Help working out mathematical formula...

[Astroman]

Hi all,

Currently i am making a timelapse camera slider with three axis of movement (lateral, pan, tilt) I want to be able to calculate with the pan and tilt, how far the axis should move in degrees, per time frame. So if in X amount of minutes, I want it to move Y amount of degrees... How would this be calculated, I am pretty sure it's a simple formula but I cannot get my head around it properly.

Help very much appreciated..

[Octane]

Isn't it just degrees divided by minutes? That will give degrees per minute.

Then, divide the answer above by how many exposures per minute.

So, say you want to move 5 degrees in 10 minutes:

5/10=0.5 degrees per minute.

If your exposures were 30 seconds each (2 per minute):

0.5/2=0.25 degrees per exposure.

Is that what you were after, or, am I missing something?

H

[N1]

I attach a quick spreadsheet that might help you. Check the result cells for the formulas. The frame interval is the gap you want between frames in realtime. The basic formulation is indeed straight-forward - it's the nitty gritty stuff that will really get you thinking. For example, consider the effect the movement of your contraption will have on long exposures (assuming you want to do TLs in low light).

Have fun

[Octane]

Mirko, very helpful -- thank you!

H

[Astroman]

Hi Mirko, that is exactly what I was after, thanks for that. I knew it was simple in terms of the formulas etc... but just couldn't get my head around it, probably too much other stuff in there causing a bottle neck...

[Astroman]

Any ideas if there is an App out there that does this or similar, I had a look at making my own app, but no idea where to start, other alternative is a spread sheet on my phone... need to make some space I think....

[coldknights]

Hi Andrew DP helper for iPhone !
Had that ap for about 2 yrs .

[Astroman]

Anything for android?

[coldknights]

Not sure ! when I got my dynamic perception dolly that app was made soon after and people were using it so for a couple of bucks we got the app have looked at it seems ok but not sure if they made a app for the Android.

[Astroman]

Yeah doesn't look like it. Never mind, I have Mirko's spreadsheet which is helpful. Almost ready to test my slider, just a couple more things to do to it...

[Merlin66]

I assumed it was an Alt-Az type arrangement...the movements (Up/down, left/right) would then vary with the position of the target object....
Not exactly an easy one....

[Bassnut]

Ive built this kind of thing, its not trivial. Ideally, for exposures over 1 sec anyway, you need to stop for the exposure as in a move-stop-expose-move cycle to prevent blurring. Also allow for ramps at the beginning and end of a sequence (or change in direction in any of the 3 axis) or the video will jerk awkwardly. Then another step up is non linear ramping profiles on stop/start/ and speed or direction changes. This all wildly changes movement calculations for a given required degree sweep for a sequence.

[Astroman]

This is for a 3 axis timelapse slider I am building. As you can see by the image below, there is lateral movement or left and right along the slider, up and down on the Orion Teletrack and also yawing from left and right on the Orion Teletrack.

The idea was if I knew the angle of the camera at one end of the slider, and knew the angle of the camera at the other end, I could use the calculator to work out the number of shots, how many degrees per shot the teletrack would need to move and also how long it would take. All this can be entered into the MX2 controller (black box).

I plan on making the Orion Teletrack to be able to be adjusted in it's angle from the slider so I can have it horizontal if the slider is at an angle. Hard to explain, I will hopefully have images at some point.