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parallax

Posted: Wed Nov 25, 2009 5:35 pm
by JPG
In another thread relating to bandsaw bearing noise, the subject of parallax
came up.

I submit the following so as to enable anyone who does not know or understand what parallax is to hopefully understand it and recognize when it occurs.

Parallax occurs when the vantage point of the observer(or camera) is 'off to the side' of objects so as to give the appearance that the relative positions of the objects is different than they actually are.

This can be demonstrated by holding both your arms outstretched, hands together, point your finger at an object 6 or more feet from your finger. Then without moving your arms, shift your head left and right. The apparent position of the object will move away from the pointing finger.

The pix below demonstrate the effects when a camera is involved.

[ATTACH]6683[/ATTACH]
This was taken from just to the left of 'dead on' the bandsaw blade.
Notice the left face of the blade is visible.
Notice the blade appears to be close to the right end of the bearing.
Since the camera's flash is in line with the lens, all shadows are directly behind any object and therefore not visible in the pix. However you can see a reflection of the flash off the left face of the blade to the left of the blade.

[ATTACH]6684[/ATTACH]
This was taken from just to the right of 'dead on' the bandsaw blade.
Notice the Right face of the blade is visible.
Notice the blade appears to be closer to the left end of the bearing.
Although not as apparent as in the first pix, a reflection is to the right of the blade.

[ATTACH]6685[/ATTACH]
This was taken quite close to 'dead on'.
Notice neither side of the blade is visible.
Notice the blade appears nearer to the center of the bearing than either the right or left viewpoint.

The flash is above the lens so those objects higher or lower than the center of the pix do have a visible shadow(none to the left or right).

from Greenhornet

Posted: Mon Nov 30, 2009 12:01 pm
by greenhornet
JPG - I received your phone message this a.m. Until now, I was unable to retrieve my messages. I called you back this a.m. around 11 but reached a computer/fax/modem sound. Please try to reach me again. I'm a franchisee of Liberty Tax Service and am in my store now and will be here for a couple of hours yet to take care of some business. The number here is 757-850-0840 if you want to call me here. Or my home number is 757-825-1254. My cell again is 757-254-1071.

Thank you and I look forward to talking with you.

Ray

maintenance issues

Posted: Thu Dec 03, 2009 11:08 am
by greenhornet
JPG - It was great to talk with you the other evening. I've further lubricated the bottom shaft/sheave assbly, and I've been able to slide that sheave along the shaft! I'm still waiting for the speed control handle from SS when I'll do the other stuff you suggested I do, ie, high speed alignment. I'll get back to you on those things later.

Thanks

Ray

Maintenance on 510

Posted: Fri Dec 04, 2009 9:53 pm
by greenhornet
JPG - Well, I put my new SS speed control handle on today, after carefully turning the speed down to slow. When I turned on the SS and turned it up to high speed, boy, was it smooth and easy! Almost like brand new! I'm telling you it was great! When I get my new quadrant assbly, I'll probably have to do another high speed alignment, but that's OK because I know about it now. Any way, thank you for all of your help!

I'm working on a bedside table now. I plan on making two of them for Christmas gifts - one for my wife, and one for our pastor. I'm going to pick up some more walnut tomorrow and will make another table with that stock for the little old lady who's giving me the walnut.

Hope to talk to you again soon. My email addy is raynations1@aol.com.

Between now and the first of the year, I'm going to tackle at least one more project. After the first, I'm busy with taxes. I own a Liberty Tax Service franchise here and will be up to my eyeballs with that until April 15th, at least.

Take care and thanks again.

Peace

Ray