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#apertus IRC Channel Logs

2013/12/22

Timezone: UTC


23:01
guesst
in theory you can do flat field correction in the fpga
23:02
Bertl
that's not really the problem, and I think, for now, it can be done in the post processing (which wasn't done with this image)
23:05
guesst
i think the image got quite a lot of post to oversaturate the colors.. fpn should be fixed first :)
23:12
danH
joined the channel
23:13
Bertl
welcome danH!
23:14
Bertl
guesst: agreed, btw, in the image you referred to with sebastian, I see a similar horizontal and vertical pattern in the almost black background as we see with the CMV12k
23:14
Bertl
did you address this issue yet and if, how did you address it?
23:15
danH
changed nick to: danhanes
23:15
danhanes
Hello Bertl - Thanks for the welcome. I would like to join the development party - hw, sw, optics - how can I help ?
23:16
Bertl
sounds good, there is quite a lot to do, where do you see your specialities?
23:17
danhanes
Well, my IRC is a bit rusty :) But I have a good bit of C background (embedded), HW - logic, analog, smps. And optics.
23:18
se6astian
left the channel
23:18
Bertl
okay, did you take a good look at what we did so far? hardware and software wise?
23:19
guesst
Bertl: there is just noise from inadequate lighting
23:19
danhanes
Yes, I have read all of the IRC logs - really a great way to get a sense of the development trajectory so far. I've looked at some of the VHDL
23:20
Bertl
guesst: I clearly see 'fabric like' noise, i.e. row and column specific noise which isn't directly related to the lighting (I hope :)
23:20
Bertl
danhanes: okay, so you're comfortable with FPGA development as well?
23:21
danhanes
I would not say that I am comfortable, at least not at your level. I did a fair bit with some Altera parts a few years ago.
23:21
danhanes
I would like to get into the Apertus code, but I don't want to hold anything up.
23:22
Bertl
it is a steep learning curve in any case, but IMHO that's part of the fun :)
23:23
guesst
Bertl: there is one horizontal line i know of (it is not a production piece, just a sample) - and the noise you see is dynamic.. comparing several frames
23:23
Bertl
danhanes: so, on the harware side, there is not much left for the axiom alpha (the prototype), i.e. we are fairly complete there
23:23
danhanes
Indeed, I am working on understanding what you have. It will be a few weeks before I can contribute, I suspect.
23:24
Bertl
guesst: do you mind if I mark the issues I'm seeing and upload that somewhere?
23:24
guesst
do it
23:24
Bertl
because I'm curious where those artefacts come from, as we see them as well
23:28
Bertl
danhanes: that leaves the software part, for alpha at least, and there I guess the main part is FPGA after all, but we also have written and still need a bunch of helper tools to make it work properly
23:29
danhanes
probably best for me to start with some tools that are not on the critical path. I am sure there will be plenty to do on the FPGA side once I come up to speed.
23:30
Bertl
if you are interested in the FPGA part, I'd suggest to install vivado 2013.4 and check out this branch: https://github.com/apertus-open-source-cinema/alpha-software/tree/checker/cmv_des
23:30
danhanes
Yes, I was going to ask if you were using the ISE or had switched entirely to Vivado.
23:30
Bertl
it contains the (almost) up to date (I'll commit the pending changes soon) recent code to capture images
23:31
Bertl
do you have access to a zedboard or anything using a zynq?
23:31
danhanes
Not yet. Looks like a zynq is in the near future.
23:32
danhanes
I seem to remember a discussion on the '30 vs the '20 xilinx parts. Are you going to switch, and does the (affordable) vivado suppor it ??
23:34
Bertl
yes, we are making sure that the WebPack (i.e. the 'free' as in beer) version of vivado will cover the parts we are using
23:34
danhanes
great!
23:34
Bertl
we are looking at the 7030 and the newest addition the 7015
23:35
Bertl
because they both support 4 high speed serial tranceivers
23:35
Bertl
i.e. a little more than 6Gbit per channel
23:36
danhanes
Haven't looked at the 7015 - i'll check it out. 6G per channel is impressive. 6G SDI ?
23:39
Bertl
yes, that's the idea, but supports different protocols as well
23:39
guesst
where you would connect a 6G SDI ? :) there is barely 3G capable equipment
23:39
Bertl
ah, there is quite a number of recorders out there for dual 3G SDI and such
23:40
guesst
yes, if we forget the price :)
23:42
Bertl
it seems, you can get equippment for 2-4k USD already
23:42
Bertl
which is not so much if you want to record 4k at higher frame rates
23:43
guesst
which one?
