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11-11-2009, 07:04 PM   #1
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Basic flash help?


I have a Vivitar 285HV I'd like to use with my K20D. I've had this flash for a few years to use with my Spotmatic but I never actually used it.

I am using my K20D in manual mode because that is what I'm used to. I have read all kinds of stuff on how to use the external flash but I'm just not getting it. Can anyone point me in the direction of a basic tutorial on how to use a non dedicated flash?

Does the "calculator" on the flash determine what shutter speed and aperture you have to use based on the distance to the subject? What if I want to choose my shutter speed or aperture for creative reasons? I'm really confused. I know this is basic stuff but I need a little help understanding.



11-11-2009, 07:43 PM   #2
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Try this:

- Set the mode dial of the K20D to X. That will set the shutter speed to 1/180 sec.
- Match the ISO settings on the K20D and on the 285HV. For now, let's use 400.
- Set the mode dial of the 285HV to RED.
- Set the aperture setting on the K20D to the value point to by the mode dial of the 285HV. I don't have the 285HV here, but I think if you use ISO 400 and RED, the aperture is F/8.
- Focus and shoot.

That's the basic steps. Let's see how it goes.


- You don't have to set the mode dial of the K20D to X. You can leave it at M and choose any shutter speed equal to or lower than 1/180 sec.
- To use another aperture and still make use of the "auto flash" feature, turn the mode dial of the 285HV to one of the colors. Each color corresponds to an aperture value, use that aperture value on the K20D.
- For more flexibility, vary the ISO settings. But make sure the settings of the 285HV and of the K20D match.
11-12-2009, 10:02 AM   #3
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Thanks for the reply. I'll start with those settings & see what I get!

11-13-2009, 05:22 PM   #4
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QuoteOriginally posted by gsrokmix Quote
Thanks for the reply. I'll start with those settings & see what I get!

The Vivitar 285HV is a great flash to use in manual mode. Experiment with the color tabs on the mode dial of the flash. The calculator will help. Experiment with different ISOs. But always remember to use 1/180 or below or it won't fire. You may not be able to get 1/180 in Manual mode; more like 1/160. However you will ALWAYS be set to 1/180 in the X mode and all you have to do is change your aputere on the camera. The flash is great for bouncing as well.

11-13-2009, 09:29 PM   #5
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Read Lighting 101 and 102.
11-14-2009, 05:53 AM   #6
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You said you had your flash with your Spotmatic, so i figure it's an older unit. That being the case, I would check the trigger voltage to make sure it is safe on a digital camera. Just use a voltage meter set on DC and check the voltage between the side and center contact on the flash shoe while it is being fully charged. It should be below 30v., preferably below 10v. Anything higher could "fry" your camera's electronics.

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