PDA

View Full Version : Bubbles...



tgtaylor
2-Jun-2013, 19:03
The water in the bubble level indicating tilt on the front standard of my To yo 810G was dry. So instead of spending the $40+ to replace it with a new level, I decided to switch with the level on the 45C which see little use since I prefer the ROBOS instead.

Yesterday I was out shooting with the 810G and as it is my procedure I level the tripod according to its bubble levels and then level the camera according to its bubble , and then go under the focusing cloth to focus the camera. But when I Gert under the cloth part of the frame is in focus and part slightly out of focus. I then double check the levels and all 4 are centered but the image on the ground glass is still partly unfocused.

After carefully eyeballing the perpendicularity of the front and rear standards (my sudden fear was that I had somehow bent one of the standards) I noticed that the tilt indicating section on the front standard level was upraised slightly from the standard and that there was a small black object underneath. Could it be that I made installed other level over a protruding screw? Was the level itself warped?

I made the necessary mental adjustments at the shoot yesterday and when I that home removed the bubble. It turned out that the object that I thought might be a protruding screw was in fact a small piece of black finish paint that apparently had become dislodged from the 45C and had repositioned itself in the vertical position preventing the level from laying flat on the standard.

I'm glad that it turned out to be a flake of paint instead of a warped level because that saved me ~ $45 in replacement costs. I've also learned in the past to check that all movements are truly in the neutral position before beginning to focus. These cameras are extremely precise and it is easy to inadvertently change the alignment by simply lifting it out of it's case and onto the tripod.

Thomas

Doremus Scudder
2-Jun-2013, 23:54
It doesn't do much good to just install a level without checking to make sure it is installed level...

You need to set everything up and check with good quality levels to make sure the standard you wish to mount a level on is, indeed, level and plumb. Then you can mount your level and shim it as needed so it reads zero. Depending on the accuracy of your instruments and skill mounting the level, you will then have a fairly accurate level mounted on your camera.

Just sticking a level in the old hole and gluing it in place is not really good practice...

Best,

Doremus

Jonathan Barlow
7-Jun-2013, 11:37
Your post reminded me of a newspaper article from 2007:

http://www.nytimes.com/2007/08/20/us/20engressia.html?_r=0

Heroique
7-Jun-2013, 12:16
Some people excel at preventing problems (Doremus), others are good at figuring out what’s causing them (Thomas).

If you’re an LF photographer, both skills are great to have!

Neither skill prevents the need for the other.

-----
Periodically, I’ll set-up my Tachi in the living room, neutral positions, and check standards and bed w/ a quality level. In the field, I use a small, pocket carpenter’s level that agrees with the quality level.

Daniel Stone
7-Jun-2013, 12:35
I (NEVER) trust the on-camera(built-in) levels. I use the g/g.

one benefit of using a large(ish, 5x7 in my case) format :)

I put the card([Ebitsu(see below link), about $9ea) on the inside part of the g/g frame, and "level" starting with that. If I want the rear frame to be completely vertical, I put the card level against the g/g directly, so I can check to see if its truly plumb, or not.

http://www.leevalley.com/us/gifts/page.aspx?c=&p=48816&cat=4,104,53217

Takes about 10s to get it leveled w/ a pan/tilt head.

some cameras don't allow the g/g to seat exactly "snug" in the frame, to allow for thermal expansion/contraction coefficients of the glass. So a g/g that has a grid on it can sometimes get jarred out of "alignment" during transit/handling.

-Dan

Ari
7-Jun-2013, 12:40
You might find this article helpful, if you want to go the repair route: http://photo.net/large-format-photography-forum/00O6zI

Vaughn
7-Jun-2013, 13:46
I (NEVER) trust the on-camera(built-in) levels. I use the g/g....

-Dan

Same here...it is the image that matters, not the level of the camera...at least with landscape work. We (LF'ers) tend to tweak things with swings, tils and shifts, anyway. Camera level is just another tool like those. I have used the tilt of the entire camera to 'correct' leaning trees if the image calls for it.

But I can easily understand that some folks wanting to 'know' that their tripod and camera are all zeroed out and leveled to start out with. Just not necessary for me.

Vaughn