Testing different prices HDMI cables. Suggestions welcome, results will be published here.

So you aren't going to update the thread with pictures, when you get the cables? :o
 
Wow, this whole thread has been a testiment to idiocy and stubborn mindedness. If you saw a massive difference in the shop, the sales guys tricked you. It's life, it happens all the time. You wouldn't go to a fair ground and try to tell people gravity is different there because the cans didn't fall off the shelf when you hit them with a ball.

You think theres a difference, you want to test it, fair enough. Just don't argue with people who know better than you, as you'll just continue to come across as an idiot.

What the thread should have been was:

RB: Tested some HDMI leads and there was a difference, so i'm going to test some out.
Reply: There shouldn't have been, i think they conned you. It's not actually possible for these reasons [insert fundamental workings of hdmi standards here]
RB: Ah, well i can't really argue with how it actually works. Guess i must have been duped big time. Still, the cables are on the way, might as well try.

[/end thread]
 
EVH said:
So you aren't going to update the thread with pictures, when you get the cables? :o
Click to expand...

It seems people are pushing very hard for that to be the case and after 5 pages it really is getting very hard work.

There have been a couple of people saying they would be interested and quite a few more saying "it's pointless don't bother or if you do we will just debunk them anyway we can".

If there is a strong desire for me to post them then I am more than happy. If more people would rather I didn't, you know, to save me wasting my own time, then I will just make a link available to those who are interested.

If you are interested then let me know here or via email in trust and if you don't then also let me know. At least I can have a gauge on how much interest there may be. At the moment I only know of a couple or so people who would be interested and many more who are not.

RB
 
krisboats said:
Wow, this whole thread has been a testiment to idiocy and stubborn mindedness. If you saw a massive difference in the shop, the sales guys tricked you. It's life, it happens all the time. You wouldn't go to a fair ground and try to tell people gravity is different there because the cans didn't fall off the shelf when you hit them with a ball.

You think theres a difference, you want to test it, fair enough. Just don't argue with people who know better than you, as you'll just continue to come across as an idiot.
Click to expand...

Demon stated the only way the effects can happen in post #15
The only way you are going to see a difference (assuming no sparklies/picture drop out) is if
1. The resolution is changed when swapping cables
2. The colour depth is changed when swapping cables
3. You deserve to be on rogue traders and you switch to an analogue cable whilst mis-representing it as a 'cheap HDMI cable'..
Click to expand...

In post #58 I quoted from HDMI.org where it stated that the first two items can be affected by a (faulty) cable.

EDID Implementation Issues

One key area of interoperability for HDMI-connected devices is the ability to effectively communicate EDID data via the DDC channel. If the sink device (the HDTV or projector) has its EDID ROM coded incorrectly, or if a source or repeater device fails to read it properly, the system will fail in its attempts to auto-negotiate the proper video and audio modes. Symptoms of this problem include incorrect color space and/or the wrong resolution.
Click to expand...

Demon explained his experience with E-DID issues in post #66 but notes it is very unlikely.

I did some work on here for people having issues with their Monitors not working with Xbox 360's over HDMI, It was down to incorrect EDID information, so I had to re-code and write it to the monitor to get it to work, I tried the monitor with 4 BR players, a 360 and PS3, my findings where that with incorrect EDID information, the BR players and the 360 all defaulted to 576i, the PS3 just ignores EDID and outputs whatever it's set to. I think in the interestd of fairness, the change to SD resolution is so large in terms of PQ that it would become immediately obvious, and on a scale that is as obvious as the image having sparklies or not being present at all..
Click to expand...

Demon was then kind enough to go in to more detail in post #74
To be honest, the consoles seem to change their behaviour between firmware updates (and why these monitors suddenly stopped working). At the time, you could set the PS3 to 'auto/720/1080', selecting auto just set the display to 720p as this is their most compatible resolution (A bug in scaling hardware means some games cannot be output at 1080p), it never changed to 1080p on it's own, unless I explicity set 1080p in the video options. The 360 used to ignore EDID and allow manually setting the resolution, then one firmware update brought 'auto-detection', and some monitors stopped working as they didn't have 1080p as a supported resolution in their basic EDID info, so the 360 defaulted to SD, I believe they may have changed it back again since.
But categorically all BR players I've tested in their default state, all default to SD when no or corrupt EDID information is present, EDID has a checksum to allow small amounts of corruption to be detected.
Click to expand...

