What exactly is a fish eye lense?

[Spoon]

im planning to get the wal and the macro lenses from inon for my a95. i came across the fisheye lense by inon. is this like the wal but provides more coverage? is this a good thning and practical for the average photographer like me? also what is a dome port lense? so confusing. im also coming across terms like bayonet mount and screw on. pros and cons?

as of the moment i have been researching on a good add on lens for my a95. i am thinking of wetchangeable lenses, specifically the inon wal and macro lenses. i am also wondering what a good slotted tray would be that could accomodate the parking of the extra lenses and also have a handle and mount for the strobe. any tips would be greatly appreciated.

 

[PerroneFord]

It is a lense of very short focal length that tends to dramatically distort objects in the frame. Because of the design of the lens (lt resmebles the eye of a fish), at the extreme ranges, the lens is actually able to gather light from behind itself, so I can take more than a 180 angle of view. At the shortest focal lengths, it can be a challenge to even shoot the photo without gettnig yourself into the shot.

Be forewarned, the extreme nature of these lenses make them fragile and REALLY expensive. Think small car expensive for the shortest focal lengths. More moderate ones are in the upper hundreds.

 

[Spoon]

It is a lense of very short focal length that tends to dramatically distort objects in the frame. Because of the design of the lens (lt resmebles the eye of a fish), at the extreme ranges, the lens is actually able to gather light from behind itself, so I can take more than a 180 angle of view. At the shortest focal lengths, it can be a challenge to even shoot the photo without gettnig yourself into the shot.

Be forewarned, the extreme nature of these lenses make them fragile and REALLY expensive. Think small car expensive for the shortest focal lengths. More moderate ones are in the upper hundreds.

was just wondering thats all btw who uses these lenses? ive seen some photos wherein the oreintation is globelike, what are the applications of these shots for regular joes like us? i think il settle for the wal and macro lenses instead. thanks

 

[RonFrank]

It is a lense of very short focal length that tends to dramatically distort objects in the frame. Because of the design of the lens (lt resmebles the eye of a fish), at the extreme ranges, the lens is actually able to gather light from behind itself, so I can take more than a 180 angle of view. At the shortest focal lengths, it can be a challenge to even shoot the photo without gettnig yourself into the shot.

Be forewarned, the extreme nature of these lenses make them fragile and REALLY expensive. Think small car expensive for the shortest focal lengths. More moderate ones are in the upper hundreds.

Fisheye lenses do NOT distort the angle of view, they rather provide a 180 degree angle of view (no more). They are neither fragile (glass IS fragile, but ALL good lenses are made of glass), nor the cost of a car. They do NOT gather light from behind the lens (how would that even be possible?), NOR can one take a photo of oneself without paying attention. Nikons 10.5mm lens is under $600 which is on the low side of Nikon Glass.

The perceived distortion comes from an extremely wide ROUND view, and huge DOF. This is a view that our eyes can not capture. But this is NOT distortion, rather just vision beyond what we normally see.

From a technical standpoint there are two types of lenses, fisheye and rectilinear. Rectininear lenes basically capture a rectangle viewpoint. Fisheye lenses include a perspective that is beyond our view. With software available today, it's easy to take a fisheye lens, and create a Rectininear view, but croping will result.

If you are not aware of the applications, and do not own other lenses, the fisheye lens is NOT a good starting point.

Hope this helps,

L8R,

 

[PerroneFord]

In looking again, Ron Frank is right. In speaking, I forgot the march of technology. Though I am aquainted with new camera systems, it has been MANY years since I looked at fisheye lenses.

In ye olden days of Fisheye lenses, the glass optics would sometimes protrude beyond the metal barrel thus rendering the lense VERY fragile. In this orientation, it was indeed possible to capture images that could include the photographer behind the lens.

Reference The New 35mm Photographer's handbook 2nd revised edition, p20 for a photo of a Nikon 8mm f2.8 lens.

This is a pic of the 6mm: http://www.mir.com.my/rb/photography/hardwares/speciallenses/6mmfish.htm

This is the Sigma 8mm f4:
http://www.pcphotoreview.com/cat/digital-accessories/lenses/35mm-primes/sigma/PRD_84584_3111crx.aspx

The glass can be seen to slightly protrude, but it shows the march of technology.

I defer to Mr. Franks knowledge of distortion versus perspective, though I offer the quote from the 35mm photographers handbook p21:

"The wide angle of view and and circular frame can contain a complete horizontal plane when photographing directly upwared or downward. The extreme distortion limits their use and makes fisheyes unsuitable for most general photography."

[edit]

I wanted to add a quote from my Nikon f4 International Users Gude (copyright 1991)

p129, discussing the Nikkor 6mm F2.8

"Fisheye Nikkorrs reveal highly unusual perspectives with their extreme angle of view of 180 degrees or more, and also because of their equally extreme barrel distortion. "

"With this lens, you might even have problems keeping yourself out of the frame."


Now mind you, I was a journalistic photographer and moonlighted doing portraits and have never owned a fisheye lens. However, I do tend to put some stock in these very popular (for their time) reference books.

 

[RiotNrrd]

I shot a lot for a while, and had the pleasure of shooting some pretty wide angle lenses. Back to the original question of "what are they used for," generally they are used to capture extremely large things - typically architecture. A true fish-eye can give a neat look when you shoot something up close, but it's almost more like a special effect. Most of the times I have used them, I've been trying to shoot something like a building, and I've been far enough away that the distortion was minimized. But they are also good for indoor shots, like this, where you want to show a lot more than a "normal" lens can.

RiotNrrd