Samuli Vahonen Offline Upload & Sell: Off
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Small update from last week and weekend testing & shooting.
- Contax G21 and G28 seem to work well with SLB-50-1500PM reversed on stock filter stack cameras (tested A7r and A7v2) as simulated and confirmed in this thread . Final verdict for G21 is not yet out as I did not do any normal shooting (=not infinity, boke involved) with the lens, just infinity shooting, where it seemed to perform fine.
- Contax G21 doesn't work with SLB-50-4000PM on Kolari v2 . Discussed this with Hirohiko and the simulations made in post p3 #14 were calculated with 0.8mm filter stack thickness, while the optical thickness of filter stack is ~1.5mm. Hirohiko re-calculated (thanks!!!!) and assuming 1.5mm optical thickess SLB-50-2000PM is optimal, but also SLB-50-2500PM works. ==> made 2nd order to OptoSigma for SLB-50-2000PM and SLB-50-2500PM.
- ZM 2/35 Hirohiko simulated (thanks!!!) that SLB-50-3000PM should be optimal for standard cameras. Hirohiko also gave me help to simulate this one on Oslo software, and to me also the SLB-50-3000PM seems optical (but I still struggle with the software and understanding all the parameters). However it did not work in practice - correction is way too weak with SLB-50-3000PM. Not sure why but there must be something wrong on parameters we use to simulate as other simulations seems to be spot on. As correction was not enough I tried moving the lens to one of my Kolari v2 modified A7 bodies and it seems that this combo works well . I did shoot quite a lot my normal boke shooting and landscapes, and it seems that SLB-50-3000PM on Kolari v2 works - however I want to test it with SLB-50-2500PM and SLB-50-4000PM before giving "the final verdict". For me this lens is special due to it's boke and transition from focus to boke, and I'm really looking forward to shoot with this lens on coming spring & summer. Some native field curvature remains in corners, so for people looking "perfect lens" ZM 1.4/35 or Voigtländer are better options - In my opinion unless you like the rendering style of ZM2/35 I would not consider this lens worth the effort.
- ZM 4/18 I did test only very shortly with 58mm Hoya +1. For landscape shooting results with standard filter stack camera seem to be OK (hard to say does it correct field curvature when DOF is gigantic due to short focal length). On the few landscape image I shoot corners were sharp when shoot with f/8 and f/11, and I could not detect CA or astigmatism in corners. Naturally 58mm Hoya filter frame is too thick and small vignetting can be seen in corners. I checked and no matter how I skrew the filter in place it always stop in same place --> if this is good solution for this lens optically I'll just cut the filter frame so that it can still hold lens cap but corners don't vignette. I'll try this lens at some point with SLB-50-3000PM which is optimal according to simulation for standard thick filter stack camera - however I can't imagine any way to attach the filter to lens without generating vignetting, testing can be done by 2-sided-tape but any permanent solution will vignette. Also OptoSigma doesn't sell in larger 60mm size suitable focal length, so this one will be challenging.
- Both G21 and ZM18 cause very severe vignetting and colour errors on image edges/corners due to extreme ray angle on A7, A7r and A7v2 . I was not planning to get A7r v2 but it seems it's mandatory if I want to use these lenses. G28 is almost as bad, but most likely I can correct it with software. ZM2.8/25 and ZM2/35 better, but will require color correction on A7, A7r and A7v2 regardless is camera Kolari converted or not (assuming you don't want pink/magenta sky in corners etc.). I have not done controlled tests, but A7v2 seems to cause little less color cast than A7 and A7r - also that needs to be tested. Too much testing, too little photography...
It's good to end day by dreaming of going shooting with G21, G28, G45 and G90 on next summer This lens "family" has my favorite rendering style, and it seems it's finally feasible to shoot them with digital camera.
Samuli
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