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Old Dec 5, 2011, 10:07 AM   #1
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Default NEX5 and Samyang 7.5mm

Today arrived my (MFT) Samyang 7.5mm - my 5th Samyang
It's for my LUMIXes, but also for NEX5 (and NEX7, hehe). Samyang 8mm (constructed for APS-C) isn't vignetting,
7.5mm (for m4/3) only a littlelittle bit, but you can see (special left/right) parts of lens hood.
Either you cut photo ... oooor you cut lens hood.








Some pictures with NEX5 und Samyang 7.5 - there is no fisheye effect, but a ROUND table! Aperture f=3.5 ... f=22
Distance of nearest ball = 1 cm from lens, distance on lens = 9cm.
Diameters of balls ca 10mm.










Last edited by DonalDuc; Dec 6, 2011 at 7:15 AM.
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Old Dec 5, 2011, 2:07 PM   #2
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G3 with Samyang 7.5mm
NEX5 with Samyang 8mm

Both no vignetting, very sharp .. both "low price"




Last edited by DonalDuc; Dec 5, 2011 at 6:04 PM.
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Old Dec 6, 2011, 8:39 PM   #3
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If you want to use this with the NEX, you'll have to remove the shims behind the mounting plate, and shave the lens hood. Here are some instructions

How to Modify the Lens
To use the Samyang 7.5mm MFT fisheye lens with a Sony NEX camera you will need to shave the lens hood, remove shims, and attach a MFT to Sony E-mount adapter.
Shave the Lens Hood
Remove the black metallic label ring to reveal three screws which attach the hood to the lens. The ring is backed with adhesive tape, pry gently. Remove the three screws and detach the hood. You need to completely remove the short shades of the lens hood, and shave about 3mm off the top and 1.5mm off the sides of the large shades. Draw a line along the intended cuts, clamp ($3) the hood, and use a hack saw ($4) to cut a little bit less than intended. Use a nail file ($1) to remove the rest. You should check intermittently with your camera to see if you have shaved enough of the hood so that you no longer see it in the image, making sure to clean off the dust every time before reattaching.
Remove Shims
Unscrew and detach the mounting plate on the back of the lens. Inside you will find multiple adjustment shims which vary for each lens. Mine has one brass shim 0.3mm thick and one metallic shim 0.06mm thick. You may find more in your lens. Remove as many as required to achieve focus to infinity. I found that removing both shims worked best for me. Best focus was between f11 and f8, with f11 sharper at the edges and f8 sharper in the center. I found f22-f11 too soft in the center and f8-3.5 too soft at the edges. Best focus with shims removed was just a bit below the infinity mark.
MFT to Sony E-mount Adapter
You need an adapter to attach the MFT lens to the Sony NEX. The adapters from ebay seem to be machined slightly wider than necessary and the lens sits loosely inside the adapter. To make a tighter fit insert the end of a screw driver into the slot inside the adapter mounting teeth to widen it. Do it slowly and in increments, checking constantly if you are getting just enough tightness. It is possible to make it too tight and then you'll have to press them back down. You can also drill holes into the adapter and screw it directly onto the lens mount, but you would have to unscrew the adapter if you want to remove the lens from the panohead. I eventually did this because the pin on the adapter wore out and the lens frequently unintentionally detached itself from the camera.
I use this setup for spherical panoramic photos
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Old Dec 6, 2011, 8:45 PM   #4
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sorry double post

Last edited by thomash2; Dec 6, 2011 at 9:30 PM.
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Old Dec 7, 2011, 6:14 AM   #5
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Hmmm ... removing hood = solution ?

How to remove this ring? Is it only glued?




Vignetting - look http://forums.steves-digicams.com/pa...-lumix-g3.html

Last edited by DonalDuc; Dec 7, 2011 at 6:27 AM.
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Old Dec 7, 2011, 1:30 PM   #6
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You can easy remove front ring and unscrew hood.

Diagonal angle for m4/3 is 180 - for NEX5 (APS-C) it is more than 180
Pictures are similar like with Peleng 8mm









Last edited by DonalDuc; Dec 7, 2011 at 1:37 PM.
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