panorama software,virtual tour software
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2012-09-28
#1

sigma 4.5 mm lens for pentax Kx

Hi; I would like to buy a sigma 4.5mm lens for my pentax kx; I think I will not have full circle with sigma 8mm.
What do you think about this lens un my aps-c.
Will I have good panorama?
I have a 10-17 mm pentax lens know; but it is too hard when I have to make a virtual tour with many places.
here you are link of lens:

http://digital-photography-school.com/sigma-4-5mm-f2-8-ex-dc-hsm-circular-fisheye-review

thanks a lot
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2012-09-29
#2
ok i will buy 8mm thanks a lot; other cuestion is if it is better pay a sigma lens or samyang o peleng lens; I ask that because lens has to be in manual and not automatic mode focus; so it is the same...; other thing is that sigma lens is better than peleng leng so the final image will be better with sigma than with peleng lens. Is that true?
thanks a lot

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2012-09-29
#3

Sigma 8mm f/3.5 version. Do not buy an older f4.0 version.

Sigma Fisheye is superior to Peleng in every way (except price!)

Yes, no need for auto focus (but still handy). Also when you have electrical contact with camera you pass on correct EXIF information.

Samyang make very good manual lenses. But no electrical contact with (most) of their range. Also no circular fisheye available (unless like me you have modified one). Typically Samyang fisheyes are 180 diagonal full frame (much like your 10-17mm fisheye).

The Sigma 8mm is the correct choice overall if you want to minimise the amount of shots on an APS-C sensor camera.

Regards, Smooth  


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2012-09-29
#4
thanks a lot; last lens i bougut was 10-17 mm pentax; and I would like to say it works very well; problem is that I have to make 9 shots for scene; I follow you how i should do four shots; here you are for link for everybody:
Click Here

Know, with this lens how should I make 4 shots? I mean degrees and the better position (like speed of shot and so on)

thanks alot
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2012-09-29
#5
The Sigma 8mm on APS-C requires 4 rotational shots at 90 click stops with +5 or +7.5 tilt up. Import into Panoweaver as "drum" type images. You still will need to shoot an extra down/nadir if you wish to remove the tripod.

This lens is sweetest at an aperture of f/8.0
You need to find it's best hyperfocal focus position and once found, tape the lens so the focus ring no longer turns. I use small black PVC electrical tape.

4x rotational shots at +7.5 degrees tilt up, @90 degree click stops. No Zenith shot required. 1x tilted tripod offset Nadir shot to cover tripod position. 4+0+1

It is possible if greater detail is required to shoot a Zenith shot and stitch it in. But it is not a requirement to create a normal panorama. The +7.5 tilt up will close the Zenith star.

Regards, Smooth
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2012-09-30
#6
thanks a lot; so i will f3.5 version

http://www.sigmaphoto.com/shop/8mm-f35-ex-dg-circular-fisheye-sigma

this is..
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2012-09-30
#7
Yes, this is the lens.
But do they make a lens mount for Pentax with this newer f/3.5 version?

Regards, Smooth
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2012-10-01
#8
i thinks so; I give you link; please, could you confirm me that this is the lens for my pentax kx?
because i see in the link that is is for a few pentax model but I dont see mine.
thanks a lot
I know I should ask them but I prefer you see link before askinf them, please.

http://www.amazon.com/Sigma-Circular-Autofocus-Cameras-Includes/dp/B006GTWUNE

thanks a lot

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2012-10-01
#9
Pentax is NOT my specialty.

But I found a different listing for the Pentax K-x Sigma 8mm f/3.5
http://www.amazon.com/Sigma-Circular-Autofocus-Cameras-Includes/dp/B006GTWLS8
The bad news is that it is more expensive.

Regards, Smooth
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2012-10-01
#10
Thanks for your link; I have write in a pentax foro about different; as soon as somebody write me about that, I will explain different ; by the way.....

You say you arent specialty with pentax; but the true is that you solve my problem when I bought pentax 10-17mm so
I ask you again; If I buy that lens (8mm f 3.5) with my pentax kx, Will I have good "drum" with 4 rotational shot and one more for tripod?. will I have a good fix?
thanks a lot

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2012-10-01
#11
Yes, you will get a good result after setting up.
You will have a new NPP to be found.
The final panorama will be smaller maximum size than that of the Tokina/Pentax 10-17mm Zoom Fisheye.

Of course the panorama size will still be fine for full screen panorama with the benefit/convenience of less shots.

It is hard to find better for the quality, size and amount of shots required on an APS-C camera. The Sigma 8mm f/3.5 Fisheye is best suited to cover all bases.

Regards, Smooth