Re: k-3 fine focus adjustment
Paul via phone On Dec 23, 2013, at 2:57 AM, Jan van Wijk pen...@dfsee.com wrote: Hi Paul, On Sun, 22 Dec 2013 15:20:24 -0500 Paul Stenquist wrote: Highly complex targets with cool graphics work, but so does a simple system of lines with the center line readily identifiable. I made a chart in PhotoShop comprised of a series of lines about a centimeter apart. The target line in the center is thicker than the others. With the camera at a 45 degree angle to the chart, I autofocus on the center line with center spot selected for focus. This will work, as long as you can make sure the camera only 'sees' your target line, so the measurement lines must be far enough away from the 'target' line. Yes, and about a centimeter seems to be enough. I've used this chart with k3, k5, k7, and k20 and achieved accurate results. I do use the viewfinder to ensure alignment and take multiple shots. That said, I think I will open up some space around the center of the thick line. That is why I prefer to have those printed at the sides only, and have ONLY that target line near the center area in my viewfinder. The K3 is probably better at it, but I found it hard to focus exactly on a single small detail with the K10, K7 and K5, when other details are closeby ... Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Hi Alan, On Sun, 22 Dec 2013 07:14:36 +0200 Alan C wrote: Having read this thread, I can only conclude that either I am dof or there is some some trick to being successful with this procedure. Last week I decided to fine tune my identifiable lenses on the K7. I used Bob Atkins grid, set the lenses at their widest aperture worked as close as I could get. With each lens, I took shots at -10, -5, -2, 0 +2, +5 +10. Well, with all lenses, there is absolutely no difference between the shots. OK, so I figured it was because they are slow consumer lenses and decided to try it with my Super Tak 50/1.4 - same result. Hmm, not sure what Bob's grid looks like, but I have had good success with a PDF I found on the net somewhere, that is printed out with a laserprinter, and has a high-contrast horizontal dark line in the center as a focus target. It is only a few millimeters wide, and important, there is NOTHING above and below it to make sure it is really focussing on this line and nothing else. The line is perhaps 5 centimeters or 2 inches wide. To each side of this focussing target, there is a sort of 'ruler' that has various patterns but more importantly has a series of numbers with 0 in the middle, en going down to -20 or so and +20 on the other side. What I do to adjust focus for a lens is: - Put camera with lens on a tripod, and position it such that it 'sees' the piece of paper withy the target at an angle between 30 and 45 degrees, at a distance that is suitable for the lens, usually between 50 cm and perhaps 3 meters, depending on focal length. It is important to make sure the focusing target and a significant part of the 'ruler' area are in the frame, and large enough ... - Set the camera to use the 2-second delay (which also does a mirror-up on K7/K5/K3) - Set the lens to it maximum aperture, wide open (for minimum depth of field) - set the lens to infinity, then let if autofocus on the target line (using center, spot focus) - Take the shot, then use the review/display to judge focussing. (You COULD do this after downloading to the computer, but that takes too much time for me) - Look at the ruler, ENLARGED at least 8x, and pan over it to see if the focusing/fuzziness is distributed evenly around the ZERO mark (usually it is NOT) - When the area of best focus id BEFORE the target (front focusing), dial in a small negative value (like -3 or -4) for the correction (and I always use APPLY ONE, because I want to have specific correction per lens) - When best focus is BEHIND the target (BACK FOCUSSING), dial in a small postive value. - Repeat the test, and keep adjusting until the area that is the sharpest is centered around the ZERO marker. So I do NOT take a lot of shots in one go, then evaluate, I take one shot, evaluate on the back display, zooming the magnification and panning around the image/ruler, then decide on the correction to apply. A bit trial and error, but this is what has worked best/fastest for me on the K7, K5 and now the K3 ... For zoom lenses, I tend to use the longest focal length (has lowest depth of field) but depending on the lens, you could also use your 'most used' focal length. For macro I try to use a smaller subject distance, but that may require a smaller target and ruler, so a different, scaled, print-out. For extreme tele, you could even use an outside target, like a row of telephone poles, as long as you make sure the camera has a single edge/line like thing to focus on, with no distracting other things that are near that same distance. The important thing is, you HAVE to make sure the camera focuses on a small/narrow hight contrast edge or line, and nothing else, AND you need something WELL AWAY from the focusing point that will clearly show you where the actual plane of maximum sharpness is, so you can see if there is a front- or back-focusing problem to correct. Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
