Painting the edge of a CD green

[Pepsican]

But the DVDs I do that with play in my Blu-ray player![/]

 

Hi Jud

Perhaps you can buy bulk Blue Magic Marker ink and spray it on instead? You could then convert your whole DVD collection much quicker than painstakingly applying it with a pen, and trying to get an even coating .

 

Kind Regards

Alex

 

I did this the other day. My conclusion was that blu-ray is hyped. The sound and image quality was only a tat better than DVD. I think this is all a scam to get us to upgrade and sell new machines!

[esldude]

http://www.amazon.com/Uni-posca-Paint-Marker-Pen-PC-5M15C/dp/B001ANVDMU/ref=sr_1_1?ie=UTF8&qid=1463341446&sr=8-1&keywords=paint+pens

 

This is one most similar to the CD Stoplight. The water based version.

 

If you have an arts and crafts store they likely have them in singles. The lighter green one in this pack is closer to the original. I did try these way back when and it is the same type paint etc. though not the identical shade of green. You don't want to try the oil based paint pens. You do have to be careful as the Stoplight version had a groove in the tip making it easy to stay on the edge. These don't. The medium size point is closest to the Stoplight also.

 

The CD Stoplight color was close to the first two lines of my signature text below just by coincidence.

 

Here is a pic of one treated on edge and around the center hole.

 

 

Of course I would suggest not bothering as it is a bunch of baloney even though I own one of the pens.

[esldude]

The CD and transport mechanism are bathed in the light of green LEDs, which you can see when you open the motorized door which covers the disc-playing chamber. Krell claims the presence of green light helps the laser recover the data from the CD, and improves the sound quality (footnote 1). Further, the disc-playing chamber is sealed from outside light by the motorized sliding door.

 

Krell KPS-20i CD player Page 2 | Stereophile.com

 

Be sure to read JA's footnote at the bottom of the page.

[mansr]

Of course I would suggest not bothering as it is a bunch of baloney even though I own one of the pens.

 

Oh, I know it is.

[The Computer Audiophile]

Certificate of Deposit. At least that is the CD where the green really makes a difference.

 

Too good :~)

[davide256]

Anyone remember the devices that crimped the edge? One a friend had put vertical ridges something like the rim of a quarter. Supposedly was sized so it trapped that wavelength of infra-red light used in CD lasers.

 

if you wear glasses to see, take note of the edges. The matte finish is for the same reason, eliminate prism interference.

[The Computer Audiophile]

There are also rubber rings you can put around the edges of CDs.

 

I also remember people coloring the edges of an Eminem CD to defeat DRM.

[esldude]

There are also rubber rings you can put around the edges of CDs.

 

I also remember people coloring the edges of an Eminem CD to defeat DRM.

 

Why would someone want to defeat DRM on an Eminem CD? The mind boggles.

 

Or does DRM stand for something besides Demand Real Music?

[gmgraves]

Hi,

I'm not supposed to participate to this forum anymore

 

Numerical aperture is a very important concept for the design of PUH

If you consider that CD gathers light up to 26,7°, DVD 36,9°, BR 58,2°

Knowing that n=refractive index is 1,55 for polycarbonate and the numerical aperture is NAo = no sinθo

NA= 0,45 for CD, 0,60 for DVD and 0,85 for BR.

If you understand a minimum of optics design you will find out that the green pen is just an other BS concept in the audiophile world.

 

Mansr, You are right even if you can use the same OEIC for CD and DVD you still need two wavelength laser diode.

George before starting arguing, I have a PHD in optoelectronic

 

 

I have no intention of arguing. As I said elsewhere in this thread, I'm certainly no optical expert. Obviously, you are. Only a fool argues with an expert and while I might look the fool from time to time, I'm really not one.

 

BTW, welcome back, Alfe. We've missed you (some of us anyway!).

[mansr]

I also remember people coloring the edges of an Eminem CD to defeat DRM.

 

Those CDs had a data track with a Windows autorun program that prevented ripping. Painting over that track made it unreadable, thus allowing the CD to be copied.

[sandyk]

I have no intention of arguing. As I said elsewhere in this thread, I'm certainly no optical expert. Obviously, you are. Only a fool argues with an expert and while I might look the fool from time to time, I'm really not one.

 

BTW, welcome back, Alfe. We've missed you (some of us anyway!).

 

+1

[17629]

I'm kind of surprised. Everyone here is always going on about testing and backing everything up with evidence. I do just that giving 2 video's that walk you through the process (There's plenty more if anyone care to look, but I'm pretty sure that on one here will be able to find them.), and get called a troll and whatever else. This proves my own suspicion about this web site. People here care more about being right even if they're not. Before anyone tries to challenge me on that, how many people here can't get their hands on a blank DVD, a blue marker and a Blue Ray DVD drive? Given that everyone here is into computers, I would expect everyone to have a bland DVD and a drive already. So maybe everyone doesn't have a blue marker. I know that these kind of markers are rare and costly, so if anyone wants, I send them one. Or are you guys just scared of being wrong? Because given how simple this is to try for yourself, I can't come up with any other reason that makes sense.

