I'm glad what I wrote was helpful for your understanding. A DNG file, like a TIFF file, is a container file. The DNG specification (see http://www.adobe.com/dng if you'd like to download it for more understanding) defines a standardized file format for storing raw image data. It can also contain a lot of stuff that isn't understood by a raw converter. You could encode text files, Word files, PDFs and other ancillary information into a DNG file if you were so inclined. Simply stated, the raw converter reads what it needs to do its job, and anything else that it was written to take advantage of. If there's other stuff there, it just skips it.
When you set the output revision compatibility for exporting to DNG, Lightroom cannot know what application, or revision of a plug-in, will be used to read the DNG file. You can output for DNG compatibility with Camera Raw v4.6 compatibility but then open it with Camera Raw v6.2. So there's no sensible reason for them to display a warning dialog … the DNG portion of the file is compatible, it's the LR/Camera Raw instructions that might or might not be, based on what you do, but it has no idea that you are going to use LR or Camera Raw to read the file. Similarly, Camera Raw doesn't know what's in the file except for what it needs to read if it isn't there … and what Camera Raw needs to read was there. The additional instructions are NO-OPs to v4.x of Camera Raw. So it just passes them by: it was written before knowing what they were was defined. > (Although, I don't like the notion of synching things to the "Cloud", and > that has been a hindering factor as well. > But I admit, it might be my prejudice.) BTW, there's absolutely nothing that requires you to sync anything to the "Cloud" (whatever you mean by that) with Photoshop CC or Lightroom purchased on a subscription license. The software and your files are entirely resident on your computer and its storage devices if you do not choose to use a Cloud-based storage system. The only network interaction that the software will do if you don't use the Cloud storage is a phone-home call back to Adobe's license servers, periodically, to ensure that the subscription license is still valid and to determine whether there are any software updates that you might want to install. That has nothing to do with the Cloud, it's just a standard network-security interaction passing the usual kinds of authentication certificates and keys back and forth that any system with a networked security/license requirement has been doing for the past twenty years. Your browser probably does a couple of hundred interactions like this every day if you visit any secure site, like any payment system, bank website, Ebay, Paypal, etc. If you choose to use the Creative Cloud storage services, your data *can* be stored on a networked Cloud volume, making it convenient to get to when you're not at home and connected to your storage system. But that doesn't mean anything like "synching stuff to the Cloud", it simply means that you are using a network-accessed server as a storage repository. Syncing stuff to the Cloud is more akin to the kind of pervasive data presence that DropBox does: you set it up and it created a network-shared file space on your local storage which you've give it permission to synchronize with the DropBox servers. Every system that you've enabled with the DropBox software and signed into the account is then synchronized so that the data is duplicated and in sync everywhere, making it accessible from all the systems, all the time. > In the mean time, I am going > to use PSD format to avoid incompatibility issues. In other words, you are going to write out fully rendered RGB files in Photoshop's proprietary format when you export rather than writing out raw data with processing instructions. Depending upon what you are writing out the data for, this can be good or bad. I rarely write out DNG files from Lightroom … There's no need, I have the originals and the library (that is, the raw data and the instructions) archived and backed up all the time anyway. When I write out my image files from LR, I'm usually either outputting them for use on the web, where you need to output to JPEG, PNG or TIFF to be truly useful in reduced resolution form, or outputting them for archiving finished work, where I write them in full resolution 16bit-per-component TIFF files which nets the best, most editable, most useful archive format of the *finished* work. Any raw output is an image file that requires interpretation to express the adjustments. An RGB output (JPEG, TIFF, PNG) has the adjustments 'baked into the pixel values.' Woof. I'm in a verbose mood, I guess. ;-) Godfrey > On Dec 18, 2014, at 5:36 PM, Igor PDML-StR <[email protected]> wrote: > > > Wow! > Godfrey, that's probably the most technical description that I've > ever seen on this list (or at least outside photography per se, which by its > nature is still less technical). > > Thank you, thank you, thank you! > Not only that it helped me discerning between the two different scenarios of > what is (experientially) breaking here, but (and that is probably more > important) it also helped me understanding how a DNG file works. > This understanding will be helpful in other aspects of understanding how LR > and related programs work. > > Indeed, what you described coincides with my observations. I guess the > biggest surprise that led to the situation I described was that LR did not > warn that something might not be compatible with ACR v 4.6. (And > subsequently, ACR did not complain that there was something that it didn't > understand in the file.) > I still think this is a wrong behavior on part of Adobe's software that no > warning are issued. > Such a warning is a typical behavior that many programs implement. (Various > MS Office and Windows components do that. I believe even Photoshop and > Acrobat give a compatibility warning when you are saving to a format where > certain components are not preserved, - but maybe I am mistaken about those > two.). > > I don't need to do this operation often, and hopefully, I'll be able to get > away from CS3. (Although, I don't like the notion of synching things to the > "Cloud", and that has been a hindering factor as well. > But I admit, it might be my prejudice.) In the mean time, I am going > to use PSD format to avoid incompatibility issues. > > > Igor -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
