How digiscopers avoid vignetting
Vignetting worries many digiscopers who are just starting out. Their concerns are unfounded, as the SWAROVSKI OPTIK digiscoping experts explain. They provide tips on producing perfect digiscoping images without vignetting.
Vignetting is a dark shadow around the object being photographed which has one of the following causes:
The field of vision of the camera is larger than that of the spotting scope eyepiece and of the eye’s field of vision. This can happen when using the DCB II adapter and the TLS APO adapter from SWAROVSKI OPTIK.
Solution when using the DCB II: the black shadows can be removed using the optical zoom and/or by changing the camera position on the mounting rail. You simply zoom in until the object you want to photograph completely fills the frame or the display.
You are using a full-format camera (FX or 35-mm sensor sizes) with the TLS APO adapter from SWAROVSKI OPTIK. In this case the camera sensor is not completely filled with the image, which causes a black shadow to form.
Solution: you should switch to the correct camera mode (for example, in the case of the Nikon D800 to DX mode). If that is not possible, you can remove the vignetting during post-processing.
Basic tips for working with the DCB II adapter
Always stay within the optical zoom range, because the digital zoom will produce poorer quality pictures. It is best to test your camera together with the adapter at home to gain experience. This will help you when you are digiscoping out in the natural world.
Make sure that your camera is not crooked on the mounting rail. This can be caused by damage to the underside of the housing, dirt, and other similar problems.
The following products are particularly suitable for this type of application.