Up to that point it was all fairly interesting and then for some reason it descended back to the 'it is not possible and you are just trying to prove more expensive cables are better than cheap ones". In my error I kept responding to try and make it clear that is not the case. Now we are up to post #146 with nothing but ignoring the points above and people stating categorically that it cannot happen with a few new people jumping in from time to time and rolling us right back to the beginning again. Added to this was the difference in defenition between myself and Demon on the term scam which Demon cleared up much later.

Yes I fully agree that the shop misrepresented why the picture changed either deliberately or through ignorance.

krisboats said:
What the thread should have been was:

RB: Tested some HDMI leads and there was a difference, so i'm going to test some out.
Reply: There shouldn't have been, i think they conned you. It's not actually possible for these reasons [insert fundamental workings of hdmi standards here]
RB: Ah, well i can't really argue with how it actually works. Guess i must have been duped big time. Still, the cables are on the way, might as well try.
[/end thread]
Click to expand...

That would have been great if the full fundamental workings of the HDMI standard were highlighted, not just the sending of physical video and sound data.

At post #74 we more or less got to the full reply. There has been a lot of confusion on the HDMI standards, HDMI cable standards and terminology in between.

So how about we sum up in one last post and leave it at that until I can finally get the photos ?.

Something light. A brief not on HDMI standards being about the chipsets in the devices. About HDMI cable ratings (cat1/cat2, Single link/dual link, normal speed/high speed). Something about corruption of signal on the cable (no picture, flikering picture and/or sound, artefacts such as white sparkles or lines). Note about if anyone shows you any different issues with the picture apart from those previously mentioned then it is a faulty device/cable or a deliberate manipulation. Highlight about if someone tells you it is due to cable price then they are misrepresenting either deliberately or through not understanding the HDMI communication system.

Demon, would you be happy with the above summing up paragraph ?. Would you like to put it together as the appointed expert ? I have no issues with any of that.

I also fully apologise to everyone for my part in this thread running out of control. I would have loved for it to have gone exactly the way Krisboats stated.

RB
 
if you are going to take photos, you need to set the camera up correctly (exposure) using a totally white screen so that white on the screen is white on the camera. I know that the photos arent supposed to be perfect but when they are madly under-exposed they cut a lot of detail out. the sort of detail that may or may not be spotted when swapping cables.
 
james.miller said:
if you are going to take photos, you need to set the camera up correctly (exposure) using a totally white screen so that white on the screen is white on the camera. I know that the photos arent supposed to be perfect but when they are madly under-exposed they cut a lot of detail out. the sort of detail that may or may not be spotted when swapping cables.
Click to expand...

Agreed James. I have been looking at calibrating the projector and will afterwards calibrate the exposure to get closest image I can from what I can see. The sample picture is very underexposed and that comes partly from looking at the shots a couple of days after they were taken and not right away. Using the projector over the last weekend, the black on the image should in no way match the black of the screen surround or that of the wall behind. If I get a chance tonight I will try for a closer approximation. Oh I have also dug out the remote release finally.

RB
 
RimBlock said:
Agreed James. I have been looking at calibrating the projector and will afterwards calibrate the exposure to get closest image I can from what I can see. The sample picture is very underexposed and that comes partly from looking at the shots a couple of days after they were taken and not right away. Using the projector over the last weekend, the black on the image should in no way match the black of the screen surround or that of the wall behind. If I get a chance tonight I will try for a closer approximation. Oh I have also dug out the remote release finally.

RB
Click to expand...

I believe your camera's dynamic range isn't sufficient to capture both dark and white levels of a video image, but you could take two shots, one over exposed, one underexposed to catch both ends..
And you'll need to use the camera in 'manual' mode and set the same aperature/shutter speed/iso for each shot for fairness.. You'd ideally want to use a commercial BR or PS3 playing one of the standard test BR's that have colour charts and resolution test charts etc..
 
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Demon said:
I believe your camera's dynamic range isn't sufficient to capture both dark and white levels of a video image, but you could take two shots, one over exposed, one underexposed to catch both ends..
And you'll need to use the camera in 'manual' mode and set the same aperature/shutter speed/iso for each shot for fairness.. You'd ideally want to use a commercial BR or PS3 playing one of the standard test BR's that have colour charts and resolution test charts etc..
Click to expand...

I have taken a couple of test shots tonight and the results are interesting. I was also thinking the same as you with two shots. Using a 720p version of Austin Powers, the spy that shagged me I have found that the image captured is a lot more dynamic than can be displayed when viewed in RAW format. Changing the exposure in lightroom (+1/-1) brings out detail in the dark areas / detail in the light areas. A shot taken from Transformers (1080p) seems good but I really need the colour calibration sorted. I can tune the brightness / contrast to an extent but the colour is a lot trickier without a proper reference material to use. Guess it will be a copy of video essentials HD then. What I can get a good level on is the difference between the black image border of the picture and the black of the screen non-reflective parts.

