richg101

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About richg101

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  • Website URL http://www.dogschidtoptiks.co.uk

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  • Gender Male
  • Location Bristol. UK
  • Interests Designer, Photographer, Musician, Film Enthusiast

richg101's Activity

  1. richg101 added a post in a topic Most affordable cameras that work well for 2x anamorphic?   

    EXACTLY!  One of the reasons anamorphic is the go to for a true big budget looks is because it tends to only be advocated by the best DOP's, with enough professional brunt to demand shooting in anamorphic, and dedicating greater budgets in doing so.  Watch how each shot is framed in Django, Casino, Inglorious Basterds, etc.  They've been perfectly frames on set.  the set is moved to accommodate the desired frame.  Its been so meticulously crafted to accommodte for the limitations of optical resolution of the wonderful panavision anamorphics that even if they switched to spherical at the last minute, selecting wider FL's to suit a post crop, the image would have almost the same power as with the anamorphics due to the production value the meticulous shooting process adhered to and demanded by films who can afford to shoot 4 perf anamorphic.
     
  2. richg101 added a post in a topic Slowest shutter speed in video mode   

    FFS.  how about rather than debating something that benefits no one, and is impossible to debate without knowing exactly what's happening inside the camera, why not go and shoot something and benefit from the feature.   It's shooting 24/25p, and with a shutter speed of 1/4 or 1/5th of a second.  That's whats on the screen, so that's what's happening.  The engineers at Sony know more than anyone here.  Canon limits the shutter speed to 1/30th in video mode.  Sony limits to 1/4th of a second.  whether its 25fps with 5 frames duplicated, or 5fps, the result is EXACTLY THE SAME when conformed (sped up) to a smooth motion (600% in 24p/1/4th or 500% 25p/1.5th).
  3. richg101 added a post in a topic Looking to get back into photography.   

    Rent an A7S and the 55mm/1/8.  take the time to get used to its controls.  buy the user guide to learn how to set it up properly.  It's a true photographers camera without the need for a flash, that shoots video.  once you;re used to it, you'll never look back.   ideally invest in a nice leica RF lens and go full manual focus.  AF is for sports and point and shoot.  IMO if you need AF for anything else, you need to learn how to manual focus.
  4. richg101 added a post in a topic Most affordable cameras that work well for 2x anamorphic?   

    I'd be inclined to suggest going full frame (a7s or a7r2 (or even a 5dmk3 raw hacked)), Even 1080p full frame, cropped to 4:3 and losing horizontal sensor resolution will outperform smaller sensors shooting 4k with most lens options.  there are no anamorphic lenses that shoot with exciting apertures and that also resolve 4k resolutions on sensors as small as the sensor area the gh4 uses in 4k 4:3 mode.  INFACT, most down even resolve 1080p onto a 4:3 provided by the gh4.   I'd sooner shoot full frame, cropping the 16:9 unsqueezed image, and making use of a proper frame height and the associated fov and dof you need for anamorphic to be worthwhile.
    I think the a7s immaculate oversampled internal 1080p full frame mode (and associated DR, small file sizes etc), and a 2x anamorphic, cropped to 2.4:1 and losing 1/3 of the horizontal res is way better than pointless extra resolution where most lenses dont deliver anyway.    
  5. richg101 added a post in a topic First footage from Leica S (Typ 007) Medium Format   

    Forbes70 uses a 65mm x 36mm image pickup area, meaning lenses like hasselblad, mamiya, bronica, rollei 6000 etc lenses are used to their full capability.  (They have 80mm image circles to cover 6x6 (56mm x 56mm).  I'm currently working to take the image pickup to around 75mm wide, at 2.2:1 aspect ratio (cropping the vignette and losing vertical resolution), however this is only really viable when a suitable 4k head arrives.  (13 stops, low rolling shutter, 10bit or more).
    The problem with this new Leica is that the sensor limits it's use to native lenses.  hassy, etc are pretty useless since no wide options are present - for wide you need 40mm on 56mm wide sensor.  with a 45mm wide sensor you end up with the hassy 40mm being a 'normal focal length'.
    It's a bit like how when using ff glass on m4/3, everyone moans there are no wide and fast options.  
     
    I guess my annoyance comes from the fact that every digital MF manufacture seems to be copping out with 'almost medium format' options, and then marketing them as medium format.  it would be like canon marketing aps-c as a replacement for 135mm film and never bothering to release a full frame dslr.  The only manufacturer of proper digital medium format systems went bust recently (DHW / Rolleiflex), exactly because of the bullshit marketing of the likes of this type of camera.  If people weren;t duped into thinking they were getting real medium format, the guys selling the real medium format stuff for the same price would not have gone bust.  there is now not one manufacturer making camera systems or lenses that fulfil true 56x56mm digital photography.  And the likes of phase one now know this so wont bother investing in full frame MF, and instead fulfil the new benchmark - 45mmx30mm (and smaller when the 16:9 crop happens)
     
     
  6. richg101 added a post in a topic First footage from Leica S (Typ 007) Medium Format   

    when sensor size is only a little bigger than full fraaem, I'd be inclined (forced due to not being able to afford the leica) to go full frame and an otus 85mm instead of this and the 100/2.
  7. richg101 added a topic in ANAMORPHIC   

    Iscorama rehousing plans
    Hi Guys.
     
    I'm actually in the process of designing the mechanical focusing section for OLIVIA-SCOPE-1.5x since current glass prototype is fixed at infinity in order to get the cylindrial section perfect before moving onto the simple and easy spherical focusing optics.
     
