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Interceptor121

Member Since 25 Jun 2011
Offline Last Active Today, 12:59 PM
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#360601 Does my color right? Nusa Penida WA shoot with GH4

Posted by Interceptor121 on 28 April 2015 - 10:32 PM

You have a bit too much purple tint. I sit in the middle of the camp as I use filters with or without custom white balance. I don't want the clips to look as my eyes saw it as otherwise they would look green and blue unless I have lights but also not to exceed on the other side. I don't change saturation in post never. If you didn't have a filter and you are not happy with the colours after custom white balance you may need to change the picture settings to push blue further. If I do any editing is sometimes to remove the cast not to push the colours further


#360454 How important is underwater tripod?

Posted by Interceptor121 on 25 April 2015 - 03:06 AM

This is I think the solution moses is using. We came up with this idea two years ago.

 

http://interceptor12...s-and-monopods/

 

I have also used the monopod option which is just having ball segments on the bottom of the tray and a single 8" arm segment on the back.

 

For macro it is essential this is a trip to lembeh few years ago where I used this set up

 

The octopus are hand held but look at the smaller stuff (not on a wall)




#357868 Trip Video: 01/30/2015 Los Coronados Islands

Posted by Interceptor121 on 15 February 2015 - 02:07 PM

Nice work Bob! What color profile did you use? The color turn out well!

 

Bet 5c is something like standard or scenery and not anything advanced

White balance looks very accurate not sure if this was custom or presets but very good actually looking at the saturation maybe there is even a filter involved?




#357851 Getting the best results from YouTube / Vimeo (1080, 4K etc...)

Posted by Interceptor121 on 15 February 2015 - 02:25 AM

Download of the second 720p clip from youtube not a lot of information but still few key bits

ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High@L3.1 Format settings, CABAC : Yes Format settings, ReFrames : 1 frame Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 4mn 24s Bit rate : 2 383 Kbps Maximum bit rate : 6 694 Kbps Width : 1 280 pixels Height : 720 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 25.000 fps Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.103 Stream size : 75.1 MiB (92%) Encoded date : UTC 1904-01-01 00:00:00 Tagged date : UTC 2014-09-09 01:57:15

 

Key facts:

1. Only 1 reference frame which is low vs 4 of Vimeo. Also youtube does not use B frames

2. Bitrate is not fixed at 2383 but both average and max are lower than vimeo

3. Profile is still high

4. File size very similar to vimeo

 

Key conclusion at the same bit rate the equivalent Youtube file will look much worse than Vimeo due to inefficient compression settings of youtube




#357850 Getting the best results from YouTube / Vimeo (1080, 4K etc...)

Posted by Interceptor121 on 15 February 2015 - 02:16 AM

I just downloaded a 1080p HD clip from vimeo those are the settings

 

ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High@L4.0 Format settings, CABAC : Yes Format settings, ReFrames : 4 frames Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 5mn 33s Bit rate : 4 500 Kbps Width : 1 920 pixels Height : 1 080 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 29.970 fps Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.072 Stream size : 178 MiB (95%) Writing library : x264 core 142 r11 24e4fed Encoding settings : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=48 / lookahead_threads=8 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / stitchable=1 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=infinite / keyint_min=29 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=2pass / mbtree=1 / bitrate=4500 / ratetol=1.0 / qcomp=0.60 / qpmin=5 / qpmax=69 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=4950 / vbv_bufsize=13500 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00 Encoded date : UTC 2015-02-12 11:41:43 Tagged date : UTC 2015-02-12 11:41:43
 

