SCANNING aka DIGITIZING SLIDES
How-To and F.A.Q.
The Primer: Scanning Slides with IT-8 Targets
In this article, I will explore a straightforward yet effective method for color-correcting scanned slides using IT-8 targets. My goal is to simplify the process: by using an IT-8 target to create a preset in Lightroom, you can achieve a 90% ready-to-show state for your scanned slides. This preset will help convert images taken with a digital camera and a light source to closely match the colors of the original film.
WHAT ARE IT-8 TARGETS?
An IT-8 target is a standard reference tool for color calibration of imaging devices. These targets include a series of color patches with known values, allowing for the creation of accurate color profiles. By scanning the IT-8 target and using color profiling software with the data provided by the target’s vendor, you can develop a color profile that consistently delivers accurate colors when imported into Lightroom or similar software.
WHY USE A SIMPLIFIED APPROACH?
Creating a full color profile from a transparent IT-8 target can be complex and specific to individual setups, which vary by light source, camera, and lens. Instead, I focus on a simpler procedure that anyone with an hour to spare and an IT-8 target can follow. This method is practical for improving the color accuracy of your digitized slides using commonly available tools and software.
Steps for Image Correction with IT-8 Targets
STEP 1: CALIBRATE AND PROFILE YOUR MONITOR
First and foremost, calibrate and profile your monitor. Without a properly calibrated monitor, all other steps will be waste of time. Accurate monitor calibration ensures that the colors you see are the best the device can provide
STEP 2: SCAN THE IT-8 TARGET
Place the IT-8 target in your scanning rig and capture an image using your digital camera and chosen light source. I recommend doing this at various exposure settings and keeping detailed notes on exposure (shutter speed, ISO, F-stop) and light source mode (Cool, Warm, White, or specific color temperature).
STEP 3: ADJUST IN LIGHTROOM
Import the IT-8 images into Lightroom. Try your best to fix every image of the IT-8 target. The initial look of the scanned image will not necessarily indicate the final quality after correction, especially if the target is "overexposed" by a couple of steps. In fact, an overexposed target can yield the best results as it effectively utilizes the full dynamic range of the sensor, which standard in-camera measuring techniques often neglect. Use the following tools in this order: Process Version (optional), Basic panel (White Balance, Highlights, Exposure, Shadows), and Calibration panel (Red Primary, Green Primary, Blue Primary). Ensure adjustments apply to the entire image and keep changes minimal. White balance should be based on the medium gray patches at the bottom of the IT-8 target (use patch 12). Once satisfied, save these adjustments as a Lightroom preset, unchecking settings you did not change or those affecting image geometry. Note the specific exposure conditions of the initial IT8 target capture.
STEP 4: APPLY THE PRESET
Use this preset to correct subsequent images captured with your digital camera and backing light source, ensuring that exposure and light settings match those used when creating the preset.
Practical Benefits and Further Reading
While this method may not achieve the precision of professional calibration tools, it provides a practical way to improve the color accuracy of digitized slides using commonly available tools and software. For more detailed guidance, a follow-up article will be provided.
The best source for IT-8 transparent targets is Wolf Faust. His site, http://www.targets.coloraid.de/, offers the “S2” kit, which includes everything a 35mm photographer might need. Note that I have no affiliation with this site and Wolf Faust.
Homemade Targets: An Alternative?
Creating your own target is possible but more challenging. You could use a Checker 24 target and, with the right skills, shoot it in diffused sunlight on fresh reversible film stock, processing it properly. Accurate exposure measurement with an incident light meter is crucial. However, the IT-8 target includes many colors not found on X-Rite ColorChecker or other popular targets like Datacolor SpyderCHECKR.
These additional colors are essential because some obscure hues might be off, requiring calibration tweaks. Typically, only the hue and saturation of RGB colors are adjusted in the calibration panel, but process settings can also be fine-tuned. Even slight changes can significantly impact color rendering.
Conclusion
I recommend IT-8 targets from Wolf Faust, priced around $80. They are affordable and save time while boosting confidence in your scanning workflow.
THE MOST IMPORTANT THING ABOUT DIGITIZING SLIDES? CASTING THE PERFECT LIGHT
Shown on the picture: The spectral distribution of CS-Lite in different modes. Warm works fine for slides, Cool is recommended for color negatives.
When scanning slides, the key is to get your lighting right. Natural sunlight works great for this, but it's available only half of the time ;-). A consistent alternative is an electronic flash or strobe light. If your setup allows the use of a flashlight, that's also a solid option.
Using an iPhone or iPad as a light source can be tempting, but the results are often unpredictable, so it's not recommended. For a more specialized setup, products like the Cinestill CS-Lite, with its 5000K setting designed for slides, or the VALOI Easy 35, or light from Negative Supply are good choices because they offer the right kind of light.
The important thing to look for in a light source is a high Color Rendering Index (CRI), ideally over 97. Cheaper video lights from places like Amazon might be tempting, but they can be hit or miss. Popular Kaiser Slimlite Plano light table is not particularly good either. This is because most LED lights are made up of diodes that might look fine to our eyes or a digital camera but don’t work well with the dyes in color films. This often results in colors like deep reds turning into mushy browns in your digital image.
Halogen lamps are another good option for quality lighting, but the heat they generate requires special consideration.
Overall, the quality of the light source makes or breaks the digital capture of slides, which are known for very saturated colors.
