[deadalvs]

hi.

i got a question concerning this link:

http://www.mab3d.com/temp/ot3d/3shothdr1.html

what is the reason that the camera is shooting tilted ? the lens produces 180 degrees in both directions, right ? so the camera could also look straight horizontally while just rotating 3 times 120 degrees vertically...

what's the reason ??

[leoA4D]

The answer, I believe, is in the first paragraph of part 2 of that article: http://www.mab3d.com/temp/ot3d/3shothdr2.html

Edit: There is also a free hdr at the bottom of part 2.

This is a good article, thanks for posting.

Leonard

[deadalvs]

hmm... yeah, i had read that... but ...


that lens has 180 degrees horizontal AND vertical viewing angle... so from nadir (tripod) to zenith, there's all in that picture... just turning three times @ 120 degrees around to get the full «sideways» pano ...

i'm missing some point ...

[simmsimaging]

The lens has that field of view, but unless you have a full-frame sensor camera (which he does not - you can see in the pics in the second link that Leonard posted the circle is cropped) you have to add the zenith and/or nadir.

By tipping the camera slightly up or down you can catch either the zenith or nadir with a non-full frame camera, but not both. As he points out though - for CGI stuff you don't often need the ground/tripod area anyway.

b

[deadalvs]

ah i see !

okay... one question:

i have a nikon d40x camera -->

a quote from here

Lens Description:
Sunex SuperFisheye lens is a new type of fisheye lens developed exclusively for digital SLR cameras using APS-C or DX format imagers. Unlike other fisheye lenses, Sunex SuperFisheye forms a complete circular image within the camera imager area.

such an image taken with my camera, a linked image from there:


so the question: since that image is fully circular and has a viewing angle of 185 degrees, i could basically create a full stitched pano with just two photographs, right ?

i'd like THAT:

[deadalvs]

it does work:

http://www.kenrockwell.com/sunex/super-fisheye.htm#spex

Coverage: 185 degrees

Compared with the 180 degree Nikon 8mm f/2.8, the Sunex covered just a tiny little bit more. This is irrelevant for conventional one-shot photography, but is most likely the difference between having enough overlap to get away with a two-shot 360 x 360 panorama, or not.

[bbuxton]

A good full circle lens for Nikon fit dx cameras.

http://www.warehouseexpress.com/product ... ku=1024102

I don't see any particular need to tilt the camera other than to use certain lenses, perhaps to sqeeze out a marginally higher resolution panorama.

Also stitching tilted shots is more hassle than regular stiching - a few extra steps.

A good pano head is the nodal ninja - its very cheap - compact and light and surprizingly sturdier than my ancient kaidan head QuickPan III. Both the sigma 4.5mm & 8mm fisheyes are excellent for shooting hdr panoramas.

Let me know if you want to see some samples shot with the sigma 8mm or look at some I have for sale at http://www.paralumino.com

BB

[simmsimaging]

it does work:

http://www.kenrockwell.com/sunex/super-fisheye.htm#spex

Coverage: 185 degrees

Compared with the 180 degree Nikon 8mm f/2.8, the Sunex covered just a tiny little bit more. This is irrelevant for conventional one-shot photography, but is most likely the difference between having enough overlap to get away with a two-shot 360 x 360 panorama, or not.

I'm sure it does.

Having the full circle in frame will mean you won't have to tip up or down or shoot nadir/zenith shots - but I would guess your final pans would be somewhat lower res. How much I don't know, but if you are using a smaller piece of the sensor it would seem inevitable right?

As far as shooting in two shots goes - even if you could it would mean that significant areas of your panoramas would *only* be captured on the edges of the lens where distortion and chromatic aberrations are at their worst. You panoramas would be of higher quality with more angles - it's a trade-off for efficiency over quality. Whether it's good enough for your purposes is something only you can decide. I would suggest finding a good pro shop and rent the lens options and try them out before sinking any serious money into it.

b

[deadalvs]

thanks for the input, guys.

the site where i linked the images from is actually a site with a test of that actual lens:
http://www.kenrockwell.com/sunex/super-fisheye.htm

so i read it thru and it really seems that because the lens is build very solidly and is fixed you get similar results with it as with the nikon that bbuxton mentioned just above which is a BIT more expensive.

of course using three images will result in a better solution than with just two overlapping 2.5 degrees on either side. so what i'd do is go for the pano head which is available directly from sunex built exactly for that lens... so there would be no fuss finding the nodal point of the lens ... that'd be an advantage. and that head has three 120 deg markers already fixed. the issue that the camera itself is kinda lo-end anyway is also a limiting factor...

but my main goal is to pull hdrs from bracketed exposures which are combined to an .hdr in ps cs3. that .hdr could be used for lighting and reflection map and would not have to be perfect...

most of the time in my work i'd use a «simple» photographic background plate to composite anyway.

so i guess spending *too* much money for the end goal in my workflow is not my goal either...

[bbuxton]

The only issues I can see with the Sunex lens used with a D40x are metering & the bad fit to the Nikon body. If you can use a D200 or D300 you can set for non cpu lenses but the D40 would require trial and error which would slow you down.

I use the 8mm sigma and shoot 4 shots horizontally (every 90 deg) and 1 straight up. This is very quick and stitches very well.

The Agnos angled plate is good if you are using the Nikkor 10.5mm dx fish eye.

