planepics Loc: St. Louis burbs, but originally Chicago burbs

This is the first pic I've taken with a LensAlign focus target. I got it as a package deal with my lens (150-600). I can't tell quite where it's focusing. Do I need more light on the target? I was using my 17-50 lens as a test subject on a tripod (ball head) and shot with a 2-second delay to try to avoid shakes. My tripod is on a carpeted floor. Should I have used my wireless remote? I've never attempted to microadjust a lens/body combo. The target is on the table because when I screwed it onto a footed monopod I found that the bushing was cockeyed and wouldn't mount level :( Oops...just realized I didn't attach the large focus target in front of the alignment part. Does it matter? I was more concerned with the rule on the right side.

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Tomfl101 Loc: Mount Airy, MD

Your lens appears to be focusing exactly right as I see it. The zero is sharp along side of the Lens Align Target. If the lens was off a number in front or behind the target would be sharp.

tinplater Loc: Scottsdale, AZ

Looks right on, however you are so far away from the target, the depth of field is so great that it may make it difficult to identify the exact focus spot.
Remember geometry is key. You must have the lens perfectly horizontal and vertically aligned. The center of your target must be aligned exactly with the center of the lens barrel. I found a laser pointer very helpful in getting everything lined up correctly. If a lens is perfectly centered the horizontal lines going up the slope should be equally in or out of focus on each side of the zero line. The target also must be absolutely at 90 degrees to the lens horizontal axis. It is quite tedious to set this up correctly if you want results that are meaningful.

One last thing, it is readily apparent that your target is not centered on the lens and sensor (it is clearly off to the right side.) Get closer, align carefully.

planepics Loc: St. Louis burbs, but originally Chicago burbs

I just took a new pic...with the real target installed. On the first pic, it seems to me that the numbers going down are a bit blurrier (36 on the bottom (front) looks softer than the 36 on the top). At least to me it does. Would that mean I'd have to do a plus or a minus adjustment if it was focusing farther?? I probably jostled the target a bit when installing the other target.

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planepics Loc: St. Louis burbs, but originally Chicago burbs

I'll try it again. Maybe outside on the porch where I have more room (and light) and a concrete surface. The instructions suggested using the target on a pan-and-tilt head, but I don't own one. I could try aligning from the back...perhaps I'd get closer to parallel that way. I can't use the target on my new monopod because the mounting hole on the target plate is messed up. I already wrote to the manufacturer, but I probably wont here back until Monday.

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dave.speeking Loc: Brooklyn OH

To do the focus, you must be directly in front of the white card.
At the same level as the Zero. Focus on the zero.

The left side of the setup is for something else.

If all else fails, check the instructions.

Muddyvalley Loc: McMinnville, Oregon

I checked your metadata.
You are shooting on auto. It shot it @ f/8 and 1/8sec shutter speed. Is that as open as the lens will go?
Try manual, a higher shutter speed, and as open as the lens will go. The widest aperture.
As mentioned, at the same height, and look into the small target so that the 'tunnel' is straight.

anotherview Loc: California

Try mirror lockup as well to avoid all but the tiniest camera movement.

amfoto1 Loc: San Jose, Calif. USA

The 2-second delay probably served the same purpose as a wireless remote. Either mean that you aren't touching the camera during exposure, possibly causing accidental "shake blur".

I'd recommend using "Mirror Lockup", if your camera has it, too. Alternatively, "Live View" can be used. These are to reduce internal camera vibrations, caused by "mirror slap" that can cause some image softness at longer shutter speeds, such as you were using. You also could have set a custom white balance and dialed in some + Exposure Compensation to brighten the image a bit.

None of this directly relates to the focus test you're doing. These precautions and settings merely make for a better image that might make it easier to tell where the lens is focusing.

The primary problem with your test shot is that you stopped the lens down to f/8. Stopping it down that way has made DoF deep enough to cover almost the entire angled portion of the Lens Align target. If you'd used it wide open instead, depth of field would have been a lot shallower, and you'd have better info to work with because the point of focus would be more apparent in the image. Unless you shoot in a brighter location, to offset a three-stop smaller aperture you'll need to use a slower shutter speed and/or a higher ISO. But those shouldn't be any problem.

