Homemade pano attatchment.

[Don Hoey]

Panoramics are something of a rarity for me. I did one recently at Castle Acre shooting in vertical format, and due to parralax error I had quite a trial joining them together in CS2. A week ago we were in Norwich and popped into the Forum for a coffee. Inside the forum there there is Fusion a digital screen gallery. The screen is in a curve and measures 24metres wide x 2.5metres high, so any display that takes all that up is very impressive. On that day the pictures were all by Norfolk and Suffolk based photographers. Naturally due to the screen dimensions there were a lot of panoramas being shown. Over a cup of coffee I had a ponder about my experience. Bitten by those superb images I determined that I would have a go at panoramas, but it did have to be at little cost.

I cracked up when I saw the prices of Panoramic Heads , but I had the bug now, so the question was how to do this for little spend. A trip to a hardware store and things were on the up when I bought a two orientation bubble level for 84pence.

Workshop time now, and I dug up a couple of offcuts of 40mm bar. With one I made a rotating base and the other I machined to form the base section. The rounded end has a dovetail cut into it so the bar that supports the camera is easily attatchable/detatchable yet solid when locked up. The base section has two threaded mounting holes, these are in line with the centre of the lens, so one is for the D2X and the other the D100. Now I realised I needed to align the point of rotation closer to the centre of the front element of the lens to eliminate parralax error. Luckily I have a Manfrotto 501 fluid head which has a sliding plate. Using this would also allow for tilt movement, so an advance on just using the single rotator, saved having to make another rotator for use at the camera mount. I did though have to make an additional base that could be really tightly screwed to the Manfrotto's sliding plate. The Manfrotto plates have rather high rubber inserts, and from previous experience you just cannot sufficiently compress that to avoid bounce with a single screw on a smallish foot. I still had to use the rotator in the final setup in order to align the bracket base when mounted. I was not clever enough to get both thread starts in exactly the same place on the base or I could have dispensed with it. It does make for easy mounting of a camera for normal tripod shooting, so I guess there are ups for some downs.

The 501 head is super stable and mounted on the 055 legs is good for general out and about. For serious stuff I would attatch it to my big Slick Proffessional with the 405 geared head. Lots of weight in that combo though.

So four days later and a bin full of swarf the result is in the attatched pic. All up cost probably around a fiver.
If the weather is on our side I will give it a bash tomorrow. Full of confidence that I do not have to modify it.
Now you know how come I have not been on WPF for a few days.

Don

[Canis Vulpes]

You have a true talent in the workshop and combined with your equally impressive photography skills I am confident the results will be perfect.

Please post some images as and when you create them.

[Don Hoey]

Ha, ha Foxy,

Normal rules to getting new kit seem to be applying. Either diabolical featureless grey skies or loads of rain, so a play seems a bit off at the moment.

In fact so dire is it today, I've taken time to do a pic and a couple of grahics to hopefully better explain what this is all about. I'm quite sure those with fancy pano programs are probably thinking I have gone a bit over the top with this . I am restricted to manually doing the stitch in CS2, so for me it helps to eliminate as many variables, like parallax error, as possible before taking the series to be stitched.

The first graphic illustrates my starting point. I figured if you are going to do a pano, then a single strip done with the camera in portrait orientation is easier to manually stich than a two row job done in landscape format. As can be seen from the graphic the D100 has quite an overhang from the tripod centre in portrait orientation, but even though the wooden bridge was over a hundred yards away I still had alignment problems through parallax error. This probably would not have been so obvious in landscape as the parallax error would have been seriously reduced.

The second pic better shows the location of the lens centre and its relationship to the centre of rotation. This obviously becomes critical if near objects are to be included and less so for distant objects. Out of interest I marked the centre of the camera tripod mount and the sensor plane.
As a change from post#1 I have added the sliding plate attatchment as I have a spare plate for that, so I can easily change the 501 head between applications without the need to unscrew everything.


The next graphic is my easy method of lens centering. Yes I fell over articles on Nodal Points, lots of tech talk and formulas that just made my brain hurt. So I did it the nice easy way as in the graphic. Tripod/camera set up in the workshop and six feet away I placed a table with two 10mm bar ends spaced 30 inches apart. The camera was lined up so the bars lined up. When the camera is forward of the lens centre and it is rotated, the further bar moved left or right. The further forward of the lens centre the greater the movement of the further bar. Once lens centre is achieved the rear object does not move relative to the front object. Two sharpened pencils would work just as well for this.

I intend using two primes, a 20mm and a 35mm and luckily they both centre within 1mm, not too worried about that and I only marked one index point on the sliding plate. Proof of the pudding was when I found this site which lists a number of lens centres, and the 35mm is spot on with that, measuring lens centre to sensor plane.
http://www.swissarmyfork.com/lens_table_1.htm
For pano you need to look at the column marked ' Entrance Pupil '. This link also illustrates that with zooms that centre point moves with change of focal length.

Don

[wolfie]

Looks extremely professional Don, now you're into panorama's can we expect something like this http://ovincez.smugmug.com/gallery/9...057_DKAU5-O-LB

Canon 5D mk 11

Harry

[Don Hoey]

Harry,

No chance of anything like that from Norfolk. We are famed for our big skies. No mountains or hills getting in the way.

Don