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richg101

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Posts posted by richg101

  1. I have a feeling they may be doing something clever with the dual batteries - with the amount of pins on the grip I highly suspect that as well as the protocol to send data about when a button is pressed etc, as well as the battery charge status, and the intelligent 'use the lowest charged battery first system'.  Firmware could be written to take feed from different pins to get more voltage to the voltage regulator, then tell the regulator to send a little more voltage than normal.  they could use 3 cells instead of the usual two, alternating between them in order to make sure no one cell gets discharged more than the other 3.

     

    Either the firmware is doing something like this or is literally putting a slower timer on the overheat warning -pushing things a little further than they should and letting things let a bit warmer.  If it is a clever higher voltage system then the camera will need to detect a authentic grip with a pair of batteries in there   

  2. Thanks for the heads up!  I expect since the battery grip could very likely be firmware controlled and set up to feed the camera with moderately more voltage, the sensor could be made to run cooler due to lower current/resistance.  lower running heat translates to even lower noise levels!

    Irritatingly the birdcage i just grabbed won't permit use of my battery grip and I was about to sell the grip.  I might end up chopping the grip up and routing the wires to a satellite dual battery pack to benefit from this update!

     

     

     

     

     

  3. It all becomes moot when you consider why a user would shoot 35mm rather than medium format.  It's all about cost and compactness.  Otus is a doubling of your investment of a 5ds or a7rii, for a 'normal lens' of 50/1.4.  

    very few dslr users will think it viable to invest in the Otus lenses and a d810, a7rii or 5ds (which do get you very close to medium format).  If they do, their camera system becomes heavier and more cumbersome than a phase one system and the difference in price isn't as much of a factor (even if investing £20+k in a new setup (usually on a lease).  you can get a phase one camera with a 80/2.8 and a outdated 40mpx back for the same price as a 5ds and an otus, with 16bit colour (which actually makes the 40mpx more powerful than the 50mpx of the 5ds).  

     

    The debate here is coming from those who wont ever have the need for an otus and a 5ds in either their professional or hobbyist endeavours.  Why bring them into the equation?    

     

    The fact remains that assuming this adaptor doesn;t degrade the iq (and compresses the image circle down in a lossless fashion), users of the a7rii and a good MF lens like a pro quality 80/2.8, they'll have a lens of similar quality (resolution, fringing, distortion, frame illumination uniformity) to the otus 50/1.4.  get a good 80/2.8 for £300-400 and this adaptor and you have a sub £1000 otus setup. 

    Unfortunately I doubt the optical designers, and the manufacturers of this unit are at the level of that from zeiss, who left no expense spared on the otus line.

     

     

  4. The hasselblad planar 80 2.8 isn't sharp either wideopen, it shines @5.6-8, @2.8 it's just another lens. The best 80mm is the mamiya 7 80 4, but you can't mount that on a speedbooster because it's a rangefinder lens.

    The Planar I am refering to is the later CFE unit, without the shutter.  From my experiences this delivers superb imagine quality at f2.8.  It's sharper than all of the 85mm lenses I have for 135 format.  it outdoes the zeiss planar 85/1.4 at f2.8 (closed down 2 stops), The modern hy6 Xenotar 80mm/2.8, my sonnar 85/2.8, my oly 85/2 at f2.8,  it almost matches the xenotar 80/2 at f2.8.  'Just another lens' it is not!  Hence why Hassleblad have ruled supreme in medium format for so long - the 80/2.8 planar is astounding.  Infact, I was informed by mart mueller during my research into lenses for FORBES that during development of IMAX 15/70, they went through every available medium format option and the hasselblads were the only ones that met the grade.   

  5. Hey @richg101, have you tried the Mamiya 80mm f/1.9?

    I had one briefly while sampling various mf lenses before deciding on a planar 80/2.8 for Forbes.  It's a good lens, but at f1.9 it's not quite good enough IMO.  Only when at 2.8 does it start to get refined (as in, that refined tack sharp look you get from a hasselblad 80/2.8.  the only 80/2 that I've tried that comes close to a good 80/2.8 is the Xenotar for the rollei 6000 series, and even that falls short.

