Jump to content

ac6000cw

Members
  • Posts

    436
  • Joined

  • Last visited

Posts posted by ac6000cw

  1. 3 hours ago, kye said:

    I find that simple answers come when you understand a topic fully.  If your answers to simple questions aren't simple answers then you don't understand things well enough.

    I very much agree with that - the opposite of someone filling an answer with the latest buzzwords, fashion statements and acronyms to gloss over the fact that they don't really understand the subject.

    I've been interested in science and engineering from quite young (the first book I ever bought was about electricity and magnetism). Favourite subject at secondary school was physics, helped a lot by an enthusiastic teacher who really understood the subject and could explain the fundamentals behind it very well. When I went on to study physics and electronics at university, in marked contrast some of the lecturers were terrible at explaining things in a simple fashion.

    One lecturer in particular kept pushing his own textbook, which was just as impenetrable as his lectures, so some of us students just gave up and found a book that explained the basics of the subject much better, just to get us through the exam at the end of the year... (and it was a subject that in my subsequent electronic design engineering career I've become much more familiar with - so now I know it's mostly much less complicated than it seemed at the time).

    "Simplicity is the essence of good design" I've found to be very true. If things start getting too complicated and messy in a project, it's usually a sign that I didn't set off in the right direction at the 'blank sheet of paper' stage.

  2. 1 hour ago, kye said:

    It seems to have one of those boxes that controls the lens and provides a rocker switch for zooming etc, maybe that narrows it down?  Maybe it's an ENG lens rather than a cinema lens?

    If it was a real working 16mm film camera, I don't think it would be an ENG (Electronic News Gathering) lens, as they are designed for professional portable video cameras (which in the late 1970s would have been triple vacuum tube image sensor cameras using a dichroic colour splitting prism, thus having a long flange-to-sensor optical path).

    But of course in the movie it's basically a prop, so doesn't have to be a working camera.

  3. 3 hours ago, John Matthews said:

    You can tell a difference if you pixel-peep to 200-600% and A/B the images. I've also noticed a slight color shift too. There are also a few artefacts, but it's still 5.9k downsampled to 1080p 10 bit- not bad. If you slap on a touch of sharpening, no normal view could tell the difference and you have something that would be 5% the size of a 6k image.

    I did a similar 1080p to 4k comparison with 10-bit 50p HEVC files from my OM-1 very recently (as a check after I'd updated the FW to the latest 1.6 version). 1080p is nominally 40Mbps and 4k is 150Mbps.

    With the 1080p upscaled to 4k (using the FFMPEG zscale 'spline36' filter), at normal viewing distance on a 55" native 4k OLED TV I could tell them apart (as I know what to look for) but it's not easy. A normal viewer wouldn't notice. I've done the same comparisons in the past with files from my G9 with the same result.

    As a consequence of this, most often I record in 1080p 10-bit and save 75% of the storage space, unless there is a reason to want maximum resolution/quality e.g. it's an 'unrepeatable' major trip or event, to allow for re-framing or extraction of 4k stills. For the last one (which is handy for wildlife), I often record at 4k 24/25/30p 10-bit as that is sharper on the OM-1 than 4k 50/60p, but use 1/100 shutter speed to reduce motion blur while being reasonably usable as video footage as well.

  4. 1 hour ago, John Matthews said:

    I think the Intel Air i3 must have some sort of hardware for that though.

    AFAIK, the GPU in the 'Ice Lake' CPUs has hardware decoding for up to 10-bit 4:2:0 HEVC i.e. 'Main 10' profile, assuming you have a Retina MacBook Air - https://en.wikipedia.org/wiki/MacBook_Air_(Intel-based)#Retina_(2018–2020)

    Any higher HEVC profile e.g. 10-bit 4:2:2 has to use software decoding on those machines.

    1 hour ago, John Matthews said:

    It should also be noted that the video compares the full resolution 4k/6k to the 12mbps HEVC files and I'll be damed if I can tell the difference on my M1 iMac in full screen Youtube mode (4.5K). I've even played around with the 6mbps files and they didn't seem that degraded.

    Not surprised.

    I often upload stuff to YouTube as 4k 50p using HEVC at 15-30 Mbps (using 'constant quality factor' encoding). I used to use higher bitrates, but decided it wasn't worth the extra storage space/upload time. HEVC is generally a very efficient (quality versus bitrate) compression codec.

