LensAlign Pro Plus Calibration System...my experience

Bfromaz wrote in post #10501997
I don't get the whole pay a chunk of cash for something that is easy to do free. I just recieved my 7D last week. Here is how I plan on doing it.

2 Tripods, 1 2 foot dowel. Small piece of cardboard. 25' lenth of string. 2' lenth of string. Fishing wieght. Printed calibration target.

Dowel taped to top of tripod 1. String from dowel to hanging cardboard with target on it ( fishing wieght to keep it down ). Gravity will keep it straight. Second string loosly tied from target to tripod leg to keep it even ( could use other materials for this ).

Measure target center to ground. Mount camera on second tripod and position camera the same distance to ground. 25' string to put a 25' distance between the 2. Take 20 shots pick the accurate focus point based on different MA settings.

Save $200.00 plus dollars. Buy a new toy that I will use more than once.

Bfromaz

sounds all good in theory, I suspect you'll lose your mind trying to pick which shot is better than the others...

Is I see it, the microadjustment is all about having a good contrasty target, and being able to easily pick where the actual focus-plane is in order to adjust accordingly. The LA system looks to provide both. There is always more than one way to slice your bread however...

Probably a stupid question but why is it recommended to use a wired shutter release? Why not just a cheapy ebay wireless remote?

ZCphoto wrote in post #10502901
Probably a stupid question but why is it recommended to use a wired shutter release? Why not just a cheapy ebay wireless remote?

I don't think that matters. What matters is not touching the camera shutter button and inducing vibration.

joeseph wrote in post #10502696
sounds all good in theory, I suspect you'll lose your mind trying to pick which shot is better than the others...

Is I see it, the microadjustment is all about having a good contrasty target, and being able to easily pick where the actual focus-plane is in order to adjust accordingly. The LA system looks to provide both. There is always more than one way to slice your bread however...

Actually the out of focus shots will be the key element and those should be easy to spot. A 400mm at 25' has a .24 dop .12 either way. Say 2 is out of focus and 3, 4, 5 are in and 6 is out... 4 is then the magic number. If I get to where I need to pick between 2 even numbers I just increase the distance and run it again till I get enough separation to chose 1.

Gravity to ensure alignment. Measurement and math to ensure accuracy. Personally I think its going to be much easier to align with accuracy using the OOF shots then to guess based on in focus shots and the ops $200 system.

IMHO

Bfromaz

Can you post a shot of your set up and some of the photos used to determine the MA number after testing? I'd like to see it and the results.

Thanks

Bfromaz wrote in post #10503342
Actually the out of focus shots will be the key element and those should be easy to spot. A 400mm at 25' has a .24 dop .12 either way. Say 2 is out of focus and 3, 4, 5 are in and 6 is out... 4 is then the magic number. If I get to where I need to pick between 2 even numbers I just increase the distance and run it again till I get enough separation to chose 1.

Gravity to ensure alignment. Measurement and math to ensure accuracy. Personally I think its going to be much easier to align with accuracy using the OOF shots then to guess based on in focus shots and the ops $200 system.

IMHO

Bfromaz

I just ordered the light version.. I will see how consistent the results are..

Methodical wrote in post #10503806
Can you post a shot of your set up and some of the photos used to determine the MA number after testing? I'd like to see it and the results.

Thanks

This is all theory at this point. I'm going to try it this weekend. After seeing all these calibration threads I figured I would try something different. Using out of focus shots to determin accurate focus seemed the way to go. I think the only real variable will be the distances I will have to use and then compensate with a dop calculator.

Bfromaz

I have a question.

In my experience, the amount of correction needed depends on the distance between the camera and the target. It would be nice if the microadjust number stayed at a constant value regardless of test distance but this doesn't seem to be the case.

My 50mm f/1.4 is spot on at 2 feet, but front focuses a few inches at 20ft. How do you deal with this?

Thanks,
Jeff

Methodical wrote in post #10503806
Can you post a shot of your set up and some of the photos used to determine the MA number after testing? I'd like to see it and the results.

Thanks

I didn't bother with getting exact alignments - after all, the DoF at 50x FL and f2.8 is about 1 foot, so if the target isn't exactly parallel to the sensor it won't matter one jot.

Here's some of the images from doing the simple, cheap (about 50p) version of MFA. They are 100% crops of the central portion of the AF test chart. To do the comparisons I use Lightroom's 'Compare' tool to find the sharpest image - like this. I got the same results doing it again a few days later. At around 50,000% cheaper than the LA system I'm quite satisfied.

Determine which distance you shoot most with that lens and microadjust based on that. But I mean, 50mm needs like 4ft or something away from target to do 25x... I would just base is on that, personally. They say to avoid being close to MFD for calibration.

BTW, I ordered the little emulator or whatever they call it, the little slide-targets to show distance and microadjust values on the target (my PRO did not come with it and I wanted it)... I contacted the company and it only cost me $4.85 shipped to my door and the quality is awesome (for what it is). The magnet 'buttons' are smooth and easy to use, and make the whole adjustment process very easy. I can shoot 20+ images at different MA values and see what they all are right away without having to check back in-camera and all that. Really makes my life easier. I did the 24-105 last night with (4) images at each value... -4, -2, 0, 2, 4 at both 24mm and 105mm... Did that all at the same time, imported to PS and ran the emboss filter within minutes But anyway, I like this little key for making the process easier. Clearly shows on any image exactly what values are for quick sorting.

hollis_f wrote in post #10504431
Here's some of the images from doing the simple, cheap (about 50p) version of MFA. They are 100% crops of the central portion of the AF test chart. I got the same results doing it again a few days later. At around 50,000% cheaper than the LA system I'm quite satisfied.

This is exactly what I did to MA my lenses prior to the Lens Align... I had a target setup and basically took shots at different MA values until I got the sharpest with the best resolution. However, as confirmed by my Lens Align, this did not work out to be accurate for me on my 300L or my 135L/300L with the 1.4x TC. The values changed quite a bit and I really slaved over doing it right the first time with my own method.

Not saying it did not get me in the ballpark or anything, but for one reason or another it was not 100% accurate.

Either way, many methods will work... Some are easier than others.

Invertalon wrote in post #10504452
this did not work out to be accurate for me on my 300L or my 135L/300L with the 1.4x TC. The values changed quite a bit and I really slaved over doing it right the first time with my own method.

Hmmm, strange. With my 300 and a 1.4x TC changing the MFA value had little effect on the focus. A setting of +2, +7 and +12 all looked perfect.

Not sure, I just MA to what looks best

hollis_f wrote in post #10504743
Hmmm, strange. With my 300 and a 1.4x TC changing the MFA value had little effect on the focus. A setting of +2, +7 and +12 all looked perfect.

I agree... say you have a 400mm 5.6 shooting at 100'. That gives you 4' of in focus area. Even if your off a bit the results will be great.

I think it becomes a bit more critical with smaller lenses that have a much smaller dop.

Bfromaz

Found a cool way to lens align... looks promising.

http://www.birdphotogr​aphers.net …AF-microadjustment-tricks

Bfromaz