23:56
Bertl
for example the Odyssey7 starts at 1300 USD
23:57
Bertl
granted, it wont do 6G SDI at that price :)
23:59
guesst
it hardly does 4k at that price :)
00:00
Bertl
sure, but the 7Q for example costs about 1k more and does quite well
00:00
Bertl
not saying those are the only ones, just as example
00:01
Bertl
I'm sure sebastian can give you a few more examples when he gets back
01:05
Bertl
danhanes: so, in general, if something is unclear, please ask, I might not always answering immediately but I'll make sure to get back to you
01:06
Bertl
for specific tasks on our todo list, there is a wiki page, and if you are interested in helping with the fpga part, contact me personally for small subprojects/tasks
01:09
danhanes
Thanks Bertl - I'm downloading Vivado now - slooooow. I look forward to getting to the point that I can help. I'll try to minimize the questions.
01:10
Bertl
yeah I always suggest, spend a few minutes on an issue/question and see if you can figure it out, if not, just ask, often it can be easily explained and saves a lot of time searching for a solution
01:11
Bertl
this is especially true for FPGA related stuff, I've spent a lot of time already figuring out trivial things, no need to repeat that without good reason
01:12
danhanes
Right. You guys have done a very impressive amount of work in a really short time. I'm impressed.
01:12
danhanes
Seems the Zedboards are in short supply - 3 weeks.
01:13
Bertl
also check out the microzed and maybe alternative zynq based boards
01:13
Bertl
I don't think that it really matter much, unless you plan to build/buy a sensor frontend as well
01:14
danhanes
I would hope to add a sensor at some point - but maybe best to get going with a microzed for now.
01:14
Bertl
for example the zybo looks quite interesting
01:14
danhanes
I'll have a look
01:14
Bertl
not sure what documentation is provided though, as it isn't open as the zedboard
01:15
Bertl
(but I guess they will provide a schematic at least, haven't checked yet though)
01:15
danhanes
I suspect I will need a little hand holding getting the platform up at first. I seems that is always the hardest part of any development - getting the tools working.
01:15
Bertl
an it features a HDMI interface, which is missing on the microzed
01:16
danhanes
HDMI seems critical
01:16
Bertl
in my experience it was kind of painless actually
01:16
danhanes
That's encouraging
01:16
Bertl
I downloaded the full version, installed it on my linux box (in a changeroot) and that's it for the tools
01:17
Bertl
the hardware driver is a little more tricky (for jtag) to get working first, but that is documented on the wiki (now)
01:17
danhanes
Good - maybe I will be up an running soon. What distro are you using ?
01:18
Bertl
mageia, but folks reported ubuntu and fedora as working as well
01:18
Bertl
you might also be interested in building one or two of the PMOD debug modules we designed
01:19
Bertl
they are quite useful in my experience, and they should for example work just fine on the zybo
01:19
danhanes
I use Ubuntu virtualized on my Mac. I may need to dust off the dedicated Linux box sitting in the corner.
01:19
Bertl
it might be a good idea, not sure, maybe the tools work on OSX as well
01:19
danhanes
I saw some material on the pmod boards. Simple LED arrays really helpful at times.
01:20
Bertl
yes, I've used them in countless cases to debug/visualize/check stuff
01:20
Bertl
I also got one of those OLS boards to check some things at higher speeds
01:21
danhanes
OLS ?
01:21
Bertl
http://dangerousprototypes.com/open-logic-sniffer/
01:21
Bertl
they are cheap and not very powerfull, but easy to handle and they work just fine for simple stuff
01:21
danhanes
Cool. More toys.
01:22
danhanes
Haven't seen that site before
01:22
danhanes
Good stuff there
01:23
Bertl
btw, the PMOD boards are available via OSHpark (the PCBs, you still have to solder on the parts)
01:24
danhanes
I was going to ask. I saw a reference to OSHpark in the logs. Do they have the files on hand - I can just order ?
01:26
Bertl
yes, you can directly order a pack of three (or multiples) for a really good price
01:26
Bertl
the link should be on the wiki, sec
01:26
danhanes
0603 LEDs ?
01:27
Bertl
http://vserver.13thfloor.at/Stuff/AXIOM/pmod_debug.{brd,sch,png}
01:28
danhanes
Thanks
01:28
Bertl
the schematic and board files are eagle
01:28
Bertl
http://vserver.13thfloor.at/Stuff/AXIOM/pmod_assembled_top_600dpi.png
01:28
Bertl
http://oshpark.com/shared_projects/OhXV1RwT
01:29
danhanes
Good stuff. I'll start setting up a dev environment.
