vivah8 Posted October 5, 2015 Share Posted October 5, 2015 Few questions I can't seem to find answers to! For starters, I'm shooting on a GH4 with the Helios 58mmI'm currently waiting for my diopter set to ship, but in the mean time I was playing with the lens and I can't seem to get a sharp image out of it without any filters. Is this normal? The lens is in pretty good shape for being from the 50s.Also, given my set up, is it recommended to use the Tokina +0.4 achromat? Only other bummer is the serious vignetting when using my Voigtlander .95 25mm, but I was expecting that... Any other suggestions for wider taking lenses? Thanks! Quote Link to comment Share on other sites More sharing options...
Hans Punk Posted October 5, 2015 Share Posted October 5, 2015 It's a great little fixed focus lens and really starts producing great images when stopped down on taking lens. When used with Tokina and/or cheaper single element diopters, it is one of the nicest portrait lenses out there...really lovely image. As it is fixed focus, you will find that it won't get sharp on its own until around 4 meters and further. Stopping down on the taking lens can reduce this distance slightly, and will start to sharpen things up much more. Try f5.6 on taking lens at subject further than 4meters, and you should have better luck. Using diopters for closer distances make this lens really sing though.as for non-vignette on GH4, that you may have to experiment with. Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 5, 2015 Author Share Posted October 5, 2015 thanks! Unfortunately my step up ring is on its way with the diopters so I've only been able to really test the voigtlander and it only gets sharp stopped almost all the way down. I'm hoping thats only because its an aspherical lens. also, do I set the taking lens focus to infinity? Quote Link to comment Share on other sites More sharing options...
Hans Punk Posted October 5, 2015 Share Posted October 5, 2015 The Iscomorphot is a 'Fixed focus' or 'Focus-through' type, meaning that all focusing is done via the taking lens.The trade off is that you will need to be stopped down to get sharpness throughout the 4 meters - infinity focus range, but it can be done with experimenting on various taking lenses at various stops. A thing worth double checking is the horizontal flare - if the the streak flare has a line within it that is not parallel, that would indicate that the lens has been opened up and messed with and front and rear optics not aligned back correctly...causing the lens to not resolve sharpness.From what you say though, it sounds like it is perfectly normal - stopping down on an alternative to your Voigtlander should solve the issues you mention. Helios 44 is a safer bet to use as a taking lens on GH4. Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 5, 2015 Author Share Posted October 5, 2015 I'll do some more tests and hopefully those diopters come soon. I did have the lens cleaned from a bit of fungus on the rear element, so it being unaligned might be a possibility. Any examples on what bad alignment would look like? Quote Link to comment Share on other sites More sharing options...
Hans Punk Posted October 6, 2015 Share Posted October 6, 2015 Attached is a rough example using optical flares to illustrate.Basically if you can see any lines in the streak/ horizontal flare that are noticeably not parallel to one another - there is an alignment issue. To obtain sharpness, the optics should be perfectly aligned causing a nice parallel grouping of lines in the flare. Sometimes a very tiny misalignment can cause an anamorphic to not resolve it's true sharpness. Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 6, 2015 Author Share Posted October 6, 2015 I'm definitely thinking this is my issue. Checked the image through the camera and off and the streaks are not perfectly parallel. Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 6, 2015 Author Share Posted October 6, 2015 not to mention the front element wasnt able to be cleaned Quote Link to comment Share on other sites More sharing options...
Hans Punk Posted October 6, 2015 Share Posted October 6, 2015 If you could take a still or even better upload a short video clip of the lens making a streak flare like my rough example pic, I may be able to asses for you. Quote Link to comment Share on other sites More sharing options...
