This page is a wiki. Please login or create an account to begin editing.


45 posts / 0 new
Last post
Protocol 7's picture
Offline
Joined: 2010 Aug 7
How to make a PROPER copy of a CD for sharing here (or anywhere else).

Unlike other systems, Mac OS doesn't treat CD images as read-only. A HFS or HFS+ volume is treated the same whether it's on a floppy, hard disk, CD, zip etc. Unless the media is write-protected, it's fair game for writing to. And Mac OS (especially OS X) loves writing things to volumes.

From a software preservation point-of-view this is a nightmare and it's sadly all too common to find valuable CDs imaged incorrectly. Yes it all might sound a bit anal, but really if it's not hard to do it right, why do it wrong?

So here's a couple of quick pointers on how to image a CD correctly and not mess it up afterwards. The key to this last part is to ensure than the image file is read-only before attempting to mount it. This has all been covered before in different parts of the forum but it may be buried too deep for some to find.

OS X

To image a CD in OS X you just need the built-in Disk Utility. This will also handle Mac/PC "hybrid" discs (but not CDs with audio).

Pop in your CD and launch Disk Utility. Click on your CD/DVD drive (not the volume) in the drive list (Fig.1) and then click on the "New Image" button on the toolbar. Set the output type to "DVD/CD Master" with no encryption and save it out (Fig.2).

Once the image is created, right-click on the image (or click and go to the File menu in the Finder), choose "Get Info" and tick the "Locked" option (Fig.3). Now the image is read-only and won't be modified if mounted (Fig.4).

A DVD/CD Master .cdr file is just a plain flat disc image, so you can change the file extension to .iso if you like.

Mac OS

Toast is the weapon of choice for imaging CDs in the classic Mac OS. You will need at least version 5 if you wish to image Mac/PC hybrid discs (but not CDs with audio).

Pop in the CD and run Toast. Click on the Copy button (Fig.5). From the File menu choose "Save as Disc Image" (Fig.6) pick your destination and filename and click Save (Fig.7).

Once completed, right-click on the toast image (or click and go to the File menu in the Finder) and choose "Get Info" and then "General Information" from the options (Fig.8 ). In the Info dialog box, tick the "Locked" option (Fig.9). Now the image can be safely mounted without being modified by Mac OS (Fig.10). If the disc was a hybrid, Toast will mount both "sessions" on the image as seen here (Fig.11).

Windows / Linux etc

Pretty much any CD tool on these platforms will be able to successfully image a Mac CD. Just because Windows can't mount a Mac volume (without third-party software) doesn't mean it can't be copied. ImgBurn, Alcohol, UltraISO, Nero, etc.; can all make a proper ISO image of a Mac CD.

On Linux the situation should be the same (you could even do a device copy using dd from the terminal).

As a precaution it's good to make the iso image read-only before compressing it to share. In some cases it will remain read-only when extracted on a Mac and thus will not be modified if mounted. Though it's good practice to always check if an image is locked before mounting.

CD Audio

To get a proper 1:1 copy of a CD with audio tracks you need to use a tool that can create multisession images. In OS X 10.4+ you can use SimplyBurns or FireStarter FX. For older versions of OS X there's MissingMediaBurner. These tools will create a bin/toc image (the bin file contains the raw data and the toc file contains the necessary track info). It's the Linux equivalent to the more widespread bin/cue format that's commonly used in Windows. There are no tools to create these in the classic Mac OS.

For Windows you can use a tool such as ImgBurn, Alcohol or UltraISO for bin/cue, or burnatonce for bin/toc. In Linux any tool that's based on the cdrdao engine will output a valid bin/toc file that can be burned on OS X by SimplyBurns, FireStarter FX or MissingMediaBurner. For more info check out the discussion here.

Comments

Thundersock's picture
Offline
Joined: 2010 May 20

This is incredible, nicely done. It looks like "Figure 8" was changed to a smiley.

About locking and modifying:
You lock the image after it's created? What would that protect against? Couldn't you do that yourself after download if its important?

Protocol 7's picture
Offline
Joined: 2010 Aug 7

Yep. Locking it is to prevent the image from being modified by the OS when it's mounted. There are plenty of images out there that have been modified because they were mounted while still writable. And yes you can also do it with an image you have downloaded. Unless you have a reason not to, you should always do it with any disk images.

