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Bold

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Posts posted by Bold

  1. I didn't know that the theme of a video would help to find a FF…

    It doesn't necessarily, but i if you're doing something staged like narrative, size & form factor might not be as big a deal as if you were shooting something where the camera rig had to be more light & nimble, like a documentary or event coverage.

    I use an el cheapo Fotga DP3000 follow focus.  There are better products out there, but it is small, reasonably sturdy and fit my budget,

    Cheers,

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  2. The best Bauch & Lomb test in my opinion

    Yes, Logan Stewart (Vimeo user Variables of Light) really seems to get the most out of his Bausch & Lomb. And his is a modified B&L using the cooking anamorphic tutorial.  I'm wondering if the quality of his footage is a result of how he did the lens mod, how he handled the modded lens (to get better results than this), or both.

    I found this tidbit on a home theater forum:

    "I discovered that the astigmatism adjustment on this lens could be set to closer than the minimum of 50 feet by turning it past this setting and pushing the front element housing down to it's maximum depth within the lens body. This in effect provides a projection distance that I estimate to be at about 20 feet or so."

    So this technique apparently takes the projection distances from 50 feet to about 20 feet. I wonder if adjusting the B&L in this manner would reduce the minimum filming distance to closer than 12 feet.  I also found this in an ebay listing:

    "turning the ring at the front - It makes no difference to the focus of the lens of the camera. Conversely, all the focusing is done by the lens on the camera. This "focus" ring changes the distance between the two cylindrical lenses inside. This does not affect the focus, instead it affects the anamorphic ratio. For most video and still image purposes this is not critical, however it would be critical in a movie theatre."

    Which would explain why Ken and enny were unable to adjust focus on the B&L itself.

  3. enny, I appreciate the info and the picture of your setup!

    I watched a clip of Roberto Lopez' chopped B&L which used a 24mm Nikon. In a later clip there's a shot at 0:45 where the curvature in the pillars is very pronounced. I don't know if that's a characteristic of the B&L, a result of being too close to the pillars, a byproduct of the lens hack, or some combination.  But it's definitely something I want to avoid (or at least minimize).

    Are there any other tips, details, or footage you could share?  Can you explain how you do single-focus with your setup?  Do you focus with the B&L, or the taking lens?

    Thanks again!
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  4. The B&L lens I owned before is not focusable.  The focus ring is fake.

    I wonder if there was variation in the manufacture, where some lenses did not allow focus, while others did.  I've read at least one instance where a B&L owner could do nothing with the focus ring, and it turned out that because of the age of these things, the rings can become solidly stuck in place due to sediment, grime, etc. And as a result, it required an automotive tool and an inordinate amount of torque to un-stick!

    I would say for the same price lens to me with similar size/weigh, ISCO HD attachment has 10 times better.  There  was a sample picture I posted before: http://www.eoshd.com/comments/topic/8047-need-help-on-anamorphic-lens/

    Thanks - though as I said in my first post, I already bought a B&L - so I'm really looking for hard data on those, rather than what better options are available.  Mostly I bought it as something I can tinker with...maybe I can learn from, and if I break it, it hasn't broken my wallet!  If I can collect info from B&L owners and add some of my own in the process, maybe it will be of practical use to other folks here - particularly novices like myself!

    Cheers,

    |. . | .|

  5. I have read that the B&L Cinemascopes are large, heavy, cumbersome, low on flare, and require gymnastics to override the minimum focus distance. So I don't have grand expectations for it, but for 75 bucks I can afford to experiment.

    I'm sorry the Rectimascop didn't work out, that's a bummer.  But I'm really looking for usable details, data, and experiences from Bausch & Lomb owners.

  6. While I'm waiting for my new helicoid to arrive for my Bell & Howell Projection Lens, I picked up a Bausch & Lomb Cinemascope Projection Attachment I.  I don't have much interest in dual-focus, but the lens was cheap & in good condition, so I thought I'd give it a whirl.  I haven't found a whole lot of info on the lens yet, though this mod looks interesting.

    Like my B&H thread, I'm hoping B&L owners will weigh in with any details, data, or experience using this lens.  I won't sink my teeth into this project until I've finished with my B&H, but I figure I'd get the ball rolling.  And maybe down the road, helpful info can be added to the Anamorphic Lens-yclopedia.

