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-   -   Attitude Indicators in View Finders (https://www.dvinfo.net/forum/open-dv-discussion/488983-attitude-indicators-view-finders.html)

Hamish Reid December 15th, 2010 10:51 PM

Attitude Indicators in View Finders
 
I can't be the only person who's had trouble getting his or her camera level in a hurry and wondered whether there's not some sort of in-camera solid state gyro system that could be used in future cameras to display something like an attitude indicator (yes, I fly) or artificial horizon in the viewfinder or LED display during setup....

Does anyone do this now? It'd sure make it easier than trying to simultaneously see the tiny bubble on the head while shooing people around the tripod and trying to set everything else up for a rush shot :-).

Ken Hull December 15th, 2010 11:23 PM

Strain gauges
 
You don't need a gyro system. Strain gauges have been used in oil drilling for years, to determine the attitude of a steerable drill bit. You would need one strain gauge to measure left/right tilt (or roll, to use an aeronautical term), and one to measure fore/aft tilt (or pitch). The strain gauges I saw, about 30 years ago, were about 1 inch by half an inch. I suspect that much smaller ones can be had today.

I'm not aware of this technology being using in cameras. I remember messing up many hand-held shots with a visible but tilted horizon. An attitude readout would have helped a lot!

Ken

Min Lee December 16th, 2010 01:24 AM

I believe the Sony z7 have some level indicator. May be other cameras as well.

Brian Drysdale December 16th, 2010 03:34 AM

These systems can run into problems when you move the camera, a spirit level doesn't work when you move the camera sideways.

Regarding tripods, the biggest problem tends to be levelling it up in the dark

Garrett Low December 16th, 2010 11:25 AM

Quote:

Originally Posted by Hamish Reid (Post 1599042)
I can't be the only person who's had trouble getting his or her camera level in a hurry and wondered whether there's not some sort of in-camera solid state gyro system that could be used in future cameras to display something like an attitude indicator (yes, I fly) or artificial horizon in the viewfinder or LED display during setup....

Does anyone do this now? It'd sure make it easier than trying to simultaneously see the tiny bubble on the head while shooing people around the tripod and trying to set everything else up for a rush shot :-).

Hamish, what tripod and camera are you using? All cameras I've worked with have some kind of safe area or guidelines on the display that will allow you to tell when your shot is level with surrounding horizontal cues when shooting hand held. Any decent tripod for video that you'd be using in the field should have a bowl. It takes me less than 5 seconds to level my camera once on the tripod. Like anything else it takes some practice and learning a good technique that works for you. In a lot of situations I'm constantly moving my rig for a better shot and it's just part of my routine to level every time I move. Once you've leveled the head, as long as you don't move the tripod you don't need to level it again. For dark situations it really comes in handy having a tripod with a self illuminating bubble. If yours doesn't, get one of the very small led flashlight and keep it in your pocket. When you need to level your head, hold it in your mouth while leveling.

Quote:

Originally Posted by Ken Hull (Post 1599049)
You don't need a gyro system. Strain gauges have been used in oil drilling for years, to determine the attitude of a steerable drill bit. You would need one strain gauge to measure left/right tilt (or roll, to use an aeronautical term), and one to measure fore/aft tilt (or pitch). The strain gauges I saw, about 30 years ago, were about 1 inch by half an inch. I suspect that much smaller ones can be had today.
Ken

Ken, I'm an engineer so maybe we're talking about different things here, but I'm not sure how a strain gauge would help? Strain gauges measure deformation or movement of an object. They don't tell you if something is level. The application you're talking about is used to tell if the bore hole is deviating from a set alignment. The main thing is that the alignment has already been set or in this case level would have already had to have been established.

Dave Blackhurst December 16th, 2010 03:07 PM

The new Sony SLT cameras have exactly what you're talking about, displayable on the LCD or EVF - haven't tried it yet, but sounds like a handy extra...

Rainer Listing December 16th, 2010 03:52 PM

Canon 60D has this.

Hamish Reid December 16th, 2010 09:38 PM

Thanks everyone for the comments and responses so far -- I suspect that something like this is definitely on its way. Who knows, it might end up feeding into a dynamic camera platform stabilizer one day...

In response to Garrett's points (thanks Garrett...): firstly, while the cameras I use all have display markers, I've learned over the years that there are situations where the visual clues are misleading or non-existent, and it'd be nice to know where that horizon really was, especially hand-held, but also for those long 270 degree pans (or whatever) on the tripod. Secondly, while I do have a head with a lighted bubble, the thing ain't what I'd call large (the bubble, that is), and can be a real fiddle to get right, and a nice large-scale display on a screen would be much nicer (reminding me of the welcome transition from small crappy steam gauges to the much larger, much more readable (and reliable, for that matter) electronic displays in the planes I fly). Plus I move my tripod *a lot*, and anything that might increase accuracy and utility would be welcome to me.

Dave Jervis December 16th, 2010 11:35 PM

I use a spirit level (designed for still cameras) that fits in the accessory shoe... a quick glance at that lets me level up the camera and I can generally maintain that for quite a while (handheld)......

There are very small LED indicating levels as well (also intended for stills cameras)....
red-amber-green(level)-amber-red indication of how level you are ("roll" only I think) .... might be more useful in the dark, but I have never tried one......

....I'd suggest taking a look at a photographic dealers website and search for "level"...