24bit's picture
Online
Joined: 2010 Nov 19

Very comprehensive manual indeed. What about us regular folks running SheepShaver on a low end X86 host? Smile

Protocol 7's picture
Offline
Joined: 2010 Aug 7

Thanks!

You can just use a tool native to the host OS. There's tons that can make a plain iso image from a CD. The main reason I wanted to put this together was to try to cut down on "bad" CD images coming from the Mac side.

Thundersock's picture
Offline
Joined: 2010 May 20

Oh, I think I get it now: You lock the disk image because the IMAGE gets modified when you mount it as a disk, which messes it up the next time anyone mounts it.

Protocol 7's picture
Offline
Joined: 2010 Aug 7

Yep that's it Smile

IIGS_User's picture
Offline
Joined: 2009 Apr 8

Great hints, thank you very much! Smile

Mk.558's picture
Offline
Joined: 2012 Apr 1

Ugh, in 10.4.11 I have to click "Session 1" to create a CD/DVD master. Selecting the drive itself (disk1) won't work, so disk1s1 does fine.

Technically, Disk Utility is just a front end for select Terminal stuff...like $ dd... and $ unmount...so it may be appropiate to cover all bases with your writeup on how to do it in Terminal (especially if someone is doing a lot of them, but then other software usually steps in at that point). If you were doing it in batch Terminal mode, you could just press the up arrow, edit the of= name and press Enter.

Wash, lather, rinse and repeat.

Protocol 7's picture
Offline
Joined: 2010 Aug 7

It's mostly just a guideline. If you look at the screenshot when I saved out the drive the filename was Session 1, so it defaults down to that anyway. The main thing it to image "all" of the disc.

There's many different ways to do it, I just went through a couple. I still do all my imaging on Windows (with ImgBurn usually) as that's my daily driver.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

@Protocol 7: I've made this topic a "sticky" (don't know why it wasn't before now).

Unfortunately imageshack is no good as a click-to-view depository any more. Would you be able to create a new "app" page, add the pics, labeled Fig 1, Fig 2, Fig 3, etc, into a zipped archive and up them to the new page? - I'll get them inline into the topic's body in a permanent position and local to the MG (I'll deal with the "app" page afterwards).

Protocol 7's picture
Offline
Joined: 2010 Aug 7

Thanks MTT!

It's been so long now that I don't even have most of those apps running anymore. Not sure if the pics are really needed as I hope I explained everything clearly enough. I'll see about creating new ones but it might be a while.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

Ha, I see. It was a while since you created this topic. Wink

If those original pics are unavailable to you, then it would be much easier to remove broken links than having to re-install software just to recreate them.

As you say, your explanations are clearly outlined...

Although, if at anytime you'd like to see some pics inline to the topic, the offer still stands.

Much appreciated, thanks.

mrdav's picture
Offline
Joined: 2011 Dec 3

@MikeTomTom. With reference to your edits on how to deal with CDs with audio, I use UltraISO for making a bin/cue. The full version is not free like ImgBurn, but neither is Alcohol

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

Hi mrdav, I'd known UltraISO was a good tool for this. I was just removing/updating some dead links to what was already here... I have added a page link for it above, tho'.

Next, I'll work on some of those dead "Fig.n" links .. to remove or revive... Wink

mrdav's picture
Offline
Joined: 2011 Dec 3

Thanks, Mike. Smile

Protocol 7's picture
Offline
Joined: 2010 Aug 7

The free edition of Alcohol (52%) should be fine for creating images. I haven't used it since moving to ImgBurn but I don't think it lacked anything in the image making department. It just wasn't able to burn like the paid version.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

I was going to link to the free version up in the page, but decided against it because of spyware concerns. Not that ImgBurn is pure either, but it's easily installed without. The free version of Alcohol has these limitations over the paid version:

Alcohol 120% Free Edition lets you use up to 2 virtual drives, instead of 31 in our retail version, and can write to only 1 drive simultaneously instead of unlimited with our full version.
There are no copy protection emulation options.

Included in the free Version is Smart File Advisor that helps to keep your system up to date by notifying you of the latest Software Updates as soon as they become available.

While I was searching for updated links for the page above - I stumbled upon what may possibly be an ImgBurn Killer - called "AnyBurn" (check the Tutorials link on that page).