  5. 5 minutes ago, John Matthews said:

    I think there's a fine line between making stabilization appear natural.

    Definitely - it's why I like the way Olympus/OMDS IBIS operates on the OM-1 & E-M1 iii. When I use proDAD Mercalli for stabilisation in post I usually choose the 'Glide Cam' option, which gives a floatier feel with lower warping artefacts (and less cropping) than the default 'Universal Cam' setting.

  6. 15 hours ago, John Matthews said:

    My feeling is that H quality would be better than the lowest available bitrate in the camera (20mbps H.264 8bit) as it's 12mbps H.265 AND 10bit. I think the compression is about the same but with more color information. I haven't really tried the M quality- the compression seems massive in that though. It would probably depend on the scene. The quality of the H Proxy really looks quite acceptable. The L quality was a huge step down though. I'll need to try the M setting tomorrow.

    Thanks for the info.

    15 hours ago, John Matthews said:

    I have the Panasonic 70-300mm lens and it has great Dual IS 2. I haven't really noticed an improvement to already one of the most stable setups on the market. In face, I'd say the EOIS interferes with the OIS of the lens. Again, I need more testing.

    Robert May also commented in his video that it didn't seem to improve long telephoto stabilisation. Not that surprised as OIS in the lens can be as or more effective than IBIS and/or EIS at long focal lengths, at least for pitch and yaw.

    Now that the enhanced EIS is out in the wild, doubtless Panasonic will be getting lots of feedback, so there may be performance improvements to it in the future. For the vlogging situation, it sounds like it needs to be made a bit more 'floaty'.

  7. 5 hours ago, kye said:

    Panasonic actually has really nice colour - it's just not cool to say it out loud on the forums but I hear it from people in private quite often.

    I agree (having owned 10 of their hybrid cameras and 2 camcorders in the last 15 years).

    Panasonic has a long heritage in professional video (going back over 60 years) and it shows. I think the GH5 became a very popular camera for video because it was a good all-round, reliable, video tool in most situations, rather than excelling in any particular area at the expense of others or having a specific SOOC 'look'. 

    For a bit of fun, this is 9 year old, basically SOOC, FHD 50p video from a Panasonic LX7 'enthusiast compact' with a small 10MP 1/1.7" sensor. There's some obvious aliasing/jaggies and I think the reds/oranges in particular are exaggerated. But for a camera launched in 2012 that fitted in the palm of one hand and weighed 270g I think it is reasonably decent (and could be improved in post). SOOC video from a G6, GX85 or G80 would leave it in the dust though, having much less aliasing and better balanced colours.

     

  8. 18 hours ago, kye said:

    This is a fundamental split in the camera communities - those who like the look of cinema and those that like the look of video.

    For my own stuff, I prefer it to be as 'faithful as possible' to the original scene, within the limits of the tools I've got and the amount of time I'm prepared to spend fiddling with it. I don't care what someone else wants to categorise that as, but I suspect it would come under your 'video' category.

    Personally the parts of the production process I find most interesting are being out-and-about recording the content, the basic editing (the clip choice, 'flow' and the cutting) and getting the best out of the ambient sound. Adjusting the image doesn't usually get much more advanced for me than brightness, contrast, saturation and sharpness, unless there's a clip that's particularly 'off' what I think it should look like in the lighting conditions at the time.

    But I'm perfectly happy respecting and enjoying other peoples artistic choices, including abstract art (which is inherently non-realistic). But nobody likes every piece of art they view...

  9. 8 hours ago, John Matthews said:

    One "issue" I'm seeing with proxies is it caries the 4 channels of audio is you're shooting MOV and you choose the highest and medium quality proxy. That's probably the behavior you'd want, but I'd really like to have some sort of option. The only way to get 2 channels (L and R) in the proxy is to record in the MP4 option or you go to the 720p proxy (H.264).

    In terms of file size, proxies are often less than 10% of the "keeper" file- huge savings. Now, I need to figure out the best to use them in Final Cut Pro. I imagine you could put the bigger files on a much cheaper storage option and just edit with the proxies.

    Another cool thing is to apply the Realtime LUT to only proxies and leave the original as vanilla V-LOG, much like a RAW + JPEG photo workflow.