That’s pretty much how I do it, but I don’t use mirror lock up because I want to be looking through the view finder so I can be sure the center dot is right on my target line when the shutter opens. I made my own grid in PhotoShop. One slightly thicker rule in the middle, about 2mm in width a with a series of ten one mm lines positioned to either side of it, each about 1.5 cm apart. When lines two thrtee and four on each side of the sharp center line are equally out of focus, you know you’ve nailed it. On Dec 22, 2013, at 5:41 AM, Jan van Wijk pen...@dfsee.com wrote: Hi Alan, On Sun, 22 Dec 2013 07:14:36 +0200 Alan C wrote: Having read this thread, I can only conclude that either I am dof or there is some some trick to being successful with this procedure. Last week I decided to fine tune my identifiable lenses on the K7. I used Bob Atkins grid, set the lenses at their widest aperture worked as close as I could get. With each lens, I took shots at -10, -5, -2, 0 +2, +5 +10. Well, with all lenses, there is absolutely no difference between the shots. OK, so I figured it was because they are slow consumer lenses and decided to try it with my Super Tak 50/1.4 - same result. Hmm, not sure what Bob's grid looks like, but I have had good success with a PDF I found on the net somewhere, that is printed out with a laserprinter, and has a high-contrast horizontal dark line in the center as a focus target. It is only a few millimeters wide, and important, there is NOTHING above and below it to make sure it is really focussing on this line and nothing else. The line is perhaps 5 centimeters or 2 inches wide. To each side of this focussing target, there is a sort of 'ruler' that has various patterns but more importantly has a series of numbers with 0 in the middle, en going down to -20 or so and +20 on the other side. What I do to adjust focus for a lens is: - Put camera with lens on a tripod, and position it such that it 'sees' the piece of paper withy the target at an angle between 30 and 45 degrees, at a distance that is suitable for the lens, usually between 50 cm and perhaps 3 meters, depending on focal length. It is important to make sure the focusing target and a significant part of the 'ruler' area are in the frame, and large enough ... - Set the camera to use the 2-second delay (which also does a mirror-up on K7/K5/K3) - Set the lens to it maximum aperture, wide open (for minimum depth of field) - set the lens to infinity, then let if autofocus on the target line (using center, spot focus) - Take the shot, then use the review/display to judge focussing. (You COULD do this after downloading to the computer, but that takes too much time for me) - Look at the ruler, ENLARGED at least 8x, and pan over it to see if the focusing/fuzziness is distributed evenly around the ZERO mark (usually it is NOT) - When the area of best focus id BEFORE the target (front focusing), dial in a small negative value (like -3 or -4) for the correction (and I always use APPLY ONE, because I want to have specific correction per lens) - When best focus is BEHIND the target (BACK FOCUSSING), dial in a small postive value. - Repeat the test, and keep adjusting until the area that is the sharpest is centered around the ZERO marker. So I do NOT take a lot of shots in one go, then evaluate, I take one shot, evaluate on the back display, zooming the magnification and panning around the image/ruler, then decide on the correction to apply. A bit trial and error, but this is what has worked best/fastest for me on the K7, K5 and now the K3 ... For zoom lenses, I tend to use the longest focal length (has lowest depth of field) but depending on the lens, you could also use your 'most used' focal length. For macro I try to use a smaller subject distance, but that may require a smaller target and ruler, so a different, scaled, print-out. For extreme tele, you could even use an outside target, like a row of telephone poles, as long as you make sure the camera has a single edge/line like thing to focus on, with no distracting other things that are near that same distance. The important thing is, you HAVE to make sure the camera focuses on a small/narrow hight contrast edge or line, and nothing else, AND you need something WELL AWAY from the focusing point that will clearly show you where the actual plane of maximum sharpness is, so you can see if there is a front- or back-focusing problem to correct. Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net
Re: k-3 fine focus adjustment
