TIF save options query

[Swatcher]

Hi all,

I am running v3.5.3 (Final Release build 3.53.3690.27077), downloaded in the last day or two. I'm not sure if this is related to a problem I have just discovered with TIF files.

I have scanned several old prints using HP scanning software and saved them as TIF, which I then trim and clean with PDN. Up till now that's all I've done with them, beyond a bulk conversion to jpeg using IrfanView, and all has been well.

Now, I have decided to edit and export the TIFs with my Canon camera software (DPP). TIFs that I have previously editied with PDN show up fine in DPP and I can export them quite happily. However, possibly since the upgrade but that may be coincidence, TIFs edited in PDN are no longer showing up in DPP - at least, the file is showing but not the thumbnail and consequently I can't edit it.

I suspect it may be caused by the LZW compression that PDN is applying to the saved TIF. I could have sworn that there was an option for turning this off in previous versions but I can't even find a preferences dialog. Do I need (new) glasses?

Regards,

Swatcher

[Sozo]

As far as I can tell, Canon's DPP program does indeed not support LZW compression. Also, I can't see any way to turn it off in Paint.NET. Would saving in PNG work?

EDIT: Ah, try updating DPP to 3.2, that should fix it.

[Swatcher]

Thanks for your suggestion, CommanderSozo. I was already on DPP 3.6 but have now upgraded to 3.7 anyway but to no avail, I'm afraid. Glad to hear I don't need glasses. The only uncompressed format DPP reads is TIF so PNG won't do, except as an intermediate save before converting with something else, which is what I have been doing with BMPs.

Can anyone from the s/w team confirm that you can't turn off LZW compression when saving TIFs?

Regards,

Swatcher

[Sozo]

Lol, the articles I was reading said that the LZW compression issue had been resolved by 3.2, I didn't even know it had been updated further. Sorry that didn't help. Look here, towards the bottom of the page, just to show you I'm not crazy.

[Swatcher]

Nope, you're not crazy but I'm not surprised, having used their s/w for some time. Maybe it's the level of compression it can't read. I might try and point this out to Canon but this may try my patience too much again.

How do you find out what level of LZW compression is being applied?

Cheers,

Swatcher

[Rick Brewster]

Honestly, you shouldn't ever use TIFF if you can avoid it. It is provided in Paint.NET only as a best-faith convenience feature.

[Swatcher]

Really?! I'd love to know why. I only use it because it was a way of storing uncompressed images which could be read by my camera's software (DPP). I'm open to suggestions...

Thanks for getting in touch.

Regards,

Swatcher

[Rick Brewster]

TIFF isn't really meant for photographs. It's an old file format that is really only used for multipage faxes nowadays. PNG is superior in every way.

Also, please don't confuse lossless and lossy compression.

TIFF can store uncompressed, or with lossless compression (e.g., LZW).

PNG can store with lossless compression.

JPEG uses lossy compression. Fidelity and quality are compromised for the sake of storage size (and thus download/upload time).

There is no reason to choose uncompressed when you have lossless compression available to you (e.g. PNG).

[Swatcher]

Thanks, Rick, useful advice. Maybe Canon should read it too! Swatcher

[MarkSullivan]

I really wish you would support non-LZW TIFFs. This (and I think lack of support for Grayscale TIFs?) is the reason I am having to move away from Paint.NET. TIFFs are alive and well in the archival community. I literally spent two months looking at, understanding, and encorporating Paint.NET into some free software I was working on... only to find that it lacked in both these areas.

You may think PNG is superior, but I would suggest supporting non-LZW TIFFs.

And even though a file format is considered lossless, there is still a reason to stick with a basic bitmap, uncompressed format. If a gamma ray comes through and zaps one bit of a bitmap, one pixel's color will be altered. If the same gamma ray hits a losslessly compressed image, it can cause a domino effect which will render the image corrupt.

[Rick Brewster]

I literally spent two months looking at, understanding, and encorporating Paint.NET into some free software I was working on...

Paint.NET is not licensed for inclusion with other software (always read the license!) so this wouldn't have been a valid path anyway.

[Sozo]

If a gamma ray comes through and zaps one bit of a bitmap, one pixel's color will be altered. If the same gamma ray hits a losslessly compressed image, it can cause a domino effect which will render the image corrupt.

I try to avoid working in nuclear fallout, personally.

[Rick Brewster]

I try to avoid working in nuclear fallout, personally.

Pretty soon you won't have a choice.

http://en.wikipedia.org/wiki/Solar_maximum

The next solar maximum is currently predicted to occur in May 2013...

But it's not news: it's a ~12 year cycle.

Substitute "gamma ray" for "cosmic ray". We often use these to illustrate the point that any software you write, no matter how safeguarded by logical, proven-beyond-doubt correctness, can still fail.

[Sozo]

Substitute "gamma ray" for "cosmic ray". We often use these to illustrate the point that any software you write, no matter how safeguarded by logical, proven-beyond-doubt correctness, can still fail.

So that was kind of like programming terminology for the worst case scenario, I see. I suppose cosmic rays are as good as any scapegoat. They do mess up Toyota's too, after all.

Regarding the "superiority" of PNG's: I don't think they're necessarily better that TIFF's, but it's a widespread standard, it is fairly compact, it supports transparency, and it's pretty high quality. I can't say a whole lot about TIFF's, but I think PNG's are the more convenient option.