    I don't own the camera, but looking at the updated manual the 'H' proxy file HEVC bitrate looks quite reasonable at 16Mbps for 60p/50p and 12Mbps for 30p and below - roughly equivalent to the 8-bit FHD AVC mp4 bitrates of 28 and 20Mbps. It would be interesting to know how the quality of the 'H' proxies - when recording 'main' 4k - compares to 'main' FHD recordings at equivalent bitrates e.g. is it doing high quality down-sampling from the 4k stream for the proxies?

    image.png.4d819f980df921e2b864eba53a43f59a.png

    Another short YT review of the latest firmware (from someone who is primarily a wildlife photographer using a Z9, but also uses an S5iix primarily for video):

     

  10. 6 hours ago, mercer said:

    No offense to the photographer of that shot, but that looks like it could have been shot with any standard profile from a camcorder in auto mode.

    According to the EXIF data on Flickr, the still was taken with a Canon EOS 1100D (Rebel T3 in the US). I think it is a little over-saturated (the reds in particular), but is otherwise a reasonably colour accurate photo of 'Mayflower' in that time period. Here is another photo of it taken with a Canon EOS 40D by a different photographer - https://www.flickr.com/photos/125085162@N06/21175458306/

    There are a few colour stills on Flickr taken by Paul Cook at the same event with the 5D Mark III, which I think look nicer than the video (generally more vibrant, and with nicer skin tones) - https://www.flickr.com/photos/paulwilliamcook/albums/72157648396375737/

    But other than me not liking the colour grade (which is an artistic choice anyway) I agree the video looks good.

     

     

  11. 7 hours ago, mercer said:

    And I'd be remiss if I didn't post this video from a British filmmaker named Paul Cook. It was the video that made me buy my 5D3 and install ML Raw on it and never look back. After 7 years, I'm still chasing what he was able to capture in an afternoon...

     

    I really dislike the colour grade in that video - low-contrast and de-saturated with (to me) a grey-green cast. It sucks all the life out of the event it's recording... How do you judge the colour capability of the camera itself from that?

    (I know the heritage railway and the location it was filmed at quite well).

    Not my photo and a different location, but this is what the 'Mayflower' locomotive looked like in reality):

    8106439963_437dea7fa5_c.jpg

    From emdjt42 on Flickr )

  12. 47 minutes ago, kye said:

    One thing I do see, however, is that it's possible to have too much stabilisation if the camera is moving in 3D space, because if you stabilise too hard then you get that gimbal effect where the camera is locked onto a direction but is floating around in space like a drone trying to hover.  If the stabilisation isn't quite as good and leaves a little shake in the frame then the floating blends in with the shaking and it just looks like hand-holding and doesn't look so odd.

    For general video, I prefer a small amount of 'float' in the stabilisation - it looks more natural.

    For handheld or monopod long telephoto video, I need all the stability I can get, so it's Panasonic 'IS Boost' or Oly/OMDS '+1' level stabilisation in that situation for me.

  13. 2 minutes ago, eatstoomuchjam said:

    Heck, there are already dozens of videos just about the Pyxis talking about how it's the best camera released in years or the most ho-hum camera announcement so far this year.  Bonus: almost none of the people with those videos has even seen a Pyxis in person, much less actually shot with one.

    ...and if they had picked one up and shot with it, they might like or dislike it for reasons unrelated to the video it can produce (like where the buttons are, how the menus work, battery life, monitoring options etc.).

  14. 11 minutes ago, SRV1981 said:

    I just realized - I did come to the wrong forum. I just assumed this was a wider community than what actually is. Many view themselves as filmmakers. I do not, I’m sure there’s other forums/places to chat just about equipment etc and not ruffle weathers of those who see themselves as “filmmakers”. 

    Don't take forum discussions and comments quite so seriously - Kye discusses equipment too. I think this forum has always been biased towards that side of things. But the equipment is used as creative tools, so both it and the creativity are very much linked together. But if you're mainly interested in the equipment that's fine as far as I'm concerned - probably most of the threads on the forum are related to equipment and tools.

  15. 1 hour ago, kye said:

    Once you have enough DR to shoot the scenes you need to shoot, having more is actually a liability rather than a feature.

    I agree.

    1 hour ago, kye said:

    I definitely agree that one of the main challenges is taking a clip that was shot in LOG and has 10-14 stops of DR in it, and somehow stuffing that into Rec709 which has just over 5 stops of DR.  This obviously manifests in having to crush or severely compress various areas of the luminance range, but it also means that the source material can have colours that are dramatically more saturated than Rec709 can contain and you'll need to work out how to contain those too.

