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Bold

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Everything posted by Bold

  1. I though Rich was re-housing Iscos - or is that a separate endeavor?
  2. This ^ I imagine it's largely a matter of financials: can someone (with the means and machines) create an Isco clone at a price that is both competItive and turns a profit. My guess would be no, otherwise someone would have jumped on this by now. Doesn't mean it couldn't happen in the future though...
  3. Through a combination of small arms fire and hand-to-hand combat techniques, I was able to get this: The apartment in the background is at least 300ft away. It may not be perfectly crisp infinity, but it's within an acceptable margin of error for my uses. Eight inches out to (good enough) infinity, single focus, no vignette (probably down to 50-55mm), light weight, 2x anamorphic. HUZZAH!
  4. No luck. I think there still may be 1-2mm of space between the elements due to the construction of the parts, which I don't know if I can resolve. I don't know if that extra millimeter or two is enough to make a difference. On the plus side I measured and I can focus down to 8 inches. Unfortunately it does not offset the infinity issue for me - what's the point of widescreen if you can shoot some nice, crisp landscapes, right? I'm pretty despondent at this point...
  5. A friend of mine had a bit of a genius idea. Take a piece of lens tissue and put it between the glass elements, assemble everything and tighten/adjust the helicoid so the front glass element just barely touches the anamorphic with the tissue in between. Mark the position of all pieces on the outside of the mod. Disassemble the mod, remove the tissue, then reassemble and tighten/adjust everything to the markings, effectively getting to the two pieces of glass as close as possible without them touching. It may not be enough to resolve true infinity, but the unit may be able to focus far enough to mitigate the issue. I'll try this when I get home. I'm still wondering about John Barlow's negative achromat solution, and what kind of focal length I would need? Achromat math still confuses the hell out of me no matter how many times I read about it. I found a 55mm diameter lens with a focal length of -4000mm. Is that even in the ballpark?
  6. Thanks Gabriel! Rich posted some pictures earlier in this thread which shows his mod focused at infinity, so it be should achievable on mine (in theory). The 3D printed collar only works with the polyurethane piece (this is the part that physically screws onto the front of the B&H) that I made for myself. Without that, the 3D printed part is of no use to anyone. I may consider recreating the whole assembly and selling it, but not until I can resolve some quality control issues - and hopefully the infinity issue. A note about helicoids: the ones on eBay from China that I've gotten use a terrible lubricant which loses viscosity at lower temperatures. Basically the rotation is very stiff when it gets cold. If you experience this problem, you can disassemble the helicoid (don't lose the screws!), remove the grease lubricant and replace it with some white lithium grease for much better focusing action (although reassembling a helicoid in the correct order takes some patience!). This is actually the first thing I do now when I get a helicoid from eBay.
  7. My initial test was disappointing. The mod seems to suffer the same issue QuickHitRecord mentions near the bottom of the first post in this thread, where it can't quite seem to get to infinity. The taking lens is a Helios 44 (not 44-2) that focuses to infinity just fine on its own and is flat up against the back of the B&H. The front element of the mod is sitting in the helicoid nearly touching the front glass of the anamorphic. John Barlow mentions a negative achromat further down in the same thread as a solution. Anyone know of this and how to acquire one? Richg101 (or any other B&H modders out there) do you have any other thoughts/suggestions? I'm hesitant to shorten the distance between the front glass and anamorphic any further because I'm worried about the glass touching each other. On a positive note, the long helicoid allows me to focus down to about a foot (maybe less!) on my Helios without noticeable vignetting. Some mighty focus breathing, though. I'm very close to finishing this mod and would hate to think all my effort has been for naught. Any help on this issue would be greatly appreciated! |. . | .|
  8. Finally, a progress update. A combination of polyurethane casting and 3D printing to mate the B&H anamorphic with the helicoid. A couple 3D printed brackets to hold the front glass element in the M58 Helicoid. Plus some invaluable help from a friend (with a workshop) for marrying the finderscope bracket with the 15mm rail system. The helicoid pictured is 25mm-55mm, in hopes the longer travel distance will allow closer focus. I have a 17-31mm helicoid as a backup in case vignetting on the longer helicoid is too much. This has been an agonizing process full of mis-steps. Fortunately, no anamorphics were harmed in the making of this prototype. Although two helicoids did not make it (RIP). But I'm only a few days away from testing. Everything fits snugly so I'm crossing my fingers that the test footage will be worth the absurd amount of time I've put into this. I hope to have good news soon.
