Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? - Printable Version +- Opticallimits (https://forum.opticallimits.com) +-- Forum: Forums (https://forum.opticallimits.com/forumdisplay.php?fid=4) +--- Forum: Just Talk (https://forum.opticallimits.com/forumdisplay.php?fid=17) +--- Thread: Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? (/showthread.php?tid=3097) |
Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? - Saldo - 07-04-2011 A probably silly question. Are the imatest results comparable between 10mp and 16mp sections in the lens reviews, pentax section? I was particularly interested in how the following lenses performed: Pentax SMC-DA 16-45mm f/4 ED AL (Reviewed in 10mp format) Pentax SMC-DA 16-45mm f/4 ED AL (10mp) Pentax SMC DA 18-55mm f/3.5-5.6 AL WR (16mp) Pentax SMC DA 35mm f/2.4 AL (16mp) The DA 18-55mm WR (a kit lens) would seem to outperform the much raved about 16-45 SMC-DA. I am aware that the WR is a 2nd generation pentax kit lens, and pentax kits are normally deemed pretty good, but I am guessing that the imatest difference might be due to the WR having been tested at 16mp. Am I correct? Also, is anybody aware of any differences between the pentax and samsung versions of the 16-45 and the 18-55 WR? I found a pretty good price on the Samsung branded ones and, if there are no known QA issues with Samsung, I would rather go for those and save some money. Thank you very much! Aldo Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? - Klaus - 07-05-2011 Numerically the tests are not comparable - neither here nor elsewhere. If you just take the visual representation of the MTF they are ROUGHLY comparable. Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? - Saldo - 07-05-2011 [quote name='Klaus' timestamp='1309839816' post='9741'] Numerically the tests are not comparable - neither here nor elsewhere. If you just take the visual representation of the MTF they are ROUGHLY comparable. [/quote] Thanks for clarifying Klaus, much appreciated. I see what you mean by saying that the bar charts might be roughly comparable, as the max LW/PH value achievable stays the same for all 10mp tests and then for all 16mp tests. Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? - Klaus - 07-05-2011 [quote name='Saldo' timestamp='1309857652' post='9747'] Thanks for clarifying Klaus, much appreciated. I see what you mean by saying that the bar charts might be roughly comparable, as the max LW/PH value achievable stays the same for all 10mp tests and then for all 16mp tests. [/quote] Actually I meant that they are roughly comparable if you simply ignore the LW/PH numbers and just "look at the graph". Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? - Saldo - 07-06-2011 [quote name='Klaus' timestamp='1309889445' post='9756'] Actually I meant that they are roughly comparable if you simply ignore the LW/PH numbers and just "look at the graph". [/quote] Hi Klaus, thanks for clarifying. Sorry, bad wording on my part, that's actually what I had understood. Given the max possible value in the graph is the resolution limit of the testing sensor, the physical height of the bars can be used for a rough comparison betweeen lenses when tested on different sensors, while the actual values are only useful to compare performance when tested with the same system/sensor. Pentax lenses - Imatest results comparable between 16 and 10 mp reviews? - Yakim - 07-16-2011 Klaus, if that other think we talked about would ever materialize, I can add an old Pentax lens [url="http://www.fredmiranda.com/forum/topic/1009707/0#9705287"]which perform superbly on 18MP[/url]. |