Hi Jan Many thanks for the tutorial. I'm sure it will be of use to others too. This is the link for Bob Atkins test chart: http://bobatkins.com/photography/technical/lens_testing/reschart.zip It has plenty of grids, etc. but no ruler. I more or less did as you suggest but the chart was set at 90deg, not 45; coupled with the fact that I have only slow consumer lenses (Min apertures from 3.5 - apart from the Super Tak 50/1.4). At first I thought the range from -10 to +10 might be covered the DOF but shouldn't be with the Tak at f1.4. I'm still a bit perplexed but will try it again with a different chart (incorporating a ruler) or a row of bricks set up like dominos (at 45deg) see what happens. There is a lot of truth in Bill's comment that f8 is my friend if you only have slow lenses. Best regards, thanks for all your trouble. Alan C -Original Message- From: Jan van Wijk Sent: Sunday, December 22, 2013 12:41 PM To: Pentax-Discuss Mail List Subject: Re: k-3 fine focus adjustment Hi Alan, On Sun, 22 Dec 2013 07:14:36 +0200 Alan C wrote: Having read this thread, I can only conclude that either I am dof or there is some some trick to being successful with this procedure. Last week I decided to fine tune my identifiable lenses on the K7. I used Bob Atkins grid, set the lenses at their widest aperture worked as close as I could get. With each lens, I took shots at -10, -5, -2, 0 +2, +5 +10. Well, with all lenses, there is absolutely no difference between the shots. OK, so I figured it was because they are slow consumer lenses and decided to try it with my Super Tak 50/1.4 - same result. Hmm, not sure what Bob's grid looks like, but I have had good success with a PDF I found on the net somewhere, that is printed out with a laserprinter, and has a high-contrast horizontal dark line in the center as a focus target. It is only a few millimeters wide, and important, there is NOTHING above and below it to make sure it is really focussing on this line and nothing else. The line is perhaps 5 centimeters or 2 inches wide. To each side of this focussing target, there is a sort of 'ruler' that has various patterns but more importantly has a series of numbers with 0 in the middle, en going down to -20 or so and +20 on the other side. What I do to adjust focus for a lens is: - Put camera with lens on a tripod, and position it such that it 'sees' the piece of paper withy the target at an angle between 30 and 45 degrees, at a distance that is suitable for the lens, usually between 50 cm and perhaps 3 meters, depending on focal length. It is important to make sure the focusing target and a significant part of the 'ruler' area are in the frame, and large enough ... - Set the camera to use the 2-second delay (which also does a mirror-up on K7/K5/K3) - Set the lens to it maximum aperture, wide open (for minimum depth of field) - set the lens to infinity, then let if autofocus on the target line (using center, spot focus) - Take the shot, then use the review/display to judge focussing. (You COULD do this after downloading to the computer, but that takes too much time for me) - Look at the ruler, ENLARGED at least 8x, and pan over it to see if the focusing/fuzziness is distributed evenly around the ZERO mark (usually it is NOT) - When the area of best focus id BEFORE the target (front focusing), dial in a small negative value (like -3 or -4) for the correction (and I always use APPLY ONE, because I want to have specific correction per lens) - When best focus is BEHIND the target (BACK FOCUSSING), dial in a small postive value. - Repeat the test, and keep adjusting until the area that is the sharpest is centered around the ZERO marker. So I do NOT take a lot of shots in one go, then evaluate, I take one shot, evaluate on the back display, zooming the magnification and panning around the image/ruler, then decide on the correction to apply. A bit trial and error, but this is what has worked best/fastest for me on the K7, K5 and now the K3 ... For zoom lenses, I tend to use the longest focal length (has lowest depth of field) but depending on the lens, you could also use your 'most used' focal length. For macro I try to use a smaller subject distance, but that may require a smaller target and ruler, so a different, scaled, print-out. For extreme tele, you could even use an outside target, like a row of telephone poles, as long as you make sure the camera has a single edge/line like thing to focus on, with no distracting other things that are near that same distance. The important thing is, you HAVE to make sure the camera focuses on a small/narrow hight contrast edge or line, and nothing else, AND you need something WELL AWAY from the focusing point that will clearly show you where the actual plane of maximum sharpness is, so you can see if there is a front- or back-focusing problem to correct. Regards, JvW
Re: k-3 fine focus adjustment