You can read my article at https://film4ever-digital.blogspot.com/2020/06/how-i-scan-transparencies-using.html where I go through my scanning setup step by step – mostly as a primer on technical implementation.
THE SECOND MOST IMPORTANT THING ABOUT DIGITIZING SLIDES: PROCESS THEM RAW
The second most important thing about slides is that they need to be digitized/scanned with a digital camera set to shoot in RAW format. Even with that, you may need to bracket the exposure because slides have notoriously high dynamic range - and that's why we love them so much. Using HDR processing is quite common when dealing with slides.
An important part of scanning slides is not to measure exposure for each frame. Instead, select a base exposure for a well-exposed slide so that the whites (say, the brightest clouds) come out as 99% white. Maintain this exposure throughout the batch to ensure properly exposed captures that reflect the brightness of the original slides. Research this topic further, as it is crucial know-how for digitizing/scanning slides.
Very simple setup based on Nikon slide copier ES1
Canon DSLR, Nikon ES1 Slide copy adapter, Canon flash. The rail is optional and is needed to keep adapter and camera aligned - otherwise adapter would freely rotates around lens axis. Changing slides require certain accuracy and aligning slide mount inside holder is responsibility of operator. That's why this setup make sense only if you scan no more than couple dozens slides at a time.
WHAT EQUIPMENT DO I NEED TO START DIGITIZING? CAN YOU ITEMIZE?
To start, you need a digital camera with a good macro lens, a film holder, and a light source. As you get more invested, you might consider a dedicated camera scanning rig. Here is some details:
Digital Camera: 24 MP or better DSLR or mirrorless camera is key for capturing pretty much every bit of useful info on the the 35 mm film negatives or slides. Both APS-C and full frame cameras will do. Pretty much any modern camera will do.
True Macro Lens: A true macro lens, one that provides a 1:1 magnification ratio, is crucial for focusing closely enough to fill the frame with a 35mm film frame. This kind of lens allows you to capture the most detail from your film. See more at https://www.film4ever.info/faq/lens#h.nlq6caa0vyl6
Light Source: You will need a uniform, bright light source to backlight your film negatives or slides. Among LED light panels RALENO are popular, but specialized light source like Cinestill CS-Lite or Negative Supply branded lights are certainly better.
Film Holder and Copy Stand: A setup to hold your film flat and steady is necessary. A film holder or carrier will keep the film flat, while a copy stand can hold your camera at the correct distance and angle, ensuring consistent framing and focus. See more at https://www.film4ever.info/gallery
Test Target: A test target, such as a resolution chart or a focus target, is not strictly necessary but highly recommended. It can help you align your setup and check for focus and sharpness, ensuring you get the best possible results. See more at https://www.film4ever.info/vtt
Software: Lastly, you'll need software to process the images you've captured. This includes inverting the negatives into positives and color correction for color negatives. There are several free software options available for this purpose. GIMP, a free and open-source image editor, has the capability to invert colors, as well as RawTherape or DigiKam . See more at https://www.film4ever.info/faq/software
This is a fundamental setup and should get you started with camera digitizing. As you progress and determine your specific needs and desired results, you may choose to upgrade or add to your equipment.
WHAT IS EASIER TO DIGITIZE - SLIDES OR NEGATIVES?
The slides (aka transparencies) are much more easier to digitize than negatives. When you capture slide image with a camera, you can see the result immediately and can make easy adjustments. When digitizing negatives, it takes from couple minutes to hours before you see the resulting image which should go through so called inversion process with photo editing software. Start your journey with digitizing slides - it will help you understand the process and tools better.
CAN I DIGITIZE SLIDES AND NEGATIVES MYSELF?
Absolutely! With some patience and the right equipment, you can turn your home into your own personal scanning lab. There is plenty inexpensive options now starting from Nikon ES1 adapter, to VALOI Easy 35, to Negative Supply and a lot of DIY solutions based on vintage slide duplicators from Nikon and Canon.
HOW DO I MAINTAIN THE QUALITY OF MY PHOTOGRAPHS WHILE DIGITIZING?
The key to maintaining quality is proper alignment, even lighting, and sharp focus. Good software helps, but being skilled in basic image correction helps a lot.
IS THERE ANY PREPARATION REQUIRED BEFORE SCANNING?
Yes, clean and carefully prepare your film to get the best possible scans. Use a soft brush or air blower to remove dust. Wear thin knitted cotton gloves. Handle your film by the edges to avoid fingerprints. It’s far easier to remove dust physically now than digitally later on! Use PEC12 and lint-free paper pads to remove fresh fingerprints or smudges. Never use any water-based cleaning solutions on film. Small scratches on base (shiny) side may be "healed" with nose grease (nasal sebum) - but be really careful with that.
HOW CAN I ENHANCE THE RESOLUTION OF DIGITIZED IMAGES?
The actual resolution (size in pixel) will be set once digital camera's trigger is pressed. The aim of all subsequent steps is to avoid deterioration of image quality. Generally speaking, use a good lens, ensure your film is flat during scanning, and digitize at the highest resolution your camera can handle. Post-processing software can further enhance the perception of the images, but not the resolution.
HOW CAN I PRESERVE THE ORIGINAL FEEL OF FILM IN MY DIGITIZED PHOTOS?
It's all about careful editing. Don't overdo it. Aim to preserve the original contrast, colors, and grain. The goal is to emulate the film, not erase it. Play with different film simulation modes in software (say in Nik plugins) to learn what makes "film look".