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-   -   Camera Not Level On Tripod (https://www.dvinfo.net/forum/canon-xh-series-hdv-camcorders/238239-camera-not-level-tripod.html)

Daniel Fessak June 30th, 2009 05:04 PM

Camera Not Level On Tripod
 
The last few times I have set up my A1's on tripods, I have not been getting level shots. The bubble level on the tripods show that they are even, but when I go back and watch the footage everything is on a slight angle.

I thought that maybe the floors were not even throughout the location I was shooting in the first time it happened. But it happened again the next two times I shot on my tripods. I have no idea why this is happening. Any ideas? Me just being stupid has crossed my mind. I can not trust my eyes for a level shot because when I do and I'm wrong, it's worse than what I get on the tripods.

Very frustrating because I wind up wasting a lot of time when editing trying to cheat to hide it.

Bill Koehler June 30th, 2009 05:25 PM

To make sure my tripod+camera are on the level...

One of the steps I do when setting up is to find a room horizontal reference line, preferably at my height (I'm often in the balcony) and directly opposite in the room. I then zoom in on it, adjusting the legs of the tripod to make sure either the top or bottom of my picture is absolutely parallel with that reference line.

It only takes a minute or two to do.

Daniel Fessak June 30th, 2009 07:41 PM

But why is the camera not level if the bubble level says it is?

Battle Vaughan June 30th, 2009 08:15 PM

The level shows that the head is level. Two possibilities, then: the camera is not sitting squarely flat on the head, or the level is cocked..../Battle Vaughan

Bill Pryor June 30th, 2009 08:34 PM

I'd vote for the level being skewed.

Chris Soucy June 30th, 2009 08:41 PM

Hi Daniel.........
 
One thing to try and find the source of this is to dive into the A1's menu in a shooting mode, [DISPLAY SETUP], Select [MARKERS] and set it to [GRID].

Your A1 will now display two horizontal and two vertical lines in a cross hatch pattern on the display when shooting (no, they are not recorded).

Just remember to check these with any available horizontal/ verticals in the frame before shooting.

As Battle said before, if the bubble on a half ball/ bowl head says it's level and it's not, either the camera/ head interface is stuffed or the bubble is.

I say "half ball/ bowl head" specifically, as they are designed for video cameras.

I have seen tripods designed for stills use that have a bubble level on the receiver (the bit the legs attach to) and when it's leveled, the camera mount platform can still be miles out, as they have a "flip" option to shoot portrait - if that is not set properly the platform can be anywhere from horizontal to vertical!


CS

Anthony J. Howe July 1st, 2009 03:40 AM

I have found a few times where the horizontal level appears to be slightly off, but this has been with three cameras I have used, Sony, Canon and Panasonic.
I have been able to get it almost right, but with the Canon, you have the level line or the grid (in the menu) as mentioned above, to me it's been a God-send, thanks to Canon.

Tony Davies-Patrick July 1st, 2009 05:50 AM

In nature almost everything is curved and nothing is perfectly straight or parallel, even the horizon.

Most modern man-made objects and structures are very straight, and so our minds are taught to 'need' to have everything parallel or in line with vertical and horizontal lines.

It is a simple fact that a framed picture hanging slightly askew to the straight lines of the walls and structures, immediately shouts at us to adjust it to the correct position - even though that picture might possibly be hanging correctly in accordance with a spirit level.

The eye and brain takes notes from the whole view and makes instant adjustments to take into account sloping hills, slanting walls and floors etc. But when we are presented with only a two-dimensional partially framed view of a small section of that same scene our eyes only see the straight lines.
So if the slanting floor/wall/hill is the only straight line that is viewed in the scene then it can appear that the camera is not level, even though it actually is.

In these situations it is often better to line-up the camcorder with the straight horizontal and vertical walls/windows etc or similar subjects outside (and ignore the spirit level reading). If the eyes only view the subject framed in the footage it will be 'fooled' into thinking the slightly sloping horizons are straight.

