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12-11-2012, 01:50 PM   #1
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Front and Back focusing updated charts for free.

Hi Photographer friends,

Do you have front or back focusing problems with some of your lenses or DSLR? You could spent in excess of One hundred dollars to get a manufactured lens aligning devices, or get mine for free. It does the same job and it cost nothing.

Why would I give it away? I love photography and I made some great cyber friends through my blogsite. It's my way to contribute a little, and help up and coming photographers. It can help Advanced and Pro Photographers as well.

For almost six years, my AF charts have been downloaded all over the world. The charts are downloaded on an average of five hundred times everyday. It was originally designed for the Pentax K20D, but I updated the charts by deleting any camera specific instructions, and by revising images and some of the instructions. I believe it is more user friendly than before. You be the judge. The charts (3) are now all inclusive in one downloadable package and are for every brands of DSLR cameras such as Pentax, Nikon, Canon, Sony, Olympus, and all other brands that have the capability of adjusting the AF settings of each of your lenses. Let your friends, that use other brand of camera than yours, know about the charts.

Download the Charts here right now.
http://www.k10dbook.com/newchart.pdf

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12-11-2012, 01:59 PM   #2
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I recommend these!
Worked well for me after having variable results with other charts. The size of the chart for given focal length and focus distance is important.
12-11-2012, 02:10 PM   #3
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Thanks Yvon. I was feeling my k-5 needed a calibration refresh after shooting a birthday the other night, now a new chart to play with.
12-11-2012, 03:47 PM   #4
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This looks great! Much better than using the text on a sheet of paper that I was using before.

Thanks for posting this.

12-11-2012, 03:55 PM   #5
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QuoteOriginally posted by k10dbook Quote
Hi Photographer friends,

Do you have front or back focusing problems with some of your lenses or DSLR? You could spent in excess of One hundred dollars to get a manufactured lens aligning devices, or get mine for free. It does the same job and it cost nothing.

Why would I give it away? I love photography and I made some great cyber friends through my blogsite. It's my way to contribute a little, and help up and coming photographers. It can help Advanced and Pro Photographers as well.

For almost six years, my AF charts have been downloaded all over the world. The charts are downloaded on an average of five hundred times everyday. It was originally designed for the Pentax K20D, but I updated the charts by deleting any camera specific instructions, and by revising images and some of the instructions. I believe it is more user friendly than before. You be the judge. The charts (3) are now all inclusive in one downloadable package and are for every brands of DSLR cameras such as Pentax, Nikon, Canon, Sony, Olympus, and all other brands that have the capability of adjusting the AF settings of each of your lenses. Let your friends, that use other brand of camera than yours, know about the charts.

Download the Charts here right now.
http://www.k10dbook.com/newchart.pdf
Thank You!
12-11-2012, 05:12 PM   #6
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Hmm.

Your instructions suggest that one should do the calibration at effectively the closest focusing distance of the lens. This may not be altogether a good idea
12-11-2012, 06:08 PM   #7
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QuoteOriginally posted by kh1234567890 Quote
Hmm.

Your instructions suggest that one should do the calibration at effectively the closest focusing distance of the lens. This may not be altogether a good idea
A close focusing distance with the lens at it's maximum aperture is where a lens is most vulnerable. If you are using zoom lenses, you actually have to calibrate at the zoomed focal length chosen. As you get farther from your subject, a one or two inch front or back focusing will not be very noticeable. Also remember that most lenses have a sweet spot witch is usually about two stops down from the maximum aperture and that the depth of field will be wider. It is my experience that calibrating a lens at the closest focusing distance and at the maximum aperture gives more accurate results.
12-16-2012, 02:43 AM   #8
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QuoteOriginally posted by k10dbook Quote
A close focusing distance with the lens at it's maximum aperture is where a lens is most vulnerable.
Yes, but if you calibrate with these parameters, you may introduce problems at other settings.

My recommendation is to calibrate with parameters that are typical for how you use a particular lens. My AF adjustment hints contain some more tips.

12-17-2012, 04:31 PM   #9
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QuoteOriginally posted by Class A Quote
Yes, but if you calibrate with these parameters, you may introduce problems at other settings.

, My recommendation is to calibrate with parameters that are typical for how you use a particular lens. My AF adjustment hints contain some more tips.
Class A,

Unless you constantly shoot the same subject with the same lens, in the same conditions, at the same distance, with the same lighting, it really doesn't matter if the edges are not calibrated as mentioned in your hints. Photography is mostly about opportunities in catching that special moment in time. If you can predict what you will shoot at the exact time and conditions in the future, that would be the solution. However, this won't happen on this planet.

If your lens is calibrated at the closest distance with the maximum aperture, surely you can take a great clear image at a greater distance with a smaller aperture. Furthermore, in this digital age, you can see what you have just shot...adjust accordingly until you get what is acceptable. You may still miss stat special moment in time, but as you get used to your lenses, you'll become a champion at it.

Focusing charts, regardless of which one you use, will not give repeatable results for zoom lenses. It really only works for prime lenses or at a pre-determined focal length on a telephoto.

The best advice; yes, calibrate your lenses if you really need to, but you will become a better photographer by taking a lot of pictures and get intimately knowledgeable with all of your equipment. Stop measurbating and go shoot pictures.

This response is in pure friendship, I do not put down any of the charts out there.
12-17-2012, 08:56 PM   #10
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QuoteOriginally posted by k10dbook Quote
Unless you constantly shoot the same subject with the same lens, in the same conditions, at the same distance, with the same lighting, it really doesn't matter if the edges are not calibrated as mentioned in your hints.
You apparently misunderstood that point. Your chart design is not ideal in that the read out location is quite a bit away from the focus location. Lenses with pronounced field curvature will not receive an optimal adjustment, in the sense that the outer areas will be optimally sharp, but not the point you focused on.

QuoteOriginally posted by k10dbook Quote
If your lens is calibrated at the closest distance with the maximum aperture, surely you can take a great clear image at a greater distance with a smaller aperture.
Unfortunately, your "surely" is not warranted. There is the phenomenon of "focus shift" and spherical aberrations that influence AF and AF behaviour can vary with focusing distance.

QuoteOriginally posted by k10dbook Quote
Stop measurbating and go shoot pictures.
I haven't used a focusing chart in years, so I'm not sure what your audience is here.

Last edited by Class A; 12-18-2012 at 02:00 AM.
12-17-2012, 09:47 PM   #11
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sigh...
12-17-2012, 10:55 PM   #12
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Take pictures. That's how you get better at it.
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