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Erkan Umut

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Posts posted by Erkan Umut

  1. Lasse, you are the topic starter, would be please inform us on any news, if possible and any. Sincere thanks!

     

    If you want to support this thread and help in optical related things, let's continue on the mount for the reasonable priced lenses with good performance since it won't be any bloody expensive camera (at least I hope)...

     

    Thanks!

    • Upvote 1
  2. Benjamin,

     

    I forgot to add this:

     

    If you use tubes for macro you should know the exposure loss to be compensated ("effective f/stop", because it is a ratio of focal length and aperture size).

     

    This is not a problem with the close-ups as the effective aperture no longer increases.

     

    Hope this and others help...

  3. "Macro lenses are usually C-mount lenses. While "Normal" C-Mount and CS-Mount lenses are used at distances of 50cm, 1m or even hundreds or thousands of meters, Macro lenses are typically used at very short distances, this even could be a few millimeters. They may or may not be used on larger distances. There's no fixed limit for the distances that distinguishes Macro lenses from "Normal" lenses. Macro lenses however work better on short distances than on far distances. Simply because they were designed for this purpose."

  4. Benjamin,

     

    If anything should be worked as a macro, the elements should be far away from the film/focal plane in order to get enlargement just the regular way. Example, extension tubes for not macro lenses.

    I remember, when I was working with an Arriflex 35IIC years ago, the director wanted an extremely large detail of a subject. I had no macro lenses in my lens set. I found an easy but unofficial solution cause the lens mount was ARRI Std mount. What I did? I shifted the tele lens forward from the plane.

     

    The sophisticated lens designs apply the element structure (esp. in S8 cameras) having added macro feature for doing the same in a lens seen as a macro lock mechanism on the rear barrel (designated as M). This is possible by altering the back focus distance.

     

    (The simplest form is Close-up filters +1,2,3 etc. for the frontal element to be able to create a virtual bigger image.)

  5. We are talking about whether a 7mm lens for a large format camera will give the same angle of view as a 7mm lens designed for a smaller format camera - ie. when used on a Super8 camera. The answer is YES.

     

    As for lens circle and what it sees, that is not the same thing as angle of view. The size of the lens circle can vary all over the shop from one manufacturer to another. The angle of view is that which is visible within the frame. That's the definition of view angle - what the frame sees, not what the lens circle sees.

    Absolutely, YEEES!

     

    Further on optics, the other topic followers gonna f*ck me I think :D :

     

    The diameters of the circles of confusion in lenses for Super 8 format will be smaller than any of other for larger formats, so the Depth of Field will be shallow in smaller formats relative to larger formats. (Think the light flow as a cone towards the image plane just after the rays are refracted in the lens.)

  6. Carl, try to shoot three pictures having a head from, say, 3 meters with w/a, normal and tele lens each w/o altering the distance. Then match those two pictures shot w/a and normal to the head taken with tele by enlarging. Look at the background, will you see any difference?

  7. By the way, I am tired of this Editing limitation (so short)!!!

     

    Maybe, it would be better to move our discussion to the another newly added topic, some people following the post might be angry. They are right, we done it so detailed in optics. Also, by doing this, some other people may even join who doesn't follow this topic...

  8. Benjamin is right for me, Carl, thou I couldn't open the images he is attached.

     

    The perspective never changes if you don't alter the subject to camera distance (for example zooming, you crop from the image size, like enlarging a part of a picture, in contrast to dollying/traveling). I know this good, because its my business, as well as I teach it at the university in cinematography classes. Wide angle lenses tend to create fake perspective visuals. But what changes with wide angle lenses is the closer subjects to camera gets bigger faster relative to the rest. Normal and esp. Telephoto lenses show this very less compared to the W/A.

  9. The equations are not from any book on photography by the way. They are derived from Ancient Greek formulas, the same formulas that camera designers would used when specifying lenses in the first place. We can see why a lens is marked in terms of focal length instead of field of view. The frame width variable belongs to the camera. The focal length variable belongs to the lens. The angle of view is a function of both camera and lens.

     

    What a simple and yet well enough description... Many thanks!

  10. Wow, Carl and S8 Booster thanks a lot!

    When it comes to the math formulas and pictures, I am dying for them :rolleyes: .

     

    Some years ago I had began to read the Arthur Cox, Sidney F. Ray and D. F. Horne's books, as well as some excellent Russian books but quit. The books are excellent while complicated...

  11. However, it doesn't really matter what focal length you call "normal" - the important point is that all lenses of the same focal length will give you the same angle of view on a given camera. So for example, any 7mm lens, whether it was made for Vistavision cameras, or for 35mm cameras, or for 16mm cameras, they will all give the same angle of view on Super8.

     

    Carl,

     

    Are you sure?

    I am not.