     

    Obviously I am coming into this discussion purely with relation to the resolution gain from this new kipon adaptor.  I am looking at it simply as a way to obtain the superb iq by compressing an image from a good 80mm onto a smaller frame and having a resultant 50mm lens that outdoes a 50mm for 35mm format.  

    I am biased due to being a 6x6 80mm+ image circle man rather than a 645 70mm one.  If you compare the 80/1.9 vs a planar 80/2.8 on a 645 back you actually won;t see much difference in exposure - certainly nowhere near a stop difference.  and the sharpness at f2.8 on the planar actually makes the dof feel shallower due to the ration between in/out of focus being so much more.

    Are you sure? There is a lot of empty space inside my Pentax 645 to Nikon F adapter. 

     

    the focal reducer needs to be placed as near to the sensor as possible otherwise it needs to be made a lot bigger - so big it wouldnt fit in the mirror box.  your ffd is also reduced by approximately the same as the magnification of the focal reducer so if your using a 0.7x reducer, the ffd reduces by around 0.7x     

     

       

  6. The fastest? Not really... I've got a whole bunch of faster ones sitting here.

    Here's a complete list of fast medium format lenses:

    Fairchild 75mm F/1.9
    Zeiss 125mm F/1.5 Sonnar
    Zeiss 85mm F/1.4 Planar
    Ernostar 85mm F/1.8
    Ernostar 125mm F/1.8
    Aerojet Delft 64mm F/1.8 
    Aerojet Delft 70mm F/1.6 
    Aerojet Delft 75mm F/1.7
    Aerojet Delft 100mm F/1.4
    Aerojet Delft 112mm F/1.4 
    Aerojet Delft 150mm F/1.5
    Aerojet Delft 300mm F/1.5
    Delft Rayxar 105mm F/0.75
    Delft Rayxar 150mm F/0.75
    Delft Rayxar 250mm F/0.75
    Perkin Elmer 75mm F/1.5 
    Perkin Elmer 150mm F/1.5
    Perkin Elmer 300mm F/1.5
    Wild Heerbrugg 98m F/1.4 
    Wild Heerbrugg 98mm F/1.0
    Wild Heerbrugg 250mm F/1.8
    Farrand Optical Super Farron 150mm f/0.87

    Leitz Elcan 100mm F/1.4
    Mamiya 80mm F/1.9
    TTH 100mm F/1.8

     

    veocr5.jpg

    all of which either lack usable iq at their widest aperture, and in some cases don;t even have an aperture, are completely unusable due to requiring huge outlay on bespoke remounting, are heavy, are coated and or glass selected for for b+w only, and have colour fringing issues so bad they need to be used in B+W only, or as pointed out, have ffd's too shot to permit focal reduction.  Not to mention most of those lenses lack basic function such as a focus mechanism since all are designed for infinity from high altitudes.

    when we're talking medium format 'speed lenses' for focal reducer use that are adaptable, accessible and have basic featurs such as aperture and a focus mechanism on full frame cameras there are very few that will deliver the resolutions required to make the endeavour and expense worthwhile.

    1. Hasselblad 110/2 - at f2 this thing matches a 135 format lens for resolution, but has a 80mm image circle.  compressing this down by 0.7x almost doubles the resolution onto a FF sensor, while still using the best area of the image circle.  this hassy could be compressed by 0.5x without running out of image circle for full frame.

    2. Rollei 6000 Xenotar 80/2 - as above

     

    3. a few ultra projection lenses for 70mm film.  which can be fitted to an off the shelf helicoid and are sharp wide open

     

    There are no other medium format lenses that fulfil all of the basic criteria while delivering the base IQ required to make it worth going for a MF lens rather than a fast 135 format lens.

     

     

     

     

     

  7. One thing that we have to do with high resolution digital sensors is forget about the hyperfocal distances. They exist from the film days where print sizes depended on film size and should not be used today when critical focus is important. Just focus on the object that you want very sharp and adjust your aperture to extend the acceptably sharp objects. 

    Here is a nice article:

    http://www.northlight-images.co.uk/article_pages/hyperfocal_distance.html

    I disagree.  learning and having an idea of hyperfocal distance is very important to camera users - particularly for documentary and observational/fly on the wall film making.  there's in focus, and there is 'acceptably sharp'.  I'd much rather get a shot that's acceptably sharp over the required field, than not get the shot at all due to messing around backing and fourthing to get one aspect perfectly sharp, by that time the subject has clocked they're being captured and the shot is ruined.

