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Jerome Chiu

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Posts posted by Jerome Chiu

  1. 2 hours ago, noone said:

    Just pointing out that you are using a few examples that get you close to getting AS shallow DOF with it than is readily available FF but those are few and far between and do not get you SHALLOWER than what you can get for the most part. 

    Other things being equal, 28mm f1.4 on GFX has shallower DoF than 24mm f1.4 on FF; likewise 105mm f1.4 on GFX has shallower DoF than 85mm f1.2 on FF. It's physics.

    As for "few and far between": how about Sigma Art 20mm f1.4 (on GFX 100 4K UHD 0.92x crop, wide open at mid- to close distance or stopped down at infinity), Sigma Art 24mm f1.4 (ditto), Sigma Art 40mm f1.4, Canon EF 40mm f2.8 STM, Sigma Art 50mm f1.4, Leica Summilux-M 50mm f1.4 ASPH, and pretty much every FF lens with focal lengths equal to or longer than 75mm?

    Of course, many people don't want to deal with the soft vignettes that often result from putting full-frame lenses on a larger format such as the GFX. I totally understand that. Personally I don't mind, and I would stick with lenses that completely cover the sensor in those cases where vignetting is not welcome. This is also where the Hasselblads come in, too.


    2 hours ago, noone said:

    There are many valid reasons to get the GFX and I think the OP SHOULD get it over the Canon from what he has said but given existing lenses that are available, shallow DOF still usually goes to FF over the GFX for now anyway for the most part.      If you just use slow lenses on either, then yes, the GFX DOF control is "better" (my opinion).       300 2.8 is a sweet spot for FF for me too since I use it sometimes for live bands outdoors at night or low light gigs with room and I need the high ISO I get with my FF camera. 


    For the record, I don't go after DoF this shallow. What I'm after is nice bokeh at f4 or f5.6 from 28mm (FF equivalent) upwards. If I need shallower DoF at all, then it would be with lenses wider than 28mm (FF equivalent), e.g. 20mm f2.8, 14mm f2, etc.

    As we all know, we often need more, not less, DoF, thus we appreciate the smallness of M43 and 1-inch sensors under those circumstances.

    One extreme example (albeit in photography) is when one tries to hit focus with the Cooke Portrait PS945 (229mm f4.5) using 8x10 film (quite adventurous, for it is supposed to be a 4x5 lens, but it does cover 8x10 at portrait distance wide open), yielding a 32mm equivalent (to FF) angle of view -- very good for environmental portraiture. But the lens's famous soft focus effects diminish as we stop down, so if one covets the soft focus effects then he has to struggle with this extremely shallow DoF while trying to nail focus looking at the ground glass with the image upside down and left-side right, where even the brightest ground glass is much darker than the EVF we are now used to. We are talking about a rough equivalence of a 32mm f0.63 lens here.

    I am telling you all these since you love shallow DoF, my friend. Cheers!

  2. 30 minutes ago, thebrothersthre3 said:

    Does a full frame like the Nikon Z6 with a speedbooster get the same FOV as a Fuji GFX

    First and foremost: you could forget about AF, as of now, if you do it. Currently, I could think of 2 ways to do it: (a) EF to E Speedbooster, then E to Z adapter (yup, the notorious Techart, my friend!); (b) Kipon Baveyes EF to E, then (again) E to Z.

    Onto your question: yes, and a bit more as well. A one-stop focal reducer introduces a 0.71x crop factor, so we get a 0.71x crop for stills, a 0.76x crop for 4K DCI full-width, and a 0.8x crop for 4K UHD. In other words, we get roughly the same crop factor for 4K UHD with the focal reducer in FF as the GFX for stills.

    Only as a rule of thumb: a full-frame lens 75mm or above should cover this crop, but of course we should conduct tests to verify it before jumping right in.

  3. On 2/3/2020 at 6:44 AM, noone said:


    My kit of (mostly) ancient lenses includes a 24 1.4, an 85 1.2 and 300 2.8 and I used to have a couple of 50 1.2 (oh and I have a 135mm 1.8 even if it is not very good) lenses used FF ....what would I use to replace those with the GFX that had shallower DOF?

    No question that it should work if there were the lenses available but there are not.     I would also love to try my Canon 17mm f4 L TS-E on a GFX as it would fit without vignetting and be wider.

    24mm f1.4 on FF gets an approximately 26mm angle of view with the 4K DCI full-width crop, and about 27mm with the 4K UHD crop. I'd recommended the Sigma Art 28mm f1.4 for use with the GFX 100 for a roughly equivalent angle of view, viz. 0.92x28= 26mm. Yes, it does cover the 0.92x 4K UHD crop inside the current GFX 100.