Agnos also do a lens ring (that you leave on the lens, making set up accurate and quick) for the 8mm fish eye & soon will release one for the 4.5mm - allowing 3 shot panoramas (2 if quality is not an issue).

The 8mm fish eye gives about 8000 pix horizontal resolution & the 4.5mm around 6000 pix.

Anyway for your camera I think the Sunex will be a pain. If you get a D200 or D300 I think it will have an edge over the Sigma lenses. The Sunex will also suffer when shooting in very bright light as I can't see a way of using ND filters and there is no flexibility without an adjustable aperture.

BB

[deadalvs]

what type of trial and error you mean ?

what`s the advantage of cpu / non-cpu lense ?

well... a new camera is not an option for me...

what would you suggest then for me ... i mean i`m lo-end in this area !

* * *

an other question. most tripods aren`t capable of turning and holding the cam perfectlt horizontal while turning around... does that matter a lot for stitching ?

[bbuxton]

Personally I would go with the Sigma 8mm fisheye. £350
For the pano head use the nodal ninja £170 (one of the best and cheapest!)
It's important that everything is level or stitching will be a nightmare
FLM do a nice very compact leveller for £50

The Sigma 4.5mm is £600 and allows 3 shot panos but I prefer the 8mm shooting 4 or 5.

The 4.5 is usefull for sky shots though (no stitching required just shoot pointing straight up). Both can use ND filters (behind the lens) for shooting in very bright conditions.

CPU lenses talk to your camera so it knows what aperture your shooting etc. Not only does this help setting exposure whilst shooting it gets written to the files exif data and is used when building an hdr from bracketted shots.

http://www.warehouseexpress.com/product ... ku=1024102
http://www.red-door.co.uk/pages/product ... d-nn3.html
http://www.speedgraphic.co.uk/prod.asp? ... lling+Base

BB

[deadalvs]

so many questions coming up ...


i've seen that there must be two sigma 8 mm lenses available... a f/3.5 and a f/4 one... is that correct ? because it is mentioned here:
http://www.agnos.com/prodotti.htmv_ling ... 0004-P0401

the sigma homepage shows only the 3.5 one:
http://sigmaphoto.com/lenses/lenses_all ... avigator=4

* * *

would that sigma 8mm lens create a full circle on my cam ?
because here it says:

*Full circle can only be captured with full frame 35mm format digital SLR and film SLR cameras.

* * *

that seems very useful !


what are the most important points when choosing a tripod ? i mean buying a leveller as you mentioned is okay for one leveled shot, but when you turn around for more shots it's certainly possible that the tripod bends a little based on momentums. what can be done to avoid that ?

* * *

what stitching software do you use to create hdrs ?

what workflow ?
a) stitching a pano for each exposure setting and merge then to hdr
or
b) merge all exposures to hdr first and then stitch the hdr, as for example with http://hugin.sourceforge.net/ ?

* * *

many questions, i know ... but i'm very thankful for clearing this up !

[bbuxton]

If you really, really must have full circle on your dx camera then you will have to go for the 4.5mm sigma (£600).

The old 8mm f4 Sigma has been superseded by the 8mm f3.5 which is much better and almost as sharp as the Nikkor 10.5mm fisheye.

Unless you want to do interval shots of the sky (animated hdr skydomes) the 8mm fisheye is much better. Higher resolution results, much sharper captures and easier to stitch due to less distortion.

Whether you make your shots hdr prior or after stitching is down to preference or the software you use. I usually do it after as patching out the tripod & other clean up is easier on an 8bit or RAW image.

I use realviz stitcher unlimited for stitching, photomatix for making hdrs & photoshop CS2 for patching etc (when I upgrade to CS3 Ext I will most certainly make the shots hdr prior to stitching as the workflow is a bit quicker). I use a few other tools to make life easier too.

I seperate my shots into exposure sets and batch em through stitcher.
I use cubic converter to make the panos into sets of 6 cube faces then patch/clean up then reassemble in cubic converter before batching in photomatix. - all the above software can batch tasks which means more coffee & less work

There are plenty of cheaper & even free alternatives but I like the software above.

Don't get a bendy tripod!!! I have a Manfrotto 055Pro and it is like a rock. It doesn't move unless I trip over it. That said use a remote release!! any flex will settle between shots & the stitching software can compensate a little. A lighter alternative is the Manfrotto 190xb pro £90 Don't use carbon fibre too bendy!!!


If you are local to London send me a PM and I'll take you out to practice with my rig before you spend any money!
I have a job coming up in Greenwich Park & could do with a hand

BB

[deadalvs]

thanks man... if i only lived near the UK at the moment i think i'd come !

i come from switzerland (near zurich) but i am currently in west hollywood taking 3d classes for half a year. so i won't be back in europe till mid september !

but being an architect myself (finished my studies at the ETH in zurich last july) and doing viz most of the time i think a good camera rig is a must for a professional.
do you often work with shift lenses too ?

the next crappy thing is that my d40x cam can not even shoot bracketted exposures automatedly !! (they took out the feature just on this model to simplify the usage ....) i mean this could ruin the whole idea of shooting hdrs since you have to manually adjust every shot and thus touch the cam for each shot !

* * *

as seen in this image here i'd not need to buy a head for a new metal tripod (for example the manfrottos you mentioned), since it has a level bubble... that's good !