Thanks, Paul. With all the expert advice, I'm bound to get it right now. Alan C -Original Message- From: Paul Stenquist Sent: Sunday, December 22, 2013 2:56 PM To: Pentax-Discuss Mail List Subject: Re: k-3 fine focus adjustment That’s pretty much how I do it, but I don’t use mirror lock up because I want to be looking through the view finder so I can be sure the center dot is right on my target line when the shutter opens. I made my own grid in PhotoShop. One slightly thicker rule in the middle, about 2mm in width a with a series of ten one mm lines positioned to either side of it, each about 1.5 cm apart. When lines two thrtee and four on each side of the sharp center line are equally out of focus, you know you’ve nailed it. On Dec 22, 2013, at 5:41 AM, Jan van Wijk pen...@dfsee.com wrote: Hi Alan, On Sun, 22 Dec 2013 07:14:36 +0200 Alan C wrote: Having read this thread, I can only conclude that either I am dof or there is some some trick to being successful with this procedure. Last week I decided to fine tune my identifiable lenses on the K7. I used Bob Atkins grid, set the lenses at their widest aperture worked as close as I could get. With each lens, I took shots at -10, -5, -2, 0 +2, +5 +10. Well, with all lenses, there is absolutely no difference between the shots. OK, so I figured it was because they are slow consumer lenses and decided to try it with my Super Tak 50/1.4 - same result. Hmm, not sure what Bob's grid looks like, but I have had good success with a PDF I found on the net somewhere, that is printed out with a laserprinter, and has a high-contrast horizontal dark line in the center as a focus target. It is only a few millimeters wide, and important, there is NOTHING above and below it to make sure it is really focussing on this line and nothing else. The line is perhaps 5 centimeters or 2 inches wide. To each side of this focussing target, there is a sort of 'ruler' that has various patterns but more importantly has a series of numbers with 0 in the middle, en going down to -20 or so and +20 on the other side. What I do to adjust focus for a lens is: - Put camera with lens on a tripod, and position it such that it 'sees' the piece of paper withy the target at an angle between 30 and 45 degrees, at a distance that is suitable for the lens, usually between 50 cm and perhaps 3 meters, depending on focal length. It is important to make sure the focusing target and a significant part of the 'ruler' area are in the frame, and large enough ... - Set the camera to use the 2-second delay (which also does a mirror-up on K7/K5/K3) - Set the lens to it maximum aperture, wide open (for minimum depth of field) - set the lens to infinity, then let if autofocus on the target line (using center, spot focus) - Take the shot, then use the review/display to judge focussing. (You COULD do this after downloading to the computer, but that takes too much time for me) - Look at the ruler, ENLARGED at least 8x, and pan over it to see if the focusing/fuzziness is distributed evenly around the ZERO mark (usually it is NOT) - When the area of best focus id BEFORE the target (front focusing), dial in a small negative value (like -3 or -4) for the correction (and I always use APPLY ONE, because I want to have specific correction per lens) - When best focus is BEHIND the target (BACK FOCUSSING), dial in a small postive value. - Repeat the test, and keep adjusting until the area that is the sharpest is centered around the ZERO marker. So I do NOT take a lot of shots in one go, then evaluate, I take one shot, evaluate on the back display, zooming the magnification and panning around the image/ruler, then decide on the correction to apply. A bit trial and error, but this is what has worked best/fastest for me on the K7, K5 and now the K3 ... For zoom lenses, I tend to use the longest focal length (has lowest depth of field) but depending on the lens, you could also use your 'most used' focal length. For macro I try to use a smaller subject distance, but that may require a smaller target and ruler, so a different, scaled, print-out. For extreme tele, you could even use an outside target, like a row of telephone poles, as long as you make sure the camera has a single edge/line like thing to focus on, with no distracting other things that are near that same distance. The important thing is, you HAVE to make sure the camera focuses on a small/narrow hight contrast edge or line, and nothing else, AND you need something WELL AWAY from the focusing point that will clearly show you where the actual plane of maximum sharpness is, so you can see if there is a front- or back-focusing problem to correct. Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo
Re: k-3 fine focus adjustment
