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richg101

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Posts posted by richg101

  1. Fixed EF mount is a disastrous choice.  Infact the lack of m4/3 mount option from RED and BM on their Ursa is a mystery as well.  When you give users the ability to stick a SB ultra or SB XL on the camera you open up vast cost effective optical options.  A m4/3 to PL / oct19, oct19, etc etc adaptor would also allow use of cheap LOMO s35mm primes.

     

    Exactly the same mistake BM made with the first cinema camera EF version.  Everyone wanted m4/3!   

  2. Hi, all! 

    Has as anyone found any good wide angle adapters for Kowa 16-H/8Z? It's one of the wider projection lenses (50mm ff taking lens if cropped to 2.40:1), but it doesn't quite get that Hollywood wide anamorphic look. I've been looking at the Dog Shidt Optics FF38, but I'm not sure if it would work to put the projection lens between the ff58 and the ff38 wide angle adapter front end.

    unfortunately the ff38 has a rear element clear aperture of 36mm, So puts some limitation on its use with anamorphic lenses.

     

    the ff38 has been designed to fulfil near transparent afocal optical performance when used on a 36mmx24mm sensor area on a 58mm/f2 aperture. Being over engineered it does infact cope with as wide as 50mm,f1.4 apertures without significant light transmission loss or vignette on 36x24mm sensors.

     

    50mm taking lens plus a 2x ana on 36mm sensor width cropped tp 2.4/1 is approximately similar to a 35mm spherical taking lens on a 36mm wide sensor area cropped to 2.4/1, so using a ff38 on the front will likely produce vingette too harsh to make the expense and extra weight/length worthwhile.  I'd played around with making scaled up ff38's with 50mm rear elements but 95% of users don't realised or value how hard it is to manufacture a wa attachmant that does what the ff38 does, and as such a £500-600 price point aint viable

  3. It does seem that the actual gap between this ($30,000) and the A7Smk1 (currently $1500 to buy new) is small.  Their footage doesnt look very good.  Their lens mount is a hindrance since it limits the use of specialist lenses with short back focus distances.  

     

    The actual industrial design is rather nice though, and I imagine this will do very well with underwater shooters who can't live with the pitfalls of the a7s.  This could infact be the perfect match for FORBES70 as it happens.  Body will sit quite nicely into a slightly reworked FORBES body, and the clean look from 100,000iso will be good to combat the inherent slower lens speeds of medium format lenses.

  4. huge upgrade specs wise on paper.  but there is nothing here that makes me want to sell up the a7s and pay the huge euro price on this new model.  fullhd from the a7s leaves nothing to be desired in res terms.  we didnt need 4k. we needed 4;2;2 and 10 bit internal.

     

    the upgrade from the a7r mk1 to the a7r2 was justified due to the flawed video mode on the a7rmk1.  And the IBIS and repositioned shutter button for still photograophy  

    an upgrade from the a7s mk1 to this seems like a waste of money for me since very few lenses with good aesthetic for motion picture also deliver 4k onto full frame.  .

     

  5. Do you think the DSO tele/wa converter fronts will work with the Kowa? They look pretty large.

    for a 2.40;1 delivery (ie, cropped sides of a 16:9 sensr)...

    ff38 and ff88 attachments will support taking lenses as wide as 50mm on full frame 16:9  so will do 35mm lenses on aps-c and 25mm lenses on gh4, or maybe as wide as 21mm lenses on gh4 4k mode.

    from this, I'd imagine with a kowa between the taking lens and the ff38 or ff88 you'll be needing a 100mm on full frame, a 70-80mm on aps-c and a 50mm on gh4 (45mm on gh4 crop mode).

     

    multiply your focal length by 0.66x for the FF38 and 1.55x for the FF88.

     

    FF38 has a clear aperture on the rear element of 36mm meaning transmission and aperture should be ok for 2x anamorphic f2.8 on full frame, f2 on aps=c and f1.4 on gh4,  The whole optical pathway becomes ridiculously long however.  

     

    There may be a possibility of a run of FF38's 'scaled up' to 50-60mm rear elements and an associated wider fov, but would be extremely expensive - but very similar to the custom lens Kubrick had made for his zeiss 50/0.7.  As it happens, the FF38 was influenced by the WA design kubrick had!

