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08-01-2014, 01:39 AM   #16
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You'll get different bitrates when select the video IQ as well (*** / ** / *)

08-01-2014, 12:40 PM   #17
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QuoteOriginally posted by Steve.Ledger Quote
You'll get different bitrates when select the video IQ as well (*** / ** / *)
Well, I guess we only shoot with ***

Still, I don't get why we have the quality option, even the highest option it's bad...

That's quite a challenge for us.

By the way, tomorrow I will be shooting a meeting of a Mitsubishi owners in a car track, so I hope to get some good footage, no sound though, only music.

I will shoot with the settings mentioned above, in muted mode with the contrast a bit down. I will try to do some post.
08-01-2014, 02:43 PM   #18
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QuoteOriginally posted by JohnnyXD Quote
Well, I guess we only shoot with ***

Still, I don't get why we have the quality option, even the highest option it's bad...

That's quite a challenge for us.
There's more to video quality than just bitrate.
There's no appreciable visual difference between the three qualities of video from the K-01/K-50. Only the file size changes, the footage is rubbish at all IQ levels. This I have tested a number of times and nothing has convinced me that PENTAX APS-C cameras can record decent quality video.
08-02-2014, 12:58 AM   #19
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I'd say if you can get the look you want (except for sharpness) in camera that's good, because when grading the recorded footage you'll have limited data to push around. That's for the h264 based cameras. MJPEG ones have plenty of data to spare IMHO.

As for the quality not being good regardless of bitrate:
At least a while back the nvidia h264 GPU based encoder was way inferior to the (slower) x264 that is CPU based. Despite using the same bitrates. There are big variations with x264 too, depending on the quality settings and thus encoding speed. I'm using a tweaked version of placebo (optimized for preserving gradients) with the latest x264 version at 10 bit. That gives me very good compression with very small files (I recoded my The Dark Knight Rises Blu Ray and ended up with < 4 Mbit (with a color noise filter and a very subtle denoiser)! It looks almost as good as the original file, you'd have to look closely)). In camera the encoding MUST happen much faster on much lesser hardware. Even though it is dedicated hardware meant for h264 encoding.

I fear what has happened was that the encoder that Fujitsu designed is buggy (like that nvidia thing) and makes mistakes. IIRC I noticed artefacts when something with a gradient moved. Say someone wearing a same color shirt. Maybe someone can try that? First under challenging conditions, then in front of a white background, with lots of light/no noise. Make it as easy as possible for the encoder.

I could also imagine that they have set a fixed quality setting with a cap at 24 Mbits or so, instead of a constant bitrate of 24 Mbit. And they set the quality too low, so that it doesn't make full use of the bitrate.

08-02-2014, 04:10 AM   #20
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I accepted that the K-7 was a bit naff with video as it was their first, but that was 2009. Five years later they have managed to actually do much worse, not only in terms of the codec and bitrates used, but the video stabilization choice. The word 'crippled' comes to mind when considering Pentax DSLR/DLSM video performance.
08-02-2014, 05:08 AM   #21
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QuoteOriginally posted by Steve.Ledger Quote
I accepted that the K-7 was a bit naff with video as it was their first, but that was 2009. Five years later they have managed to actually do much worse, not only in terms of the codec and bitrates used, but the video stabilization choice. The word 'crippled' comes to mind when considering Pentax DSLR/DLSM video performance.
funny, I went on a hiking trip two weeks ago and as an experiment, i decided to shoot all handheld, with SR on :-) to make my own life difficult...
I'll share it later on. I find the codec of the K3 actually not too bad combined with the userfriendliness of a pentax. regardless of bitrate.
There is not a single dslr out there that has convinced me on all features yet.

QuoteOriginally posted by JohnnyXD Quote
I will shoot with the settings mentioned above, in muted mode with the contrast a bit down. I will try to do some post.
If i am not too late answering, just pull everything all the way down. sharpness, contrast, saturation... You'll be surprised how much you can do in post.
the free plug in "magic bullet colorista" is nice to use..
08-02-2014, 05:14 AM   #22
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QuoteOriginally posted by Derwin Quote
Purely in terms of maximising data-rate and minimising compression artefacts, and lets also set aside for the moment any considerations regarding the creative or technical limitations this may put on your available options in post, is there any advantage to be had in shooting direct to a tweaked-to-taste B&W picture style in-camera?
Only if you're delivering B&W product - you can't put the colour back in.
De-saturate by all means, but B&W means B&W, not simply colour reduced.

