Ad
Ad
Ad
Pages: [1]   Bottom of Page
Print
Author Topic: Should I get a fish eye  (Read 3378 times)
sanfairyanne
Full Member
***
Offline Offline

Posts: 233


« on: September 14, 2012, 03:20:23 PM »
ReplyReply

I just did my very first spherical panorama today with PTGui then put it into a program called KRPano and I'm really happy with the results. I can see myself doing more of this type of thing but I wonder if I should get a fish eye as several You Tube tutorials show people using them.

In the tutorials I see people getting a full 360 degree panorama in 4 shots a full spherical takes 7. I just did my pano today with a 16-35mm lens but I needed 8 shots to get 360 degrees and to make a big overlap I shot three rows plus the Zenith and Nadir shots making a total of 26.

I have a full frame sensor, so if I bought say the Canon 8-15mm zoom I would have to set it at 15mm.

I have to wonder how can this extra 1mm make so much difference ?

Logged
k bennett
Sr. Member
****
Offline Offline

Posts: 1417


WWW
« Reply #1 on: September 14, 2012, 05:14:35 PM »
ReplyReply

It really is amazing how much difference in angle of view there is between a 15mm fish and a 16mm rectilinear lens. I rarely have to worry about getting my feet in the frame with my 16-35, even held vertically, but with the fish this is a common problem.

I can't comment about the fisheye's usefulness in pano photography as I have not tried it, but now I think I shall have to do so.

You could buy the Canon 15mm fisheye on the used market so that you can re-sell it without much loss should you not like it, or want to trade up to the new model.
Logged

Equipment: a camera and some lenses.
BartvanderWolf
Sr. Member
****
Offline Offline

Posts: 3440


« Reply #2 on: September 14, 2012, 06:16:09 PM »
ReplyReply

I just did my very first spherical panorama today with PTGui then put it into a program called KRPano and I'm really happy with the results. I can see myself doing more of this type of thing but I wonder if I should get a fish eye as several You Tube tutorials show people using them.

In the tutorials I see people getting a full 360 degree panorama in 4 shots a full spherical takes 7. I just did my pano today with a 16-35mm lens but I needed 8 shots to get 360 degrees and to make a big overlap I shot three rows plus the Zenith and Nadir shots making a total of 26.

I have a full frame sensor, so if I bought say the Canon 8-15mm zoom I would have to set it at 15mm.

I have to wonder how can this extra 1mm make so much difference ?

Hi,

It's not just the focal length, but more due to the different projection (rectilinear versus fisheye) that does the trick.

The EF 8-15mm lens is super, but the 15mm is no slouch either. If money is not an issue, I'd get the 8-15 in a heartbeat, it's very sharp all the way up to the edges. It's coating is quite good which is important because it's hard to keep lightsources/the sun out of the image. The only drawback is that manual focusing (for hyperfocal DOF) is tricky because of the short focusring throw angle.

When you need to minimize the number of shots, e.g. for speed of shooting a 360 VR panorama in an awkward spot or with lots of movement, it can be done with a 15mm fisheye in 5 shots (+ one for the nadir if the ground detail cannot be reconstructed). You'd shoot 4 shots aiming down 20 degrees below horizontal, and one straight up for the zenith. So in a maximum of 5-6 shots you can move to the next spot.

When shooting in contrasty lighting conditions is is not too much of a burden to add exposure brackets.

Cheers,
Bart
Logged
sanfairyanne
Full Member
***
Offline Offline

Posts: 233


« Reply #3 on: September 14, 2012, 07:04:44 PM »
ReplyReply

I did have a look at it just recently my local dealer even offered to lend me one. I was utterly amazed how poor the lens cap is. I mean it just won't stay on, it would be utterly foolish to put this lens in a gadget bag without some sort of wide elasticated strap holding the cap on. In fact it comes in the box with a piece of tissue between the body of the lens and the actual cap which in a way helps to squeeze the cap on. For a $300 lens this would be inexcusable but for a significantly more expensive L lens it's just unbelievable.

