next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - Printable Version +- Opticallimits (https://forum.opticallimits.com) +-- Forum: Forums (https://forum.opticallimits.com/forumdisplay.php?fid=4) +--- Forum: Sony (https://forum.opticallimits.com/forumdisplay.php?fid=14) +--- Thread: next PZ lens test report: Sigma AF 19mm f/2.8 EX DN (/showthread.php?tid=2041)

next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - Klaus - 02-05-2013 Could be better: http://www.opticallimits.com/sony_nex/786-sigma19f28nex next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - thxbb12 - 02-05-2013 [quote name='Klaus' timestamp='1360098552' post='21805'] Could be better: http://www.opticallimits.com/sony_nex/786-sigma19f28nex [/quote] Thanks for the review, Klaus. Pretty disappointing border performance. I wonder how much is due to the NEX-7 sensor issue. Would be interesting to see how well it performs on a NEX-6 as well as MFT. next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - joachim - 02-06-2013 Hi Klaus Thanks for sharing this. Could you remind me how you assess distortion? Does the NEX apply corrections like an OLY PEN? Joachim next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - Rover - 02-06-2013 It seems as though the NEX-7 makes borders look ugly on any lens. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/blink.gif' class='bbc_emoticon' alt=':blink:' /> next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - Klaus - 02-06-2013 [quote name='thxbb12' timestamp='1360105365' post='21810'] Thanks for the review, Klaus. Pretty disappointing border performance. I wonder how much is due to the NEX-7 sensor issue. Would be interesting to see how well it performs on a NEX-6 as well as MFT. [/quote] Yeah, yeah, Ok, I will get a NEX 6 then. next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - Klaus - 02-06-2013 [quote name='joachim' timestamp='1360129231' post='21812'] Hi Klaus Thanks for sharing this. Could you remind me how you assess distortion? Does the NEX apply corrections like an OLY PEN? Joachim [/quote] There is no trickery involved here. The RAW converters don't do it under the hood so you can switch it on or off. next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - joachim - 02-06-2013 [quote name='Klaus' timestamp='1360141021' post='21815'] There is no trickery involved here. The RAW converters don't do it under the hood so you can switch it on or off. [/quote] Thanks, so did I understand you right, that distortion correction is not part of the NEX system as it is for µFT? That's quite interesting - I thought that due to no optical finder that you can do this is a strength of the mirror less approach. Though, as now well understood, leading to weaker corners (MTF wise) on lenses which heavily rely on distortion correction. next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - Mistral75 - 02-06-2013 [quote name='Rover' timestamp='1360139222' post='21813'] It seems as though the NEX-7 makes borders look ugly on any lens. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/blink.gif' class='bbc_emoticon' alt=':blink:' />/>/> [/quote] Not any lens: any non-telecentric wide angle lens or ultra-large aperture lens, because of the rays with a high angle of incidence they produce and the so-called "crosstalk" caused by the micro-lenses and filter layers in front of the sensor. next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - Klaus - 02-06-2013 [quote name='Mistral75' timestamp='1360146834' post='21821'] Not any lens: any non-telecentric wide angle lens or ultra-large aperture lens, because of the rays with a high angle of incidence they produce and the so-called "crosstalk" caused by the micro-lenses and filter layers in front of the sensor. [/quote] According to Sigma these ARE telecentric lenses. next PZ lens test report: Sigma AF 19mm f/2.8 EX DN - marco - 02-06-2013 [quote name='joachim' timestamp='1360143751' post='21819'] Thanks, so did I understand you right, that distortion correction is not part of the NEX system as it is for µFT? That's quite interesting - I thought that due to no optical finder that you can do this is a strength of the mirror less approach. Though, as now well understood, leading to weaker corners (MTF wise) on lenses which heavily rely on distortion correction. [/quote] Do you ask, if the NEX has a distortion, CA and vignette in-camera correction? All models after the 5N have it, but it is build in the camera, so you have to update the firmware. In this way it's very flexible, because it can match lens and camera very well, but if there is no firmware update for newer lenses, you are ...