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08-07-2013, 12:25 PM   #1
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vivitar 2x macro focusing teleconverter

can someone please help ive just brought a vivitar 2x macro focusing teleconverter, i can only get it to focus at 1:3 with my 50mm M 1.7 attached to my K30, am i being a bit thick or have i got a duff one?

08-07-2013, 12:40 PM   #2
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you need to remember that for macro focusing is a function of subject distance also. you generally need to move the whole camera to get focused to 1:1
08-07-2013, 01:08 PM   #3
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You can download a copy of the manual from here:

Page 75

You need to extend the helicoid for macro function.
08-07-2013, 01:30 PM   #4
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ive looked at the manual and its of no use and ive also tried to focus on distance subjects at 1:1 and still nothing,

08-07-2013, 01:48 PM - 1 Like   #5
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QuoteOriginally posted by TGoode Quote
ive looked at the manual and its of no use and ive also tried to focus on distance subjects at 1:1 and still nothing,
With mine at 1:1 and my 50mm f1.4 mounted and at its minimum focusing distance, I need to be about 6 inches away from something to achieve focus. Start somewhere around there and move back and forth slowly until you get focused, don't mess with either focus ring. That is about the normal working distance for a 100mm 1:1 macro, which is what the lens becomes on this converter.
08-07-2013, 01:51 PM - 1 Like   #6
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Where you set the focus on the 50 will also affect it, but nevertheless you should be able to get 1:1. If the 50 is set at closest distance, it should focus at 5-6 inches away from front of lens, if the 50 is set at infinity it will be several inches farther away. But fairly close in any case. You won't be able to focus on anything very far away except with the converter at infinity (where it will act more like a regular 2x TC), it's a macro converter after all. So the more magnification you dial-in with the converter, the closer your maximum focus distance becomes, all the way down to just a few inches at 1:1...
08-07-2013, 02:20 PM - 2 Likes   #7
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Perhaps I am misunderstanding you. There are two scales on the Macro Focusing Teleconverter (MFTC). The blue scale is for when the 50mm lens is set to closest focus (0.45 m). The white scale is when the 50mm lens is set to infinity.

Are you saying the MFTC will not turn past the 1:3 marking either on the blue or white scale? If that is the case then the helicoid is damaged on the MFTC.

For macro function set the 50mm to either infinity or minimum distance (0.45) then set the magnification on the MFTC on the white or blue scale as noted above.

Example:
Set the 50mm to minimum focus (0.45m) and the focus ring on the MFTC to 1:1 on the blue scale. Move the lens closer or further away from the object until it is in focus. Magnification should be around 1x. Distance from the object to the lens should be around 133mm (0.13m).

The MFTC acts as an extension tube or bellows as well as a teleconverter and allows the lens to focus more closely than normal. The closer the focus the more the magnification.

If you are not getting ~1x magnification at the above settings then something must be wrong with the teleconverter. You can measure the magnification by photographing a ruler. At 1:1 the image should show about 23.7mm of the ruler across the long axis.

With the MFTC set to infinity your 50mm lens should focus from infinity down to 0.45m and the angle of view should be about the same as a 100mm lens. If not then something is wrong with the MFTC.
08-07-2013, 03:06 PM   #8
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thanks guys think ive got it

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