     

     

     

  6. Unfortunately I think you might do well to look at high quality flare overlays rather than risk shooting anamorphic last minute.  Unless you can budget for a nice and clean 35mm lomo squarefront and the required rigging.  There are not really any offerings apart from the SLR magic that flare similarly.  

     

    On the flip side, and i don;t like plugging dso here personally, but I would actually suggest a trump58 and trump38 in combination with a speed booster.  a few nifty oval apertures, with the intention of overlaying the horizontal flares in post.

    password= trump

     

    Being in the UK, I could rent you a TRUMP body and attachments for a few days...

  7.  

    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.

     

  8. 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).

  9. 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.

  10. 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.    

  11. @richg101 I thought you'd be the only one on this board all over this and probably even buy one, using Hasselblad/Leica/Mamyia/Contax Medium format glass  on a 45mm sensor wide

    *Edit: What is the effective sensor size of your Forbes 70mm?  (I know it's s16 but I mean the effective size after glass conversion). This is probably tiny compared to that, its 45x30mm. 

    The Leica is recording HD on a 45x25.3mm size image exactly at 16:9

    A Fullframe is recording on a 36x20.3mm  size image exactly at 16:9 

    A s35/APS-C is recording on a 25x14mm size  image give or take at 16:9

    So it's not a small difference, FF is about 10mm wider than APS-C, and the Leica is about 10mm wider than FF.  

    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):(

     

     

  12. 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   

     

     

  13. It's really doable with the decent stabilization, but you have to hold pretty still.

    Shooting 1/4 25 fps and then speeding up in Resolve 400% (as I haven't figured out yet to speed it up 500%). Still trying around, though.

    Well, we have to go back to old techniques to get some freshness going. :d

    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%.   

  14. Might be so with a mechanical shutter, but we don't know what exactly is going on with an electronic shutter, do we? There's software involved and it's hard to know what's being done in camera, there might be some magical readout mojo going on which you might not be able to emulate in post.

    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. 

  15. 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.  

  16. There is no such thing as slowing the shutter speed lower than 1/framerate. It's a physical impossibility. Shooting at the lowest video standard frame rate available (23.97p), the lowest shutter you can achieve is 1/23.97s. 

    If you want to go for a slower shutter speed, then you have to go for a perfectly matched slower frame rate. 

    For example when you choose 1/4s shutter in 24p, your camera is lying to you, it's shooting at 4 frames per seconds not 24p.

    I just wanted to make that clear. 

    Shooting at a lower frame rate is exclusively timelapse shooting when conformed back to normal frame rate, it's the opposite of slow motion where you shoot at a higher frame rate and conform back to lower.

    Any one here with a camera that shoots stills and has timelapse ability or have an intervalometer can achieve what you're discussing here. Shoot 1/4s exposure stills in timelapse mode and you get it. You can even go as low as 1 second shutter and thus be effectively shooting at 1fps. 

    Also another option is any canon DSLR with ML installed. You can exactly achieve what the sony's are doing by going into ''frame-rate override" and setting it as low as you need say 4fps, then if you go to the exposure menu you'll be able to go to 1\4s shutter. If you record that, the camera shoots 4 1\4s exposures each second, in ML you can actually go much lower than sony and shoot 5 second exposures (at that you're shooting something like 1/025 fps) and as a bonus in Canon DSLRs it actually conforms the file internally to 24/25p and you end up with a timelapse video just as if you used stills mode and did proper timelapse.

    I use it all the time when I want to create timelapse in-camera fast, but if I have the time I'll go the stills way for 4-5K resolution and raw/jpeg quality. 

    Anyway shooting at 24p, 1\24s is minimum. Going lower shutter/frame rate is timelapse/undercranking and going higher is slowmotion/overcranking.

    (over and under cranking is a term from the film cameras days where we reduced the frame rate by driving the film reel slower with crank to get timelapse and overcranked the film faster than normal to get slowmotion, you're doing the same thing but with more control and digital percision)

     

    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. 

  17. its kaylee one word lol

    ok i checked: on my rx10m2 shutter goes down to 1/4sec for 24fps like rich said, BUT it only goes down to 1/120 in 120fps 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. 

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