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Old Feb 12, 2010, 10:08 PM   #1
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Default Proper speed/exposure/shutter with a Fisheye

Hello,

I recently purchased a 8mm Fisheye (Rokinon/Falcon/Bower) lens for my Canon T1i, it's fully manual (aperture/focus).
I took some nice sharp pictures at night with f-stop @ 3.5 (lowest) and with the same f-stop in a shady interior space. Most pictures came out sharp.
But pictures I took outside were not good. First I forgot to set the f-stop and it was too low for the sunny conditions (and I wasn't looking at the pictures I took until afterward), and other than the pictures being really bright they were blurry. Is that from the excessive light or it that from not setting the focus properly?

My question is mainly about the MF usage: let's say I have a subject standing 1 meter away from me, I see no change when I look in the viewfinder as I turn the focus ring, although I think by the specifications of the focus I should see changes if the subject is between 0.3m-3m...
Well, the focal length is short, but still.
I just want to make sure: if the subject is more then 3m away, it's will always be focused with the lens? And then I can control the depth of field with the aperture?

Thank you
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Old Feb 13, 2010, 8:33 AM   #2
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Your 8mm lens has a depth of field such that, at f/3.5, if you focus 39 inches away, everything from about 19.4 inches to infinity will be in focus.

Your T1i has an M (Manual) exposure mode, that will help you with selection of your exposure settings, and you can also use the Av (Aperture Priority) Mode that should select an appropriate shutter speed whatever the settings you've selected for the lens.
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Old Feb 13, 2010, 10:15 AM   #3
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Thank you.

But when I took the pictures outside the subject had a very strong "haze", was that from excessive light?
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Old Feb 13, 2010, 10:38 AM   #4
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Can you post an example?
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Old Feb 13, 2010, 11:09 AM   #5
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Unfortunately I deleted the pictures after seeing they were unusable...
I have a photoshoot today so I might have an example of what I mean later.
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Old Feb 13, 2010, 11:56 AM   #6
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It was probably veiling flare causing the hazy look you saw. That's a common problem with some lenses (especially those without very good coatings, and especially ultra wide lenses with larger front elements), causing a washed out, hazy look to images when shooting in harsher lighting.

If it came with any kind of a lens hood, use it, and try not to shoot directly into brighter light (i.e., use the the old school way of shooting with the sun at your back when possible), shading the lens optics when practical to help reduce any flare related issues.
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Old Feb 14, 2010, 3:22 PM   #7
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Hi Jim, yes it appears to be exactly that, yesterday I had a shoot and I experienced some of the same things.
With direct sunlight it's really bad, the hood the is supplied is small because the lens has such a wide angle of view, but old-school and getting all the rest set-up properly I got some pretty sharp pictures.
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Old Feb 14, 2010, 4:39 PM   #8
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Quote:
Originally Posted by tphss View Post
Hi Jim, yes it appears to be exactly that, yesterday I had a shoot and I experienced some of the same things.
With direct sunlight it's really bad, the hood the is supplied is small because the lens has such a wide angle of view, but old-school and getting all the rest set-up properly I got some pretty sharp pictures.
Congratulations! Can you post some?
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