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richg101

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Posts posted by richg101

  1. 8 minutes ago, Dennis L Sorensen said:

    Thank you! We see all these mathematical equivalent photos from different size sensors and some don't believe in it because they say they can see a difference.. OF CAUSE there is a diffence. The lens designs are proprobly not the same.

    When comparing stuff like this, you need exact copies of all the involved things.. sensor, lens, subject.. Only the size can change. But this is not possible in real world, as there are many small differences.

    It's like most MF sensores are CCD. It's a completely different design, so you can't compare the image 1:1.

    But yes. I think lens design is what causes most of these highly controversial statements..

     

    Sorry but have you even taken the time to look at the lens designs (they are easily googlable)? They could EASILY have made the Sony GM 24-70 f/2.8 smaller with an older design. They chose to do a completely new design that can take a much higher megapixel count then the Canon can - (that was not a "With Canon you can" joke).. The Sony GM is superior - well atleast in sharpness that is! :-)

    I love shooting mirrorless. I can have a small camera to go on family trips, or I can have much DSLR-like lenses for work :-) With a DSLR it will always be bigger, even with pancake lenses :-)

    Mirrorless design vs mirror design.png

    If you read my post I said 'I have a feeling'.  my feeling was wrong. Fair enough.  well there you have it.  sony could have made a smaller lens with performance to match the shite canon offering, but instead used that extra space for further elements.  the result? a lens that delivers resolution good enough for the 42mpx a7rii.  

  2. 17 hours ago, John Matthews said:

    I just hope it doesn't run into this type of situation. Three FF cameras to scale: notice the mirrorless one has an enormous flange. I think it's just physics.

    a7RIIvs5DsRvsa99_24-70mmf2.8-800x353.jpg

    Petapixel had a whole article on this here:

    http://petapixel.com/2016/04/04/sonys-full-frame-pro-mirrorless-fatal-mistake/

    I have a feeling the reason the sony is so large is that it might be a re-purposed lens.  probably originally designed for a-mount, or at the very least designed to be onfigured to be used with a a-mount camera, and then the optical design has been translated into e-mount.  the additional 30mm length to make up for the lack of mirror.  

    2 hours ago, Nikkor said:

    I think Sony lenses are gigantic for two reasons. Firstly lens designers have mainly been working with retrofocus designes for the last 60 years. Look at the otus line, even the 85mm is some sort of retrofocus design, it permits even illumination and resolution across the image, at the cost of complicated and large designs.

    Obviously there is leica and the rest of rangefinder stuff, but here comes the second problem, digital sensors still need telecentricity, so this leaves us with large lenses for the time being. But this will change once the mirror becomes a thing of the past (unless the focal reducer approach is so good that it becomes the norm and this needs long register distances.

    yep.  micro lenses, cover glass etc.  all make shorter back focus distances a potential problem.  The Loxia lenses take leica style designs and apply correction for micro lenses and cover glass.

  3. 28 minutes ago, John Matthews said:

    The body looks nice, but don't people think it's a bit silly to carry a bunch of lenses, each with a huge medium format flange? I don't think they're getting around the physics. Same thing happened to the Sony A7 series cameras. Upon adding a G-master lens, it's the same size as its DSLR counterpart... the only difference is that the DSLR user will only have ONE integrated flange on the body to carry around.

    a 80mm/2 designed for what looks like the sony 50mp cmos would be small and lightweight - no heavier than a 50mm/1.4 for full frame.  The lack of mirror means the system benefits in the same way a leica M system benefits - small lenses due to not needing to be placed 45-75mm from the sensor to clear the mirror.  think scaled up Loxia lenses.  fast, compact, very high quality.  

  4. 11 hours ago, jcs said:

    However, it doesn't seem likely as if there was some 'magic', there would be a huge market opportunity for a MF to FF SB and that hasn't happened (especially as richg101 pointed out the low ISO limits of MF sensors). Real world examples using 'equivalence' again would be helpful to figure out either way what, if anything interesting (and real) is happening.

