How-To RTI Capturing
This page helps you getting started with capturing a set of images for generating RTI models with the Helios S53 .
For further instructions on how to operate the Helios S53, please download the full PDF manual .
Setting up the illumination device
- Place the object you want to photograph on a uniform and non-reflective surface.
- Ideally, place the Helios S53 over the center of the object such that the highest point of the objects surface is flush with the lower edge of the Helios S53. The distance from the the highest point of the objects surface to the lower edge of the Helios S53 should not exceed 10 cm.
- Attach the camera on top of the Helios S53 and connect it with the flash cable to the Helios S53.
- Connect the Helios S53 to the power outlet.
Camera Settings
- White Balance: If your camera offers to choose the color temperature directly select a color temperature of 5000K. If this option is not available choose the normal daylight presets.
- Image quality: RAW
- Exposure: We generally recommend ISO sensitivities of maximally 800 together with a shutter speed of 1/60 to 1/80 and an aperture of 11 to 14.
- Interval shooting: If your camera offers this option set the number of intervals to 48, the length of the interval to 1 second and choose one shot per interval. If you are using a capture software you might have to choose longer intervals to make sure the images can be transferred to your computer in time.
- Orientation sensor: If your camera has an orientation sensor switch it off. If it is not switched off some images might be rotated since the camera is placed horizontally on the Helios S53.
Aquisition
- Set the Helios S53 to "Sequence mode" by (repeatedly) pressing the button labeled with 'SEQ' until the button blinks in a green color.
- Make sure there are no other light sources lighting the object by checking your cameras live view. With only a small amount of ambient light you should still obtain reasonable results.
- You can now start the acquisition process by using your cameras interval shooting option or an image capture software of your choice. (In principle you can also trigger the camera 48 times by hand but this is not recommended since it might cause blurring of the images and slight changes of the camera position.)
- For each image another LED should be lit in the Helios S53.
Prepare Images for Authentica Creator
- Transfer the acquired RAW images from the camera to your computer.
- Open all images simultaneously in Photoshop or any other image processing program.
- Select all images and adjust the brightness and color temperature.
- Apply corrections for chromatic aberration and lens profile of your camera.
- Crop a rectangular selection which contains the object.
- Create a new folder and save the images as TIFF images using sRGB as color space.
- You can use a color depth of 16 or 8 Bit for the TIFF images.
- Make sure you only crop rectangular sections and don't rotate the RAW or TIFF images. You will have the possibility to cut non rectangular sections and apply rotation in Authentica Creator once the digital material is created.
Generate a RTI Material with Authentica Creator
Your images are ready now to be imported into Authentica Creator.
Please refer to the Authentica Creator User Manual to learn how to create a digital material (RTI model) from the images.