    One thing I do know is that the amount of focus throw, and spacing of elements is going to be very similar to the optic spacing in the Iscorama, from 4ft to infinity (around 10mm), so I am currently designing the mechanism to shift the huge front focus element back and fourth.
     
    Here's the cool thing...  I'm going to be manufacturing the focusing mech as a scaled down prototype to test its function, before making something that costs around £250 worth of brass alone for the full size unit.  I'll be designing the miniature mock up to fit the current elements from the Iscorama 36 and pre 36 (since I have one here).  
     
    So there may be the possibility of offering a limited run of isco 're mechanising' to existing Iscorama users who are not willing to leave the 'rama platform and it's compactness and low weight.  
     
    So, the focusing mech/rehousing will provide 3.5ft-inf focus, with hard stops at each end.  non rotating front element, with a profile 82mm filter thread, minimal added weight, focus gearing (where gears dont rack back and fourth during focusing),  the rear element willremain protruding to allow for deep seating into the front recess of a taking lens, and probably have some type of rail support.  Pretty much everything the original Van Diemen rehousing should have been.
     
    When it comes to manufacturing, I'll likely have a few mechs made.  it'll be a one off run at this size, and am expecting the cost of the mechanism as well as rehousing of a supplied iscorama to be in the region of £500-800.  So if there are Iscorama 36 / pre 36 users who might be interested please let me know so i can hit you up at time of manufacture and see if you want me to have some parts manufactured.
     
    R   
     
     
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  8. richg101 added a post in a topic Slowest shutter speed in video mode   

    the technique seems to hate fast camera motion since with camera movement everything is moving, whereas, with locked down shots, the static objects are sharp, and the moving ones have a blur trail.  you might wanna try 1/8th of a second for handheld, then only speed up by 300%.   
  9. richg101 added a post in a topic Slowest shutter speed in video mode   

  10. richg101 added a post in a topic Slowest shutter speed in video mode   

    exactly.  It's obvious that a mechanical shutter can't have a longer exposure than 360degrees or the full length of the frame.  It may be a wrapper, I couldnt give two hoots really, I see on my camera 1/5th of a second.  the electronic shutter is open for 1/5th of a second, then closes, exposing 5 frames at a time.  it could be that its 5fps/360degree but for the purposes of this topic, for the final time, as far as I am aware the Sony cameras allow the slowest 'shutter speed' to be selected during video mode.  the effect cannot be achieved without this setting. 
  11. richg101 added a post in a topic Slowest shutter speed in video mode   

    the fact remains that Sony allow the slowest shutter speed in video mode.  1/4 of a second.  the setting is there, in plain view.  if it was shooting at 5fps it wouldnt say 25p, it would say 5p.  what ever it's doing, its doing what i imagine the thread starter is trying to find out.  the rolling shutter is open longer than the frame duration.   I keep expecting Sony to prevent users going slower than the frame rate, but it keeps being left in to our benefit.  
  12. richg101 added a post in a topic Slowest shutter speed in video mode   


    You're mistaken.  sony cameras are shooting 25p (25 individual frames per second), it just so happens that the sensor is gathering light for 1/5th of a second then closing, then gathering light for another 5th of a second, five times a second.  each 5 consecutive frames are the same.  if it was shooting just 5 frames per second, when I open the file in premiere i'd see 5p, but I instead see 25p meaning there are 25frames there.  there might not be 25 different frames, but I have 25 frames none the less.  Tell me one mirrored camera that can shoot continuously for 25mins at 5 frames a second with each frame exposed continuously without a gap.  it isnt physically possible to open and close a mirror that quickly, continuously for 25mins regularly.  even a 1dx or d4 will eat up its shutter count and mirror will be dead in 2 months.  with the a7s you can shoot these clips at 4k, speed up by 500% and you have a timelapse with a rather interesting motion blur created practically, and in small file sizes. 
  13. richg101 added a post in a topic Slowest shutter speed in video mode   

    for this technique you want less frames per second.  Shooting at 120fps means you will degrade image quality for no reason since each frame will be sharp, and low light benefits no longer apply.
     
     
     for instance, 25p at 1/5th of a second confirms perfectly when sped up to 500% since the 1/5th shutter equates to 5 frames being exposed with one image.  hyperspeed by 500% smooths as if it were 25fps.  
     
    shooting 24p and 1/4 sec means you need to speed up by 600% to keep the perfect conformation.  1/4 x 600% = 1/24th sec or 360degree shutter.
     
     
     
    this was shot on the humble NEX5n, more than 3 years ago at around 400iso i think.  imagine how clean the a7s would be when in this mode. 
  14. richg101 added a post in a topic Slowest shutter speed in video mode   

    Sony allow as slow as 1/4sec at any frame rate.  shooting at 25p and 1/5th sec then speeding it up by 500% gives beautiful low light results for timelapse type stuff.  with the motion blur which is very pleasing for thing slike cars in the dark.  
    https://vimeo.com/52579247 
     
  15. richg101 added a post in a topic Seeking Info About the B&H Projection Lens   

    Yo Bold, Tito, etc.  
     
    for better centralisation of the front optic I suggest using circular cross section rubber o rings.  it appears Bold had to use quite a thick piece of rubber on his.  maybe select a helicoid smaller than 58mm so its' closer to the diameter of the 45.95mm diameter of the element.  looking closer, mine is actually a m52 helicoid!, meaning i only needed a rubber o ring of 3mm thickness to go around the element.  so a 45mm internal diameter o-ring of 3mm thickness would have been the perfect fit for an m52 helicoid.  it appears bold requires a 45mmid x 6mm thickness, which might be hard to find hence why he needed to fettle down something to fit.