Shooting footage from a locked fixed position on a flat floor is usually easy to handle and get right, but pans from a sloping floor or hillside (with the tripod legs and head adjusted to compensate) can be another matter entirely. Sometimes when the spirit levels are all showing perfect alignment at the beginning of a slow pan, the horizon can slowly begin to dip halfway through the pan.

The slight curvature of some wide angle lenses can also add extra problems during even a short pan, especially straight buildings, doorways and windows etc. at the edge of the frame.

My Vinten and Manfrotto heads each have at least two separate spirit levels and I am constantly using them to help keep horizons etc., parallel in the frame; but occasionally, depending on subject matter, it is wise to simply ignore them.

Doug Bennett July 1st, 2009 08:45 AM

Tony

your tripod heads have 2 spirit levels?

Constantly adjusting to keep horizons level? Ignoring them altogether? Are you shooting on a ship?

Brian David Melnyk July 2nd, 2009 10:46 AM

i have also found that if you level shooting straight on at a wall, and then if you pan left or right, the 'horizon' line will look off due to, i think, the lens and an optical illusion and ummmm science that i don't know... even if panned just a tiny bit, 'level' looks off... probably more noticeable at the wide end.
anybody know the name for this effect so i won't sound so half baked next time?

Annie Haycock July 3rd, 2009 03:07 AM

Optical aberration

It looks more obvious at the wide end because of barrel distortion - a common problem with wide-angle end of zooms, the longer the zoom and the wider the wide angle, the worse the problem. Your brick wall will show the lower line of bricks apparently curving down in the middle, and the upper line curving up (well, my camera shows it on sea horizons). The solution is to put the horizon straight across the middle at wide angle.

A wide angle lens needs a lot of curvature to cover the wide angle, so as you zoom in and use only the centre part of the front lens (still using most of the width of the internal lenses) the distortion "disappears".

The opposite is pin-cushion distortion in which the centres of the outside of the frame get pinched in towards the centre of the picture. see http://en.wikipedia.org/wiki/Distortion_(optics)

Tony Davies-Patrick July 3rd, 2009 04:42 AM

Quote:

Originally Posted by Doug Bennett (Post 1165718)
Constantly adjusting to keep horizons level? Ignoring them altogether? Are you shooting on a ship?

Yes, I'm sometimes shooting from a ship, boat or canoe...but not in this case. Lol!

Doug, if you read my entire post you will know that I am talking about 'certain situations' where it can sometimes be wise to ignore the spirit level readings to obtain footage that looks more 'correct' to the eye.

Of course in most normal situations I use the spirit level readings to help me obtain level horizons etc. The vast majority of my work is outdoors on uneven terrain and over the course of a day or night of shooting I will need to carry the tripod to a variety of locations and be forced to move the tripod, sometimes many times in short succession up and down hills, in and out of water etc. So, yes, in that sense I am constantly using them to help keep horizons parallel in the frame.

Philip Younger July 3rd, 2009 05:45 PM

Daniel: It's funny you should mention this because I have had a similar problem only with hand held. I thought it was just me not holding the camera level as a recent shoot showed a known horizontal line to slope upwards to the right.

I went back and did the shoot again making careful note to ensure the horizontal line ( a dado rail in the room) was level in the viewfinder screen it was, yet again on the downloaded film there is a slight upward slope to the right. To most people this would not be noticed in this particular shot but to me editing the footage it stands out a mile!

Unlike Daniel - the o/p - when I then re-shot using a tripod and ensuring the bubble was spot on, the footage was fine, however, the scene in the viewfinder looked as if it was on the tilt. This makes me think the viewfinder is not set quite right, or the recording head is up-the-duff in some way, seems like it's probably something out of my control.

Taky Cheung July 4th, 2009 12:09 AM

I always ran into the same problem. So I add this interface to my bogen tripod

Manfrotto 3502 - Compact Camera Leveler

It works very well.

Chris Soucy July 4th, 2009 10:42 PM

So, Daniel..................
 
You have your answer yet?

Someones had to have nailed it!


CS


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