    A MF to FF speed booster is not a viable product because of a few problems:-

    1. a good quality optic will be very expensive.  the Kipon unit won;t perform as well as the speed booster ultra, and as shown on my tests a few pages up, even the speed booster ultra negatively affects the overall image quality when compared to a straight lens on full frame.  add to that the need for electronic contacts to use lenses like the contax645 or rolleiflex hy6 'digital ready' lenses.  the cost will mean the customer base will be limited.

    2. Most speed booster purchasers do so to get around having to pay for a full frame camera.  Therefore they'll also be less likely to invest the huge amounts in MF glass that (assuming a focal reducer were optically clear) will actually be worth focal reducing.  a 110mm/2 hasselblad, a schneider 180mm/2.8, a schneider 80/2, contax 80/2.

    3. because the likelihood of the focal reducer being of good enough standard (ie, better than a sb ultra) being almost impossible, and the likelihood that hardly anyone will be able to acquire a desirable fast mf lens, the likelihood that an end result will exceed a fast full frame lens, let alone meet that of what is possible on medium format is slim.  

     

    All said and done, I'll be buying a kipon mf to ff focal reducer, but in no way do I expect it to deliver the same quality I get from the same lens on MF.

     

     

  5. 2 hours ago, Brian Caldwell said:

    there is no magic to be found here.

     

    the magic comes from the available optics for a given format.

     

    1. you cannot buy a 60mm/1.4 aps-c lens equivalent to an old leica summicron 90/2 when used on full frame.  yes you can stick a 0.7x focal reducer on there, and I have done so (with the sb ultra on a a7rii).  the amount of defocus is the same but the rolloff is quicker on the focal reduced lens on aps-c.  the in focus areas are also drastically inferior, and there is significant reduction in fov, and added distortion.  all of these attributes contribute to the advantage of the larger sensor.

    2. you cannot buy a 50mm/1.4 lens for full frame that is equivalent to an 80mm/2 when used on medium format wide open.  close down 1 stop respectively and the real world advantage of medium format becomes even more pronounced.  

     

    I really wish there was a full frame lens system capable of acheiving the same look from my mf camera since i'd no longer be limited to running 80iso.  at the moment the limitation of slower lenses and 80iso means i am confined to flash work or daylight shooting.  until yourself or someone else designs and manufactures a viable alternative for smaller sensors the professionals will continue to buy into the phase one system for remortgage worthy money!  

     

  6. 1 hour ago, UHDjohn said:

    The reason why MF digital is 'better' has nothing to do with DOF or out of focus rendering and everything to do with CMOS vs CCD and the strength of the CFA's over the sensors. SONYCANONIKON etc put in the weakest CFA they can 'get away with' to maximise high ISO performance. MF digi back makers put in the CFA's which create the best colour fidelity and are not too bothered if this limits the high ISO ability. CCD vs COMS  - again CCD can't give you high ISO sensitivity but when it comes to reproducing 'sophisticated' colour it's a different animal.

    I agree with this to a point.  my 9year old leaf aptus ii 10 at 80iso (56mpx ccd, 16 bit) destroys my sony a7rii for colour in situations where there is good light.  Still I think you are wrong to disregard the effects of a large sensor on dof rolloff.  the new Phase 100mpx back is a sony cmos sensor.  being 16bit and developed to mimmic the desired look you get from a ccd in its comfort zone has created the best mf sensor ever apparently.  in good light I expect my ccd will deliver just as beautiful images, but in bad light the phase 100mpx cmos makes me wanna cry at how good it performs.

  7. you need to burnish the casing back to gloss with a very fine polishing pad.  i think a 4000 abralon pad will work well on this.  leave the taking lens on for protection of the rear element and to use as a handle to hold onto, then rotate the iscorama in the abralon pad.  make the abralon pad moist but ring it out so it's almost totally dry - just damp.

    a good quality black marker pen like a sharpie will darken the grooves on the grip.  

     

    3 hours ago, Bold said:

    Turtle Wax maybe?