    I often apply an S shaped contrast curve, compressing the highs downwards and lows upwards and expanding the mid-range to increase contrast. Balancing the compression and expansion (and the inflection points) to get it look nice is the tricky part of course....

    And then there's the accuracy or otherwise of the Rec 2020 to Rec. 709 colour conversion - I think every HLG to Rec 709 conversion LUT I've tried has a different take on this...

  16. 1 hour ago, kye said:

    I co-produced a 5-min short with my sister a long time ago, and we estimated that all up it had 10,000 person-hours in it.

    Not at all surprised - doing that is far more complex and creative than the simple documentary stuff I normally produce.

  17. 9 hours ago, kye said:

    You might think that an hour sounds like a long time, but it's nothing compared to how long it will take you to edit something anyway.  Casey Neistat did his daily vlogs, which were usually between 5-10+ minutes each, and took 5-9 HOURS to edit.  This might sound like a lot, but he was an experienced editor even before he did his 800+ daily vlogs, and he also mostly knew what the film was about etc, so he wasn't filming without a plan.

    Based on my own experience of putting together 10-20 minute YT videos, I'd agree with that. I don't usually do the whole editing process in one go - more often it's broken into 1-2 hour sessions and from start to finish it spans a week or more.

    My usual process to create something for YT is:

    • Decide on the topic/subject for the movie (based on what content I've already got, usually from an event or place I've visited, recently or in the past).
    • Choose the clips that might be included.
    • Decide on a 'flow' for the movie - is it going to be basically chronological or geographical?
    • Put the clips that might fit into the flow into the editor media bin.
    • Put the clips onto the timeline in the right order. There might be 30 or more.
    • Do a very rough cut and play it. Delete or trim the clips to improve the flow and get the overall length within the target (it's almost always too long to start with). Repeat the cut & trim cycle until happy.
    • Go through the timeline and adjust brightness/contrast/saturation/colour as necessary (this can be very time consuming!). If a clip is proving really awkward to adjust, decide if it's essential to the flow. If not, could it be discarded or replaced with different one?
    • Do a similar adjustment process for the audio content (equally or more important as the picture content).
    • For the wobbly clips (which for old content will be quite a lot of them!) try to stabilise them - another time consuming activity!
    • Add titles to tell the viewer more about what they're looking at. This often involves some research to find the information.
    • Add timeline markers and generate a list of YouTube chapter points from them.
    • Render out the movie and play it through to review it. Fix the issues found (there will be some...).
    • Render it out again and upload it to YT as a 'private' video.
    • Add a description, the chapter list, a suitable thumbnail and the 'end screen' stuff in the YT 'Studio'.
    • Check it plays and looks OK on YT.
    • Make it 'public' on YT and hope al least a few people watch it for more than 10 seconds...

    The above also needs cups of coffee and maybe wine too 😉

    SRV1981 - next time you watch something on YT, just think about how much creative work and time has probably gone into it.

     

     

  18. 2 hours ago, Clark Nikolai said:

    Interesting. I've been working in REC709 for the sole reason is that I'm just not ready to jump in to REC2020 and the learning curve that it might have. I also might need a new monitor or something. At some point I'll learn all about it as it seems to have huge advantages over REC709 and I want to have them. (Another thing that I want to one day learn about is ACES, another big scary thing.)

    My D16 has a colour space that is like HLG called Bolex Wide Gamut. It keeps the full dynamic range of the image but isn't flat looking like Log would be so is watchable even before using a LUT or something. Here's a white paper about it.

    https://digitalbolex.com/wp-content/uploads/2016/05/Bolex_Log_Bolex_Gamut_TechSum.pdf

     

     

    Below is an approximate comparison of transfer curve for various Log and Sony's three versions of HLG.

    From the Bolex PDF above:

    image.png.91bc094fbfd25ddc255645991ee2ebb8.png

    The three versions of HLG that Sony cameras support (from https://xtremestuff.net/sony-and-hybrid-log-gamma-hlg/ ) - HLG3 (upper curve) is the closest to the Rec. 2100 standard :

    Sony-HLG.png?x31412

    A chart of various Log formats from https://www.dpreview.com/forums/post/64243940 (note the 3 EV spread in the high EV limit between the various curves). The highest DR curves look to be C-Log2, S-Log3 and V-Log - but of course they do that by being flatter in the important mid-range area i.e. fewer levels per EV, increasing the chance of banding if pushed too far in post. Note this chart is -10 to +10 EV vs. IRE 0 to 110%, the other two are -8 to +8 EV vs. 10-bit digital code values.

