EXPOSURE DETERMINATION
Using the TC-16 not only increases the effective focal length by 1.6X, but also decreases the effective aperture by a 1 -1 /3 f/stop.
Thus, when the TC-16 teleconverter is in use, you should disregard the prime lens's engraved aperture scale.
If the TC-16 is attached to lenses with a maximum aperture larger than f/1.8 (e.g., 50mm f/1.2, 50mm f/1,4, 35mm f/1.4, etc.), the effective aperture becomes f/2.9 even if the aperture is larger than f/1.8. Thus, when using fast lenses, be sure to set the aperture to f/1.8 or smaller; otherwise, incorrect exposure will result.
In addition, some exposure compensation will be required with lenses that have maximum apertures larger than f/1.8. For exposure compensation based on ASA/ISO film speed adjustment, refer to the fallowing table:
| Lens Max. Aperture | Compensation Required |
| (at ASA/ISO 100) |
| |
| f/1.2 | 2/3 f/stop underexposure |
| (set to ASA/ISO 160 position) |
| |
| f/1.4 | 1/3 f/stop underexposure |
| (set to ASA/ISO 125 position) |
| |
NOTES ON THE USE OF THE TC-16
1.The AF Teleconverter TC-16 cannot be used with any camera other than the Nikon F3AF with the DX-1 AF Finder attached. It provides only auto- focus—notfocus-aid—operation.
2.When you're not using the TC-16, set its ON/OFF switch to the "OFF" position; otherwise the batteries of the DX-1 which power the TC-16 may be drained.
3.During autofocus operation, hold the TC-16 properly because inadvertent touching of the focus lock button will prevent the teleconverter's lens elements from moving.
4.When it is cold, use the optional accessory Anti-Cold Battery Holder DB-4 to stabilize the DX-1 AF Finder's battery power; if the batteries powering the DX-1 are adversely affected by the low temperature, this will likewise affect the TC-16's autofocus response.
TIPS ON TELECONVERTER CARE
Always keep in mind that your TC-16 is a high-precision optical accessory and that rough, careless handling may damage it. Observe the following tips, and the TC-16 will always work as perfectly as the day you bought it.
•Keep clean and protect the surface of the electrical contacts ® of the TC-16 from dust and dirt; otherwise, electrical malfunction may occur.