Bioskop.Inc Posted October 6, 2015 Share Posted October 6, 2015 This is strange as i've just been filming some stuff with one of these & its soooo sharp @ 4m - I just use a combo of diopters to get closer & various taking lenses to change the FOV. I don't bother trying to rack with this lens.It does sound as if you've got a misalignment problem, but the Iscomorphot isn't a great focus through lens - the Widescreen 2000 is much better at this.So try setting the taking lens to 4m (it might not be that acurate, so a bit over or bit under) & focus on something 4m away (measure it) - I know its obvious & you might need to manually move your camera/tripod forward or back. If you can't get a sharp image (it should really pop when you're in focus), you've got a problem.Try a 35mm lens or higher & set to f2.8-f4. Using a fast lens like your Voigtlander f0.95 25mm wide open, is not the way to go - if your taking lens is soft (wide open or otherwise), then the anamorphic adapter won't change that.A tip i've found for best results when trying to focus through the Widescreen 2000, is use a low powered diopter & stop down a little - the focus range won't be huge (about 2m if you're lucky) & so racks are very subtle, not dramatic. Hans Punk 1 Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 6, 2015 Author Share Posted October 6, 2015 So here is a video I managed to capture late last night, not the best, but hope it will do. The lens will only begin to get sharp stopped all the way down so I think it is definitely misaligned, not to mention the horrible glare from the front element. Quote Link to comment Share on other sites More sharing options...
Bioskop.Inc Posted October 6, 2015 Share Posted October 6, 2015 Yes, that isn't how it should be at all - you should have 2 lovely flares (green & red).Looking at mine just a minute ago, you could probably realign it yourself - might take a few goes to get it right, but do-able. Hans Punk 1 Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 6, 2015 Author Share Posted October 6, 2015 any info on how would be great, man this lens is causing me a ton of trouble, but I still cant wait to use it hahaha Quote Link to comment Share on other sites More sharing options...
Hans Punk Posted October 6, 2015 Share Posted October 6, 2015 Yep that is misaligned to hell.Good way of getting it corrected is to flare the lens in a dark room while attached to camera, and rotate front element until all lines are parallel in the streak group.I've since sold my Isco S8 and can't remember offhand the best way to disassemble, I think it is by detaching/unscrewing the front, then rotating it again to align. Bioskop is very knowledgeable, he might know by looking at the body of his lens as to the likely way of opening that front. I seem to remember the rear element is seated firmly in the body design, so accessing and adjusting the front element rotation is the way to go. Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 6, 2015 Author Share Posted October 6, 2015 You were right, the front comes off quite easy. I was able to align it to the best of my ability with the voigtlander, should be easier to fine tune when I get that step up ring for the Helios.Now we're talking! Thank you so much! Hans Punk 1 Quote Link to comment Share on other sites More sharing options...
Hans Punk Posted October 6, 2015 Share Posted October 6, 2015 Cool.To really get it as sharp as you can, and once you have your step ring/ helios set up - lock your camera down on tripod or flat level surface and point at a light source to flare the lens. Pan left and right on a level horizontal axis to check all horizontal streaks are parallel to each other. Also you can aim at an object at infinity (or at least a decent distance away). Use zoom magnification to punch in as much as you can, rotate front element until object is as sharp as you can get. Stopping down on taking lens can help judge the finite adjustment to get things nice and crisp. Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 17, 2015 Author Share Posted October 17, 2015 Thanks, this was all extremely helpful. This lens is incredible when used correctly, especially with the Helios.only thing left to desire is a wider taking lens. Anyone know of anything 25mm or wider that doesn't vignette horribly? I want to look at the canon FD 20mm, but was curious if anyone had solved the problem before I go on a spending spree haha Quote Link to comment Share on other sites More sharing options...
Flynn Posted October 17, 2015 Share Posted October 17, 2015 Does autofocus with the taking lens work on focus through lenses? Quote Link to comment Share on other sites More sharing options...
vivah8 Posted October 18, 2015 Author Share Posted October 18, 2015 In my limited experience thus far, I'd say no.Besides, I wouldn't suggest using autofocus for video anyhow. Quote Link to comment Share on other sites More sharing options...
Flynn Posted October 18, 2015 Share Posted October 18, 2015 Thanks. I recall reading reading that autofocus worked on the LA7200 and can't see why it wouldn't work on these focus through lenses. Quote Link to comment Share on other sites More sharing options...
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