Hi Alan, On Sun, 22 Dec 2013 15:07:24 +0200 Alan C wrote: Many thanks for the tutorial. I'm sure it will be of use to others too. This is the link for Bob Atkins test chart: You're welcome! http://bobatkins.com/photography/technical/lens_testing/reschart.zip It has plenty of grids, etc. but no ruler. Ok, that is a nice chart to test how good a lens resolves detail, but totally UNSUITABLE for focus adjust. This is an image about how a proper focus-adjust looks like, and how its used (it is the one I use): http://regex.info//i/JEF_024924.jpg This is another post about a slightly different one, with images: http://photography-on-the.net/forum/showthread.php?t=750736 And yet another one, on a pentax forum, including images too: http://pentaxdslrs.blogspot.nl/2012/01/front-or-back-focusing-problems-free.html As you can see, a contrasty focus TARGET is needed, and a sort of ruler, ANGLED to have its numbering or lines at different distances. But it should be well OUTSIDE the active focus-area of the camera (so use center-spot). Unfortunately I can't find the PDF for the one I am using now, but I do have one that is quite similar that you can download from my own website. It includes a description on how to use it, and you can simply print out the one (out of 20) page that is the chart itself, to use that. It is at: http://www.dfsee.com/download/focus-test-chart.PDF Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Highly complex targets with cool graphics work, but so does a simple system of lines with the center line readily identifiable. I made a chart in PhotoShop comprised of a series of lines about a centimeter apart. The target line in the center is thicker than the others. With the camera at a 45 degree angle to the chart, I autofocus on the center line with center spot selected for focus. This test is the FA 50/1.4 with my final +2 adjustment. Note the varying degrees of out of focus as the lines progress. The fourth line on each side is the first to be critically out of focus. Thus, the center is identifiable. I shot this at f2.5, as I've found that results with this lens wide open can be misleading. But most other lenses are tested wide open, particularly the DA* lenses, which are engineered to be optimum at wide aps. http://photo.net/photodb/photo?photo_id=17633001 Paul On Dec 22, 2013, at 2:32 PM, Jan van Wijk pen...@dfsee.com wrote: Hi Alan, On Sun, 22 Dec 2013 15:07:24 +0200 Alan C wrote: Many thanks for the tutorial. I'm sure it will be of use to others too. This is the link for Bob Atkins test chart: You're welcome! http://bobatkins.com/photography/technical/lens_testing/reschart.zip It has plenty of grids, etc. but no ruler. Ok, that is a nice chart to test how good a lens resolves detail, but totally UNSUITABLE for focus adjust. This is an image about how a proper focus-adjust looks like, and how its used (it is the one I use): http://regex.info//i/JEF_024924.jpg This is another post about a slightly different one, with images: http://photography-on-the.net/forum/showthread.php?t=750736 And yet another one, on a pentax forum, including images too: http://pentaxdslrs.blogspot.nl/2012/01/front-or-back-focusing-problems-free.html As you can see, a contrasty focus TARGET is needed, and a sort of ruler, ANGLED to have its numbering or lines at different distances. But it should be well OUTSIDE the active focus-area of the camera (so use center-spot). Unfortunately I can't find the PDF for the one I am using now, but I do have one that is quite similar that you can download from my own website. It includes a description on how to use it, and you can simply print out the one (out of 20) page that is the chart itself, to use that. It is at: http://www.dfsee.com/download/focus-test-chart.PDF Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Hi Paul, On Sun, 22 Dec 2013 15:20:24 -0500 Paul Stenquist wrote: Highly complex targets with cool graphics work, but so does a simple system of lines with the center line readily identifiable. I made a chart in PhotoShop comprised of a series of lines about a centimeter apart. The target line in the center is thicker than the others. With the camera at a 45 degree angle to the chart, I autofocus on the center line with center spot selected for focus. This will work, as long as you can make sure the camera only 'sees' your target line, so the measurement lines must be far enough away from the 'target' line. That is why I prefer to have those printed at the sides only, and have ONLY that target line near the center area in my viewfinder. The K3 is probably better at it, but I found it hard to focus exactly on a single small detail with the K10, K7 and K5, when other details are closeby ... Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Just out of curiosity, does the focus adjustment/fine focus adjustment work for NON-Pentax lenses (Tokina, Sigma, et al)? On 12/21/2013 12:08 PM, Paul Stenquist wrote: I finally got around to running some of my autofucus lenses through fine focus adjustment. The DA* 50-135 and DA* 60-250 were just about right on. Splitting hairs, I went for +1 on each. The FA 35/2 required +2 as did the FA 50/1.4. The our of the box focus was much closer than any other Pentax digital I've owned. Each generation was an improvement over the last. Paul -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Funny. I just got my k-5 back from CRIS recently and decided that AF was not where it was supposed to be. Had to go in debug mode and set it to -20(!!). It was originally at -10 when I first got the camera. Funny thing was I specifically asked CRIS to check the flange distance and mount. On their notes they claim they checked and calibrated it. I've learned not to rely on infinity stops with MF lenses since they get sloppy, so as long as I can make it confirm focus at infinity I can live with that. My original K-7 is dead on and the one I bought from Joe was at -7 before I dropped it. I'm going to get that one into debug mode soon and see if I can get the AF to focus properly again. On Sat, Dec 21, 2013 at 12:08 PM, Paul Stenquist pnstenqu...