     

    Some years ago, I've rented a Super16 camera package from a house. They have all my selections for the lenses, but one. They offered me a 35mm format lens instead of. The one not available and the offered were the same F/. Then I suspected of that lens giving me the angle of view I want.

     

    So I have posted on Cinematography.com and the best answer came from Mr. David Muellen, ASC, who is very knowledgeable DoP and seen on the posts mostly.

     

    Any lens made for a format, when used in a smaller format than its created for gives narrower angle of field!

     

    Any thoughts?

  12. I'm not sure I understand why C-mount lenses should be regarded as limiting one to "telephoto" shots in Super8.

     

    If, for example, the "standard" lens for Super8 is 15mm, then for "standard" shots on Super8 one obtains and uses a 15mm lens. It doesn't matter whether that 15mm lens was designed for larger format cameras. All it means is that on a larger format camera the 15mm gives a wider angle of view.

     

    If one wants the same wider angle view on Super8 then one just gets a lens with a shorter focal length.

     

    C

    Exactly Carl,

     

    What we learned in the advanced photographic courses at the university is that: There is a simple math formula, if you want to decide a normal lens for an image format covered, you should take the format's diagonal into account, e.g. normal lens = √a2+b2, where a - width, b - height or vice versa. The results can be fractional, so the numbers are rounded.

     

    The focal length never changes in a lens for any format, but the angle of view.

  13. C-mounts made for TV or CCTV had no such restrictions however, and can sometimes protrude far enough to cause damage. I recently repaired an ACL that had mirror damage due to the incautious fitting of a TV lens. Super 8 Beaulieu cameras like the 4008 with an oscillating mirror have an aperture plate behind the C-mount that tends to prevent these lenses being screwed in so far as to hit the mirror, which is probably a good idea to consider with this new camera.

     

    A C-mount is the logical choice for a reflex mirror S8 camera, plenty of lens options and adapters for other mounts, although maybe a micro 4/3 mount would work also. Anything with a shorter flange depth like CS or D-mount leaves very little room for the mirror. The French firm Ercsam pioneered the reflex guillotine mirror with their reflex Camex standard 8mm cameras in the late 50s but had to devise their own mount with a longer flange depth than the 8mm D-mount, and have custom lenses manufactured by Angenieux and Som Berthiot. Beautifully built cameras by the way, worth examining if you're devising a new version. Nizo and Beaulieu were the only other companies I know of that copied the guillotine reflex mirror system. Nizo used fixed and optically adjusted D-mounts with an extended flange depth while Beaulieu managed to squeeze the mirror within the D-mount standard FFD of 12.29mm for their standard 8 cameras. For Super 8 though they moved up to C-mount.

     

    The standard focal length for Super 8 is about 15mm which sort of precludes the use of most larger format lenses for anything other than telephoto, so I'm not sure a relatively expensive intermediate mount system like the P&S Technik one is worth the trouble. There is also the Eclair TS intermediate mount as used on the ACL which does the same thing, but it makes more sense for 16mm.

     

    Dom, thanks for this great info!

     

    Just for examples,

     

    the Soviet "Meteor" zoom lenses specially made for the Krasnogorsk-2, 3 and 4 cameras have long rear element protrusions from the end of the M42X1 thread mount on the bodies, if you compare to the ZENIT 35mm still lenses.

     

    The COMPUTAR CCTV 1/2 and 2/3 manual zoom lenses in C-mount have very short protrusions (almost none).

     

    Beaulieu guillotine mirror system:

    u4r1.jpg

     

    Nizo Super 8 cameras should utilize the beam-splitting prisms, 'cause the serious models have the fade/overlap capabilities via their shutters:

    84la.jpg

  14. Because I don't wanna be stuck with normal lenses at best and I'm not a millionaire. Most C-mount lenses were made for a much larger format size than Super8, which is why being stuck with C-mount lenses makes it much more expensive to be able to use a comparable field of vision rather than what's mostly long lenses at the format size that we're working with.

     

    And that's exactly why it's a great idea to offer different mounts for a new camera (maybe via co-operation with P + S) with such a tiny format size that most C-mount lenses weren't even made for.

     

    (Please don't understand me wrong. I have nothing personally with you, and here is not the correct place, if any.)

    I have respect all your ideas, and this forum is a great place sharing thoughts...

     

    I didn't mention you in my CS-mount post as you see... You can do everything what you want, even disassemble the elements of a lens and make an invention. All are great and creative things.

     

    By the way, companies don't recommend the CS on a C-mount equipment in their technical literature. Also, you can find 2nd hand great reasonable priced C-mount lenses like new, you don't need to be a millionaire... Using C-mount lens will be perfect on a Super 8 camera as having large element diameter...

