- D90 from Nikon
- Hh-Power 500mm/1000mm f/8 Manual Telephoto
- Nikon D90 - Ken Rockwell
- Nikon D90 Review Full Review - Video - The Imaging
D90 from Nikon
With the camera set to A, it's possibly on some body/lens combinations that it could affect shutter release (shutter mht not fire until lens has focus lock). I've edited the answer Based on the description from your lens, it appears your lens has what is known as FTM or full time manual focus.
Hh-Power 500mm/1000mm f/8 Manual Telephoto
I am bit confused how the auto focus and manual focus switching works, particularly with my gear.
Nikon D90 - Ken Rockwell
The confusing part is both the camera and lens have an A-M switch.
Nikon D90 Review Full Review - Video - The Imaging
Set the camera’s focus mode to AF-S, and press the shutter-release button halfway to initiate autofocus.
Nikon d90 manual lens:
Rating: 98 / 100
Overall: 99 Rates