    Our eyes don;t like seeing everything in focus anyway.  it looks nasty.  at f8 on the widest setting on the rx100, i'm certain focusing at 2m will mean everything from 1m-infinity is 'acceptably' sharp.  it'll only be bang on at 2m, but the rolloff should be slow enough to make the entire frame usable in regards to illustrating what you're trying to show.

     

  8. http://www.ebay.co.uk/itm/Camlink-TPVIDEO1-Pro-Video-Tripod-Double-Pan-and-Tilt-Fluid-Head-Carry-Bag-/400867049618?hash=item5d5589c092:g:xlYAAOSwEeFU5ctf

     

    superb, heavy tripod.  avail for less than $150 on ebay US I imagine.  Just search 'Fluid head tripod' on ebay and you'll see them pop up.

    I've had one for around 6 years.  i had it around 5 months and the rivets died on the spreader.  these were easy to drill out with a 4mm drill bit.  I then replaced the rivets with some m3 bolts and some locking nuts.   if you grab one of these then replace the rivets before they break you'll never look back. - 30mins work to swap the rivets for some stainless m3 bolts.  

    http://www.ebay.co.uk/itm/M3-M4-M5mm-A2-Stainless-Steel-Machine-Screws-Slotted-Pan-Head-Bolts-/150863410183?var=&hash=item232028f407:m:mgDxTbKl1z2ODx5iv040BHA  some m3, 30mm bolts will do it.    

     

    http://www.ebay.co.uk/itm/A4-Marine-Grade-Stainless-Steel-Nyloc-Nylon-Insert-Locking-Nuts-M3-4-5-6-8-10-12-/360650014234?var=&hash=item53f86a7e1a:m:mO7ApJ-con6PbvWHpFurl-g  m3 nylock nuts.

     

    http://www.ebay.co.uk/itm/A2-STAINLESS-STEEL-FORM-A-FLAT-WASHERS-TO-FIT-METRIC-BOLTS-SCREWS-M1-6-TO-M30-/150802639052?var=&hash=item231c89a8cc:m:mAdvuPIIKGFCGZAWUgnX8gQ  washers.

     

     

    quick release plates are around $10usd.  

     

    it's got a mini bowl for quick levelling.

     

    ps.  it takes around 2 months for the head to become truly fluid.  at first it might be a bit graggy, but once it's been used a bit it smooths out lovely.

     

    so apart from the rivets on the spreader this tripod has nothing to go wrong and is lovely and heavy - perfect for dslr's

     

    pps.  I forgot to mention, I replaced the rubber feet on mine for some softer rubber feet (i used the type for walking sticks) since the ones on there from the factory were a bit hard and could slide on hard flooring.

    http://www.ebay.co.uk/itm/Walking-Stick-Rubber-Ferrules-Tips-Feet-Stoppers-Black-Choice-of-5-Sizes-/400887863108?var=&hash=item5d56c75744:m:m86f6CfsJQHFUwHkLERgBkQ  13mm should do it.  or bigger ones will go over the existing feet.

     

     

     

     

     

     

     

  9. As a general rule, the bigger the rear element of a WA adaptor, the poorer the IQ will be on bigger sensors.  A WA adaptor will be typically designed for a specific fov and a specific light transmission requirement.   If it does well on wide lenses it normally wont do well on tele.

    a smaller rear element on the WA attachment wont always result in hard vignette,  It'll simply reduce the light transmission.  hard vignette is almost never associated with the diameter of the rear element but more the field of view the attachment is designed to cover.  

     

    the best comparison is the Isco 30, Isco 36 and Isco 54.  

    the 30(pre 36) and 36 have no difference in fov capability.  but on Full frame the 36 will transmit 50/f1.4 and the 30 will only go to 50/f2.  the pre36 is moderately better IQ than the 36. 

