iView and lab color

[dickbos]

Photoshop files I saved in lab color are not displayed in iView (3.0.1), neither as Thumbnail nor as Media. I get a small rectangle warning saying "Invalid media data [-8969]". Can iView not display files saved in lab color? Or is there something I am overseeing in my setup? Thanks. Dick Bos

[peterkrogh]

Dick,
I don't save anything in LAB, so I don't know offhand.  Have you checked the manual or the iView Forum?
Peter

[dickbos]

Peter, thanks for a very quick respons. Yes I have and no, I didn't find an answer yet. I'll keep on searching.

btw. I find your book extremely interesting and useful! Well done! Just what I need as a base for setting up a descent cataloging system.
Dick

[johnbeardy]

I confirm this is an issue and has been logged with iView. Lab images aren't thumbnailed, and I've also an example of a Grayscale mode image that's displayed as a negative.

I'd add that I don't usually use either mode and only tried this as a test a while back. I'd never use the Lab mode for a black and white conversion, one thing people do with it, and any use in sharpening workflows is now done best with the Luminosity blending mode.

John

[Rick McCleary]

Regarding the value of LAB in a professional workflow:

This is not a "fringe" colorspace anymore.  With the publication of Margulis' LAB book, there will be more people using LAB as the core workspace for creating derivative files.  It's not for every type of image, but for some, it's quite powerful.

It would be great for iView to resolve the thumbnail issue with LAB files.

[johnbeardy]

Maybe, Rick. Not read that book yet, but I used to see people using Lab much more often than recently, and it seems to have gone to the fringe certainly since blending modes were introduced. Maybe it'll come back now.

In any case I do agree iView has to support it. Have people tried opening these Lab files in QuickTime?

[peterkrogh]

Since iView relies on Quicktime to render files, the question is whether this is a Quicktime problem, or an iView problem.  Should be easy to find out where the problem is.
Peter

[dickbos]

I tried opening some lab files in Quicktime and that does not work ("file is corrupted").

I intend to use the lab-space more in my workflow because the power is incredible, not just for sharpening. Read Dan Margulis' LAB book and you will agree! I therefore posted this issue with iView's support section. Will see and let you know.

Dick Bos

[dickbos]

Hello all,

As mentioned in the previous post, the question was put with iView support. Their answer is 'No', lab is not supported. No indication was given wheather lab will be support in future updates /upgrades.

So now you know.

Dick Bos

[peterkrogh]

Dick,
Adding image support outside of Quicktime would be a HUGE engineering task.  Maybe you could request that Apple support LAB color in Quicktime. 
I would not hold my breath.
Peter

[danaltick]

Well, I actually have Dan Margulis' book on my list of books to read.  I'm certainly not going to let this deter me.  I played around with a few of his techniques listed in Photoshop User magazine a few months back and I'm convinced you can do some pretty neat stuff with LAB.

Dan

[peterkrogh]

Dan,
I guess the question - which I don't know the answer to - is whether you need to leave the master file in LAB after you do the work, or whether you can change it back to RGB.
Peter

[danaltick]

Peter,

If I remember correctly, I believe you do have to leave it in LAB; otherwise, you will lose data in the conversion, and you will definitely lose some of your layer information.

Dan

[johnbeardy]

I have a small doubt that says QT does already support Lab and that it's a problem in the way iView addresses it. Portfolio 8 also uses QT as its rendering engine for Photoshop files and reads Lab images correctly. IIRC QT itself has two rendering engines, and it may be that iView needs to check how it calls up Lab images. While saying this, I've not been able to load Lab images in QT directly.

John