01:32
danhanes
I've been thinking about getting Eagle. I use Altium at work, but I don't want to blur the work / play line. Using a very old Mac based program now, but time to switch. Any thoughts on KiCad
01:32
Bertl
yes, KiCad looks like it is getting somewhere
01:32
danhanes
Good to hear. I may try to install it.
01:33
Bertl
I would have used it, but I've been already working with eagle for quite a while now, so it was my first choice to get things done quickly
01:34
Bertl
for small projects both are quite fine, for larger things it becomes a little tricky
01:34
danhanes
Probably best to use something you are familiar with. If I remember Eagle is only $US 200 or so for the non-pro version. Is that what you are using and is it adequate? 120mm x 100mm boards ?
01:34
Bertl
the version I've been using for those is the free version
01:34
danhanes
Better yet.
01:34
Bertl
i.e. you can simply download, install and use it
01:35
Bertl
but yes, the simple commercial version is quite cheap, you can get one for less than 100 EUR IIRC
01:35
Bertl
(nothing compared to the altium prices :)
01:36
danhanes
Altium is nice, but overrated.
01:36
Bertl
I'm hoping that kicad will get there soon, now that cern has shown some interest
01:36
danhanes
Wasn't aware of CERN involvement. That would be a big plus.
01:37
Bertl
http://cernandsociety.web.cern.ch/technology/kicad-development
01:37
Bertl
http://www.ohwr.org/projects/cern-kicad/wiki
01:38
danhanes
You are a fount of knowledge ....
01:39
Bertl
you're welcome! :)
01:45
danhanes
Ahh - Vivado just finished downloading. Time to bail. Its early here (21:40). I think you are in Europe - do you sleep ?
01:46
Bertl
yes, I sleep occasionally, but I'm not in sync with the local timezone
01:47
Bertl
have a good night then
01:48
danhanes
Just as well, I suppose. Thank you for the introduction to the project. I look forward to working with you - hope I can help.
01:48
Bertl
looking forward as well, cya
01:57
danhanes
left the channel
03:41
jucar
joined the channel
05:22
jucar
left the channel
05:31
troy_s
Greets all.
05:31
Bertl
hey troy_s! how's going?
05:31
troy_s
Bertl: Finally finished for Xmas break.
05:33
Bertl
\o/
05:34
troy_s
Bertl: How goes Operation Struggle?
05:34
Bertl
quite well actually, I've revised the LVDS part, and should be done with that in the next days
05:35
troy_s
Bertl: Any luck in sorting out the noise patterns?
05:35
troy_s
Voltage or otherwise?
05:36
Bertl
well, we see three different 'noise' patterns at the moment
05:36
troy_s
Bertl: Hrm. I have seen the columns...
05:36
Bertl
a very prominent row and column noise pattern and a 'dark' noise pattern
05:37
Bertl
the row pattern will probably be easy to fix with the black columns, unless cmosis screwed up big time
05:37
jucar
joined the channel
05:37
Bertl
the column pattern I'm not sure, but we will be able to address/compensate that at least in post processing
05:38
troy_s
Flat field and dark frame applied?
05:38
Bertl
the 'row noise' is mostly caused by bad design on the cmosis side, there are known fixes (i.e. so that you do not need to compensate them)
05:38
Bertl
but unfortunately they disclosed the fixes after we designed the alpha prototype frontend
05:39
troy_s
Meaning?
05:39
Bertl
so we probably won't be able to apply them on this prototype
05:39
Bertl
according to cmosis, the sensors internal voltage reference is insufficient
05:39
troy_s
Awesome
05:40
Bertl
an external reference can be applied, compensating for most of the row noise
05:40
troy_s
Sounds like it might be worth looking at a new vendor...
05:40
Bertl
(note: there are two kinds of row noises)
05:40
troy_s
I certainly hope they will compensate in some capacity for the existing flawed sensors.
05:41
Bertl
I don't think they will change the sensor as it can be worked around in external hardware
05:41
Bertl
and to be honest, I prefer a sensor with a problem and known workaround over a sensor with a problem and no known work around :)
05:41
troy_s
Is there a method to fake this fix in the prototype imaging pipe?