    As for the 85mm f1.2: about 91mm (4K DCI full-width) and 96mm (4K UHD) respectively. Both Nikon and Sigma have, each of them, a 105mm f1.4. It would yield a 96mm angle of view (FF equivalent) image in the 4K UHD crop on the GFX 100.

    You could put the 300mm f2.8 onto the GFX to see if you like it. If you need the FF equivalent of 300mm, then probably you should stick with smaller formats, as is the case for everything tele.

    The TS-E 17mm covers 54x40mm sensors (but with next to no movement), so of course it covers 44x33mm, with room for some movement. The same is true for the TS-E 24mm Mark 2. I'd guess the newer ones (viz. 50mm macro, 90mm macro, 135mm macro) would all cover with room for movement.

  4. 8192x5462 yields 44, 744, 704 pixels, i.e. very close to the rumoured 45mp of the R5. If so, then that means a 2.13x crop for 4K DCI, pixel-to-pixel. If I have to guess, I'd go for it having a very short burst for 4K 120P, like 2 seconds.

    I'm more interested to learn whether it does 2K 240P, even if it'd likely yield a crop up to 4.26x for it with a burst of 1 second. Chance to put S16 lenses to good use! 

  5. 2 hours ago, noone said:

    Only if all things are equal and they are not as there are not as many fast lenses for MF than there are for FF.       There are actually some MF lenses (mainly for aerial photography) that are just silly fast but are very rare and very expensive while more "regular" lenses favour FF for speed at the moment.     The fastest lens for the GFX is what, 110 f2?   So about a 87mm 1.2 equivalent?    There are a few f1 lenses for FF as well as 1.2 and lots of 1.4.    

    Don't forget we already have the Metabones Hasselblad V to GFX Speedbooster, with which we get 0.56x crop for stills, 0.62x crop for 4K DCI, and 0.65x crop for 4K UHD.

    The Hasselblad 110mm f2 would thus get the equivalent (to full-frame) angle of view of 62mm, 68mm, and 72mm respectively, and one stop faster (i.e. about T1.6). The image characteristics of this lens attached to the GFX are thus very roughly equivalent to 62mm f1.1, 68mm f1.25, and 72mm f1.3 (in full-frame) respectively. You could do your own calculations for other Hasselblad V lenses.

    The shutterless F and FE lenses could be easily de-clicked, and all have long focus throw (around 300 degrees!).  One downside is they don't use rounded aperture blades, and some use as few as 5 (FIVE!), facilitating some rather unique highlight bokeh pentagons.

  6. 3 hours ago, Alt Shoo said:

    [Snip] However my concerns are with the lens choices. I am aware of the limited options, but aren’t there converters which will allow me to use other lenses? Also regarding those converted lenses, there may be some vignette-ing? Even if using full frame lenses? And it does 10 bit 422 external.

    I don’t look at them as opposites, more like parallels. 

    Everything that Andrew has said in reply to you, plus:


    1. Metabones Hasselblad V to GFX Speedbooster. It brings real medium format to digital! Good choices (for stills as well as video) are

    (a) 50mm f/2.8 F (forget about the FE versions -- the electronics won't communicate, and they are more expensive)

    (b) 80mm f2.8 F (the CF or C versions are also good, and optically the same; but the F version focuses closer, and could be easily de-clicked)

    (c) 150mm f2.8 F

    All three above are excellent optically, could be easily de-clicked, and surprisingly affordable. I have omitted the legendary 110mm f2 not because it isn't good (it is), but second-hand price is very expensive.


    2. For video use, the 16:9 4K crop of GFX 100 is 0.918x, i.e. only a little larger than the 0.934x crop of Red 8K VV at FF. Any FF lens, except perhaps the widest of superwides, should cover. The DCI 4K crop is just a bit bigger, but we still have room to experiment. Judging from screenshots I've seen (I've forgotten where....), Sigma 24mm f1.4 Art should most likely cover the 0.918x crop wide open at near- to mid-distance, or stopped down at infinity.

  7. On 1/13/2020 at 8:47 AM, Cinegain said:

    lol @Andrew Reid 'slower apertures'. You did that on purpose, didn't ya? ?

    Joke's on you. I can not stand the use of 'fast aperture'. 'Slow aperture' doesn't bother me. ?