[sandyk]

I can't come up with any other reason that makes sense.

 

It's not practical as a long term solution. Neither would I expect readability to be as good as it was originally, or for that matter to be completely reliable right across the disc with Data storage, due to the haphazard method of the Blue marker's application.

Many people buy BluRay discs for Data storage, as a 25GB Blue Ray disc is only suitable for short home movies, and you need a 50GB disc for high quality Blue Ray movies.

[17629]

It's not practical as a long term solution. Neither would I expect readability to be as good as it was originally, or for that matter to be completely reliable right across the disc with Data storage, due to the haphazard method of the Blue marker's application.

Many people buy BluRay discs for Data storage, as a 25GB Blue Ray disc is only suitable for short home movies, and you need a 50GB disc for high quality Blue Ray movies.

 

That's not why I brought it up. If you read my first post on this topic, I was asking alfe why the color doesn’t matter with regards to the green marker, but yet it does with Blue Ray and a blue marker. He says he's an expert and was just curious. I make no apologies for asking a simple, legitimate question. The blue marker does work. Anyone can try it.

[sandyk]

The blue marker does work. Anyone can try it.

 

I would suggest that they try it with many GBs of Data and confirm the Data copying accuracy with before and after Checksums.

 

BTW, Alfe IS an expert in this area, and he also designed my LG GGW H20L Blue Ray writer.

[alfe]

That's not why I brought it up. If you read my first post on this topic, I was asking alfe why the color doesn’t matter with regards to the green marker, but yet it does with Blue Ray and a blue marker. He says he's an expert and was just curious. I make no apologies for asking a simple, legitimate question. The blue marker does work. Anyone can try it.

 

Sorry didn't realise that it was a serious question:)

The DVD substrate is 0,6 mm and bluray is 0,1mm the wavelength is related to the substrate thickness so what you read is a DVD.

And yes you can read a DVD even using a blue marker on the readable side as it's a different wavelength.

There is a patent about that and some disc released in the market years ago

 

Patent WO2004027683A2 - System for applying markings to optical media - Google Patents

http://www.singulus.de/fileadmin/media/pdf/news/news23.pdf read P6

[alfe]

Thank You George and Alex

[alfe]

@17629

 

Some more explanation about blank disc which is not really blank, there is a pre-groove spiral that the laser follows while writing: this is called absolute time in pre-groove (ATIP).

The track pitch (distance between spiral) for DVD is 0,74µ and 0,32µ for Bluray.

 

If you have more question feel free to ask.

[Don Hills]

... The blue marker does work. Anyone can try it.

 

Are you taking those videos as proof? P.T. Barnum was right.

 

Anyone can try it, but the only one who can convince you is you. You have the blue pens, and you likely have blank DVD-R discs and a Blu-ray burner. So colour one in and try to write 25 GB of files to the disc.

[Jud]

Are you taking those videos as proof? P.T. Barnum was right.

 

Anyone can try it, but the only one who can convince you is you. You have the blue pens, and you likely have blank DVD-R discs and a Blu-ray burner. So colour one in and try to write 25 GB of files to the disc.

 

I was thinking he had to be kidding, as the last video he links to is obviously a spoof, but I'm not entirely sure....

[alfe]

I was thinking he had to be kidding, as the last video he links to is obviously a spoof

 

It is a spoof.

 

There is information in the ATIP about the disc itself and this is the way the burner recognise witch type of blank disc is used.

Remind you that Cyanine and Azo dyes used for CD & DVD blank disc are blue coloured .

[james45974]

Has anyone seen the black CD's? How do those work? I have two recordings on black CD's and was wondering how they work, is there aluminum reflective layer under the black to reflect the laser?

 

Hopefully this is not too OT!

[mansr]

Has anyone seen the black CD's? How do those work? I have two recordings on black CD's and was wondering how they work, is there aluminum reflective layer under the black to reflect the laser?

 

Hopefully this is not too OT! [ATTACH=CONFIG]26313[/ATTACH]

The black plastic is transparent to infrared light, and there is a regular reflective layer underneath.

[gmgraves]

 

I did this the other day. My conclusion was that blu-ray is hyped. The sound and image quality was only a tat better than DVD. I think this is all a scam to get us to upgrade and sell new machines!

 

I saw an ad today for a Samsung 4K disk player. Only US$400! And there are a whopping 300 titles of recent, junk movies to choose from at only $25 -$30. each. Of course, I've never seen 4K, but Blu-Ray looks good enough for me. For now, I'll pass

[tranz]

 

I saw an ad today for a Samsung 4K disk player. Only US$400! And there are a whopping 300 titles of recent, junk movies to choose from at only $25 -$30. each. Of course, I've never seen 4K, but Blu-Ray looks good enough for me. For now, I'll pass

 

You might think differently after seeing an LG OLED 4K with 4K medium!