    I'd avoid wax based products since these are nearly impossible to remove from glass if they end up on the elements.  i would however maybe look at t-cut or even brasso as an option.  as long as the cloth is almost totally dry and you quickly rub the casing uniformly the abrasiveness of t-cut may be the answer.   try the locking buttons first to test the processes.  then you don;t run the risk of ruining the main casing.

    ps.  the parts that are still black are infact anodised aluminium so mask them off so you don;t polish away the blacking of the metal!

  8. 13 hours ago, jcs said:

    I think we all agree with that point- what we can do in the real world with available equipment is all the really matters vs. math and theory. If there was a business reason to use a Phase One, I'd use one. Their cameras systems are top notch (design, usability, and final image quality). Currently the 5D3 and 1DX II with fast lenses (especially the 85mm 1.2L and 135mm F2L) can create crazy shallow DOF (sometimes too shallow to be usable wide open).

    Here's a test many don't realize they can try with any camera to better understand equivalence. Shoot with the same lens, change settings, then crop in post (images 3 and 4 from: http://brightland.com/w/the-full-frame-look-is-a-myth-heres-how-to-prove-it-for-yourself/ )

    Full Frame

    A7S_FF_105mmF4.5_ISO_2000.jpg

    Super 35 (cropped in post- same lens)

    A7S_APS-C_70mmF2.8_ISO_800_PostCrop.jpg

    Is there a difference? Sure, but so minor that the average person (client etc.) won't ever notice the difference. You can do this test with your MF camera, and crop to FF! Since you are using the exact same lens, only changing camera settings and cropping in post, lens and sensor technology will be identical. The only thing changing is effective sensor size. Try it! :)

    Thus unless a client could clearly see the difference, why would a business invest in MF bodies and lenses? At the ultra high end, it's more marketing/appearances, and perhaps most importantly, Phase One for example does produce the highest megapixel professional/studio cameras(?) along with what looks like the best processing currently available. As noted in the link posted in this thread, the 50Mpixel 5DSR is very similar in quality to the 50Mpixel Phase One for ultimate image quality.

     

    point of focus is the text on the front of the lens.  bokeh bubbles are the same for both shots meaning the ratio between the in focus and fully out of focus areas is the same.  HOWEVER, on the aps-c shot the canon text on the camera body, the underside of the tripod head, and the text on the flash are are more blurred than the full frame image.  

    so for a bigger sensor the dof rolloff is slower and therefore more of the camera is in focus.  as distance increases and focal length is lengthened this attribute is magnified.

     

  9. 13 hours ago, Andrew Reid said:

    Instead of reputation points, I am replacing the forum system with e-penis points from now on.

    i'm gonna have to start working hard to get some points.  anything to make up for my 1.5" fully extended.

    6 hours ago, John Matthews said:

    OMG this discussion seems pointless. FF vs. MF vs. phone vs. etc. That's not what this post was about. Let's move on... next.

    Guess what...

    "You can't convince someone against their will." Someone's grandmother once said that.

    this opinion is one of the main reasons certain very good photographers miss out on the better work - the disregarding of how important equipment really is from separating two equally good photographers.  naturally the one who decides to go that little further - investing in equipment you need to pay a lease to use, rather than saying to themselves they can spend the extra money on a holiday or a new car and carry on using run of the mill canon crap.  shooting medium format digital separates the men from the boys in the same way shooting Alexa and cooke s4 differenciates from someone shooting c300ii and eos lenses.  they're not that far off, but the people with the ability to differentiate see the difference and value the difference.  If it wasn;t there, phase one and arri wouldn;t be servicing the upper end of the market.  

  10. 3 minutes ago, Nikkor said:

    Your comparison only shows that speedboosters aren't perfect, but they preserve the larger format quality of dof (the size of the blur doesn't change in size, except for some "field curvature?")

    yes, this is true.  but a speed booster is a focal reducer.  the ultra is a marvelous piece of glass and as a rule a basic 50mm f2 + speed booster ultra (creating a 35mm/1.4) will vastly outperform most true 35mm/1.4's.  Technically a sigma 35/1.4 will meet or exceed, but at the cost of losing all sense of soul and character.   