Both the "pitch" and "roll" of the panning head's mounting would have to be right for your 270 degree pan of course...so you're back to your bowl leveller and bubble (...some fabric tape round the end of the torch will give your teeth something safe to bite on...)

dave

Garrett Low December 17th, 2010 12:27 AM

Hamish, for long pans if being absolutely level that critical, the features in the likes of the 60D and Sony aren't going to be good enough. They are accurate only to 1 degree. I'm sure I can get much better accuracy using the bubble on my tripod.

Also, for me when going hand held, I'm not as worried about being exactly level with the whole world per se. I'm more interested in making sure that I'm level relative to straight objects. Or, in some cases, not level to relative objects that are in the frame.

-Garrett

Garrett Low December 17th, 2010 12:33 AM

Quote:

Originally Posted by Dave Jervis (Post 1599388)
(...some fabric tape round the end of the torch will give your teeth something safe to bite on...)

Oh come on, who doesn't like to chip a tooth on a hard metal object. LOL Honestly, that's a good suggestion.

-Garrett

Dave Jervis December 17th, 2010 11:02 AM

Tape on torch is not my original idea...nicked from a BBC camera assistant back in the '80s.... so credit where credit is due. d

Allan Black December 17th, 2010 03:06 PM

Hamish, imo it starts with getting your tripod set up correct. With my Miller Compass 15 on CF Solo legs, once I esablished my comfortable working height, I marked the legs for equal length on a dead flat surface so it's quick and easy to set the tripod up.

Repositioning outdoors, if the bubble is off and a slight tripod move to the left or right doesn't centre it, I re-level the head and mount the camera.

I have a thin strip of white tape on the side of my A1/s with coloured marks indicating the exact camera balance point for each set of accessories.

I see folk asking what do ppl have displayed on their VF/LCD .. yrs ago I learnt to compose and frame shots through the full displays on the LCD/VF if necessary .. and I use either the grid or the centre line to level the horizon. HTH

Cheers.

Claire Buckley December 20th, 2010 04:49 AM

Possibly of some help here is this LED device, The Kaiser Digital Spirit Level:



I find it very useful as I shoot hand-held and it gives me a quick confidence check as I shoot. It also sits nicely on the shoe adaptor of the Sony Z5 & NX5 for tripod mounted shots, which means, after I set up the bubble on a tripod and mount the camera, this little baby gives a final check.

The LED brightness and level setup is variable. The orange LEDS are within +/- 1 degree. Well worth a look. I keep the LED brightness fairly low. I have yet to change the batteries after using it on three wedding projects.

A little pricey but it solved my problem.

As for those dark locations, I use a little pen torch to set the tripod bubble and then the LED level does the rest.

Brian Drysdale December 20th, 2010 06:35 AM

Sounds like this levelling seems to be an issue shooting hand held with an external LCD rather than a shoulder mounted camera using a V/F. In that case, there are almost always enough visual clues and the image is so large that there's usually no problem about being level. It's more VFR than flying on instruments.

Giroud Francois December 20th, 2010 07:07 AM

i used once a different setup.
you can find laser line generator (basically a laser pointer with a cylinder lens) that generates a red line.
you just mount that under the camera and make the line just off the image.
so you can easily frame without even looking at the camera.
obviously everyone will see the red line so it is not for any situation.
(in that case it was to check mic position, the microphone has a white card or a reflector that showed if it goes too low , so the guy on the stick could exactly know how low he can go)

Giroud Francois December 20th, 2010 07:17 AM

a link to a cheap one
660nm 5mw Focusable Laser Line Module / Industrial/Test - eBay (item 250669491771 end time Jan-15-11 21:33:47 PST)

Bredly Root December 21st, 2010 06:19 AM

thanks for information

Hamish Reid December 21st, 2010 11:05 AM

Thanks again for all the further comments -- some interesting stuff here.

Anyway, I'll readily concede that I'm overstating how difficult it usually is to use a spirit level under normal conditions (hell, I spent a decade doing architectural and interior photography with view cameras, and a million years ago I was an apprentice carpenter / builder's mate...) -- I think all I'm really saying is that there are times I could really do with a larger-scale accurate display for those times when (like me) you're standing in the middle of a road and you don't have an assistant and you have about ten seconds to set things up... in the dark :-).

Ed Roo December 21st, 2010 06:22 PM

If you want to learn techniques for how to properly level a tripod, find a surveyor. Ask them to teach you how they do it.

Garrett Low December 21st, 2010 07:14 PM

Quote:

Originally Posted by Ed Roo (Post 1600843)
If you want to learn techniques for how to properly level a tripod, find a surveyor. Ask them to teach you how they do it.

I am an engineer and have done surveys. Many modern surveying devices are self leveling. Those that aren't have three leveling screws between the leveling plate and tripod used to make very fine adjustment. And, believe it or not, we use bubbles to tell if the instrument is level.

-Garrett

Allan Black December 22nd, 2010 06:08 PM

Handheld with enough practice through use, like the ENG guys you can level the cam by eye.

Cheers.

Sander Vreuls December 22nd, 2010 07:27 PM

A common trick in confusing studio's (with a lot of angles) is to put a spirit level on the top of the lens (or another part of the camera that is level, but top of lens is easiest to see on a shoulder camera). Even for experienced cameramen it's an easy trick to make sure your camera is level while quickly making shots..


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