planepics
Loc: St. Louis burbs, but originally Chicago burbs
I just got my new base for the LensAlign and tried it out - the first one wouldn't screw into the stud straight. I think I may have jostled the tripod a tiny bit while attaching the focus plate, but I don't think it made much of a difference (I hope). The camera tripod and the footed monopod were on a carpeted floor. I was using my macro lens and it appears to be front-focusing. Do I apply a + or a - correction and re-shoot? (or did I screw the pooch and have to start over again aligning the lens)? Shot was taken using my 105mm macro lens on f/2.8.
I have a similar target - the DataColor SpyderLensCal. It has a base that allow me to just put it on a table. I roll up a small towel to use as a rest for my camera also on the table.
If the numbers on the scale in front the zero (closest to you) are in best focus, you need to enter negative (-) compensation in your camera AF fine tuning. That's how it is with my Nikons. Sony is probably the same way.
Looks to me like it is back focusing. Look at your camera AF micro focus menu and see how to move the focus plane forward. This is explained on-screen in your camera, if micro focus is available; not all cameras have this function.
JBruce wrote:
Looks to me like it is back focusing. Look at your camera AF micro focus menu and see how to move the focus plane forward. This is explained on-screen in your camera, if micro focus is available; not all cameras have this function.
Compare the numeral "6" and it looks like the rear "6" is a bit sharper than the front one. I think that's "back focus." Personally for testing I prefer to be on a solid surface rather than carpet but that wont matter for front/back focus issues so much.
TriX
Loc: Raleigh, NC
Appears to be back focusing to me (i’m Focusing on the sharpness of the concentric eclipses rather than the numerals). I will just add two things. First, from my experience, I wouldn’t be surprised if a macro lens showed somewhat different adjustment for macro work at close focusing distances as opposed to the longer distance you’re using. Second, the subjective nature of trying to determine the sharpest point on the lens align and the appropriate correction is what drove me to move to Riekan’s FoCal system.
Yeah, it's definitely slightly back focused.... NOT front-focused.
Consult your camera manual for info how to adjust.... can't say whether - or + is needed, it may be different depending upon the system.
How far away from your camera was the target set up? Assuming 25X focal length that some target manufacturers recommend, it should be about pprox. 8 or 9 feet, based upon a 105mm focal length.
I don't know if that's correct for a macro lens, though... which are designed for close focus instead of "normal, non-macro" distances. If it were me, I'd do the adjustment per the instructions (whatever they may be.... 25X focal length or whatever). Keep the camera on the tripod, use mirror lockup if possible, use a shutter release (it might help, too, to set a custom white balance and increase exposure a bit... so your image is as clear as possible). Take the shot using either a remote release or the camera's self-time, so that you aren't touching the camera while the shot is being taken.
Without removing the camera from the tripod or moving the target, make the adjustments... Re-focus, then repeat the test shot and see if your adjustment fixed the problem. This will tell you right away if you made the adjustment correctly.
Ideally once you have it better dialed in you should take a number of shots, perhaps a dozen, re-focusing between each, to check the repeatability of the system too.
Once satisfied with the adjustment, with a macro lens I'd also check it at a much closer distance, just to be sure that wasn't screwed up in the process of tweaking the focus at a distance farther away than the lens will normally be used. It would be different if it were a portrait lens, which is more likely to be used at distances similar to what you seem to be using for this test.
planepics, CO,JBruce,Don the second son, Trix,amfoto1, - - - - sorry, I know this is off topic but I have been wondering about these tests for awhile and I am completely without knowledge of where to look for info about them, or what you do to your lens after getting results from a test. Any link to information about this testing process would really be appreciated. Again, I am sorry for putting this question here, but it looks to me like you are a group of folks who know what is all about.
planepics wrote:
I just got my new base for the LensAlign and tried it out - the first one wouldn't screw into the stud straight. I think I may have jostled the tripod a tiny bit while attaching the focus plate, but I don't think it made much of a difference (I hope). The camera tripod and the footed monopod were on a carpeted floor. I was using my macro lens and it appears to be front-focusing. Do I apply a + or a - correction and re-shoot? (or did I screw the pooch and have to start over again aligning the lens)? Shot was taken using my 105mm macro lens on f/2.8.
