ken Posted April 7, 2014 Share Posted April 7, 2014 The test was using Canon 6D with EF 85mm f1.8 lens, auto focus. Actually is semi auto focus, the anamorphic lens needs to do manual focus. BTW, this lens I have seen some seller said as 2x, 1.9x or even 1.7x. But I found the actual rate is around 1.9x might be the most close ratio. original 100% crop Quote Link to comment Share on other sites More sharing options...
ken Posted April 9, 2014 Author Share Posted April 9, 2014 Found one said 1.7x now. http://www.ebay.com/itm/121315341670 Any idea? Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 9, 2014 Share Posted April 9, 2014 If you have it just test it, shoot a round object and see how much you have to stretch it to make it round again. These lenses are almost never what they say the are, usually a little less. The Isco's say they are 1.5 but are actually ~1.41. ken 1 Quote Link to comment Share on other sites More sharing options...
tonydtv Posted April 9, 2014 Share Posted April 9, 2014 The stretch factor changes with your focus. If I remember it right, the stretch factor they put on the lens is for infinity focus. ch_d and ken 2 Quote Link to comment Share on other sites More sharing options...
ken Posted April 10, 2014 Author Share Posted April 10, 2014 I think 2x is correct. But we cannot reach to infinity to test. So usually should use 1.9x to unsqueezed. Here is sample as 1.9x. Original 1500x1000, 1000/1.9=526. so final size is 1500x526. Found center is the least anamorphic, image in sides are more like 2x. Also post a flare test, not strong is known fact. But still can use to adjust alignment. Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 10, 2014 Share Posted April 10, 2014 Yeah I have seen that effect, it is similar to extreme barrel distortion and is worse on wide angle taking lenses. I have found it needs to be corrected for panning shots or else they look funky. Quote Link to comment Share on other sites More sharing options...
ken Posted April 11, 2014 Author Share Posted April 11, 2014 Yeah I have seen that effect, it is similar to extreme barrel distortion and is worse on wide angle taking lenses. I have found it needs to be corrected for panning shots or else they look funky. What lens can take wider angle without barrel distortion? I saw 16h, or LA7200 even worse. Quote Link to comment Share on other sites More sharing options...
dhessel Posted April 11, 2014 Share Posted April 11, 2014 I believe the Isco 54 I had a while back was pretty good at its widest. If you happen to be using Adobe CC you can use the optics compensation filter to reduce or remove it. I have used it in AE but I am not sure if it is available in any other adobe app. Quote Link to comment Share on other sites More sharing options...
tonydtv Posted April 11, 2014 Share Posted April 11, 2014 The optics to compensate for barreling are pretty complex and need to be designed around a specific lens. Unless you buy a true anamorphic prime, barreling is going to happen if you're using anamorphic projection lenses, especially the 2x lenses. (The Iscoramas are a 1.5 squeeze so the field of view isn't as wide as 2x, so you get less barreling, up to a point.) dhessel is right, you can use optic compensation to reduce it, but personally, I love that barreling... Quote Link to comment Share on other sites More sharing options...
ken Posted May 11, 2014 Author Share Posted May 11, 2014 Based on my test, blue star and blank star lens have different flare performance due to coating difference, see pictures. The blue star lens has none, but blue star lens has a little bit, at least I can use it to do alignment adjustment. From serial number to tell, blue star lens is older. #5 tested picture was from blank star lens. If not care flaring, both lenses' sharpness and view angle have no difference at all. Blake.H 1 Quote Link to comment Share on other sites More sharing options...
ken Posted May 14, 2014 Author Share Posted May 14, 2014 One of my ISCO lens is decorated. :D Quote Link to comment Share on other sites More sharing options...
ken Posted November 17, 2014 Author Share Posted November 17, 2014 Sample pictures of ISCO integrated anamorphic lens with EF100 F2 lens. download address, f3.2 & f5.6: http://pan.baidu.com/s/1kTvEv0z http://pan.baidu.com/s/1ntLYGWD Quote Link to comment Share on other sites More sharing options...
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