Sunday, February 12, 2017

Non-TTL Adjustment: Vivitar 285 HV

 The Vivitar 285HV - Non-TTL Automation: The main reason that these older speedlights are relatively inexpensive is the "outdated technology" the use to automate exposure. When automatic flashes first appeared in the mid sixties, they offered the photographer the promise of properly exposed images within a range of distances. Instead of explaining how they worked, let's look at h how you might use the automation on a Vivitar 283-285 unit.

Composite #1: Color Coded Settings on the Sensor
Adjustment of the flash's output is controlled by a dial on the sensor. There are four color-coded settings (Composite #1):
  • Yellow: This setting will allow you to use the largest aperture within the sensor's range.
  • Red: This setting allows you to use an aperture two full F-stops smaller than the Yellow setting.
  • Blue: This setting allows you to use an aperture two full F-stops smaller than the  Red setting.
  • Purple: This setting allows you to use an aperture about one F-stop smaller than the Blue setting.
The 285/285 HV sensor dial has four manual settings: Full, one-half, one-quarter, and one-sixteenth.The Vivitar 283 sensor adjustments are very similar, but lacks the half, quarter, and sixteenth output settings.

Photo #1
This is the Calculator Dial of the 285HV (Photo #1). If you take a close look you'll see a white triangle which serves as an index mark for the ASA / ISO setting. The Calculator is currently set to ISO 200 (one click to the right of ISO 160).

If you look closely, you can see the four color-coded wedges matching the color patterns of the Sensor Dial. You can see the following suggested apertures:
  • Yellow: F 2.8
  • Red: F 5.6
  • Blue: F 11
  • Purple: F 16
With your camera set to ISO 200 and your Sensor set to Red, the dial suggests setting your lens aperture to F 5.6. So long as the sensor is looking directly at your primary subject, the flash will meter out enough light to properly expose you subject, based on the amount of light that is reflected back.

The final step to set the lens aperture based on the sensor's color code. A little complicated, but this type of non-TTL metering will work on any camera's hotshoe.

Photo #2
The ISO can be changed by rotating the Sensor Dial to 400, the circular scale advances to indicate values that are one F-Stop value smaller that those for ISO 200, just as you might expect (Photo #2). Again, a simple design that is reliable, but subject to the variables of sensor alignment.

I must give credit to the engineers who designed the basic Vivitar flash platform. A number of features border on genius. For example, the sensor eye can be removed and one end of the extension cable inserted into the flash body. The camera end of the cable is mounted in the camera's hot shoe, and the sensor inserted. You can see in Photo #3 that the cable, attached to the hot shoe, keeps everything properly aligned.

Photo #3: Extension Cable Installed
Photo #4
To add to the versatility of the extension cable, there is a small contact at the base (camera end) that allows one to install a Wein Peanut Slave (Photo #4), if the situation forces you to regulate the flash output manually.

This might not seem like a big deal, it means that you can completely enclose a 285 HV within a softbox. You can control, and trigger the flash from outside the softbox with a Peanut Slave

One last feature is the 4AA cell battery holder. You can keep extras pre-loaded with fresh batteries available for a quick battery change Also, if there's a battery leak, the insert, rather than the actual flash contacts, takes the corrosive "hit".

Pretty nifty, Little Vivitar 285!