SVBONY have released a replacement nosepiece with filter threads for the SV105 low cost astronomy camera. This is one of the suggestions that I made to the company about this low cost, well built, USB astronomy camera. The camera is too sensitive to use with a fast scope on a bright object such as the Moon. If an extender tube was used to attach a neutral density filter, it became impossible to bring the camera to focus on some scopes due to lack of back focus. This simple solution allows a ND filter to be attached directly to the nosepiece, so that focus can be achieved.
Replacement nosepiece
The old nosepiece simply unscrews without disturbing the IR cut filter, and the replacement nosepiece screws into place. There is thus, no danger of introducing dirt onto the sensor during the process.
Replacement nosepiece in place
The filter threads can be seen.
A Double polarising filter is attached to the nosepiece in this instance, to allow exactly the right attenuation to be achieved for optimal exposure and frame rate.
The SV105 with a double polarising filter attached.
This is a significant improvement to the camera.
It should be remembered that for best results, flat fields should be employed to correct for pixel vignetting.
