Good Lens for Pano work

[campdog]

Hi, Ive been having a bit of trouble with getting good sharp panos.Still trying to work out current problems but Im off to the US in May and want to capture a lot of 180 + degree panos. I have a sigma 10-20 but not happy when stiched together.I also used a fa* 28-70mm f/2.8 @ 29mm but a lot of shots to ger what I wasnt.
Would anyone be able to reccomend a wide angle or fisheye for my Pentax K5. I think the less shot joined safer and better.Its not a trip that I would be able to go back and reshoot.


John

[DennisS]

Anyone who has seen my work knows that I use a monopod for vacation panoramas. I use a Sigma 8mm f3.5 lens, NN Ultimate R1 at 5 degrees, a monopod and bubble level. 4 around plus a hand held Zenith shot is all that is needed. This very portable rig has allowed me to take panoramas where I would otherwise not have been able to. Practice is the key to good results. I know that just about everyone else has seen this link and the panoramas many times, but they are good examples of what is possible with the Sigma 8mm lens: http://www.dlsphoto.net/Europe2009/Europe2009.htm

[campdog]

Thanks Dennis. Los Angeles is my first Stop off.
John

[campdog]

Very Inspiring work Dennis. Im not sure if thats the type of panos I want to do. Im looking for a wide shot ets say 180 degree for hanging on the wall. Wouls I get that with a 8mm lens or too much distortion.
John

[John Houghton]

Fisheye "distortion" gets corrected in the stitching process and does not make its presence felt in the final panorama. Essentially, the panorama will look the same regardless of the lens used. The image quality and resolution will vary with the lens, of course. Generally, using longer focal length lenses will need more shots to be taken to cover a given angle of view but will deliver more pixels and therefore tend to give better overall quality.

John

[DennisS]

When I am creating a thumbnail of a panorama, I take the final panorama and crop away the bits I do not want. It is easy to chop off the top and bottom of a 360x180 panorama and end up with very nice "flat" panorama. Here is an example of a complete sphere with only the top and bottom removed:



Before I started trying spherical panoramas, I did cylindrical panoramas with a Nikon Coolpix 880 and a wide angle adapter. The results were very nice. An 8mm lens may be too much distortion. What is it about the Sigma 10-20mm lens that you are not happy with? I did a couple of test spherical panoramas with that lens and were happy with the results. How are you stitching? PTGui handles partial cylindrical panoramas very well.

[Hugh]

Hello John,
I would also like to know why you are not happy with the Sigma 10-20mm lens as, in theory, it should be ideal for panoramic photography as it has a single point for the Entrance Pupil so that if it is rotated about this point all the rays in the images radiate from the same point.
http://www.hugha.co.uk/NodalPoint/Index.htm#Results_

[campdog]

Hi Dennis. I have been finding a out of my pano shots were not sharp in places, especially in the background. I thought it was me or the lenses I was using. I have been following the Forums on the Pentax K5 and a lot of people were having trouble with front focusing in low light,Pentax just released a firmware upgrade to try and rectify the problem. I installed the upgrade as well. I decided to run a test yesterday afternoon comparing my K10D any my new K5. I manually spot focused on a spot in my garden @ 10mm on the sigma (manual mode). I used aperture f/11 and started at ISO 100 and increased until the K10 ran out of puff at ISO 2000. I keept the aperture at F/11 and adjusted the shutter speed ot get a correct exposure.I used white balance in (shade).
Comparing the shots it was easy to see the K5 was much better focus in the foreground but when comparing side by side the K10 was better in the background and the K5 was out of focus or not as sharp.. Also the K5 colour was more of a purple when focusing on a grey area where the K10 was spot on colour matching. I have also noticed purple fringes aroung a lot on my shots in full sunlight and doesnt matter what lens I use. Most of my lenses are from the Pentax FA*2.8 range and the 10-20 in the only non Pentax lens I use.
I think I need to sort out hte focusing problem before I go any further on Panos. I have been using Photoshop CS4 to stitch my shots together. I normally only go for about a 180 X 90degree wiew.Although I would like to try more at a later date.Thanks for your help so far.

John

[hansnyberg]

If you had read my article I posted in your last post you should understand why you have problems.
Here it is again.
http://www.panoramas.dk/panorama/foc...gle-focus.html

Hans

[campdog]

Thanks Hans. Your help is appreciated greatly.I dont think the problem is just with the Sigma 10-20mm but all my lenses and It just dosnt happen when making a pano.The out of focus areas are in each single shot before joining. I will have another read of your article but feel I need to sort out the K5 before moving on.To take 2 shots of a brick wall with same lens and same settings but different cameras and one to be in focus and one not.Can it still be the lens or the camera.
John

[Hugh]

Thanks for the link Hans, makes interesting reading not to mention some great panoramas!

I guess that lens design = intended use and the information on this link shows why metric lenses for photogrammetric cameras cost such huge amounts of money.

I would still be interested in others opinions of the Sigma 10-20mm lens as I do use one for panoramas that are above and below the horizon (i.e. not Spherical Panoramas although I have experimented with a couple) and have not found a problem with it fitted to both a Nikon D60 and D300.