    I'll bust out the caliper when my lens arrives to get some measurements, but the rear thread is reported to be 70.6mm. And I found a few details about disassembling the lens hereherehere, and here.  From what I've read, the lens is not big on flare due to the coating though I've seen a few clips on Vimeo that show some decent flares.

    So anybody have B&L information to contribute to build up the knowledge base around this lens?

  7. My Antares finderscope clamp arrived today and it fits great:

    Antares01.thumb.jpg.d59dd6b2cf1e240b58d7

    Antares02.thumb.jpg.3a42f45b67f453c1fb4b

    Antares03.thumb.jpg.31b27e08edc2b8378dd4

    Antares04.thumb.jpg.a9986354c3b460f9d758

    Antares05.thumb.jpg.a06221f1e4173bf6b8c4

    Here I reversed the bracket, which puts the base at the end that joins the taking lens.  However, this makes the unit nose-heavy:

    Antares06.thumb.jpg.cba4f6b5487ccefa7119

    Antares07.thumb.jpg.b970552f50e0e53412e1

    I think it's best to have it clamped the other way around as in the previous pictures - adding stability to the end that gets the most vibration/movement (from focusing).  The top screws can be used to help visually align the anamorphic, too.  As mentioned, I'll have have to do do some modding to flatten the rail base, but I am very encouraged by the results!  All in all, $37 well-spent, I think!

    Cheers,

    |. . | .|

  8. Thank you for the kind words!  

    Another possible solution is to take a cast of the original front housing, and a cast of a female thread (on my case (58mm), then combine them into one mold.  Then cast those in something like brass or rigid polyurethane.  Then cut & combine them so one end is a perfect fit for the anamorphic and the other end is a perfect fit for the helicoid.  Brass would be ideal but polyurethane is more within my budget.  For under $100 I should be able to attempt several casts.

    Thanks for posting the pics of your B&H's.  I'm optimistic the dual clamp rings of the Antares finderscope bracket provide the stability you need.  I should be able to verify in a few days.  I'll also let you know what I find out from the 3D printer.

    Cheers,

    |. . | .|

  9. i recon a m58 helicoid will work. 

    Wish I had the caliper before I bought the m58 :stuck_out_tongue_winking_eye:

    looking closer, mine is actually a m52 helicoid

    Oh well.  That's what I get for being too eager and not being patient & methodical enough.  I may get an m52 helicoid, although I don't know if the thread mount would fit around the 53.88mm end of the anamorphic.  Rich, can you verify?  I may go ahead and try to work with the m58, still debating

    I'll really want to find a permanent solution for attaching the helicoid to the anamorphic.  Although the anamorphic's 53.88mm thread seems proprietary so I don't know if there's anything I can kitbash in terms of adapter rings or pipe threads.  I don't know if 53.88mm equates to some kind of 54mm thread, or a 2 1/8in thread, or something else.  I'm going to swing by the 3D printing place tomorrow and chat with them to see if they have any thoughts on a solution, and to see what it would cost to print a semi-rubber lens holder to fit the m58.

    Bold, if I don't figure everything out from the posts here I'll message you about a few bits and pieces, ok?

    Absolutely!

    Again a great big thanks to Rich, QuickHitRecord, Tito, nahua, et al, for all the great info.  I wouldn't have made it this far, I hope the info I'm adding is proving useful for folks.   My goal is to have a finished version in September and post back with an organized, step-by-step review of the process. 

     

  10. Thanks Gabriel, I have a Redstan for my Century Optics and it's a fantastic piece of gear.  For the B&H, I want something that will both support it's weight and provide the flexibility to slide forward and back a little, as a couple of my lenses change body length when focusing.  I thought of fabricating something using parts from a hardware store but in a moment of inspiration I realized the product already existed.  Volia:

    4386_1_.jpg

    The Antares 50mm finderscope clamp:

    • Weight: ~170g
    • Two ring clamps for added support & stability
    • Ring Diameter (inner): 62mm. The diameter of B&H varies along the barrel, ~50 to ~55mm along the area the clamps would go, so it should fit without problems
    • The screws are plastic/nylon, so they won't scratch the barrel
    • Slotted rail base, so the the lens can slide forward & back while the clamp holds the anamorphic in alignment, the base also has a screw for locking it in place
    • The base is curved to fit on a telescope, but that can be belt-sanded flat, and attached to a 15mm rod bracket.  I have one of these, I'm thinking I will also belt-sand the top of that flat, then screw the two pieces together, so that the rings sit on a bracket that has adjustable height
    • Price: $37 with shipping

    Finderscope brackets are also available 80mm, 90mm, and possibly other diameters - opening up possibilities to folks here with other sized anamorphics.