Besides being able to burn/image CD/DVD/BluRay, it can run on any Windows OS from 2k and above, comes in 32 & 64 bit flavors, has install or portable versions and is 100% freeware with no additional gotcha's or payloads; it also has these interesting features:

Create and convert disc images files... including .DMG (for direct editing, burning or converting to .iso)
Create bootable usb drives

I haven't had much time to test this app as yet, but I went so far as loading up the Leopard DL-DVD .DMG for editing - and yes, it can see every file and directory on the .dmg

So I think (hope) there may be a future for this one in our arsenal of imaging tools.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

I stumbled upon what may possibly be an ImgBurn Killer - called "AnyBurn"

Perhaps not...
With AnyBurn I burned an iso called "Dev-CD-Jan94.iso" to CD ROM
MD5 ckecksum: 851b7a57554c80a33c1055b324c55d8b *Dev-CD-Jan94.iso

Again with AnyBurn I created a new .iso from the burned CD
MD5 ckecksum: e43cd91d57fcf64c0512aebf7ac88c98 *Dev-CD-Jan94.iso

Not what I was expecting/hoping to see... the new iso mounts OK and all content looks the same, with same date stamps, etc, but there is a file size difference between the two iso's, hence different checksums.

butterburger's picture
Offline
Joined: 2014 Aug 16

MikeTomTom, please cksum those files.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

I conducted the same test using ImgBurn, using same device, .iso file, media.

With ImgBurn I burned the .iso "Dev-CD-Jan94.iso" to CD ROM
MD5 ckecksum: 851b7a57554c80a33c1055b324c55d8b *Dev-CD-Jan94.iso

I then copied the new CD ROM back to .iso using ImgBurn
Result:
MD5 ckecksum: 851b7a57554c80a33c1055b324c55d8b *Dev-CD-Jan94.iso

Which is what I would expect to see; no difference.

fogWraith's picture
Offline
Joined: 2009 Oct 23

I'd like to nominate toast for OS X as well, it seems to do a much better job when handling hybrid discs... but it could also be my imagination Tongue

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

I think Toast is OK for hybrids, but it's bin/cue for Mac HFS/mixed audio that's been the big problem with Mac's in general. Toast I think can burn bin/cue OK but it's creating them from original media that's been the main issue. - could also be my imagination Wink

mrdav's picture
Offline
Joined: 2011 Dec 3

-->could also be my imagination<---

No, not your imagination.

IIGS_User's picture
Offline
Joined: 2009 Apr 8

So, real? Wink

IIGS_User's picture
Offline
Joined: 2009 Apr 8

Unfortunately, the future of the Toast application is uncertain to me.

I still use Toast 10, the latest version that can burn newly created HFS Standard media,
and I hope it still works with my new Mac which requires 10.12 minimum.

Let's see when I need to use it then. Wink

Toast 10 is a 32 bit application that no longer will work with upcoming macOS versions,
as they can run 64 bit applications only, as it has already been announced.

Parts of Toast are in AppStore now, but I don't trust them.

fogWraith's picture
Offline
Joined: 2009 Oct 23

Toast 10 is also my go-to application for creating images that are either pure Mac or hybrid discs, so far it's been working great... and the complimentary disc catalog application makes it only better when processing tons of discs Wink

The less problems the better...

SkyCapt's picture
Offline
Joined: 2017 Jan 11

"... upcoming macOS versions ... run 64-bit applications only .. it has already been announced."

10.13 - won't be apple's lucky number, nor ours.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

Pop in your CD and launch Disk Utility. Click on your CD/DVD drive (not the volume) in the drive list (Fig.1) and then click on the "New Image" button on the toolbar. Set the output type to "DVD/CD Master" with no encryption and save it out (Fig.2).

Have these options changed in later (or earlier) versions of Disk Utility than what was used here?

I'm using Disk Utility in Leopard (the only Mac OS X I have access to, currently) and I don't see any of the above options to set the output type to "DVD/CD Master" after clicking the "New Image" button.

MacTouch's picture
Offline
Joined: 2016 Mar 19

Hi Mike,

When I have selected the volume to create an image & clicked to this button, I have this window :

If I click on the image format pop-up menu here, I have the DVD/CD Master option available...

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

Hi MacTouch. Thanks for the post and the pic. That really helps.

What I'm referring to or should really have mentioned - is imaging a hybrid Mac/Win disc. In order to do this, following the instructions in the "how to" of this topic, you must select the device name and not the mounted disc name. Also, in selecting the device name, even on a single partition disc ensures a byte for byte imaged copy.