Again if anyone knows of a decent place I can put the raw files I will share so people can have a look and see what I mean. Photobucket wont take CR2 and rapidshare etc have the timers which are a PITA for non-subscribers.

RB
 
Oh and another thing I noticed which is a bit strange. I spotted the A.C.Ryan was running at 720p last night so changed it to HDMI auto. After taking the Austin Powers shots I decided to look at the settings and found they were at 1080i (the mkv is 720p). I reset it to auto and checked again and the projector then reported 1080p.

I will check again tomorrow but I have also just downloaded the latest firmware for the A.C.Ryan so that may resolve the issue.

Strange behavior and very unexpected TBH. Anyone else seen this from the A.C.Ryan HD Mini ?

Cheers
RB
 
RimBlock said:
Correct, as is resolution.

RB
Click to expand...

Which means the cable will not directly affect either of these. So a change in colours is either a subtly bizarre defect in the cable (ie just enough to mess up a small part of the negotiation between devices, but not enough to stop it working at all), or you were hoodwinked and the one or other of the devices changed their configuration during the cable swap.

I'm strongly of the opinion that it's going to be the latter.
 
EVH said:
Use Dropbox to host the files. Free account gives you up to 2GB of storage.

You can share the links here with a password (or not) and anyone can access them, so there's no awful sign up for those who don't have it.

The files will appear as a clickable download link such as: http://dl.dropbox.com/u/3766010/article-0-03809C4A000005DC-303_468x589.jpg
Click to expand...

Thanks EVH. Will take a look when I get the chance.

Anyone got a suggestion for the test disc/frame. I have limited Bluray discs due to their price until recently over here (just under 40 quid each, DVDs are around 5 quid and VCDs are around 2 quid apart from the most recent releases or imports). If it is something I may like then I will go and buy it (if I can).

RB
 
Demon said:
I believe your camera's dynamic range isn't sufficient to capture both dark and white levels of a video image, but you could take two shots, one over exposed, one underexposed to catch both ends..
Click to expand...

Searching around it seems like there is no comparison I can find that compares the dynamic range output ability of the Epson projector (although I would have thought this would also have been affected in part by the screen) and the cameras ability to capture the same dynamic range. DPReview has a dynamic range test in the review they did of the 5D here but they used their own scale :(. i would propose to calibrate the projector and then take a shot of the calibration image in order to assess how close it can get and then decide on the best way forwards. Sound reasonable ?

RB
 
I went to the shop and picked up a couple of cables and an Avia Home Theatre calibration DVD (all on loan).

The first being an 8 meter no-name Taiwan made cable and the other being a 10 meter branded (don't recognise the brand, "click" something IIRC). Both cables are boxed as new and taken from piles of stock so not obviously hidden away for a special purpose. I will take pictures and put them up so people can see the boxes and the cables and do their own searching about if they wish. I have no idea of the cable prices either as the shop didn't say. I will ask when I return them but not before as it is not so relevant and helps to, at least in part, give some distance from the price issue.

I ran through the Avia calibration last night including using the three coloured cells and found that the 'Theatre Black 1' set-up was pretty much spot on for basic calibration after turning the colour temp down to 6500.

I bought some more Bluray discs yesterday and I will probably use a couple of images. One 'for the boys' and one with more complexity.

Realistically I will not be taking any pictures until the weekend. I still need to get the PS3 from my brother-in-law. I also don't know how long they are willing to let me borrow the cables for. I am hoping that they will allow until the beginning of March as I will get my new Yamaha 767 Amp then and so could do a second set to see if there is any noticeable difference between passing through the Yamaha 465 and the Yamaha 767. Hmm, passing direct, passing through the 465 and passing through a 767..... 3 sets maybe. I will see how long one set takes and will do this if I can.

I would propose to put the shots up along with links to the cr2 raw files with just labels (i.e. cable 1, cable 2, cable3). I will also make available a spreadsheet with a password which contains the information about which cable matches which set of pictures. I will then post out the spreadsheet password a week later so people can discuss without knowledge of the cables but the links between cable and pictures are set for people to download so they can not be doctored based on the discussion (helps to maintain a little integrity).

EVH, were you going to do some as well. I remember you mentioned you could but didn't confirm if you would :D.

Thanks
RB
 
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