This is a 720p clip

ID : 1 Format : AVC Format/Info : Advanced Video Codec Format profile : High@L3.1 Format settings, CABAC : Yes Format settings, ReFrames : 4 frames Codec ID : avc1 Codec ID/Info : Advanced Video Coding Duration : 4mn 24s Bit rate : 2 500 Kbps Width : 1 280 pixels Height : 720 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 25.000 fps Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Bits/(Pixel*Frame) : 0.109 Stream size : 77.9 MiB (95%) Writing library : x264 core 142 r11 24e4fed Encoding settings : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=48 / lookahead_threads=5 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / stitchable=1 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=infinite / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=2pass / mbtree=1 / bitrate=2500 / ratetol=1.0 / qcomp=0.60 / qpmin=5 / qpmax=69 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=2750 / vbv_bufsize=7500 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00 Encoded date : UTC 2015-01-29 19:31:53 Tagged date : UTC 2015-01-29 19:31:53 Color primaries : BT.709 Transfer characteristics : BT.709 Matrix coefficients : BT.709 Color range : Limited

 

For those people that don't understand anything of the gibberish up there those are the key points:

  1. Vimeo uses 2 pass encoding
  2. VImeo also uses max bit rates and buffer sizes vbv_maxrate=2750 / vbv_bufsize=7500 for 720p and vbv_maxrate=4950 / vbv_bufsize=13500 for 1080p which means
  3. Average bitrates are 2500 for 720p and 4500 for 1080p
  4. Motion estimation parameters are medium me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1
  5. Vimeo uses plenty of B frames and P frames options bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2

 

So in short vimeo will encode anything you throw at it (actually using X264!) the bitrates and file sizes are on the small size however they push H264 compression pretty hard so the small size is not such a bit problem as it looks.

Motion estimation and other settings are not particularly great however as they use 2pass encoding the outcome is still OK

 

In short I give my blessing to Vimeo the compression is efficient and the files are small so will look decent on a computer screen, a bit less so on a large TV set but still pretty good




#357823 GH4 - Nauticam Macro Lens/Port Thoughts

Posted by Interceptor121 on 14 February 2015 - 09:28 AM

Those are two shots with PZ-14-42mm at 42mm end and Inon UCL-100 on the GX7 for the GH4 you are looking at 26mm horizontal after 4K crop and 1.5cm height

For me this is already very small

Attached Images

  • UCL-100 42mm.jpg
  • UCL-100 42mm Diagonal.jpg



#357739 Choose your weapon: SLR versus video camera for filmmaking

Posted by Interceptor121 on 12 February 2015 - 12:24 AM

Personally I think the conclusion in that article is wrong on a number of account. In the non pro segment I have operated a sony rx100 and panasonic lx7 exactly like a camcorder with wet lenses and shooting macro and wide in one dive. In the 4:3 segment I am just about to do the same with the GX7 where I can zoom through a wet lens with no soft corners. I could do the same with the GH4 and with the 14-42 pretty much use it as a camcorder. True only difference is depth of field that is less however other than macro where this becomes a challenge (forget about zooming in from close to macro the focus won't hold) at wide end is irrelevant as depth of field is pretty big and for close up less depth of field actually is much better to isolate the subject. I am sympathetic with people switching from small chip camcorder to SLR as they have a hard learning curve but there are plenty of option. I have few professional studio videographers that got in touch with me to buy an RX100 or LX7 and the four third segment has just been approached with an SLR angle until now except Peter rowland that uses wet lenses nobody else does until now. It is also true that unless you go to raja ampat it's rare to see barracudas schooling and a Pygmy on the same dive so the one size fit all is also a bit overrated. Shooting SLR style is very technical exactly like shooting stills is but it doesn't have to be that way for 4:3 so advanced compacts four thirds and go pro take the consumer segment and maybe a bit of semipro/pro with GH4 and entry level camcorders are dead. To the comment of scubabob Gates should spend their R&D resources looking at how they are going to survive otherwise they will be out of business in 2 years best case. I have seen this happening in other industrie s and would not be the first time


#357735 GH4 - Nauticam Macro Lens/Port Thoughts

Posted by Interceptor121 on 11 February 2015 - 11:12 PM

Very rough test with the Olympus 60mm macro in the housing in air. Minimum size to fill the frame:

60mm only: 13mm subject at 5cm distance
Subsee +5: 10mm subject at 2.5cm distance
Subsee +10: 9mm subject at 1.5cm distance
Subsee +5 and +10: 10mm at whatever range (working distance just 0 to 3cm)

Personal Conclusion: Worth taking the Subsee +10 alone for a bit more magnification (about 30%), but not really the +5.