I don't want to borrow the lens just in case I damage it but I'll certainly go back to the store and test it out.
Logged
k bennett
Sr. Member
****
Offline Offline

Posts: 1417


WWW
« Reply #4 on: September 14, 2012, 10:13:35 PM »
ReplyReply

I have a piece of gaffer's tape holding on the lens cap on my 15mm fish. Gaffer's tape is wonderful stuff.
Logged

Equipment: a camera and some lenses.
Ellis Vener
Sr. Member
****
Offline Offline

Posts: 1726



WWW
« Reply #5 on: September 18, 2012, 08:42:03 AM »
ReplyReply

If you are looking to speed up the stitching process and don't need a large resolution ( H x W in pixels) file that shooting with a rectilinear lens and stitching produces,  the Canon EF 8-15mm f/L is a good choice. At 15mm on a full frame (24-36mm Canon sensor the lens is a full frame fisheye - which means that the diagonal across the frame covers approximately  180 degrees. Set it to 8mm and you get full 180 degree coverage in all directions - i.e. a circular image. See the attached for a comparison to the two angles.

Shooting with a rectilinear lens has its advantages:
- greater resolution  whether you are counting pixels or lookign at detail ( the narrower angle the original view captures the more pixels real world detail covers)
- more cropping possibilites
- more spatial rendering possibilities.

But if you are just shooting to create immersive 360 views to be viewed on screen a fisheye should work well for you.

(if you are wondering why you don't see either my feet and only a small section of the tripod leg in the 8mm view  it is because  the camera was mounted in a PCL-1 clamp on the end of a Really Right Stuff CB-18 camera bar mounted to the head of the tripod - effectively putting all of the mounting hardware (Tripod, tripod head, camera bar, PCL-1 clamp, and sandbag on the tripod) behind the camera.)
« Last Edit: September 18, 2012, 09:07:46 AM by Ellis Vener » Logged

Ellis Vener
http://www.ellisvener.com
Creating photographs for advertising, corporate and industrial clients since 1984.
joneil
Full Member
***
Offline Offline

Posts: 127


« Reply #6 on: September 18, 2012, 03:09:39 PM »
ReplyReply

  See if you can rent one for a day and go shooting with just that lens, anything and everything you can.  Then look your shots over on your computer, and you will likely know right away.   fisheye lenses are very specialized, and I find that most, not all, but most people either love or hate them almost right away.

  The other thing is the fisheye may not be the lens for the job you are looking for, but you might like it all just the same

good luck
joe

Logged
sanfairyanne
Full Member
***
Offline Offline

Posts: 233


« Reply #7 on: September 18, 2012, 03:29:49 PM »
ReplyReply

Thanks guys,

I did actually get to borrow the 8-15 canon for a few days to use on my 5d2 and did a 360/180 VR pano tour of a beautiful old building in Liverpool England. I can see many benefits of using a fisheye, less images mean there's less processing to do to remove people in the final image. I understand it's also possible to take most of the pano with say a 24mm lens but fill in the floor with a fisheye.

I have two or three landscape shots I'd like to try with a fisheye, plus some of Utah/Arizona's slot canyons could have cool potential with a fisheye.

The Canon Zoom is a bit expensive for me, actually I was surprised how much CA there was for a lens of this cost, I know how to take it out in post but really didn't think it would be so evident in the image.

As always there's a lot to learn, thanks for the replies.
Logged
Ellis Vener
Sr. Member
****
Offline Offline

Posts: 1726



WWW
« Reply #8 on: September 20, 2012, 10:30:34 AM »
ReplyReply

Chromatic abberations seem to be inherent with all fisheyes lenses.
Logged

Ellis Vener
http://www.ellisvener.com
Creating photographs for advertising, corporate and industrial clients since 1984.
kers
Sr. Member
****
Offline Offline

Posts: 720


WWW
« Reply #9 on: September 20, 2012, 06:50:11 PM »
ReplyReply

...The Canon Zoom is a bit expensive for me, actually I was surprised how much CA there was for a lens of this cost, I know how to take it out in post but really didn't think it would be so evident in the image. ....

I have the nikkor dx fisheye 10mm about since my first dig camera - a fuji S2. With all the cameras after that the quality got better...
It is not only the lens but also the sensor and the angle of the rays hitting the sensor that determines the result.
Logged

Pieter Kers
www.beeld.nu
Pages: [1]   Top of Page
Print
Jump to:  

Ad
Ad
Ad