I just got my new base for the LensAlign and tried... (
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Why do you want to Auto a Macro lens anyway? Critical macro focusing should be done manually. Personally I also would never play with my camera's or lenses' focusing as there are all kinds of reasons lens-camera combinations act the way they do. I'd leave it to a repair professional, repair shop or manufacturer. Some of the "slack" or seemingly odd stops is intentional.
Sorry for changing the subject but can’t find how to start a new one.
On my EOS R under shutter count it just shows a 5. Does this mean: 5, 50 or 500, what?
planepics
Loc: St. Louis burbs, but originally Chicago burbs
lamiaceae wrote:
Why do you want to Auto a Macro lens anyway? Critical macro focusing should be done manually. Personally I also would never play with my camera's or lenses' focusing as there are all kinds of reasons lens-camera combinations act the way they do. I'd leave it to a repair professional, repair shop or manufacturer. Some of the "slack" or seemingly odd stops is intentional.
Usually when I hand-hold a macro lens, or any lens for that matter (which is probably most of the time since I don't generally carry my tripod) I tend to be pretty wobbly - I could use all the help I can get! Besides, lenses and cameras are manufactured separately with different standard depending on who makes it. It seems to me inevitable that a particular camera/lens combo will not always work perfectly together. I have 3 Tamron lenses and a Sigma and my camera is a first-generation Sony SLT (a77)...what's to guarantee that there are no discrepancies between each lens' optics and their interaction with the auto-focus system?
TriX
Loc: Raleigh, NC
vineyardman wrote:
Sorry for changing the subject but can’t find how to start a new one.
On my EOS R under shutter count it just shows a 5. Does this mean: 5, 50 or 500, what?
At the top of this page (or any other), choose “create a new topic” and just fill in the blanks.
AirWalter wrote:
planepics, CO,JBruce,Don the second son, Trix,amfoto1, - - - - sorry, I know this is off topic but I have been wondering about these tests for awhile and I am completely without knowledge of where to look for info about them, or what you do to your lens after getting results from a test. Any link to information about this testing process would really be appreciated. Again, I am sorry for putting this question here, but it looks to me like you are a group of folks who know what is all about.
Here's a link to the instructions for the target I use. It's the DataColor SpyderLensCal.
https://www.datacolor.com/wp-content/uploads/2016/08/SpyderLENSCAL-UserGuide-FINAL-EN.pdf
planepics
Loc: St. Louis burbs, but originally Chicago burbs
Well, I screwed up again, but at least I learned SOMETHING...I set up my gear (using my new 150-600) out on the sidewalk but it was so bright I couldn't see the screen well enough to align the camera - it probably didn't help that I don't own a pan-and-tilt head - I gave up and took a few shots anyways at 0, +3 and -3. Minus 3 won by a bit, even though I forgot to attach the target tome after time!!! I guess I need to get a head cover or shade, buy an el-cheap-o PT head and use a partner to help align the target. It's still not perfect, but I still have just over a month until Oshkosh. I'll see if I can shoot a horse or a bird in the meantime (metaphorically, of course) I guess I could see if my local camera shop would do the calibration for a fee.
TriX
Loc: Raleigh, NC
planepics wrote:
Well, I screwed up again, but at least I learned SOMETHING...I set up my gear (using my new 150-600) out on the sidewalk but it was so bright I couldn't see the screen well enough to align the camera - it probably didn't help that I don't own a pan-and-tilt head - I gave up and took a few shots anyways at 0, +3 and -3. Minus 3 won by a bit, even though I forgot to attach the target tome after time!!! I guess I need to get a head cover or shade, buy an el-cheap-o PT head and use a partner to help align the target. It's still not perfect, but I still have just over a month until Oshkosh. I'll see if I can shoot a horse or a bird in the meantime (metaphorically, of course) I guess I could see if my local camera shop would do the calibration for a fee.
Well, I screwed up again, but at least I learned S... (
show quote)
Or you could by the Reikan FoCal system and calibrate for all your lenses accurately in perpetuity.
planepics
Loc: St. Louis burbs, but originally Chicago burbs
Here's one hand-held pic I took a few minutes ago in the backyard at 600mm with the new -3 adjustment. I might still play with it a bit, but SOOC it's not bad for a start.
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