Closeup with Sigma 8mm fisheye

[richard_westlake]

<p>I've been using the Sigma 8mm f/4 circular fisheye for some time now and find myself wanting to focus more closely than I currently can. Does anyone have a reference to gear that would enable me to reduce the close focus distance without ending up focusing inside the lens? I have the three-piece Kenko extension tubes, but even the 12mm tube is too much. One thing I tried was adding an extra F-mount ring to the lens and holding it on the camera, but even that minimal extension is again too much. Is it possible to rig a small diopter to the rear of the lens for this job?<br>

Thanks for any assistance!</p>

[JDMvW]

<p>According to Sigma, the lens focuses to 13.5cm (5.3"). Just how close are you wanting to get??</p>

<p>I was curious so I put the shortest extension tube I had on my Spiratone 7mm. Here's the image I got with the front end of the lens actually touching the computer screen. Judging from the sharply focused dust specks, the sharp focus was somewhere inside of the lens, as you say. ;)</p><div></div>

[richard_westlake]

<p>Closer than 5.3 inches! :) Testing at f/22 or f/32 does a decent job of it thanks to the extra depth of field, but the exposure times get to be a bit much when it comes to foliage movement outdoors in the breeze.<br>

Realistically, I should just get a Canon 500D closeup filter and use it on my 12-24mm, but I love the curvature and extra angle of view the fisheye gives.</p>

[tommyinca]

<p>Nikon has a K1 ring which is only 5.8mm thick which in theory can do 1.3:1 fisheye macro, interesting. Before you try that, be aware of these.</p>

<p>#1 Some K1 ring will fit AF lens, some K1 will not. Either way, put it on slowly and in good light so you see what is going on and not damage the lens electrical contacts.</p>

<p>#2 Sigma 8mm EX fish is a G-Lens, so you will have no mean of controlling the aperture once you put on a manual K1 ring other then tape the lever to a preset value before you put the lens on.</p>

<p>#3 Watch the front element. With 5.8mm extension, the focus plane will be very very very close to the front element. Put it on a tripod and focus rail and watch what you doing from above and from view finder back and fore a few time. Note: If you put on too much extension (ie: 10mm), the focus plane will be inside the lens, meaning you will crash your front element. I didn't have a 8mm Sigma to try this out before hand.</p>

<p>BTW: Before you go buy a +2 500D. An 500mm focal length close up lens (what a 500D is), won't do much (a couple mm closer, may be?) on top of an 8mm lens. Also don't think the Sigma has filter tread up front as well.</p>

[tommyinca]

<p>16mm Fish with 12.5mm extension (full frame)</p><div></div>

[michael_bradtke]

<p>I have used a K1 ring with a 14mm AF lens.<br>

With my sigma 14 mm and the K1 ring the subject was touching the front element.</p>

[dcphotography]

<p><a href="../photodb/user?user_id=1841065">JDM von Weinberg</a> , what are the results if you stop all the way down with the 7mm fisheye with the extension tube attached? Will "infinity" be in focus?</p>

[mike_sanderson]

<p>This isn't Sigma...but its close....</p><div></div>

[JDMvW]

<p>Heck the Spiratone isn't all that sharp even without the extension tube when stopped down all the way.</p>

<p>I broke down all the connectors and adapters needed (M42 T adapter for the lens, then an M42 extension ring, then the M42>EOS adapter (yes, I'm a stinking Canonista, although also a Nikonian in pre-AI film cameras)) and put everything away, but I don't think it would bring things into focus even at the minimum f/45 on the Spiratone.</p>

<p>Mike, did your friend approve your posting that shot? Would be great lens for weddings, I'm guessing? ;)</p>

[richard_westlake]

<p>Don't worry, once you run that photo of the girl through PanoTools or Fisheye Hemi, she'll look just fine. ;)</p>