05:42
Bertl
I think we can compensate for 99% of the 'noise' in post processing
05:42
Bertl
note that we haven't done any post processing in this regard yet, but most of the noise is either systematic or static
05:43
troy_s
I am wondering though, if it is too late for the prototype, if you can fake the exact process. Otherwise it is going to be hit and miss in the post pipe.
05:43
Bertl
so I'm confident we will get 'clean' pictures soon
05:43
Bertl
what currently worries me most is the third 'noise' style
05:44
troy_s
Which is?
05:45
Bertl
https://wiki.apertus.org/images/0/0f/Plot4ch.svg
05:46
Bertl
this is with different exposure times (just a simple histogram)
05:46
Bertl
and what worries me is that the noise doesn't seem to be gaussian
05:46
troy_s
Bertl: Which hump scare you? The middle?
05:46
Bertl
if you look at the 10s exposure
05:46
Bertl
you see that there are actually two maxima
05:47
Bertl
I first presumed that they might be because of differences in the colors
05:47
Bertl
but looking at the samples separated by color in a closeup:
05:47
Bertl
https://wiki.apertus.org/images/a/a7/Plot4ch-big.svg
05:48
Bertl
shows that it is some kind of sensel effect
05:49
troy_s
Very distinctive camel hump.
05:49
Bertl
we haven't done any analysis what happens if we remove the 'hot' pixels yet
05:49
troy_s
I am not certain what I am looking at however.
05:49
Bertl
maybe they cause the effect
05:49
troy_s
What image are you using for the analysis?
05:49
Bertl
I would expect an almost gaussian distribution on a 'dark frame' as was used for this
05:50
troy_s
So this is from a lens capped darkframe?
05:50
Bertl
and I definitely wouldn't expect it to show values aroun half the brightness after 10s dark exposure
05:50
Bertl
*around
05:50
Bertl
so, IMHO there is some stray light involved
05:51
troy_s
Out of interest, what do your evaluations show on Canon and Nikon images?
05:51
troy_s
And do the results compare on the perfect sensor versus the imperfect?
05:51
Bertl
I don't have access to unprocessed images from those, do you?
05:51
troy_s
I can get some raws.
05:52
Bertl
that would be great!
05:52
troy_s
But it would require at least a dcraw pass.
05:52
troy_s
Maybe dump a 16 bit tiff in linear.
05:52
Bertl
yeah, I know, they aren't really raw at all :)
05:53
troy_s
Bertl: Dark room with lens cap? Can you eradicate the light question?
05:53
Bertl
yes, the issue is a little trickier than that but we are working on a solution
05:53
Bertl
most of the stray light is caused by the LEDs on the zedboard
05:53
troy_s
I mean who knows... it could even be some sort of interference.
05:53
Bertl
I already figured out how to disable all but one, so we will have some tests on that soon
05:54
Bertl
I suspect a gap between sensor and lens mount or between lens mount and bajonet ring
05:54
troy_s
Actually
05:55
troy_s
Thinking on it
05:55
troy_s
That noise pattern should be perfectly linearized according to exposure
05:56
troy_s
So in theory, if it is errant light, it will hold according to exposure.
05:56
Bertl
hmm, no, I don't think so
05:56
Bertl
the distribution gets broader
05:56
troy_s
What do you mean by broader?
05:56
Bertl
i.e. the average width will be wider (statistically/gaussian)
05:56
Bertl
sec
05:56
troy_s
That is Greek damn you!
05:57
Bertl
give me a second to explain it, it's not that complicated
05:57
Bertl
http://vserver.13thfloor.at/Stuff/AXIOM/RAW/hist.svg
05:57
Bertl
you remember this one, yes?
05:58
Bertl
I did that way back to see how much external light affects the sensor
05:58
troy_s
No
05:58
troy_s
Oh yes.
05:58
Bertl
what you see there is an almost gaussian distribution (the shape of the curve)
05:59
Bertl
i.e. that is a mathematical function which is the result of statistical distribution as it happens for example with thermal noise
05:59
Bertl
just look at the shape
06:00
Bertl
now what you already see in this simple test is, that as the top of the 'bell shape' moves to the right, it also gets slightly smaller
06:00
Bertl
and if you look closely, the bottom of the bell also gets wider
06:01
Bertl
this is a property of statistical distribution
06:01
Bertl
i.e. it is expected and can be calculated
06:01
troy_s
All I want to know is whether that cat is alive or dead.