     

    54 doesn't provide much of a increase in field of view either, despite being way larger.  However a 54mm rear permits transmission of a lot more light - at the expense of even worse IQ. - the 54 has worse resolution and colour correction than the pre36 and 36 so fringes more, but in non contrasty environments the advantage of being able to transmit over twice the light that the 36 can, it has it's purposes.

     

    Zoom through adaptors are Afocal meaning when attached to a lens set to infinity the focus remains at infinity.  Non zoom through usually have an effect on the focus distance meaning you can only use for closer shots.  This makes sense since typically a WA adaptor would be used in confined spaces.  IQ is also usually worse.   

     

     

  10. Agree. I actually emailed one of Sony's product managers back when I first got the A7S and suggested they offer a professional version of the A7S with Xavc Intra and a cfast media slot, and a body around the size of the 1DX.  Exactly the same camera, but aimed at being used alongside the F55 as a specialist camera priced at the same point as the FS7.  A full frame camera, that shoots stills, low light and that can be used on gimbal.   Back when the 1dc was 10,000£ and without an equal.  

    If Leica capitalised on the fact that they don;t have a cine division to protect, this could be a very formidable option for exotic gimbal/drone work where the Alexa Mini may be out of budget or still too heavy.

  11. exactly.  though I interchange from true full frame or aps-c with a 0.7x speed booster and get very similar dof/fov with both, i'd always go full frame if I could.  the intricate step between in and out of focus is a lot more refined from a larger sensor.  If there wasn;t a benefit, pro's wouldnt be investing £25k+ in Phase1's and 80/2.8's.  they'd be shooting full frame and 50/1.2., closed down to f2.  Also, I wouldn't have spent money developing FORBES70, building a set of good quality MF glass,  I'd have grabbed fast modern 35mm lenses and spent the money on going on an expensive holiday. 

     

    problem is, it's only the real pro's that realise that a MF 80/2.8 wide open has more refined defocus rolloff, and better overall performance than the canon 50mm L closed down by 2 whole stops! And the real pro's don;t have time to enter into this debate - their too busy shooting.  

     

    Roll up to shoot a automotive commercial with a 5dsr instead of a medium format setup and you'll be turned home by the creative director.

     

     

  12. unfortunately the widest the dso wa attachments will permit is 35mm on aps-c.

     

    Century make a number of multi element wide angle attachments.  their premium 'focus through' units are nearly usable and if things add up you might get lucky - they like wide taking lenses on smaller sensors, and hate long ones on bigger sensors.  if you can find a higher magnification unit (more than 0.7x) this will help.  generally the deeper the body of the WA attachment, the more elements, the better iq you;ll get

  13.  

    wait. please... im begging you. im freaking out rn. not being ironic here: > does this mean theoretical lenses which dont exist? with wider apertures than they normally have? talk to me like im 4 years old. i feel like i get this if it means, If lenses on my 35mm ff camera had wider apertures, they could give a medium format look for their respective fields of view 

     

    The benefit of a FF-APS-c speed booster is a lot greater since the availability of fast and wide lenses for FF is pretty good.  

    In medium format terms your point is very valid though since there are still limitations on how you could go about trying to replicate a 150/2.8 for medium format, when using a FF lens.  on paper you;d need a 105/2 lens for full frame in order to match a MF 150/2.8 and this 0.7x focal reducer (assuming the focal reducer is actually delivering good performance).  HOWEVER, you'd actually need a 105/1.4, stopped down to f2 in order to obtain both the dof/fov ratio as well as the image quality you can obtain from the 150/2.8 MF lens wide open.  There are NO 135mm format lenses that will replicate the balance of IQ and dof/fov that is achieved by a 150/2.8 on medium format.

    The OTUS line of lenses somewhat bridge the gap.  The new 28/1.4 at f2 on FF will likely outdo my Schneider SA 40/3.5 on 645 in terms of resolution, while providing similar fov/dof.    But at £3000 per lens they become less viable.  You can get 3 of the schneider 40/3.5's for the price on a single otus.  This brings an interesting point, in that if you look at the optical diagrams of the otus lenses they are infact not that far removed from a high end MF lens with a focal reducer stuck on the back.  

     

     

    again, please help me understand this. why is this so confusing to me?? ive shot medium format film but it was a looong time ago. today i feel like i have a pretty strong handle of sensor size in relation to depth of field in practice, and maybe this is a more theoretical discussion? like an "all things being equal" comparison??