If the disc was a hybrid, selecting the name of the mounted disc as you have done in the pic, would create an image of the mounted Mac part only.

Anyway, it looks as though Apple has dropped this feature from Leopard on.

The instructions using the method in the topic description above appear not to exist in the utility after 10.4.11, so it may need to be revised. - unless I'm missing something?

MacTouch's picture
Offline
Joined: 2016 Mar 19

Ok. So,

This will also handle Mac/PC "hybrid" discs

cannot be applied here with Disk Utility, but only with normal discs, I presume...

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

No, it looks maybe its possible and perhaps I was missing something after all.

In Leopard+ If the image is a hybrid, then select only the unmounted hybrid part and burn that to CD/DVD Master. Sounds weird but it makes an image of the hybrid. - using Toast to mount the resulting .cdr, both parts mount with file-names and time/date stamps intact.

I have yet to test checksums against this image with images I've created elsewhere, but it looks promising.

Tho' frankly, its probably just as easy to use Toast up to version 10.

Anyway, thanks for that pic, it gave me the clue I needed.

MacTouch's picture
Offline
Joined: 2016 Mar 19

YW. If I can help again, just tell me. I look forward to know what's the result. Wink

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

The results I am not happy with.

Test .iso used was small hybrid image inside zip file located here named "fmproca3.zip" (16.21 MB), 2nd DL in page.

Unzipped it has the MD5 and filename:
d95dbb073ed8dc1267c6bba43bc3439e *FMPROCA3.ISO

Tested by burning the iso to CD using ImgBurn and then also with ImgBurn, back to .ISO again.
Results as expected/desired, the fresh iso is identical to the unzipped original:
d95dbb073ed8dc1267c6bba43bc3439e *FMPROCA3.ISO

Took CD to Mac running Leopard.
Created toast image. Result is different to above.
Created .cdr using the Utility. Result also not the same.
In-fact both Toast and the Utility app created completely different disk images, including file-size, different from each other and the original.

My conclusion is that both Toast and the Utility do not create byte for byte copies of an original CD.

I would like to test the Utility app under 10.4.11 or earlier, using the steps mentioned in the topic above, but don't have access to that OS at the moment.

I also suppose that other disk imaging tools mentioned in the topic should undergo similar tests.

24bit's picture
Online
Joined: 2010 Nov 19

I still have 10.4 in VMWare on my Snow Leo installation.
I could give it a go, if nobody else chimes in. My guess is that if Leopard does not do it right, Tiger will not either.
Maybe we could set up a small Windows 2000 instance with IMGBurn and some other needful things for Virtual Box? People could DL Virtual Box for their OS and add the pre-built instance.
I´m unsure to offer a MS OS here though, even as W2k is outdated by decades.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

Hi 24bit, I have uploaded what appears to be a good solution to creating byte for byte copies in Leopard and newer, called "LiquidCD" Had this sitting for ages in my back-up of "things to look at later" bin. Out of desperation I got around to it yesterday. And what a pleasant surprise it was too.

I performed the same test as I did with ImgBurn - used the FMPROCA3.ISO from here, used LiquidCD to burn it to CD, then used LiquidCD again to image the new CD to ISO. The results were identical to the ImgBurn test - No difference at all. Excellent.

LiquidCD copy CD to ISO results
MD5 checksums of FMPROCA3.ISO and ISO copies made by LiquidCD
- OS X 10.5x

I don't know if the earlier (Tiger) version of LiquidCD will be as good as this, as I can't test it either.
When I get back home (in a week or so, yet), I will get around to testing Disk Utility in 10.4 as I think that Apple in 10.5x, dropped the feature that LiquidCD uses (copy the device data content, not what mounts) making it impossible to get accurate copies. But if you're able to test also, please do.

What I find really disturbing is that the multitude of Toast images that we have here may not be accurate imaged copies of original media.

24bit's picture
Online
Joined: 2010 Nov 19

As you are mentioning it Mike, I have a copy of LiquidCD sitting around on my 10.6 system as well.
I seem to recall using it with my first Hackintosh and a pATA burner. I did not use it much with the newer sATA-only rig.
Sad to see so many titles not being archived as a 1:1 copy, but little we can do about it, presumably.
Thanks for the operose task figuring thinks out!

SkyCapt's picture
Offline
Joined: 2017 Jan 11

"Toast images may not be accurate imaged copies of original media..."