06:01
Bertl
same happens with longer exposure times
06:02
Bertl
i.e. the bell shape gets wider and less prominent
06:02
troy_s
Right. So the shape of the humps bother you?
06:03
Bertl
yes, the shape and the fact that they are around 1500-2000, because that is already half the range, i.e. 50% gray
06:03
Bertl
the total range in the plot is 0-4095
06:03
Bertl
(or at least it should be, not 100% sure actually, sebastian did the evaluation)
06:03
troy_s
So right smack dab in the middle of the sensel's receptive range is a camel?
06:04
Bertl
its more in the distribution
06:04
Bertl
i.e. it looks like there are a number of more sensitive pixels
06:05
Bertl
like 40% of all pixels are like 25% more sensitive than the other 60%
06:05
Bertl
and not up to 25% but exactly 25% ... and that sounds a little weird
06:05
troy_s
And is this a per channel eval?
06:05
troy_s
As in bad filter
06:05
troy_s
?
06:06
Bertl
yes, the rgb lines in the big plot are per channel
06:06
troy_s
Because when I look at that graph, the channels match perfectly.
06:06
Bertl
which is a good thing, yes
06:07
troy_s
Except that for some reason the voltage goes batshit in that middle exposure range?
06:07
troy_s
Have you ruled out infrared or other contamination from some source?
06:08
Bertl
the optic has an IR/UV cutoff, but that won't help with stray IR of course
06:08
Bertl
UV isn't such a problem with the sensor if you look at the spectral response
06:09
troy_s
Or temperature?
06:09
Bertl
temperature is actually quite nice since we have the boxed alpha with fan
06:09
Bertl
we keep about 4-5 degree above room temperature
06:09
Bertl
but we will do some more tests in this regard as well
06:10
troy_s
What is your guess and have you done a distribution analysis?
06:10
Bertl
no analysis yet and I have no clue except for stray light on the unusual dark frame results
06:11
Bertl
but my current focus is on getting the image capture solid, which as I said should be done in the next few days
06:11
troy_s
The odd shape certainly seems to hint that it might be something... but the curves match too damn perfectly.
06:12
troy_s
If it were errant light I wouldn't expect perfectly achromatic patterns.
06:12
Bertl
yes, well, it seems to be a sensel property or some strange effect in the readout
06:12
Bertl
in the IR range, the filters are basically all the same
06:12
troy_s
Would be illuminating to reduce that hump into a visual distribution if possible.
06:12
Bertl
so between 800nm and 1100nm you get almost the same response regardless of the channel
06:13
troy_s
A two dimensional distribution.
06:13
troy_s
Right... so it could be IR from an LED perhaps?
06:13
Bertl
for example
06:14
Bertl
that's why I'm disabling all leds (all but one faint green led) in the next version (from the zedboard)
06:14
troy_s
Can't you take a soldering nib to the green one?
06:15
Bertl
hehe, yeah wouldn't be a problem, but it would require to a) get the boxed alpha prototype back to me and b) mutilation of an otherwise perfectly fine zedboard :)
06:16
Bertl
and I think we can handle that one, the green ones are not really IR active
06:16
Bertl
and as I said, it is quite dimm and far away from the lens mount
06:16
Bertl
and if we need to, we can simply tape it over with a black tape
06:17
troy_s
Well fascinating.
06:17
troy_s
I hope se6 manages to get a heavily exposed IT8
06:17
troy_s
I suspect the images he has posted will be underexposed... that said I have yet to check them.
06:18
troy_s
And I suspect the current state of noise will mangle any matrix anyways.
06:18
Bertl
yes, please keep up the input regarding exposure/saturation/etc
06:18
Bertl
I guess if you tell him what to do, he should be able to get nice images
06:19
troy_s
The nature of color dictates that yellow greens etc live much higher in the luminance compared to blues and reds
06:19
Bertl
he has a colormeter available IIRC and some light sources
06:19
troy_s
So for a matrix to get a decent handle on the transform, the reds / blues need to be amped up quite high to red sufficiently.
06:20
troy_s
Yes. It cracked me up when he said he wouldn't trust the meter.
06:20
troy_s
Yet he appears to trust the kinos.
06:20
troy_s
Which are well known to be a shitbag of random.
06:20
Bertl
hehe, yeah, well, the meter was calibrated a bunch of years ago and never checked again, as fas as I know
06:21
troy_s
They shift color temps as they warm (about an hour) and they can skew all along the magenta / green axis.
