Lens Align

[Lowell Goudge]

this just goes to prove what I have thought all along. the single plane focusing charts are all a joke.

give the camera a flat surface to focus on, and the sloping ruler away from that focus point to measure the error.

Slope is not relevant all you need to do is make small adjustments to determine what your own scale means in terms of the adjustment factor.

The only issue I see is that off the centerline focus could be different any way, since it would require the lens to be a flat field lens in order to be in focus off the centerline

[VaughnA]

Originally Posted by Lowell Goudge

this just goes to prove what I have thought all along. the single plane focusing charts are all a joke.

give the camera a flat surface to focus on, and the sloping ruler away from that focus point to measure the error.

Slope is not relevant all you need to do is make small adjustments to determine what your own scale means in terms of the adjustment factor.

The only issue I see is that off the centerline focus could be different any way, since it would require the lens to be a flat field lens in order to be in focus off the centerline

THis system makes a LOT more sense than some of the others. I'm going to try this system out soon.

I'll just have to dig out my campy box. I've got both, I'm from a mixed family, Campy,Shimano, SRAM.

[WheresWaldo]

Originally Posted by Lowell Goudge

this just goes to prove what I have thought all along. the single plane focusing charts are all a joke.

give the camera a flat surface to focus on, and the sloping ruler away from that focus point to measure the error.

Slope is not relevant all you need to do is make small adjustments to determine what your own scale means in terms of the adjustment factor.

The only issue I see is that off the centerline focus could be different any way, since it would require the lens to be a flat field lens in order to be in focus off the centerline

LG, I am not so sure that the amount it is off the centerline is really of any significance, we are talking a degree or two is all. I also agree that the actual angle is not relevant as long as it is readily obvious in the resulting photos.

I also use the same setup to determine if replacement focusing screens accurately focus using manual lenses. It is very easy to use the micro-prism or split image to precisely focus on the box edge then determine if the manual focus is accurate.

Originally Posted by VaughnA

THis system makes a LOT more sense than some of the others. I'm going to try this system out soon.

I'll just have to dig out my campy box. I've got both, I'm from a mixed family, Campy,Shimano, SRAM.

My first attempt was using a SRAM Red Powerdome box, it just didn't seem right.

[tlwyse]

Originally Posted by Lowell Goudge

this just goes to prove what I have thought all along. the single plane focusing charts are all a joke.

give the camera a flat surface to focus on, and the sloping ruler away from that focus point to measure the error.

Slope is not relevant all you need to do is make small adjustments to determine what your own scale means in terms of the adjustment factor.

Which is EXACTLY how the LensAlign tool works....you're focusing on a flat vertical surface that, if you follow the directions, is perfectly parallel to your lens and you then evaluate focus on the ruler.

I'm all for these home-made solutions but you have to consider that the LensAlign instrument, even with the Long Ruler Kit, is less than HALF the cost of any decent single lens. Cheap insurance if you ask me and not worth the risk of trusting a home-grown solution to one of the most important aspects of your photography work. But that's just me.

Regards,
Terry

[pingflood]

I took a different approach to microadjusting on my 50D... I just pick a target at an appropriate distance, let the camera autofocus, then switch to live view, 10x magnification, and see if any amount of tweaking either front or back will improve the focus.

[creampuff]

Lens alignment charts? Watch this video...

YouTube - lightenupandshoot.blogspot.com - pixel peepers episode 2

[Eaglerapids]

Originally Posted by creampuff

Lens alignment charts? Watch this video...

YouTube - lightenupandshoot.blogspot.com - pixel peepers episode 2

ROTFLMAO!
That was pretty good creampuff:-).

[Class A]

Originally Posted by creampuff

Watch this video...

How can they keep a straight face?

Time to plug my AF adjustment hints again.

BTW, I did focus bracketing on a real subject and was happy ever since. All my portrait shots since then came out gloriously, with the focus on the eyelashes exactly where I wanted it to be.