It became obvious to me when a Toast scan+burn of any one-partition PlayStation1 game doesn't function (however runs with a 'mod chip' patched version of the PS1).

I suspect even a 1:1 byte copy of a disc can fail ! due to strict anti piracy, if the program were to sense the read speed of the disc and find it to be different than the expected read speed of their manufactured discs. There are Lots of mean tricks that anti piracy might employ...

mrdav's picture
Offline
Joined: 2011 Dec 3

MIke, the box to write in is getting so narrow that I am continuing this thread afresh in a lovely wide box.

I suspect the problem of md5 from the Toast image-->burn-->image process is to do with the way Toast reads the CD. I don't know much about this but I found the following comment in here under the heading "How can I verify the downloaded ISO images and written optical media?":

"The problem with the verification of written optical media is that some media types will possibly return more bytes than those found in the ISO image. This trailing garbage is impossible to avoid with CD written in TAO mode, incrementally recorded DVD-R[W], formatted DVD-RW, DVD+RW, BD-RE, and also with USB keys. Therefore, we need to read exactly the same number of sectors of data from the media as are found in the ISO image itself; reading any more bytes from the media will alter the checksum result."

My searching around (see here) indicates that Toast deals with a CD in TAO mode (Track-at-Once) where the tracks are consecutive sets of sectors that subdivide the CD content. Consequently, if the actual data ends part way through a track, some garbage data will be read/written from/to disc. You can find more information on various modes such as TAO here.

So, in summary, I expect that the real data is preserved properly by Toast and that the different md5 values is due to random garbage between the end of the real data and the end of the last track read. One way to check this is to calculate the md5 in a similar way to that described in the first link above. (I have not done this yet...have to find "isosize")

That is my understanding (all based on what I have read in the above links).

butterburger's picture
Offline
Joined: 2014 Aug 16

trailing garbage

As far as I am concerned, this is common knowledge. I advocate to use cksum.

mrdav's picture
Offline
Joined: 2011 Dec 3

Well, I have made some progress. "isosize" is part of the util-linux package. From this, I compiled "isosize" on Mac OS X 10.6.8 and ran it with option -x and argument being the path to FMPROCA3.ISO. This returned sector count of 4892 and sector size of 2048. I can email you a copy of "isosize" if you like.

I then burned two CDs from FMPROCA3.ISO, one using Toast 7 and the other using LiquidCD. For each CD I did the following:

1) Mount CD
2) run the command df in the terminal and note the device name for the mounted CD
3) unmount the CD volume (I used Disk Utility)
4) In the terminal, execute the following:

dd if=device_name_we_noted_before count=4892 bs=2048 | md5

This will read the correct number of bytes from the CD for FMPROCA3.ISO and pipe it to md5

I found that both CDs returned the same md5 value but surprisingly that value was different from the md5 of FMPROCA3.ISO. Presumably the ISO file has certain information in it that is not part of the data that is destined for the CD, and that the extra information in the ISO file depends on the application that creates it.

Since both Toast 7 and LiquidCD both produce identical CDs, as determined by the md5 of the CD, from the same ISO file, and because you have concluded that LiquidCD makes reliable copies of the CD, I conclude that Toast 7 also makes reliable copies (in the sense that burning a CD will give a correct copy)

This probably needs more testing. For example, what happens if we burn a CD with Toast, then make a new image using Toast and then burn it back to another CD? Is the md5 of the first CD the same as the second CD? Similar testing can be done with other software.

MikeTomTom's picture
Offline
Joined: 2009 Dec 7

Some very interesting findings, mrdav. Thanks for looking into this. I'm currently in NZ and don't have access to my usual array of tools. I have a notebook running a Windows OS and have access to a G4 Mac that can dual boot to 9.2.2 and OS 10.5x but that's it. The Mac has Toast version 6 and it doesn't create identical copies, AFAICT. I would like a copy of your "isosize" but likely it won't see any use for at least another 3 weeks... unless it can run on the G4, too...

ImgBurn also does sector count and size checks before it burns to disc or writes to image, and creates a log file for each burn/write.

