How to DIY test for CD-R longevity / durability / error tolerance

vbimport

#1

I have posted a thread proposing a quality cd-r media longevity test roundup at cdrlabs forum. However, some cdfreaks readers suggested that I post it here too.

cheers,
Halcyon

PS I won't answer brain dead comments :slight_smile:

__ BEGIN INCLUDE ___
This idea was brought up by Nox's excellent post about a cd-r media DIY testing.

I have decided to test the longevity, durability and resistance to error build up of the best available CD-R media (exlucing medical grade media). Nox has initially offered to help me out. We'll find out if that still stands after this message :slight_smile:

This test would need more volunteers.

The idea is to test the disc's resistance to heat, humidity and radiation (UV, infra, visible) by placing them outside in the sun for the duration of the summer.

The data contents (same on each disc, verified 1:1 before testing) would then be read and tested every second day to measure for possible build-up of read-errors (and the time required to read the disc).

The test would run as long as the last disc fails to read without errors or when the testers run out of steam. Whichever comes first. I hope to be able to run the test for at least 80-90 days.

Preliminary results of how this kind of testing can affect cd-r quality remarkably fast can be found from the address Nox gave in an earlier thread:

http://es.geocities.com/pruebacds/Cds/frcd.html

NOW, I need your help

1) Media to be tested
I need suggestions for HIGH QUALITY CDs to be tested from manufacturers brands that are not already on the list:

10 x Mitsui Gold Ultra (Mitsui)
10 x Kodak Ultima Silver+Gold 80 24x (Kodak)
10 x Philips CD-R 80 Silverspeed 32x (Ritek)
10 x Fuji CDR-74 24x (Fuji)
10 x Ricoh CD-R 80 (Ricoh)
10 x Hi-Space CarbonSound 80 min (MPO)
10 x TDK Reflex Ultra 32 X (Tayio Yuden)
10 x Verbatim DataLifePlus Super Azo 32x (Mitsubishi)

Please, no suggestions for bulk media or manufacturers alredy included above. REPEAT: no bulk media will be tested. If you want to test bulk media, run your own test :slight_smile:

I think 8 is the absolute maximum of different brands to test. More than that and it'll get really cumbersome. Five brands would be much less work, but it would leave a lot of important brands out as well.

2) Methodology to be used

Initial test procedure would be as follows. Please give comments on how to improve the test. If you can only criticise and not offer a suggestion for an improvement, I'm not interested in your comments :slight_smile:

  • X volunteers (hopefully 5) each use/test Y pieces of test media (hopefully 2) from each manufacturer (that means up to 16 disc pers volunteer!)

  • Same audio data is burned on each disc and verified to be 1:1 on each test media, before test starts

  • Image of the bit-perfect test data is written to hard-disk for comparison purposes

  • Read speed (test for 1:1 accuracy) of each disc written down before test starts (each speed measured in each volunteer's respective set up)

  • Discs are labelled clearly on the CLEAR inner ring of the disc. No stickers, no writing on the surface, no printing (we probably need to engrave codes on the ring, because felt tip pen ink might wear out during the test)

  • All the discs are placed side by side in a sunny place outside where they are exposed to temp, humidity and radiation changes daily.

  • Íf possible, one disc of each brand should be layed out label side up and another disc form the same brand label side down

  • The test discs should be on a surface that prevents them from being moved / scratched / dropped / being stepped on.

  • Rain can hit the surface of discs as far as I'm concerned (this would simulate really hard conditions / increased aging test)

  • Every second day each disc is brought in, radially wiped clean with a lint free cloth under wet conditions and then dried.

  • Each cleaned/dried disc is then tested for read errors (1:1 bit accuracy) and read speed (compared to original speed).

  • All errors and read speeds are marked down

  • When and if the read speed becomes intolerably slow with a lot of read errors or is completely unreadable, it is removed from the testing batch and the time of death is reported.

  • Each test disc that fails is photographed with a (digi)cam to illustrate the changes on the physical appearance of the disc, both on the label side and the reflective side

  • Testing continues untill all discs have failed or time available for testers runs out (this needs to be agreed upon by the testers themselves)

3) Test volunteers

I need people (I can provide the discs) that can take part in this gruelling, but a VERY useful test, for as long as 3 months.

Summer is a good time, but I don't think anybody can promise to be there for testing every second day.

Therefor I think we need five volunteers (four in addition to myself) so that we can make it less likely for all of the testers being away at the same time. At least we'll have some data every second day, if not from all volunteers.

I must warn you, this will be very cumbersome and time consuming test. I'm not even sure it's doable and that's why I'm posting this idea here and soliciting comments.

If you have any improvements to the test or want to participate in the test (volunteers from within EU preferred, can't afford to send the discs to Asia/USA), please reply to this thread.

You're an ideal candidate if you're in an office summer job for the duration of most of the summer, using a computer with a cd-rom drive in it, know how to use EAC and have a place on which to put the discs for testing.

What can I or other volunteers offer in return?

Fame and/or notoriety, that's all. No money involved I'm afraid. Not for me at least.

4) Publishing the results

The data will be gathered from all volunteers when the test ends:

  • read errors and read speed for each disc from all participants for all the dates tested

  • in addition the cd-burner model, cd-burning speed, cd-rom reader model and computer used will be catalogued

  • the results will then be tabulated and calculated for averages, medians and variances

  • some textually summary will be written to explain the test data

  • images of each disc from the day they failed will be provided

  • hopefully a winner or winners from the gruelling test will be revealed

  • results will be posted here, on most important forums and proably in a couple of computer magazines as well

  • the test data will be sent to manufacturers (or rather, an URL of the test report will be given to them via e-mail) and their possible responses perhaps included in the test addendum

FINALLY

Why am I doing this?

I'm going to start archiving some digital pictures and others stuff for archival purposes. I want these archival copies to last as long as possible, without having to transfer them to new media every year or so.

The last even semi-reliable durability test (in addition to the one Nox posted about) that I could find is from 1996.

A lot has happened on the cd-r scene since.

I just want to personally learn what is the most error resistant and durable HIGH QUALITY CD-R media right now and want to publish the results to others.

So, anybody want to volunteer? :slight_smile:

cheers,
Halcy

PS Upon reading my message through myself, I think up to 10 volunteers (1 disc / brand = 8 discs / volunteer) and testing every three days would be more realistic. I'm not sure even that's doable, but let's hear your comments first...


#2

just a tip to make it less tedious, i really dont think every 2 days is necesary, if you’re gonna do it for 10 weeks or something, once a week i think may even be enough. thats 10 data points of error amounts…