     

  11. Full frame https://c2.staticflickr.com/8/7697/27662722381_982d10fc99_o.jpg

    APS-C + SB Ultra https://c2.staticflickr.com/8/7272/27737331565_423e3503be_o.jpg

     

    now I'm gonna say that in order to view the differences you should download the full size files, and bring them into photoshop so you can flip from one layer to another.  the differences wont be apparent without.

     

    The main thing is overall image quality.  shorter focal lengths just don;t deliver the same refined in focus areas - the point of focus on the aps-c shot is drastically harmed by the purple fringing.  Since the in focus area is less refined than the ratio between the in focus areas and the defocused area is greater- providing a greater level of 3d pop.  . but look at the defocus.  background looks about the same level of blur, but the blur level on the lens cap (circled) shows that the rolloff is different.  it's slight, but the difference is there.  this difference in rolloff is as far as I am aware dictated by circle of confusion of the different formats.  Lets assume we replaced the lens in shot with a human face, more of the face will be in focus with the full frame sensor area - due to the rolloff.  from the tip of the nose to the ears, the overall perceived rendering will show the entire overall face to be more in focus than with a wider lens.    the overall background blur will be the same, but the distances close to the point of focus will have a deeper useable dof.

     

     The point I'm making is that physics and available lenses give larger sensors the edge.

  12. 18 minutes ago, jcs said:

    Cool photo; the DOF looks odd- starts abruptly then looks like Gaussian blur vs. typical bokeh. Looks like something I could create on my iPhone along with Snapseed.

    DOF does look odd.  As a general rule we're not used to seeing relatively wide shots from a distance that provide such shallow dof, and refined in focus areas. view in full size and you;ll see the point of focus was the text on the boat.  makes the front of the boat jump out.  I'm happy to send the mos file from the camera if you want proof that no added blur was applied!    every person who sees this image asks what lens was used.  I always feel bad trying to explain that no matter how much they spend on a lens for a full frame dslr they'll never be able to replicate the dof rolloff and fov.

  13. 21 minutes ago, jcs said:

    I took the Full Frame Look (vs. S35) challenge and created images that were equivalent: http://brightland.com/w/the-full-frame-look-is-a-myth-heres-how-to-prove-it-for-yourself/ . Some folks posted 'debunking' shots with MF vs. FF but didn't use equivalent camera settings per the math (and not even the same framing).

     

    give me a shout when you find a lens/sensor that will replicate my leaf afi-ii 10 and a 180mm/2.8

     

    https://c2.staticflickr.com/8/7506/26997678725_133cd94b63_o.jpg

  14. 10 hours ago, Brian Caldwell said:

    Two afocal attachments in series should have significantly better image quality than a single shorter one with the same total squeeze ratio.

    definitely.

     

    On a side note the stacking of two off the shelf 2x units presents quite a few limitations.  length of units dictate longer taking lenses or smaller sensors in order to keep field angles small enough to avoid mechanical vignette.  both of which have and adverse effect on dof - meaning the effects from the system don;t show up as much.  also the longer focal lengths require larger diameter glass to provide adequate transmission of light.  I expect a 135mm on full frame, in combination with two 2x anamorphics will result in no faster than f5.6 apertures - even with the taking lens set to f2.8, the size of the anamorphs are gonna limit things.  I think for the ultimate setup based on this concept using off the shelf parts you;d want a kowa b+h and a 120-135mm at f4 on full frame, then a iscorama 54 on the front.  that way dof, fov, transmission, iq, and used sensor real estate are all optimmally balanced.  

    What will be rather mad is when something like a big rare Kowa 35 - 2x is partnered with a 75-85mm/f2 on a portrait orientated a7s, then OLIVIA SCOPE is installed up front.   16:9 aspect, with lots of oval defocus, incredible shallow dof, wide angles, efficient transmission and deadly sharp.

