting lens inside the light compartment. Then added a white diffuser which I pinched from a cheap portable slide viewer (from eBay again).


 Original setup for with 150W lamp for projecting slides onto a large screen.

This now had the advantage of a smaller and cooler globe (although the cooling fan still operates). The cover then is replaced. You will also notice I have added 3 plastic pieces from a video light diffuser to scatter the light and produce a more even light source on the white diffuser behind the slide carrier.


Front view showing the white diffuser which is located about 8 mm behind the slide when inserted.

  For fine adjustment, the camera is mounted on a $20 Fotomate macro rail (eBay) on a baseboard.


For fine adjustment, the camera is mounted on a $20 Fotomate macro rail (eBay) on a baseboard.

   Aerial view with cover removed.   The Canon EF 100 f1:2.8 Macro will capture at 1:1 and therefore the image of the slide will match the sensor of the full frame Canon 5D.


Aerial view with cover removed.
The Canon EF 100 f1:2.8 Macro will capture at 1:1 and therefore the image of the slide will match the sensor of the full frame Canon 5D.

   The setup with remotes for operating the projector and camera. A much neater solution.   


The setup with remotes for operating the projector and camera. A much neater solution.
 

Colour Temperature

Probably the downside of using the lower wattage halogen globe is that it does not produce 'daylight' and does not illuminate the diffuser as evenly as the flash, with some minor vignetting occuring. However  I am willing to live with this and with a modern DSLR you can adjust the colour temperature to match the halogen lamp. I set it to 3300K and works well. The vignetting is relatively minor but can be seen when pointed out in a few images.

Manual Operation

There are ways to further automate the system so that the remotes are eliminated. However by the time you organise the slides and load them into the cartidge the time to manually shoot the images is minimal; 36 slides taking about between 1-2 minutes to photograph and save on the computer.

Other Issues: Exposure and Focus

Getting the correct exposure and focus is critical with macro work, so having the camera securely mounted and controlled by remote minimised camera movement and allows precise positioning of the lens. With the 20W lamp most slides can be taken on about 1/100 sec at f8 using 200 ISO. The depth of field being sufficient to set the focus using auto focus and then switching to manual. Using Aperture Priority mode, the camera adjusts the shutter speed for each slide to correct for exposure. I have found that setting the camera to under-expose slightly means the highlights don't blow out and the darker areas can be regained with post processing.

The Luxury of an Good DSLR

The Canon 5D provided so many solutions to the challenges in this project. Firstly a system to give 1:1 macro to match the size of the original slide film. A quality sensor to allow ISO 200 or higher for shooting with good depth of field and adustable colour temperature to match the halogen lamp. Remote switch and tether to a computer to monitor progress, label images and add metadata and keywords automatically. More on that later.

The next issue I noticed on a few images that they appeared to be suffering from camera shake, most likely as a result of the DSLR camera mirror movement. Its either vibrating the long macro lens or the slide itself in the slide carrier or both. So switching to mirror lockup and 'live view' mode, reducing the vibration and with the added avantage of displaying the slide to photographed on the screen on the back of the camera. Another problem solved :-) See samples below:
This had another advantage: if you move the small focus point around in live view mode, the camera will adjust focus based on the area around that point. A real advantage to ensure better exposure for each image as they are captured.

  Image from Kodachrome 1974 slide.


Image from Kodachrome 1974 slide.

   CLOSE UP SHOWING VIBRATION DURING CAPTURE WITH MIRROR MOVEMENT.


CLOSE UP SHOWING VIBRATION DURING CAPTURE WITH MIRROR MOVEMENT.

   CLOSE UP WITH MIRROR LOCKUP ENGAGED.


CLOSE UP WITH MIRROR LOCKUP ENGAGED.

Tethering - connecting the camera to the computer

One of the many advantages of digitising slide film is that it can be stored, organised and backed up on a computer system. Plus the fact that once they are on the computer, the images can be colour corrected, cropped etc and then used in the many ways such as printing, books, social media, websites, blogs, slide shows and on it goes. Using an iMac and Aperture for my photos, I took advantage of the tethering facility to monitor and organise the images as they are taken  and transferred to the computer. The images are placed in order from the slide box into the projector tray and their Box Number, Main Topics, Date and keywords as well as the individual Slide Number are automatically added to each image as it is taken loads into the Aperture software. Sharpening, colour correction etc can also be done on the fly if required. One big advantage of tethering is that each image comes up full screen as it comes into the computer. The system will do an automatic backup as well. All pretty cool. Fortunately I had recorded the keywords for each slide box years ago on a database, so these have been copied and pasted into the metadata for each slide as it stored on the computer. The nice thing is that this metadata goes along with each image. If one of these images is exported from Aperture and sent by email or USB stick the metadata or image information can be seen by applying a 'Get Info' command on a Mac or the equivalent on Windows.

JPEG or RAW?

Final decision. Do I photograph as JPEG or RAW? I tested both and knew RAW had the most advantages except for the file sizes. Aperture (via the Mac OS X) deals with RAW quite well, so RAW it is. Each RAW image is about 25 Mb so it might take about 250 Gb to digitise all the images, which is well within the capacity of a small external hard drive. There is quite an investment in time here, so if RAW offers the best quality at the time of scanning, then it makes sense to use it.
 

Sharing

I have been able to output the entire collection (8000+ images) at a medium resolution and burn them onto a single DVD for sharing with my family. I guess they might get some fun out of them one day. The full size of the RAW library is 240Gb which requires more serious storage options but a small external USB drive will cope quite easily for less than A$100.

 Samples

Laura in 1992 - Kodachrome Slide

  Original scan - no post processing. Slightly under exposed.


Original scan - no post processing. Slightly under exposed.

  Image CROPPED and adjusted for exposure.


Image CROPPED and adjusted for exposure.

  Sunset at Warrnambool 1976 - Kodachrome 64 (no dust removed)


Sunset at Warrnambool 1976 - Kodachrome 64 (no dust removed)


Terang 1976  -  Kodachrome 64  (taken with Pentax KX )

Since completing my collection I have successfully completed my parents slide collection from 1956-1987 (2640 slides). Quite a few hours too, but very rewarding.

 Peter on the right with Brother Rob and Sister Jen. Kodachrome slide 1956

Peter on the right with Brother Rob and Sister Jen. Kodachrome slide 1956

 

Cheers
Peter