Template epiphany

[jedlovec]

I have aggressively worked to achieve a reasonable template with my Canon 5D + 15mm FE lens using the precision 360 absolute with both the bar and pin camera mounts (the pin mount is more repeatable but not good enough - see below). I trace the problem to repeatability of installing and removing the camera from the mount. I find this to be on the order of + or - 10 pixels and I wonder what anyone else' experience might be? Furthermore, this repeatability may be a metric that will allow one to determine if a particular head is capable of providing a reasonable template.

I tried to obtain many templates per the calibration instructions under many conditions (bathroom, large garage, small closet) and while most gave me pixel errors < 1 pixel for a 6000 pixel wide create panorama setting (using at least 20 control points between images), none will give me a template that stitches the zenith accurately. I am now convinced that this problem results from the poor repeatability when connecting/disconnecting the camera from the pano head.

My repeatability test is as follows:

1. Epoxy tripod legs to concrete floor. Hang one gallon can of paint from bottom of tripod for added stability

2. Attach camera to head. Level head.

3. Shoot 3 consecutive images at same click stop. Repeatability is one pixel.

4. Shoot image, rotate 6 click stops (360 degrees), repeat two more times, repeatability is 1-5 pixels

5. Shoot image, remove camera from pano head, then reattach, repeat two more times. Repeatability is + or - 10 pixels!

Any comments? Should I get a new pin mount plate?

Thanks

[PanMan]

Hi,

From what I noticed so far most repeatability problems occur because of the tripod. You seem to have reasonably excluded the possibility of tripod movement, but how about twisting ? How sturdy is the tripod, what model ?

4. Shoot image, rotate 6 click stops (360 degrees), repeat two more times, repeatability is 1-5 pixels.

This is totally atypical, the repeatability should be perfect.

2. Attach camera to head. Level head.

Are you using a ball head or a leveling base ? In this case you should mount the 360P head directly on the tripod.

I tried to obtain many templates ... none will give me a template that stitches the zenith accurately.

Manual or automatic control points ?


Let's take it step by step, I'm sure we can find the problem.

[jedlovec]

Thanks for the offer.

This is my tripod (good quality, sturdy):
http://www.bhphotovideo.com/c/product/5 ... lack_.html

This is my leveling base (head mounted directly to leveling base):
http://www.bhphotovideo.com/c/product/5 ... _Base.html

In my test I am extremely careful about twist. But in the field shooting panos you would also have to be. Both leveling base and pan head are tightened on.

I obtain manual control points as per Matthew's template calibration instructions posted on this forum.

Neither the pin or bar mounts are kinematic but acc. to what I am hearing this does not matter. Could you repeat my third test and see what your results are?

Don Jedlovec

[PanMan]

I can find no repeatability problems.

Could you repeat your test without the leveling base ?

[jedlovec]

I tried. Same results. I may not be making it clear just what my 3rd test is:

I epoxy the tripod legs to a concrete floor.

I hang a 1 gallon full paint can from the bottom of the tripod for added stability.

Then attach camera to the 360 absolute head - 5D pin mount.

I level the head and tighten the leveling base holddown screws.

Shoot photo1, pitch =yaw=0.

Disconnect camera. Reattach camera. Shoot photo2.

I then compare photo1/2 as two layers in photoshop and find that one photo is offset from the other in the pitch direction primarily, buy 7-12 pixels. This offset is worse with the bar type mount. Is this normal?

My pin has a nice tight fit but there is play in the shoulder screw of the 360 mounting plate (for both the pin and bar mount plate options) which would translate into offset in the pitch direction.

Shall I send some sample templates, as maybe I am getting that part wrong?

Thanks

[PanMan]

Hi,

Don't worry, we'll try to identify your problem.

Please contact Matt through the Online Support Desk, because the forum is used for more general questions:
http://www.360precision.com/360/index.c ... ainnavID=9

[jedlovec]

Dear panman:

I have been trying to contact matthew per your guidance through the online support desk but have yet to hear from him.



Please contact Matt through the Online Support Desk, because the forum is used for more general questions:
http://www.360precision.com/360/index.c ... ainnavID=9