Excerpts of what it logged when burning FMPROCA3.ISO to CD:

Source File: D:\Downloads\m-garden-testbox\CD-ISO-test\FMPROCA3.ISO
Source File Sectors: 13,540 (MODE1/2048)
Source File Size: 27,729,920 bytes
Source File Volume Identifier: FMPROCA3
Source File Application Identifier: TOAST ISO 9660 BUILDER COPYRIGHT (C) 1993-1995 MILES SOFTWARE ENGINEERING - HAVE A NICE DAY
Source File File System(s): ISO9660
Destination Device: [0:0:0] PIONEER DVD-RW DVRKD08A 1.51 (G:) (USB)
Destination Media Type: CD-R (Disc ID: 97m26s66f) (Speeds: 4x, 10x, 16x, 20x, 24x)
Destination Media Sectors: 359,844
Write Mode: CD
Write Type: SAO
Write Speed: 10x
Test Mode: No
OPC: No
BURN-Proof: Enabled
Filling Buffer... (40 MB)
Writing LeadIn...
Writing Session 1 of 1... (1 Track, LBA: 0 - 13539)
Writing Track 1 of 1... (MODE1/2048, LBA: 0 - 13539)
Synchronising Cache...
Image MD5: d95dbb073ed8dc1267c6bba43bc3439e

And what it logged when writing the new CD back to ISO again:

Source Device: [0:0:0] PIONEER DVD-RW DVRKD08A 1.51 (G:) (USB)
Source Media Type: CD-ROM
Source Media Sectors: 13,540
Source Media Size: 27,729,920 bytes
Source Media Volume Identifier: FMPROCA3
Source Media Application Identifier: TOAST ISO 9660 BUILDER COPYRIGHT (C) 1993-1995 MILES SOFTWARE ENGINEERING - HAVE A NICE DAY
Source Media File System(s): ISO9660
Read Speed (Data/Audio): MAX / 8x
Destination File: D:\Downloads\m-garden-testbox\CD-ISO-test\CD-ISO\FMPROCA3.ISO
Destination Free Space: 26,291,073,024 bytes (25,674,876 KB) (25,073 MB) (24 GB)
Destination File System: NTFS
File Splitting: Auto
Reading Session 1 of 1... (1 Track, LBA: 0 - 13539)
Reading Track 1 of 1... (MODE1/2048, LBA: 0 - 13539)
Image MD5: d95dbb073ed8dc1267c6bba43bc3439e

The sector sizes appear different than what isosize returned in your tests. Did isosize only count the sectors of the Mac or Win part? - ImgBurn's MD5's match tho'. Interestingly the original software that created FMPROCA3 was Toast, circa 1995.

what happens if we burn a CD with Toast, then make a new image using Toast and then burn it back to another CD? Is the md5 of the first CD the same as the second CD? Similar testing can be done with other software.

This will be a good thing to try. I wonder if a CD-RW will be useful or return weird results, these tests could otherwise become costly Wink

I will begin with an original CD pressing and create an iso from that. I have some hybrid driver CD's here which could be good candidates (small file size of the iso for quick tests, I'm hoping).

mrdav's picture
Offline
Joined: 2011 Dec 3

jackpot! Thanks for the ImgBurn logs, Mike

Firstly, it does seem that "isosize" does not read the size of the whole hybrid Win/Mac disc image. I suspect it just reads the Win ISO part.

So I used the sector_count = 13540 taken from your ImgBurn log when I ran the dd command on the CD. However, I was still not getting it right. Then I realised that the device name I was using was only for the Mac volume that was mounted. In my case that was /dev/disk1s1s2. But I then guessed that the s2 part of the name pertained to the Mac volume and so this device name was not for the whole CD. So I tried /dev/disk1s1 instead and bingo the md5 of the two CDs that I was testing (one made with Toast 7 and the other with LiquidCD) gave identical md5 values to the md5 value that ImgBurn reports (d95dbb073ed8dc1267c6bba43bc3439e).

To summarise, to check the md5 of CDs burned from FMPROCA3.ISO, I followed steps 1-4 in my previous post (#42) with the dd command being specifically

dd if=/dev/disk1s1 count=13540 bs=2048 | md5

and this gives

d95dbb073ed8dc1267c6bba43bc3439e

which is what we are hoping for. The device name might be different in your case.

So it seem highly likely to me that a Toast image does what it is supposed to do; namely, allow one to burn a CD on which the data is identical to the data on the original source CD. A conclusive test of this would be to start with a source CD, determine its md5, make a disc image with Toast, burn another CD and determine the md5 of that. The two md5s should be the same.

Rick Dangerous's picture
Offline
Joined: 2020 Jan 14

Possible to update images in the instructions? Looks like they are long gone. Thanks Smile