@comcast.net wrote: I finally got around to running some of my autofucus lenses through fine focus adjustment. The DA* 50-135 and DA* 60-250 were just about right on. Splitting hairs, I went for +1 on each. The FA 35/2 required +2 as did the FA 50/1.4. The our of the box focus was much closer than any other Pentax digital I've owned. Each generation was an improvement over the last. Paul -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
I'm pretty sure they do from reading user reports about having to adjust focus on third party lenses. On Sat, Dec 21, 2013 at 12:34 PM, John johnsess...@yahoo.com wrote: Just out of curiosity, does the focus adjustment/fine focus adjustment work for NON-Pentax lenses (Tokina, Sigma, et al)? On 12/21/2013 12:08 PM, Paul Stenquist wrote: I finally got around to running some of my autofucus lenses through fine focus adjustment. The DA* 50-135 and DA* 60-250 were just about right on. Splitting hairs, I went for +1 on each. The FA 35/2 required +2 as did the FA 50/1.4. The our of the box focus was much closer than any other Pentax digital I've owned. Each generation was an improvement over the last. Paul -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
On 12/21/2013 7:34 PM, John wrote: Just out of curiosity, does the focus adjustment/fine focus adjustment work for NON-Pentax lenses (Tokina, Sigma, et al)? Yes. The only problem could be if you have few 3rd party lenses that are recognized by the camera as the same one (as far as EXIF info goes). My understanding is that the lens-specific corrections are based on that id. I've Sigma 24-60/2.8 that requires some minor adjustment. Works perfectly well on either of my K-5's. Boris On 12/21/2013 12:08 PM, Paul Stenquist wrote: I finally got around to running some of my autofucus lenses through fine focus adjustment. The DA* 50-135 and DA* 60-250 were just about right on. Splitting hairs, I went for +1 on each. The FA 35/2 required +2 as did the FA 50/1.4. The our of the box focus was much closer than any other Pentax digital I've owned. Each generation was an improvement over the last. Paul -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
On Sat, 21 Dec 2013 12:34:53 -0500 John wrote: Just out of curiosity, does the focus adjustment/fine focus adjustment work for NON-Pentax lenses (Tokina, Sigma, et al)? Yes it does, but beware! The camera stores info for upto 20 (I think) lenses, and identifies each lens based on the LENS-ID, which is a unique number for Pentax lenses, it MAY not be unique for third party ones like Sigma. But I have only ONE Sigma that I use often (the BIGMA, 50-500), so no problem for me. You can tell a lens uses the same ID if yoy attach it, and bring up the focus-adjust screen in the menu. The find-adjust should be at '0'. When not, either you already adjusted this lens, or it has the same ID as a lens that you DID adjust ... Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
On 21/12/2013 11:08 AM, Paul Stenquist wrote: I finally got around to running some of my autofucus lenses through fine focus adjustment. The DA* 50-135 and DA* 60-250 were just about right on. Splitting hairs, I went for +1 on each. The FA 35/2 required +2 as did the FA 50/1.4. The our of the box focus was much closer than any other Pentax digital I've owned. Each generation was an improvement over the last. Paul I haven't bothered to do mine yet. I generally won't touch this stuff until I see a problem. I'm very happy with everything about this camera so far with only a couple of minor quibbles. bill -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Hi Bill, On Sat, 21 Dec 2013 12:44:09 -0600 Bill wrote: I haven't bothered to do mine yet. I generally won't touch this stuff until I see a problem. I'm very happy with everything about this camera so far with only a couple of minor quibbles. Yes, but when checking and seeing that on most lenses the focussing is something like an INCH off even on a short distance like 5 feet or so Is really annoying. And it is quite easy to fix, as said, it took me less than two hours to do more than twelve lenses. I hate it when manual focussing outperforms the camera :) Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Even a plus one or two is the difference between a sharp eyelash and a sharp pupil , but it's tough to notice without a test grid. Paul via phone On Dec 21, 2013, at 3:06 PM, Jan van Wijk pen...@dfsee.com wrote: Hi Bill, On Sat, 21 Dec 2013 12:44:09 -0600 Bill wrote: I haven't bothered to do mine yet. I generally won't touch this stuff until I see a problem. I'm very happy with everything about this camera so far with only a couple of minor quibbles. Yes, but when checking and seeing that on most lenses the focussing is something like an INCH off even on a short distance like 5 feet or so Is really annoying. And it is quite easy to fix, as said, it took me less than two hours to do more than twelve lenses. I hate it when manual focussing outperforms the camera :) Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