    My bracket should arrive next week.  I'll have to hit up a friend of mine for the machining/sanding, but that should be quick work.  I'm moving in a week, so I probably won't get to this work until September.  But I will most definitely be posting back here with photos & conclusions.

    As for my o-ring issue, I'm contemplating getting something 3D printed to fit the front element into the helicoid.  There's a place in town that can do rubber-like material.  It's just a matter of what the cost is.

     

    Cheers,

    |. . | .|

  11. what is the focal length (or equivalence) for prime lens without vignetting? 

    I haven't found any clear info on that yet.  For full frame it's ~85mm.  Not sure what that translates to for Micro 4/3.  One B&H owner told me he's using a Nikkor 50mm f1.8 with negligible vignetting on his GH4, but the key word is 'negligible.'  I guestimated a 55-58mm prime with angle of view of ~40 degrees would do, but my test indicates otherwise.  Any insights or firsthand experience from forum members would be greatly appreciated!

  12. One of the o-rings arrived today.  I spent a couple hours cutting & sanding it down to fit in the helicoid.  The real trick was getting the the glass to align (relatively) parallel with the anamorphic lens.  I'll probably seek a more accurate solution but it was enough to do some tests.  Here is the helicod and the anamorphic, the anamorphic has some white pipe thread tape around it to help secure the helicoid reverse threads.

    prototype0.thumb.jpg.7d7ff867f637d3c5dd0

    Helicoid attached, focus fully extended.

    prototype1.thumb.jpg.a177b98696e09995350

    Helicoid fully retracted.

    prototype2.thumb.jpg.3efa7d3d56085eedf16

    Helicoid with improvised (but extremely snug) rubber o-ring.

    prototype3.thumb.jpg.c4d69bc6cfa9eab1964

    And a 58mm lens cap for good measure.

    prototype4.thumb.jpg.057e5754ecf8d45376e

    So I threw on my Helios 44 (not Helios 44-2) 58mm and did some quick & dirty video.  Here are a couple screenshots:

    BH-test.thumb.jpg.85f43fb0ef0e820e281270

    Initial thoughts:

    • Aspect ratio of 3.55:1 shows minor vignetting.  Crazy flare.
    • I don't think I was quite able to hit infinity, but I think I can resolve that by adjusting distance between the elements by reseating the glass in the o-ring.
    • I need to secure the helicoid to the anamorphic assembly, there was a small amount of play there when shifting focus.
    • There was a lot of alignment shift going on.  The B&H will need to be locked down to a rig tightly to ensure the anamorphic remains aligned vertically.
    • I still have a lot of work ahead to take this from work-in-progress to finished product, but so far the results are encouraging.

    Other miscellany:

    • A rig may not be small enough to be considered run-and-gun, but would still respectably light & portable.
    • Plenty of Series 7 adapters available to marry most lenses to the B&H, I even picked up a 72mm to Series 7 for my Angenieux 12-120mm

    mod-adapters.thumb.jpg.64ca31d8cec7e6eae

    • Still need to test the 12-120mm on the B&H.  Not the ideal, as it will vignette, but it will do for the purposes of testing parfocal zooming.
    • Once I come up with a more permanent configuration for everything, I'm going to affix a focus gear around the helicoid for follow focus.
    • I'm going to wait until the permanent configuration is done before I start slapping wide angle attachments on it.
    • Other reasons I chose the Raynox 0.66x over the Sony 0.7x wide angle is that it is not only smaller in size, but it also has a 72mm front filter thread.

    That's all I got for now.  More soon...

    Cheers,
    |. . | .|

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