    Now this is interesting. Mike Johnston, as Chief Editor of Photo Techniques, commissioned a series of three articles on bokeh back in the 1990s, and he added an "h" to "boke" (Japanese "boke-aji", lit. "quality of the blur") so people wouldn't pronounce it as rhyming with "broke". It has caught on -- I mean, the spelling with the "h" -- in the English language enormously, while the Japanese have moved on, nowadays, to a different term, viz. "outto fokasu". Go figure.

    He could also be credited for anointing Leica's 4th generation 35mm Summicron (last generation pre-asph, designed by Walter Mandler) the "Queen of bokeh" for rating it 10 out of 10 (one of three lenses that get this rating) for its bokeh rendering. What many people fail to realize is that Johnston specifically refers to the bokeh rendering of this lens at f/5.6, not at f/2 where people are baffled why the rendering is very far from 10 out of 10.

    So yes, we should be talking about the rendering of the bokeh at different apertures, and especially while stopped down to f/4 or f/5.6. It is wrong to assume that bokeh is only about blurred background in the widest apertures.

    [Edit] Here is a recent article of his, where he revisits this ongoing tale. Also note that his latest article is, rather coincidentally, also on bokeh.


  8. Some calculations.

    A "pixel-to-pixel" 3840x2160 crop from 3882x2912 yields a 0.87x crop factor. Good news for owners of native G lens; much less so for owners of full frame lenses. But I guess most FF lenses except super-wides should cover it in practice, i.e. wide open at portrait distance or stopped down at infinity.

    For those looking for the MF look: 0.87x0.71 roughly yields a 0.62x crop factor, i.e. 6x6 and 645 lenses with one-stop speedboosters should all have image circles big enough to cover it.

    The Cooke Anamorphic/i Full Frame Plus Series has the following focal lengths (all in mm): 32, 40, 50, 75, 100, 135, 180. Putting them on the anticipated new "GFX 100 H" would yield the equivalent angles-of-view of 16, 21, 25, 38, 51, 68, 91 (all in mm) lenses. Someone would surely do an image circle test soon after this open gate anamorphic mode has become a reality. My guess is that the four at the tele end (75, 100, 135, 180) should comfortably cover.


  9. 8 hours ago, Nikkor said:

    This plus https://www.metabones.com/article/of/HasselbladVtoFujiGmountSpeedBooster 70mm look. Anyone wants to buy a kidney?



    This is exciting.

    0.79x0.71 gives us roughly a 0.56x crop , very close to the entire image circle of a 6x6 lens.

    The 16x9 crop of this sensor is around 0.92x (on the current GFX 100 - a 16x9 rectangle cropped from open gate would yield a slightly larger crop ), i.e. most FF lenses should be able to cover it. A 645 lens with a speedbooster (0.92x0.71 => roughly 0.65) would cover it, too.

  10. 5 minutes ago, seanzzxx said:

    Because they should've had a better feeling for their market, you mean?  [snip]

    Exactly; and it isn't only Cinema5D over Andrew Reid, it's also Cinema5D over Philip Bloom (who lives in London, AFAIK). We've known for ages that subscriber count doesn't count, nor does view count; what counts is the number of buyer decisions positively influenced by practitioners like Andrew Reid and Philip Bloom, who both have large and trusting followings. Both speak their minds, but that hasn't stopped, e.g., Kinefinity from asking Bloom to test their new cameras, and this has been key to Kinefinity's becoming a presence in this very competitive market.

  11. 9 minutes ago, seanzzxx said:

    Blackmagic HAVE their own excellent forums (at blackmagicdesign.com), and their employees actively comment on different forums.

    That makes their choice of those who were given early access of their new cameras more, not less, mystifying, right?

  12. BMD is a manufacturer of niche products, and as such must be able to locate where a large bulk of potential (and actual) customers are; so Andrew has a point here, viz. BMD has totally missed a golden opportunity to connect with a large number of potential buyers.

    They should take a leaf out of other niche players in the industry: Red has its own forum, and forum members could seek out some senior members who have early access to new models for comments and guidance; by a similar token, PhaseOne has a good and reliable presence in getdpi.

    I'm also quite amused at Andrew's reference to Cinema5D. I first came across them when I was going through coverages of trade shows, and their Youtube coverages have been the most cringe-worthy of all, by a country mile. I have come to skip them almost all the time and only watch them if they are the only channel that covers a certain product; this has happened a few times to my annoyance.

    Yet I agree with most fellow members here that Andrew should not have published that rant. It doesn't do him much good; but it does enhance my trust in him enough that I've just registered as a forum member and composing my first post. YMMV.

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