     

  15. The fact that you are regularly using the usb port on the camera to charge a battery would imo go some way towards explaining why you;re having issues.  basic logic tells me to avoid using a delicate connection like a micro usb port for everything except firmware update.  it's NOT a professional port.  When using a Sony camera for professional use you have to consider which functions are genuinely right for pro use.

    canon use common sense and don;t provide in body charging for the exact reason that if they do, people will use it and knacker their usb port.  Since the A7Rii sits within the consumer devision sony have included consumer functionality - just because it's there, if you;re using a camera professionally it should be basic logic that tells you to invest in a £20 external charger, and a proper card reader.  

     

    I'm unable to comment on your other problems, but based on the fact that you;re using the usb port for a job that should be done with dedicated devices like chargers and card readers, I assume other logical steps to ensure a consumer device is kept within it's comfort zone may be being overlooked.  

  16. fantastic idea.  though I'd suggest starting with a small high quality 2x, then install a 1.5x iscorama on the front.  The problem is that since your taking lens now needs to be longer, the front element is also going to be a lot bigger.  a 150mm f2.8 lens for full frame has a front element way larger than a 85mm/2.  I expect a rather good combo would be a kowa b+h and a isco54.  on full frame you'll need around a 135mm in order to keep field angles low enough  on aps-c an 85mm will be a good match.  

    it's funny, I was actually talking to someone a few days ago about using a sensor in portrait and an anamorphic in order for shooting fast moving subjects with less rs issues

      

  17. It appears that it's only the action sports/skater guys who still use canon dslr's for movie making..  they're so busy enjoying their full throttle lives they don;t have the time to sit browsing the web for the latest and greatest gear.  The only other camera the action guys seem to know about is gopro and if they're happy with the ghastly image from that, a crippled 5dmk4 will be a dream.  If canon didn't reach out to this crowd then they'd not sell any dslr's for video stuff

  18. 1 minute ago, omar said:

    Great article! Wish these prices were this low before I bought my sony F35. F35 is amazing but having 4K raw as an option is definitely an advantage. Thanks for sharing your experience Andrew!

    I don't know..  The image from your f35 will always be special, not to mention the motion.  I'd take fullhd upscaled to 4k from an f35 over any camera below an alexa.  what lenses are you using predominantly?

  19. That review really shows how the lack of c-log impacts on the 1dxii being usable to produce images good enough for todays demands.  that blown window for example, would be blown on a 1dc, but the rolloff would be drastically more filmic.  i tell you what..  that tokina 11-16 doesn;t half produce vile images!  - i don;t think that helped the piece.  You can see he needed a wide, and because the camera doesnt give good results in full frame mode, the stellar wides available in the L series are no longer wides due to needing to go for a sensor crop.  for a film about craft, a handycam feel to the highlight rolloff isn;t good enough IMO.  

  20. imo the xdcam 35mbs files from the f3 are more 'solid' than the higher mbs xavc-s from the a7s.  colour and motion feel right from the f3 too.  s-log was perfectly implemented within the pmw f3, f35 and f65.  usable dr is more on the f3 from what I've seen too.  Love my F3.

  21. older summicrons..  35 (snooted front), 50 (snooted front) and 90.  for s35 i don;t think there are a better matched set.  serials starting before 28xxxxxxxx tend to have coatings that work well with the single coatings of the isco.

  22. 8 hours ago, kidzrevil said:

    @richg101 have you tried the a7sii ? How is it in comparison to the a7rii

    IMO it's dependent on whether you;re willing to invest in a speed booster ultra for the a7rii.  if you can handle the extra $500, the a7rii wins for both video and stills unless you;re shooting 6400iso and higher all the time..

    12mpx isn;t quite enough for still photography IMO.  it's ok for shallow dof stuff, but when you want a wide shot with everything in focus I find the 42mpx makes for way more pleasing images - particularly landscapes.  I had an a7sii temporarily and decided the low light advantage and s-log3 wasn;t worth getting rid of the a7rii.  I'm a still photography hobbyist who earns money from selling tifs for prints, and sometimes do wedding stuff, product photography etc.  and for this the a7rii is king.  the fact that the s35mm mode on the a7rii is one of the best internal 4k recording images available is a bonus for when I need to shoot video for the day job

     

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