    62f1ebaa6a2141a2a5cee25751f8871c

  19. 37 minutes ago, SRV1981 said:

    Under very clear differences and Fuji and canon have a much more appealing image. That said I show the clips to family or friends and they always pick canon then Fuji 

    But how much of that is due to relatively small differences in brightness, contrast and saturation (all of which can be adjusted in post and usually in-camera by tweaking the picture profiles)?

    We are all used to colours changing due to natural lighting variation, and most people are drawn to bright, colourful, vibrant scenes - which is why the 'standard' profile on cameras is often relatively high in contrast and saturation to produce 'punchy' looking stills and video.

    When comparing cameras (if I'm thinking about buying one), I'm much more concerned about unnatural image distortions, like aliasing, moire (especially the false-colour variety), compression artefacts (e.g. banding and blockiness) and noise - because those can be distracting and not as easily dealt with later.

  20. 7 hours ago, kye said:

    I actually prefer HLG to a standard LOG profile.

    The reason is that HLG has rec709 levels of saturation and the main part of the image (everything below about 50%) and so when turning the image back into a 709 image from HLG you're not stretching out tiny differences in a flat LOG profile.

    The disadvantage of HLG in this sense would be the clipping of colours, but HLG retains the full DR of the camera so it will only clip on very very saturated colours and those will mostly be clipped due to being too hot (e.g. tail-lights) which would be clipped either way.

    I should have qualified my comment to say that it only related to my personal preference using 10-bit HLG and OMLog400 from the OM-1 - I've never used HLG or Log from other cameras. I'd actually prefer to shoot in a modified version of one of the standard picture profiles on the OM-1, but they are not available in 10-bit mode - HLG or Log are the only choices.

    It's interesting how different the log transfer curves can be on different brands and cameras (scroll down the pages to the step chart images) e.g.

    OM-1 - https://www.optyczne.pl/59.3-Inne_testy-OM_System_OM-1_-_test_trybu_filmowego_Użytkowanie.html

    GH6 - https://www.optyczne.pl/62.3-Inne_testy-Panasonic_Lumix_GH6_-_test_trybu_filmowego_Użytkowanie.html

    A6700 - https://www.optyczne.pl/79.3-Inne_testy-Sony_A6700_-_test_trybu_filmowego_Użytkowanie.html

    FX3 - https://www.optyczne.pl/46.3-Inne_testy-Sony_FX3_-_test_trybu_filmowego_Użytkowanie.html

    R7 - https://www.optyczne.pl/65.3-Inne_testy-Canon_EOS_R7_-_test_trybu_filmowego_Użytkowanie.html

    C70 - https://www.optyczne.pl/48.3-Inne_testy-Canon_EOS_C70_-_test_kamery_Użytkowanie.html

    S5ii - https://www.optyczne.pl/70.3-Inne_testy-Panasonic_Lumix_S5_II_-_test_trybu_filmowego_Użytkowanie.html

    XH2 - https://www.optyczne.pl/66.3-Inne_testy-Fujifilm_X-H2_-_test_trybu_filmowego_Użytkowanie.html

  21. ...or you could just create your own flat/pseudo log transfer characteristic in-camera by adjusting a standard picture profile (e.g. contrast, saturation, highlight/shadow curves) to give you a compromise SOOC/gradable format that fits your needs?

  22. 21 hours ago, SRV1981 said:

    that said, I saw Dehancer has a plugin for FCP and that may do the trick and make camera brand less of an issues so long as a baseline DR is present and AF is good enough 

    If you want useable SOOC video that looks reasonable when played directly, but which has high DR for grading if you want to, you could try shooting in 10-bit HLG?

    It's a compromise format that is designed to provide decent looking video on non-HDR displays, and full HDR on HDR-capable displays - see https://en.wikipedia.org/wiki/Hybrid_log–gamma . Note it uses Rec. 2020 colour space/gamut, so the colours will be distorted to some extent on a Rec. 709 display.

    KnightsFan said: 

    Quote

    The XT3 was great, but if I recall correctly there were issues with FLog in Resolve for a while, so I almost always used HLG and was happy with it.

    ...and I've also tried grading HLG (from my OM-1) and found it OK.

    I think Log is better for grading (than HLG), but Log is not very usable as SOOC video (unless you really like watching low-contrast/saturation video!).

×
×
  • Create New...