On the CoDec, pricture styles, and the like,... This afternoon I hooked up my K-01 to my Canopus ADVC100 via the camera's analog and sent the firewire connection in to Adobe OnLocation to display the waveform and histogram monitors,.. And had another camera recording the screen.
With the K-01 looking outside, I went through the Natural and Muted picture styles, and adjusted the Contrast and High/Low Key adjust to see what really happens.

Contrast up stretches white and black away from each other, down compresses them towards each other.
High/Low Key adjust works more like a screens Brightness control, more then like a TV camera's Gamma Knee - which is what I thought it did before.
So, by setting the exposure (ISO/Iris/Speed) to gain correct exposure overall, reducing Contrast lifted the blacks and lowered the whites, and then lowering the High/Low Key allowed me to reduce the over exposure of the sky while maintaining the overall correct exposure of the garden.

I have yet to check the vision the K-01 recorded at the time in Edius to compare the waveforms, but it's my opinion that reduced Contrast is better at preserving more information within the range of the standard video signal before compression.
High/Low Key biases the available space within the signal to have either more space for the highlights, or more for the Lows, at which point it becomes more a matter of how bright or dark your scene is - shooting outdoors in daytime, lower the High/Low Key, shooting in a dark room or at night, raise the High/Low Key to get more information in the dark areas of the frame.

I'll post the video of what I was recording to my Vimeo once I put a decent narration over it..... maybe with someone elses voice.
08-02-2014, 05:14 AM   #23
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QuoteOriginally posted by Derwin Quote
I'm wondering if that limited 20Mbps can be put to better use if it's just mapping luma info and not chroma, though I have no idea what the processing pipeline is like and whether or not this would realistically bring any benefit. Any thoughts?
I read an article once regarding best settings on my sony a77 (24mbps). Can't find it anymore on the web, but basically they compared quality coming out from the different styles. B&W gave the best quality compared to the others. Don't ask me what their basis of comparison was. Since then i tend to keep saturation very low. You only need little color information to get going in post..

08-02-2014, 05:24 AM   #24
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QuoteOriginally posted by Steve.Ledger Quote
There's no appreciable visual difference between the three qualities of video from the K-01/K-50. Only the file size changes, the footage is rubbish at all IQ levels. This I have tested a number of times and nothing has convinced me that PENTAX APS-C cameras can record decent quality video.
Steve: with which firmware?
I noticed some pretty big differences with the K-01 going from v1.03 to v1.04 - no more macro blocking errors and better 'grain'.
v1.05 was only a slight difference - The best I can explain it, was that to my eye, there was less banding across luminance gradients on walls in the background of the frame.

I compare what I see on the LCD and external (analog) monitor, to what I saw when working with ENG cameras, and then what the footage looks like in Edius, and I'm pleased with the image quality for the price of the camera and lenses.
But,... I really do want Pentax to implement a much higher data rate to preserve fine detail better, or use a CoDec that has less compression, preferably No inter-frame compression.
08-02-2014, 09:39 AM   #25
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QuoteOriginally posted by PiDicus Rex Quote
So, by setting the exposure (ISO/Iris/Speed) to gain correct exposure overall, reducing Contrast lifted the blacks and lowered the whites, and then lowering the High/Low Key allowed me to reduce the over exposure of the sky while maintaining the overall correct exposure of the garden.
interesting. I saw the option, but never knew what to do with it..
Now it makes sense and at first sight, useful.
08-02-2014, 12:34 PM   #26
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QuoteOriginally posted by PiDicus Rex Quote
Steve: with which firmware?
1.04
I didn't update to 1.05 as it essentially only adds support for the HD PENTAX-DA AF REAR CONVERTER 1.4X AW.
Not something I'm every going to buy.
08-03-2014, 02:31 AM   #27
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1.04 should give you pretty good results, better then a lot of other cameras.
08-03-2014, 03:11 AM   #28
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I saw no mention of improvements to video quality, only mention of the converter support.
Tell me, what difference does 1.05 make to video over 1.04??

EDIT: Note that I have 1.02 for the K-50 installed (the latest) and the video quality is the exact same as the K-01.

Last edited by Steve.Ledger; 08-03-2014 at 04:34 PM.
08-03-2014, 04:28 PM   #29
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QuoteOriginally posted by PiDicus Rex Quote
1.04 should give you pretty good results, better then a lot of other cameras.
This is interesting, improving the codec after the release of the camera. I can hope Ricoh/Pentax will entertain the idea on the K3 as well.
08-04-2014, 12:19 AM   #30
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No inter frame compression should only help with editing, right? Otherwise it uses up more bitrate for the same quality. I've used up to 1000 frames between I frames and got good, constant picture quality. No degradation whatsoever.
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