Hi from Germany!
You can use Canon Extension Tubes II with EF Lenses and EF-S Lenses. And You can mount the Extension Tubes on full frame bodies. So why shouldn't I use a EF-S 10-22mm Lens on my full frame body?
Does it works? 10mm, non Fisheye???
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Hi from Germany!
You can use Canon Extension Tubes II with EF Lenses and EF-S Lenses. And You can mount the Extension Tubes on full frame bodies. So why shouldn't I use a EF-S 10-22mm Lens on my full frame body?
Does it works? 10mm, non Fisheye???
<p style="margin: 0in 0in 0pt;" class="MsoNormal"]<span style="font-size: 9pt; color: black; font-family: Verdana;"]This pertains to the EF-S 17-55mm f/2.8 IS specifically but the same would apply for the EF-S 10-22mm f/3.5-4.5 whenmounted on a full frame camera by way of extension tube(s).<span style="font-size: 10pt; font-family: 'Courier New'; mso-bidi-font-family: 'Times New Roman';"]<o:p></o:p>
See below:
[img]/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.26.13/EF_2D00_S-with-Extension-Tube.jpg[/img]
Thanks for such a quick response!
I didn't really believe that it could work - otherwise Canon would be able to create a 10mm non-fisheye Lens, and I am sure they would do it!
At a silent time, I will think about another exercise for You...[;)]
There is no point in that.
* Add an extension tube to any lens and it will not focus to infinity any more. Extension tubes are good only for macro work!
* I guess the image circle will not permit a EF-S lens to illuminate the corners of a full-frame at all and if with extreme vignetting only. Images might look like a circular fisheye, if you know what i mean.
* The magnification will increase so, you lens won't be 10 mm any more, because the focal plane will be further back.
* You might end up with, say, a 20-44mm lens that focuses from 0.3-0.5m. Usually Canon states these figures in the lens manual for both the 12 and 25mm extension tube. Try to find the manual and look those figures up, and you will know for sure.
* So yes, it will work physically, but it won't make sense. There is no such thing as a 10mm lens for full-frame.
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Originally Posted by sulla
True. I know a man who uses a EF-S 60mm Macro and extension tubes on his 5D Mk. II with no problems. He told me that there is also no vignetting with that combination.
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Originally Posted by sulla
There are circular fisheyes for FF as wide as 8mm.
I never thought of that. It sounds interesting.
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Originally Posted by sulla
Sure, you won't be able to focus on infinity. That's a drawback. But I wouldn't say there is no point.
Quote:
Originally Posted by sulla
Moving the focal plane does not change the focal length a priori (though, I'm told it does a little bit with some lens designs. I'd be very surprised if it changes from 10mm to something like 24mm, however.). Not only that, but assuming you focus at the same subject distance (there will be plenty of overlap of focal distance with a short extension tube), the distance to the focal plane will *not* be different with extension tubes.
The EF-S lens of course won't illuminate the whole of the larger ccd. But it will illuminate some of it :)
I agree to all the above arguments. I may have chosen my words sloppily.
As far as I understand it, it should be like this (I hope I'm not totally wrong, which I may be, I must admit):
The extension tube does not change the focal length of the lens, because this is fixed by the lens elements in the lens and an extension ring does not change that. But it does move the principal plane of the lens farther away from the focal plane (the sensor). This should have an effect on the angle of view: It should get more narrow, and thus the effect should be *like* en extension of focal length of the lens. Also, by this the image circle should increase (I believe) probably illuminating a full frame sensor.
I know the calculations are only true for focussing to infinity (i.e. parallel rays), but I calculate it like this:
focal length = distance of the principal plane of the lens from the sensor (for parallel rays), say zoomed to 10mm the principal plane would be 10mm away from the sensor.
Add a 12mm extension tube and this distance will be 22mm, so the "focal length" should be around 22mm - for focus to infinity, which, however, is not possible any more (this might be the catch of my over-the-thumb calculation), because the focus ring will be at its stop.
With my statement "there is no point in that" I ment that you will not have a setup that permits you to do landscape or indoor photography. I sort of assumed this was the principal purpose of an extreme wide angle lens.
Should I be totally wrong with my line-of-arguing, I'll take everything back and state the exact opposite!