I have a Canon 5D3 with a number of different lenses. I bought an inexpensive ($10) focusing card from Amazon, but don't feel like I really have it dialed in. Then I tried a ruler set to a 45 degree angle. After some of my adjustment attempts, the autofocus was worse.
Can anyone recommend a good tool and technique for determining where to set the micro-adjust? (I know how to set the adjustments in the camera.)
Thanks
If you want it done right, look at LensAlign MkII Focus Calibration System. Make sure you have the ability to bring the software / computer (laptop) to the camera on a tripod for tethered shooting. There's some useful comments on Amazon for a source of more info.
papa
Loc: Rio Dell, CA
I use Magic Lantern's AFMA and it works quite well automatically with all four of my lenses: Tokina 16-28, Tammies 24-70, 70-200, 150-600. Best part is it's free and has amazing tools on the menu. If you're not familiar, then you can bone up here;
https://www.magiclantern.fm/index.htm
Gene51
Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)
dandev wrote:
I have a Canon 5D3 with a number of different lenses. I bought an inexpensive ($10) focusing card from Amazon, but don't feel like I really have it dialed in. Then I tried a ruler set to a 45 degree angle. After some of my adjustment attempts, the autofocus was worse.
Can anyone recommend a good tool and technique for determining where to set the micro-adjust? (I know how to set the adjustments in the camera.)
Thanks
Since lens focus issues are complex and rarely linear in nature, there is a good likelihood that by adjusting for a particular distance and focal length, you will change the focus behavior at other distances and focal lengths. It is not unusual to have a lens front focus at distance, focus correctly at infinity, and back focus at 4 ft. When you apply in camera tuning, you are offsetting the entire focus system. So you if your lens is front focusing at 30 ft may get "perfect"focus at 30ft by dialing in an adjustment, but your lens will back focus even worse at 4 ft, and may not focus at infinity anymore.
In camera stuff is not a good way to resolve these issues. Better to let Canon work this out. There tools are far more accurate and granular in nature so they, not you, can really get it right. This AF Tune thing is a placebo, and a way for many people to make money off of something that is tantamount to a silver bullet or snake oil. Ask any tech and they will tell you the same thing.
If you are doing certain types of work that require a focus offset, or you are in the field and you need a quick fix because something got out of whack, it can work. But it is not intended as a permanent solution.
Ive never had the need to micro adjust any lens.
dandev wrote:
I have a Canon 5D3 with a number of different lenses. I bought an inexpensive ($10) focusing card from Amazon, but don't feel like I really have it dialed in. Then I tried a ruler set to a 45 degree angle. After some of my adjustment attempts, the autofocus was worse.
Can anyone recommend a good tool and technique for determining where to set the micro-adjust? (I know how to set the adjustments in the camera.)
Thanks
I use the quick and dirty 3-beer can method.
Get three identical cans with good details. Set them up on a diagonal with a 2-6 inch offset from each other facing the direction of the camera. The offset can be adjusted as needed depending on the focal length and aperture and desired precision. The left and right cans should have equal offset from the middle. Smaller apertures and focal lengths will require more offset and vice-versa. The spread distance of the cans can be adjusted for the coverage/distance from the camera. For lenses 300-400 mm I am generally 20-30 feet distance with the camera/lens.
With camera on tripod, ideally level and square with plane of the middle can, let the AF focus on the middle can. Review the shot magnified on your LCD. The middle can should appear the sharpest, the left can (having the furthest distance from the camera) should be less sharp. The right side can, being the closest, should also be less sharp than the middle and slightly less sharp than the left side (furthest) can. Adjust accordingly. For more precision, move the diagonal offsets closer.
As I said, this is low-tech quick and dirty/simple/cheap method - not - ultra precision, but it does work well for me and gives me good confidence regarding focus.
imagemeister wrote:
I use the quick and dirty 3-beer can method.
Awesome! Results are probably even better with five beer cans, maybe seven!
I don't actually drink much beer. Would it work with diet soda cans?
barbie.lewis wrote:
Awesome! Results are probably even better with five beer cans, maybe seven!
I don't actually drink much beer. Would it work with diet soda cans?
Whatever is available ....but they must all be the same ....
I usually set the cans on the truck lid of my car.
imagemeister wrote:
Whatever is available ....but they must all be the same ....
Great! Will give it a try!
I wonder if this would work with wine bottles?
:-))
quote=imagemeister]I use the quick and dirty 3-beer can method.
Get three identical cans with good details. Set them up on a diagonal with a 2-6 inch offset from each other facing the direction of the camera. The offset can be adjusted as needed depending on the focal length and aperture and desired precision. The left and right cans should have equal offset from the middle. Smaller apertures and focal lengths will require more offset and vice-versa. The spread distance of the cans can be adjusted for the coverage/distance from the camera. For lenses 300-400 mm I am generally 20-30 feet distance with the camera/lens.
With camera on tripod, ideally level and square with plane of the middle can, let the AF focus on the middle can. Review the shot magnified on your LCD. The middle can should appear the sharpest, the left can (having the furthest distance from the camera) should be less sharp. The right side can, being the closest, should also be less sharp than the middle and slightly less sharp than the left side (furthest) can. Adjust accordingly. For more precision, move the diagonal offsets closer.
As I said, this is low-tech quick and dirty/simple/cheap method - not - ultra precision, but it does work well for me and gives me good confidence regarding focus.
[/quote]
Interesting. Does it still work if you empty the cans first?
dandev wrote:
I have a Canon 5D3 with a number of different lenses. I bought an inexpensive ($10) focusing card from Amazon, but don't feel like I really have it dialed in. Then I tried a ruler set to a 45 degree angle. After some of my adjustment attempts, the autofocus was worse.
Can anyone recommend a good tool and technique for determining where to set the micro-adjust? (I know how to set the adjustments in the camera.)
Thanks
I was curious and just taped a newspaper at infinity on my pumphouse door.
Set camera on a tripod and started at 0 then the - numbers and then the + numbers.
I wrote each one in order.
Downloaded the photos and picked which looked best 0 in this case and figured my lenses are pretty good from the factory.
If you want to reply, then
register here. Registration is free and your account is created instantly, so you can post right away.