  9. More info on Kowa and Rectilux vs SLR Rangefinder here. I seem to remember Focus Module not performing on the same level as the other two. I'm sure there are more posts on the subject...forum search is your friend! Cheers, |. . | .|
  10. Nice work, Bioskop. Love that opening timelapse!
  11. Yes one should do their research before buying one of these to avoid unrealistic expectations.
  12. That's the DS-1609 model, the WS-13 listed above is far rarer and better in many respects. $320 USD for a DS-1609 is actually a good deal!
  13. Cool. If it turns out the Kiron doesn't meet your needs, the purchase won't have emptied your wallet - and it's easy to resell since it is a well-respected lens among photographers. I'm keen to see how it performs for (anamorphic) filmmaking. I picked up one of these myself, but haven't been able to use it, as I'm still trying to assemble my anamorphic setup. Please post back with footage/impressions if you get a chance! Cheers, |. . | .|
  14. Timpy, If you want a parfocal super zoom, you're unlikely to find one that isn't push-pull. That is, you won't find one with separate zoom & focus rings. Your best bet may be the first (and some argue the best) super zoom, the Kiron (Kino Precision) 28-210mm. It is also found under the name Promaster Spectum 7. KINO PRECISION was started up by engineers who moved from NIKON to make lenses that equalled, or in many cases, were superior to OEM lenses. Their fit, finish, mechanics and optics were top quality. The 28-210mm is a parfocal lens where the front element doesn't turn when focusing. When focused at 200+mm, focus stays spot on down to 28mm. When focused at 28mm, it is a tiny bit off when zoomed to 200+mm. This is attributed to a small amount of human focus error at the low end (28mm) and not a fault in the lens. It's most commonly found for Canon, but I've seen it in Nikon, Minolta, Konica and Pentax mounts. It is very affordable. Here's a little Kiron info from a guy looking for a zoom for his Century Optics and Panasonic anamorphics: Hope this helps! |. . | .|
  15. That eBay seller is a rip-off artist. Anything he's selling, you can find cheaper elsewhere.
  16. Cool, Like you said, the lens is heavier than the camera. That focus crank is an obstacle when it comes to supporting the lens (it pretty much excludes using a lens collar), I'd be interested in seeing your solution. Thanks for reminding me about the stick! I had totally forgotten it's been rolling around in the case my lens came in. Cheers, |. . | .|
  17. Nice work freeman! I have this lens (and GH4) also, but haven't shot much with it yet, I'd love too see a pic of your shoulder rig if you've got one. What are your thoughts/experience using the side-mounted zoom handle (versus manually turning the barrel)?
  18. My local camera shop recommends using lens tissues with 95% isopropyl & breath, or using lens tissues with naphtha. I use the naphtha method with excellent results.
  19. I am sure I am in the minority, but I see Abrams' Trek reboot as reason to expect the opposite. https://www.youtube.com/watch?v=6B22Uy7SBe4
  20. Lens-cylopedia updated with details for Rathenower Rectimascop 48/2x - info courtesy of Julian Krause!
  21. This is probably the way to go, just use caution with the type & amount of lubricant — otherwise there's the risk of the lubricant getting onto the inner glass element when you push-pull. And Tito to your point, I think the subject warrants its own thread
  22. It's obvious this guy's been reading this thread, his latest offering now incorporates a helicoid. I've considered selling one of my B&H's when I'm done and put on eBay for $100 less just to undercut him. Although that would still make me a profiteering a$$hole. However I would like to recoup some of my cost in materials and R&D. What do you think is a fair asking price for a modded B&H?
  23. If you crank the dial to 11 and leave it there, it loses its meaning/impact. Nothing wrong with using color saturation judiciously, but its ever-presence in season 2 pulls me out of the story. Not so much that I won't stop watching, but enough that I'll complain about it
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