Luminous Landscape Forum
Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: Andy M on May 09, 2008, 05:12:31 pm
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I've previously owned Canon's 85mm f1.2 mkII but sold it on due to frustrations with its minimum focussing distance, and it not suiting my wanting to take head and shoulder portraits.
I have a project coming up soon which I think the 85 would ideally be suited, but I will still need to get closer that the lens allows, and so I have been considering extension tubes.
By my calculations, if a 25mm extension tube was used the 85's minimum focussing distance would be reduced from 0.95m to approx 0.3 - is this correct?
Also, how will image quality be affected?
Finally, is there a specific extension tube people would recommend for portraiture work?
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The 85 1.2 does not nail focus on an extension tube. Focus will hunt and image quality deteriorates. There is a "glow" and details appear very soft. Use the 12mm, 25mm is overkill and you will not get the entire face in the frame. You will need to be too close to the subject. Kenko or Canon can be used, makes no difference. Overall there's no reason to do it, it looks like you've smeared vaseline on the lens. Further, if you have a model with a prominent nose, it will be supremely blurry and LARGE.
I've previously owned Canon's 85mm f1.2 mkII but sold it on due to frustrations with its minimum focussing distance, and it not suiting my wanting to take head and shoulder portraits.
I have a project coming up soon which I think the 85 would ideally be suited, but I will still need to get closer that the lens allows, and so I have been considering extension tubes.
By my calculations, if a 25mm extension tube was used the 85's minimum focussing distance would be reduced from 0.95m to approx 0.3 - is this correct?
Also, how will image quality be affected?
Finally, is there a specific extension tube people would recommend for portraiture work?
[a href=\"index.php?act=findpost&pid=194704\"][{POST_SNAPBACK}][/a]
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I use a Canon Close-up lens (500D) with my 85/1.2 - whether this will fulfill your requirements I'm not sure but it shouldn't be difficult to find out focus distances via a web search. Image quality remains excellent - although again its difficult to assess for your needs.
There are other suppliers - Marumi for example - who also produce good diopter lenses and I think that Zeiss do too - at a price. If you are serious this might be an option worth exploring.
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Super-fast lenses don't work well on extension tubes. You'll get some serious loss of contrast and sharpness, and then a lot of field curvature which will make things even worse at the frame's edges. Assuming the EF 85 mm 1:1.2 is extension-focused, with a 25 mm extension tube you'd be able to focus from 0.48 m to 0.41 m (or 1' 7" to 1' 4"). In order to start the working range where the lens without extension tube stops, you'd need a 9 mm extension tube (or a bit shorter than that when the lens has internal focusing).
Close-up lenses will work much better on the 85 mm lens. However you'd need a fairly weak close-up lens; the Canon 500D is too strong. With the 500D you'd be unable to focus at distances between 0.95 m and 0.65 m. For portraiture work you'd need a close-up lens with a strength of +1 to +1.25 dpt.
-- Olaf
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I've previously owned Canon's 85mm f1.2 mkII but sold it on due to frustrations with its minimum focussing distance, and it not suiting my wanting to take head and shoulder portraits.
I have a project coming up soon which I think the 85 would ideally be suited, but I will still need to get closer that the lens allows, and so I have been considering extension tubes.
By my calculations, if a 25mm extension tube was used the 85's minimum focussing distance would be reduced from 0.95m to approx 0.3 - is this correct?
Also, how will image quality be affected?
Finally, is there a specific extension tube people would recommend for portraiture work?
[a href=\"index.php?act=findpost&pid=194704\"][{POST_SNAPBACK}][/a]
Andy, instead of jury rigging it why not just use the 100 Macro, will get you close and is tack sharp!
One of my faves for portraits.
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Hi guys,
Thanks for the recommendations
I want the specific bokeh characteristics of the 85, which neither the 100 macro, or my 135L will give.
Are there any other options?
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Are there any other options?[a href=\"index.php?act=findpost&pid=195412\"][{POST_SNAPBACK}][/a]
Besides a short (7 - 9 mm) extension tube, a weak (+0.8 - +1.25 dpt) close-up lens, or using a different lens altogether, there are no other options short of simply using the 85 mm lens at 0.95 m and then cropping.
-- Olaf