On 21/12/2013 2:06 PM, Jan van Wijk wrote: Hi Bill, On Sat, 21 Dec 2013 12:44:09 -0600 Bill wrote: I haven't bothered to do mine yet. I generally won't touch this stuff until I see a problem. I'm very happy with everything about this camera so far with only a couple of minor quibbles. Yes, but when checking and seeing that on most lenses the focussing is something like an INCH off even on a short distance like 5 feet or so Is really annoying. And it is quite easy to fix, as said, it took me less than two hours to do more than twelve lenses. I hate it when manual focussing outperforms the camera :) f/8 is my friend... bill -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
On Sat, 21 Dec 2013 14:37:04 -0600 Bill wrote: f/8 is my friend... :) Regards, JvW -- Jan van Wijk; http://www.dfsee.com/gallery -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
Having read this thread, I can only conclude that either I am dof or there is some some trick to being successful with this procedure. Last week I decided to fine tune my identifiable lenses on the K7. I used Bob Atkins grid, set the lenses at their widest aperture worked as close as I could get. With each lens, I took shots at -10, -5, -2, 0 +2, +5 +10. Well, with all lenses, there is absolutely no difference between the shots. OK, so I figured it was because they are slow consumer lenses and decided to try it with my Super Tak 50/1.4 - same result. I read on the web that the apply one settings can override the apply all settings and vice versa so I tried setting both with the same value. Still no luck. I also came across a program called PK_Tether which allows one to control the camera from a PC. Apparently it allows adjustments from -100 to +100! I downloaded it it connects to the camera OK but am a bit reluctant to try it. Any comments on that? Alan C -Original Message- From: Paul Stenquist Sent: Saturday, December 21, 2013 7:08 PM To: Pentax-Discuss Mail List Subject: k-3 fine focus adjustment I finally got around to running some of my autofucus lenses through fine focus adjustment. The DA* 50-135 and DA* 60-250 were just about right on. Splitting hairs, I went for +1 on each. The FA 35/2 required +2 as did the FA 50/1.4. The our of the box focus was much closer than any other Pentax digital I've owned. Each generation was an improvement over the last. Paul -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: k-3 fine focus adjustment
IMO a flat or even angled surface is a bad test. For starters the AF point on the k7/k5 is the size of the center circle. If you are calibrating a k-3 you should have an easier time. I always try to get an edge in focus and work from there. Close focusing seems to reveal the deficiencies the easiest because dof is shallower. Placing some objects in front of and behind your subject should reveal front or back focus. If you are moving between -10 and +10 and not seeing a difference you need to find some subject that will show you movement. On Sun, Dec 22, 2013 at 12:14 AM, Alan C c...@lantic.net wrote: Having read this thread, I can only conclude that either I am dof or there is some some trick to being successful with this procedure. Last week I decided to fine tune my identifiable lenses on the K7. I used Bob Atkins grid, set the lenses at their widest aperture worked as close as I could get. With each lens, I took shots at -10, -5, -2, 0 +2, +5 +10. Well, with all lenses, there is absolutely no difference between the shots. OK, so I figured it was because they are slow consumer lenses and decided to try it with my Super Tak 50/1.4 - same result. I read on the web that the apply one settings can override the apply all settings and vice versa so I tried setting both with the same value. Still no luck. I also came across a program called PK_Tether which allows one to control the camera from a PC. Apparently it allows adjustments from -100 to +100! I downloaded it it connects to the camera OK but am a bit reluctant to try it. Any comments on that? Alan C -Original Message- From: Paul Stenquist Sent: Saturday, December 21, 2013 7:08 PM To: Pentax-Discuss Mail List Subject: k-3 fine focus adjustment I finally got around to running some of my autofucus lenses through fine focus adjustment. The DA* 50-135 and DA* 60-250 were just about right on. Splitting hairs, I went for +1 on each. The FA 35/2 required +2 as did the FA 50/1.4. The our of the box focus was much closer than any other Pentax digital I've owned. Each generation was an improvement over the last. Paul -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
