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chris.b
28th June 2010, 09:30 PM
Hi,

Can anyone please tell me of a cheap way that I can get a rectilinear wide angle lens of around 7, 8 or 9mm (14 - 18 in 35mm equivalent)? I don't mind using an adapter and manually focussing with aperture priority.

Many thanks in advance,

Chris

Ian
29th June 2010, 09:17 AM
Hi,

Can anyone please tell me of a cheap way that I can get a rectilinear wide angle lens of around 7, 8 or 9mm (14 - 18 in 35mm equivalent)? I don't mind using an adapter and manually focussing with aperture priority.

Many thanks in advance,

Chris

I guess you mean cheaper than a ZD 9-18mm? (around 469).

If you only need it for a limited period you can hire this or the 7-14 pro-quality alternative for 47 inc.VAT (not including shipping) for a week.

See: http://e-group.uk.net/hire/prices.pdf

Ian

Who's_E
29th June 2010, 09:22 AM
Chris,

What about going down the panorama route with a standard 14mm ZD lens and stitching them together. I haven't tried it for specifically widening a viewing angle but it could work and would be free.

I use Microsoft ICE for stitching (also free).

Nick

chris.b
29th June 2010, 10:43 AM
Thanks Ian and Mr E - both great ideas :)

snaarman
29th June 2010, 10:49 AM
Just a thought (and you might have to ask Nick Temple-Fry) but how rectilinear can one make the Peleng 8mm with photoshop, I wonder...

Pete

Ian
29th June 2010, 10:51 AM
The ZD 9-18 is under 22 for 7 days hire (not including shipping).

Ian

Nick Temple-Fry
29th June 2010, 11:36 AM
Just a thought (and you might have to ask Nick Temple-Fry) but how rectilinear can one make the Peleng 8mm with photoshop, I wonder...

Pete

Not sure I'd know the answer, the only suggested figure I can easily find for the Peleng is 175 fov diagonal uncorrected. But once you get into correction it is so dependant on what is towards the edges of the scene. If you compose with care then you can get away with no correction as in this image
(note that the sky has been crop'd)

http://e-group.uk.net/gallery/data/500/thumbs/P6042036_7_8_tonemapped.jpg (http://e-group.uk.net/gallery/showphoto.php?photo=24282).

But even if shot with a perfectly rectilinear lens then you would still have perspective distortion on anything towards the edges of the image, it would just be a slanted line rather than a curve. Personally, provided you keep the curve gentle, then I often prefer the effect from a FE.

Nick

Ian
30th June 2010, 01:23 PM
Inspired by comments here, I produced this guide to pano stitching here:

http://dpnow.com/7230.html

Ian

wanderer
30th June 2010, 03:49 PM
Hi Ian
Having read your guide I agree with virtually everything.
I generally use a lens of minimum focal length 50mm equivalent, longer if possible, to reduce parallax at the edge of each image. I also overlap by 30% minimum. Basically putting a figure on it.
I use Elements 7 software which is very good and very difficult to see the join.
I do have a Panosaurus which is useful for reducing foreground parallax but it is fiddly to set up in the field and I carry enough rubbish up the hills although the Tribrach head that came with it is handy for levelling.
Most useful item is a hot shoe bubble level as the bubble on my tripod is useless when in portrait mount.

I'm trying to remember what the OS used to use with their aerial photos, I think it was about 45% on line of flight and 20% between lines of flight.

I haven't as yet stitched 2 rows of pictures together but that may strain the capacity of Elements and my computer.

Duncan