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Erkan Umut

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Everything posted by Erkan Umut

  1. Lasse, The term oscillating confuses me, is it rotating mirror shutter (360°total, inclined at 45° relative to the aperture). As far as I know, oscillating is used for a mirror body (the mirror inclined at 45°) connected to off-center (eccentric) disk to give the left right or vice versa movement...
  2. 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!
  3. Carl please try not to give further mathematical examples and be simple. There are not engineers only among us... Many thanks!
  4. 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...
  5. "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."
  6. 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.)
  7. 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.)
  8. 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?
  9. 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...
  10. 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.
  11. So, what I think is, to be able to get the same FoV (AoV) on a S8 camera with a lens designed for 16mm format, that lens could be placed closer to the film/focal plane theoretically (not in practice). (?)
  12. What a simple and yet well enough description... Many thanks!
  13. This is from David Cheshire's Book translated to Dutch I think... I have in English (The Book of Movie Photography) and German (Filmen). Highly recommended to all!
  14. 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...
  15. 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?
  16. 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.
  17. 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: Nizo Super 8 cameras should utilize the beam-splitting prisms, 'cause the serious models have the fade/overlap capabilities via their shutters:
  18. (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)
  19. Exactly Glen! Why stuck with the CS mount while there are many C-mount lenses around?
  20. 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...
  21. 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.
  22. Oh thank you! I don't know how and what a boom operator carries...
  23. 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...
  24. 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...
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