Dumping PC DD/HD Disks

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IFW
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Re: Dumping PC DD/HD Disks

Post by IFW »

No idea, as downloading bigger files will have to wait for the weekend at least, but probably yes.
Once preservation settings are enabled (-i2) all setting are correct for dumping, unless overridden by the user. Whether the dump itself is good I can't tell until this specific version of Copylock gets supported by the analyser used for generating IPF files.

Everything can be written back to disk (apart from physical damage...) so this one wouldn't be a problem either.

hydr0x
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Re: Dumping PC DD/HD Disks

Post by hydr0x »

IFW wrote:I'd definitely add guide formats to your dump commands - would save a lot of time on redumping hard to read disks ;)
Could someone please post some examples on that?
Can you elaborate on this? It's hard finding definite information on the forums regarding the guide formats. As stream dumps are not influenced by settings like encoding or sector size, I have to assume the guide format only determines three things: Min/Max Track, 40/80 Track and Single-/Double-Sided. So all this does essentially is limiting the stream recording/dumping to the relevant tracks. Is this correct? If that's the case, is it always secure to do this? I mean, can you be sure that there's really nothing in the other tracks, e.g. copy protection stuff? I wouldn't want to risk noticing that the guided dump is actually missing something a year later only to find the disk to be dead by then. Or is this technically impossible? Of course always assuming the guide format was correct in the first place, which should be pretty obvious though.

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mr.vince
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Re: Dumping PC DD/HD Disks

Post by mr.vince »

If you add a guide format, which is valid, and the read is bad, DTC will retry.

This will affect stream files as it will retry until the dump is good. Your stream file will then have at least one good revolution as well.

hydr0x
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Re: Dumping PC DD/HD Disks

Post by hydr0x »

mr.vince wrote:If you add a guide format, which is valid, and the read is bad, DTC will retry.

This will affect stream files as it will retry until the dump is good. Your stream file will then have at least one good revolution as well.
If I dump via the GUI and select multiple profiles, e.g. a MFM profile and stream preservation, does it not retry too? I have no problem switching to guide format as it saves me time, but I want to be absolutely sure I don't miss something that way.

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mr.vince
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Re: Dumping PC DD/HD Disks

Post by mr.vince »

That is what we meant. Using stream and at least one other format.

hydr0x
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Re: Dumping PC DD/HD Disks

Post by hydr0x »

mr.vince wrote:That is what we meant. Using stream and at least one other format.
Mh? I though selecting non-guided (aka preservation) stream profile + another profile is not the same as selecting guided format stream profile + guide profile. In one case it'll dump all tracks into stream files, in the other it only dumps the relevant tracks into stream files. What I want to make sure is that the latter is always safe, that I can be sure the non-dumped tracks won't ever be needed.

So far the only advantage I see for the guided format is time saving as it usually only reads half as many tracks, right? I can't see the retry advantage you mentioned as both methods outlined above retry, don't they?

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mr.vince
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Re: Dumping PC DD/HD Disks

Post by mr.vince »

Retry per definition only does five retries. You might want to set more for very old or worn disks.

hydr0x
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Re: Dumping PC DD/HD Disks

Post by hydr0x »

mr.vince wrote:Retry per definition only does five retries. You might want to set more for very old or worn disks.
That's not what I asked :(

I want to know what the advantages/disadvantages are when comparing these two methods when working in the GUI:

Method 1) Multiple: "KryoFlux stream files, format guided" + some guide format (e.g. MFM sector image)

Method 2) Multiple: "KryoFlux stream files, preservation" + some format (e.g. MFM sector image)

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mr.vince
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Re: Dumping PC DD/HD Disks

Post by mr.vince »

Preservation always keeps e.g. five revolutions, all tracks (even when guide only needs 40 of 80) but is also affected by guide format.

Chose preservation when you want to preserve, the other one is when you just want to keep what's relevant for the guide format.

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IFW
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Re: Dumping PC DD/HD Disks

Post by IFW »

Please read the new description of stream file usage in the complete manual supplied with the latest installation package; it explains what mr.vince said in more details.
It is important to note, that this description is only true beginning with that software release; the previous behaviour was very different.

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