     

    (By the way, I work in this industry as a professional and an amateur for myself (occasionally) for more than 30 years... Have been with many award-winning engineers, and filmakers before. Do you remember telling me about the boom operator having 30m cables? In my some sets, the sound team has two big cases of equipment and 30m cable is nothing for them. There, I was trying to tell for a much simple way with min. requirements)

  15. Many CS lenses don't produce sharp images at all on a C-mount. The focal plane will never be on the film due to a retro lens and a back focus plane which is in a fixed position. I.e. rotating the focusring doesn't alter the position of the rear lens. It only adjust the front and/or inner lenses.

     

    Exactly Andries! Thanks!

     

    What I am trying to tell to the people is that!

    I never tried it, cause there is no need as many C-mount lenses are in reasonable prices...

  16.  

    And yet another problem I've come across now: Almost all C-mount-fitting CCTV lenses (as they have been designed for a format size almost idential to Super8) are in fact CS-mount (and all lenses that are C-mount rather than CS are even more expensive). The mount itself is identical, but the focal point is way different. With a C-mount camera and a CS lens, what you get is a macro lens: Everything beyond, say, 5 or 10 cm away from the lens is all a blur.

     

    Then again, I guess this could work with any wide-angle converters that require macro ability. Mount the CS-mount CCTV lens on your new C-mount camera, then use a wide-angle converter requiring a macro lens, and there you have your working lens.

     

    Still, C-mount seems a rather awkward choice nowadays for a format that's pretty much identical in size to 1/3" CCD video cameras.

     

    Yes, the CCTV lenses are offered in both of C and CS! and you cannot use CS-mount lens in a C-mount camera, pictures will be out of focus as you said. Their flange focals are different!!! C-mount is 17.526mm while CS is 12.5mm.

     

    I have used the COMPUTAR C-mount CCTV zoom and fix lenses with manual focus/aperture and zooming (I have several) in my eclair ACLII 16mm camera with success, despite I have several pristine Angénieux zooms in CA-1 (eclair) mount.

  17.  

    But what if you, say, have shot 20 carts on a professional production with many outtakes? Wanna spend 10 hours just on synching?

     

     

    Firefighter? Boom operator carrying 30 meters on their back? The way I know shootings where very long cables are required, they usually cover the floor, and the cables themselves are covered in rubber matts. Any shorter distance, just use shorter cables! I don't know any shoots where the boom operator really has to carry tons of cables on their back.

     

    Oh thank you!

    I don't know how and what a boom operator carries...

  18.  

    Well, why would the boom operator be that much away from the camera? So far it sounds like this is gonna be the most silent Super8 camera ever, and XLR cables can go a long way, like 20, 30 meters or more. And for any other cases you use radio. You yourself confirm how rare any case is where you can't use XLR *OR* radio if it's only once in 20 years and more than 50 countries. Even then, there's still the wi-fi antenna that I guess could even be used to receive a sound signal.

     

    Yes, Benjamin you are right, too...

     

    But my sound-man is not a firefighter anymore carrying 20, 30 meters or more cable... Those days must stay in the past of Pilotone recordings!

     

    I told before, we are talking about the more possibilities for this new camera...

  19. Just how linking 2 1/2 minutes of audio to the equally linear video footage is seen in any way as a 'problem' is hilarious.

    I often have documentary audio recordings made along with the HD footage and then sync each clip/shot with ease in Premiere Pro, Final Cut Pro or Avid Media Composer (which I've been using for over 20 years).

     

    2 1/2 minutes would take all of twenty to thirty minutes to sync at most.

     

    Thus having learnt to edit on a six plate Steenbeck, with my film clips all dangling into a big bin, a mass of mag stock full of my audio recordings, whilst clutching a chinagraph pencil and a CIR splicer at the ready; I find it utterly incredulous that anyone would find syncing 2 1/2 minutes of sound in this day & age daunting in any way. = This is what a clapperboard is for. :rolleyes:

     

    You are absolutely right Bill!...

     

    But may I am dreaming of snapping on magazine to my camera accepting the rolls of Super 8 in Bulk (on core), too. Think that: you have two separate mags for S8 cartridge - 50ft., and S8 roll - 238ft...

  20. Whether you record sound on a separate box, or on the one provided by the camera, it makes no difference to workflow. You will still have to manually manage how the film and sound are eventually married together. That's quite normal or familiar practice in film making.

     

    The only other solution, not provided, is recording directly on film - but short of that I don't know how this camera, in terms of sound, would differ from any other film/sound workflow. The only difference is that the sound recorder is built into the camera. Other than that you do sound in more or less the same way it's been done since sound film was first invented.

     

    C

     

    Yes Carl,

     

    Thanks for the possibility info...

     

    Film technology didn't change much, but the digital workflow and equipment for audio. Do you remember the MiniDiscs? What will do if the SD cards are obsolete in the future?, but you can change the sound module in a very easy way. The pro manufacturers just began to think this possibility like in ARRI Alexa cameras, now they are totally hardware upgradeable...

     

    We will gonna pay an amount for that camera I am pretty sure...

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