06:21
Bertl
so there might be truth in both
06:21
troy_s
The tungsten light is about the smoothest distribution we can expect.
06:21
troy_s
So perhaps he can pop a bracketed set using a decent tungsten that has been metered.
06:22
troy_s
The Kinos just add more variables into our nightmare.
06:22
troy_s
Anyways... that Goren article is very solid.
06:23
troy_s
Once we have a matrix or LUT, I can sculpt an OCIO package for testing in any OCIO compatible app.
06:24
Bertl
great! so please talk to sebastian (either via email or here on IRC, he should be awake/around soon) and let him know what the best approach would be
06:25
Bertl
I think it might also be good to use some daylight (or what's left of it at this time of the year :)
06:25
troy_s
Right now, the best thing is to get a big brainer like you to eliminate the errant noise issues
06:25
troy_s
Yes.
06:25
Bertl
I've seen that in my scene* images
06:25
Bertl
even really low daylight gives very pleasing results
06:25
troy_s
But noise is a huge issue. Then I would suspect getting a decent interpolation. Or perhaps just use some sensel skipping and use a ‘pure’ set of sensels.
06:26
troy_s
The thing we want to get to are a smooth spectro (nigh on impossible with synthetic light emitters)
06:26
Bertl
yeah, don't worry, I'm confident we'll get that sorted, and for the calibration, the noise shouldn't matter at all
06:26
troy_s
and rid ourselves of the synthetic distributons (noise, interp, etc.)
06:27
Bertl
that's why I was so fond of daylight (suddenly :)
06:27
Bertl
but tungsten has a really smooth spectrum indeed
06:27
troy_s
We can always gaussian the patches a smidge if need be to normalize the metered regions.
06:27
troy_s
Tungsten and daylight are hard to beat.
06:28
Bertl
btw, I was wondering, from the color PoV, is there any point in using (somewhat) pure sources of color?
06:29
troy_s
And frankly a decent matrix or LUT for 5500 and 3200 covers about 99.5% of shooter needs to start.
06:29
troy_s
Bertl: Pure?
06:29
Bertl
I'm asking because it would be fairly trivial to get a whole bunch of LEDs with very narrow emission bands
06:29
troy_s
Oh... that might be interesting to experiment with. It is a little like audio though.
06:29
Bertl
and it would also be trivial to shine them on/through white paper
06:30
troy_s
We want a perfectly straight line similar to what tungsten or the sun offers. If we use many ‘humps’ of light, where the crossovers land can mangle your evals.
06:31
troy_s
The secret is the IT8. So that is where our reference of ‘color’ is.
06:31
troy_s
It is all somewhat arbitrary as color is really synthetic; a psychophysical phenomenon as the color nerds call it.
06:32
troy_s
Ok.
06:32
troy_s
Must install another kitchen strip of lights. Joy.
06:33
troy_s
Fascinating chat Bertl. Thanks. Very illuminating. Keep me abreast of your noise work and research.
06:33
Bertl
will do, have fun and thanks in advance!
06:34
troy_s
Chat soon!
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07:59
Bertl
off to bed now ... have a good one everyone!
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08:19
se6astian
good morning
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09:13
philippej
Hi everyone !
09:17
se6astian
hello!
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10:15
philippej
how to setup a test lab for cheap : http://www.imatest.com/docs/lab/#lighting
10:15
philippej
I'd say that using tungsteen is the best way to avoid trouble
10:16
philippej
as we know the way it makes light, burning a filament, a bit like sunlight, and provides the most efficient color rendition of articfical lighting. Even if kino tubes are rated 90% color rendition index, it's nowhere near the 99% we get with tungsteen. Imho
10:25
se6astian
interesting link, thanks
10:26
philippej
Bertl, will you able to provide the external vref on the current prototype's hardware?
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13:39
FergusL
HI here
13:40
FergusL
wow, I'm sure that huge Bertl VS troy_s backlog will be full of good information, reading now
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se6astian
the apertus° history now also accessible in a new language: https://www.apertus.org/zh-hans/%E9%A1%B9%E7%9B%AE%E5%8E%86%E7%A8%8B :D
14:04
FergusL
very interesting chat last night
14:05
FergusL
quite greek to me though
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15:11
Bertl
morning everyone!
15:16
se6astian
hello!
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philippej
heya
15:46
Bertl
whoa, full house today :)
15:47
Bertl
and yes, I agree, tungsten or daylight is probably our best option for the IT8 chart atm
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se6astian
good night!
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