I see that this sample shot was done at the 50mm end of the lens' zoom range. The 17mm end of the range will be more difficult, since even at f/2.8 it will naturally have greater DoF. In that case, you'll need to move closer, too. There's probably info with the instructions recommending distance to the target for different focal lengths. But, if not, most I've seen have recommended 50X the focal length....

At the 50mm end of the range: 50mm x 50 = 2500mm. For the metrically challenged: 2500mm / 25.4 = 98 inches... or just over 8 feet.

At the 17mm end, the same formula shows: 17mm x 50 = 850mm. 850mm / 25.4 = 33 inches... or about 3 feet.

planepics Loc: St. Louis burbs, but originally Chicago burbs

The aperture might be the problem...didn't think about that. The lens is a 17-50 f/2.8. If I can get this lens dialed in I'll try my macro lens and then my new bazooka.

planepics Loc: St. Louis burbs, but originally Chicago burbs

I don't think I can lock up the mirror on my Sony a77. I will look at the manual to see if I can or not.

planepics Loc: St. Louis burbs, but originally Chicago burbs

the instructions on the site said 25x the focal length (49.2 inches...I might have been off an inch. I need to help my dad for a while...I'll take some new pics later. At f/2.8.

amfoto1 Loc: San Jose, Calif. USA

Good point! I didn't notice what camera you're using. The a77 is a mirrorless camera, isn't it? Hence no mirror to lockup!

HOWEVER, I also think that doing the focus accuracy test is a waste of your time.

Check to confirm this, but I believe your mirrorless camera focuses using sensors built right into the image sensor itself and on the same plane as the image sensor. As such, there's no need for lens focus calibration. Nor is there any means of doing it and it can't get out of calibration. Even if the lens itself were to lose calibration for some reason it won't effect your images, because focus is always being checked and maximized by the camera right at its image plane.

This is different from autofocus SLRs and DSLRs (i.e. "reflex" or "mirror" cameras), where the phase detection focus sensors are separate from the image sensor. In those it's possible for the AF sensors and image sensor to be slightly out of sync with each other. For that reason, they require "focus calibration"... Mirrorless cameras don't.

So.... unless the a77 is somehow different from other mirrorless cameras or unless you also use some DSLRs or autofocus film SLRs... you can simply put away and forget about that focus target or sell it or give it to someone who can use it.

UPDATE: I just Googled the a77 and see that it actually is NOT a mirrorless camera. It uses a fixed, translucent mirror (can't be flipped up or moved out of the way with Live View, but also there's no chance of "mirror slap" since it doesn't move). AND... judging from some online discussions about it, apparently the a77 does have separate AF sensors and DOES have a micro focus adjustment feature.

So I guess you'll have use for that test target after all!

SonyA580 Loc: FL in the winter & MN in the summer

[quote=Muddyvalley]I checked your metadata.
You are shooting on auto. It shot it @ f/8 and 1/8sec shutter speed. Is that as open as the lens will go?
Try manual, a higher shutter speed, and as open as the lens will go. The widest aperture.

I also checked the EXIF data and Muddyvalley is correct; the lens should be wide open when doing this test.
Shooting at f/8 won't give you the best results. It would also help if you could get closer so that the target fills the entire screen. That would make it easier to distinguish between in and out of focus parts of the image.

planepics Loc: St. Louis burbs, but originally Chicago burbs

I already found where on the menu the microadjust settings are. I think what I'll try is take the stud out of my footed monopod, carefully set the target on top of the base, go outside and re-set up...after I play with the bazooka. So far I've only taken one test pic with it. Some neighbor horses from about 80-100 yds away, handheld. Not sure offhand what the SS was. I saw a hawk or some other bird circling a few minutes ago. I'll see if I can shoot him at full mag (600mm).