     ? 

     

    Since OTUS lenses are the only real option for wide open shooting with superb IQ on FF, these would be the closest direct comparison against high end lenses on medium format.

     

    OTUS 28mm at f2 on the A7Rii will probably be a close match to a 40/3.5 wide open on a 6x4.5 frame of portra400, drum scanned. 

     

    if this focal reducer squeezes the image onto a smaller frame transparently then in some cases and with the best medium format lenses bought at good prices you'll have a poor mans OTUS.   

     

     

     

     

     

  14. You don't have to go for the hasselblad stuff, it looks like there will be a lot of mounts available. Most of the modern medium format lenses are pretty good, and hasselblads aren't even the best ones. 645 lenses are all very fast and designed for the smaller area, so they are  more useful, but you already know that :p

    Btw,anybody wants to trade a Nikon D3 for a sony A7s? :) 

     

    I think you may be right.  Contax 645 lenses will definitely yield more of a benefit from this than 6x6 hassy's.  Been examining that photo of the unit and the optical element doesnt look big enough to trasmit what would be required from the 110mm/2.   The 645 80/2 might be a little beaut on this, but still...  for the price of this adaptor and the contax 80/2 you could get a sigma 50mm/art and get the same look and obliterate the resolution.

     

    If metabones made a 0.55x unit for 6x6 lenses with 80mm+ image circles with sb ultra performance and apo correction for the hassy F lenses on digital sensors then we'd be cooking!  the 50mm/2.8 would result in a 28mm/1.6 with great mtf.  the blad 50mm at 2.8 on full frame almost matches the c/y 50/1.4 at f2.8 when compared for resolution on a7rii.  compressing the resolution by almost twice would be amazing in resolution terms. 

  15. This is exciting.  I highly doubt this unit will have optics of quality good enough to make investment in decent medium format glass worthwhile.  ie, even my Hasselblad 40mm/4, 50mm/2.8, 80mm/2.8 110mm/2 and 150mm/2.8 and this adaptor will only result in a set of lenses equating to:- 28/2.8, 35/2, 56/2, 77/1.4, 105/2.  

     

    This will be a formidable set no doubt, but at around £3000 for the hassy lenses (at current ebay prices) and probably £500 for the adaptor, as well as each of the hassy lenses being upwards of 1kg each! the excitement is damped since for £3500 you can get an incredible set of 35mm format lenses that will likely match the look, with moderately better image quality.

     

    Now, if metabones are watching and create something like this but with optics at the level of the SB ultra, then the hassle will be worth it (for resolution).  Unfortunately there aint enough fast (f2.8 or faster) medium format lenses like the shutterless hasselblad lenses to make the act of developing a truly superb focal reducer worthwhile in marketing terms.

    That said, I'll definitely be getting one of these.  my hassy's will deliver pretty good resolution and squeezing the lp/mm tighter with this (providing optical performance is good) will make the 110/2 a badboy!   

  16. Well I think the footage looked superb.  Each shot was clearly thought out to show the cameras capabilities.  Surely the idea is to show the camera in its best light.  This ain't a toy, its a c-camera/drone camera for professionals who want to see what the camera will do when lit/shot and processed to the best it can be.  If the camera was m4/3 mount allowing use of a speed booster, as well as having the need and budget for such a camera I'd be ordering one straight away.  

    well done to RED for getting this at the price point it is!  

  17. if shooting raw, you can use the lens correction on adobe raw before transcoding. you'll need to work out the distortion of the kowa for each taking lens focal length.

     

    expect around 15-20% distortion at the edges when using the kowa (or most 2x anamorphs) with its widest taking lens. 

  18. They'll stick their crappy F mount on there and kill any chance of the camera being popular with lens heads.  I love to think they'd make a mount with an ffd of 20mm or less and then sell f-mount adaptors to those who want to use nikon glass with electronic contacts.  the short mount would allow metabones to manufacture a suitable speed booster as well as adaptors for almost every lens ever made.  M4/3 and e-mount are where it's at.  Sony even do a e-mount to a-mount adaptor.  copy that and you;re onto a winner.

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