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Old Sep 5, 2007, 5:41 AM   #21
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Hi Pete,

This is how I use mine ... Fully manual ...the 50mm lens is set at infinity, and the viv converter to whatever degree of magnification you require, adjust focus by moving forward or backward as required ( you can also focus with the viv at whatever distance you decide on) with the onboard flash slightly diffused and set at -2.0EV, I use aperture f22 for greatest DOFon the 50mm lens, and set exposure to 1/180 or less for flash sync. you may need to juggle the flashexposure some. You should also find that you can get greater magnification by focussing the50mm less than infinity. Basicaly the viv gives 1:1 at max when 50mm is set at infinity. It also helps to use the focus trap technique.Hope this helps, feel free to ask further if needed. ... Jack
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Old Sep 5, 2007, 7:48 AM   #22
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Pete,

Just thought you may like to see my homebrew diffuser, it's nothing fancy, but does the job. I cut a piece of translucent material from a plastic bottle, and cut and folded it to wrap around the flash head, the black elastic thread that fastens it on was nicked from my wifes sewing basket, I believe it's called shirring elastic, other material could be used I suppose. Note the nicks in the plastic to locate the elastic. Pics should give you a good idea how it fits. I'm a great believer in use of flash with macro BTW ... it allows much smaller aperture to help DOF, and the short duration flash freezes movement, and combats any shake also. ... Jack.
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Old Sep 5, 2007, 7:48 AM   #23
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Pete,

Just thought you may like to see my homebrew diffuser, it's nothing fancy, but does the job. I cut a piece of translucent material from a plastic bottle, and cut and folded it to wrap around the flash head, the black elastic thread that fastens it on was nicked from my wifes sewing basket, I believe it's called shirring elastic, other material could be used I suppose. Note the nicks in the plastic to locate the elastic. Pics should give you a good idea how it fits. I'm a great believer in use of flash with macro BTW ... it allows much smaller aperture to help DOF, and the short duration flash freezes movement, and combats any shake also. ... Jack.
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Old Sep 5, 2007, 7:50 AM   #24
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Here it is on the camera ...
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Old Sep 5, 2007, 5:35 PM   #25
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Thanks Jack,
It all makes sense, except that with the converter in-place I can't control the aperture at all.

All the shots I take, when I preview them show that they were taken at f4.
But while shooting, I can't adjust the aperture.

Do you control the aperture on the 50mm lens itself?
Because mine is automatically controlled from the camera, then with the convertor there is presumably no electrical contact between lens and camera and so the camera cannot adjust the lens aperture.
The lens has no manual aperture, so would I need a different lens with a manual aperture control?

What I have done is use manual control on the camera then adjust the shutter speed until the little indicators show several bars of overexposure and then it comes out about right.

SO this shot hand held at 1/10th sec (so blurred) is eventually exposed about right.
To shoot at f22 (If I could ) would be about 10sec in daylight.
But your patented flash diffuser may help.
Cheers
Pete
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Old Sep 6, 2007, 5:01 AM   #26
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Pete,

You can't control the aperture through the converter, there are no electrical contacts on the converter sothe camera cant talk to the lens. You do need to use a 50mm where you can set aperture manually,that automatically stops downwhen you shoot ... the K mount should take care of that ( what are you using ?) set the camera to manual, and AF/MF switch to AF if you want focus trap ...set your aperture manually on the 50mm, and focus at infinity. Re. the flash ... the diffuser isn't absolutely necessary it just softens the flash effect. I've used the above with the Chinon 50/1.7. a Pentacon M42 50/1.8, and the Russian M42Industar- 61LZ-MC 50/2.8 ...the latter obviously loses out with light compared to the first 2, but using flash it's no problem. the latter 2 also need to be stopped down manually, so focus trap can become a bit iffy.All willgive excellent results in good light. ... Jack

PS. I'm not au fait with the K10D, so I'm not clear if it's use would affect the above in any way.

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Old Sep 6, 2007, 6:23 PM   #27
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I think I am getting the hang of this converter

I took this today in sunlight

I'll try flash tomorrow

Again thanks for help and advice

Pete
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Old Sep 7, 2007, 1:00 AM   #28
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petehemdig wrote:
Quote:
I think I am getting the hang of this converter

I took this today in sunlight

I'll try flash tomorrow

Again thanks for help and advice

Pete
Now That One is nice Pete!!

Dawg
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Old Sep 7, 2007, 9:35 AM   #29
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petehemdig wrote:
Quote:
I think I am getting the hang of this converter

I took this today in sunlight

I'll try flash tomorrow

Again thanks for help and advice

Pete
Looks like you're getting there Pete, that's much better, and you're welcome to the advice any time. I posted more shots using the Cosina 100mm f3.5 macro lens( Plastic Fantastic) they may be of interest, and I like to think, they show the capabilities of that particular lens. Link below... Jack

http://forums.steves-digicams.com/fo...amp;forum_id=7
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