Basically wet diopters seem of more value for non-macro lenses.


The diopter is effective in shortening the working distance in water however it only shortens the actual distance from the port to the subject not the total working distance.
a lens like the 60mm has a minimum distance from the sensor of 19 cm however only 5cm are left between the port and subject in water those become 6.65 cm. The lens by itself has already 15 diopters and the focal length is now 80mm a +5 only has a 1.5 cm net benefit
However if you have the pz 14-42 that has 20cm outside the port in water the equivalent distance becomes 26.6cm a +5 brings this down to 8.8cm which is 2.34x closer
In short the diopter only brings a benefit is it is more powerful than the lens on its own. As a rule of thumb you want something at least with the same power of the lens in air. Example 60mm you need a 15cm to make a real difference however you maybe left with no distance. Pz 14-42 benefits start at +5.


#357686 Choose your weapon: SLR versus video camera for filmmaking

Posted by Interceptor121 on 10 February 2015 - 02:50 PM

I think this is a good article overall but tries too hard to justify the author's own bias

I have been shooting underwater video with compact Sony RX100 and Panasonic LX7 for over 2 years now and the results are not awful, though I am not planning to do competitions. I run my blog site almost entirely focussed on underwater video with compacts and I get around 50,000 hits per year so there is an audience out there.

The high quality compacts have eliminated the entry and mid level camcorders it is true but other than some ergonomics I don't believe at all the image quality was ever great with those devices more importantly a compact camera is small both on land but especially in water.

 

It is true that DSLR make it harder to focus etc but having less depth of field is actually quite nice depending on what you shoot and the quality is not lacking

 

More importantly the article misses completely micro 4:3 as a category and this is strange considering that BBC is using those for the oceans project and so are doing other media houses with the GH4.

 

I can zoom the whole range in a wet wide angle lens with the GX7 and then use diopters for super macro the lenses are stabilised so some of the advantages of camcorders are not exclusive anymore




#357147 Panasonic LX-100 Nauticam housing

Posted by Interceptor121 on 28 January 2015 - 11:41 PM

On comment a chromatic aberration at 24mm you probably have a mix of ca and pincushion distortion. A flat port with such wide lens is always a problem. For what concerns your subsee shots the magnification seems little. Should be able to do better than that. Did you use the macro focus as that will make a difference of another diopter


#357077 Panasonic LX-100 Nauticam housing

Posted by Interceptor121 on 27 January 2015 - 03:25 PM

The subsee is only 52mm wide as the adapter is far away from the lens I would check for vignetting. Would expect it to vignette at least until 50mm if not more. If the nauticam is 67mm it would be a safer option


#356925 Ikelite Housing for Panasonic LX100

Posted by Interceptor121 on 24 January 2015 - 04:09 AM

Fantasea have a new version that is the copy of the nauticam but in plastic


#356675 Has anyone used a Wet mate mini dome or an air dome with a micro 4/3?

Posted by Interceptor121 on 16 January 2015 - 01:35 PM

I am not quite clear about the physics behind it so I wonder if anyone has tried a wet mate like the Nauticam one or a similar solution with a flat port on a macro 4\3 to restore the air field of view???

 




#356561 Wide angle with GH4 and 14-42mm PZ lens

Posted by Interceptor121 on 13 January 2015 - 10:39 PM

The short port is flat and requires the inon wide angle lens. The dome port has got no lens it's just a dome to restore airfield of view. I have told the dome works in the 24-40mm range but this needs to be checked more


#351946 Latest video from Malta Comino and Gozo incl Tuna Farms

Posted by Interceptor121 on 24 August 2014 - 07:47 AM

Pretty much all straight from the camera, no exposure corrections around 40" have minimal color correction (caves and shots with lights)