Peterff Loc: O'er The Hills and Far Away, in Themyscira.

Doesn't that depend on Angel density and the dynamic range of the pin head?

But, wait, we have been discussing pin-heads haven't we? :lol: :lol: :lol:

However, I think the original question was answered in the first few responses, and also some subsequent questions as well.

The topic title was stated as PNG but we fairly quickly came to understand that it probably was meant to be DNG.

What have we learned?

1) That the term lossless is typically used in the sense of data compression and restoration:

Lossless compression is a class of data compression algorithms that allows the original data to be perfectly reconstructed from the compressed data. http://en.wikipedia.org/wiki/Lossless_compression

Note, I understand that Wikipedia is not considered to be a definitive or unimpeachable source of information from an academic rigor point of view, but it is a reasonable resource for generally accepted information.

2) That the original question was more likely to be about Adobe DNG (Digital Negative) which is an open (but still proprietary Adobe format) that is designed and proposed to be a formal standard for camera raw data, but has not yet been accepted in the way that various JPEG standards have been.

Digital Negative (DNG) is a patented, open, non-free lossless raw image format written by Adobe used for digital photography. http://en.wikipedia.org/wiki/Digital_Negative

3) That the PNG (Portable Network Graphics) format is a more recent standard than GIF, some JPEG versions and other pixel-based image standards.

Portable Network Graphics (PNG) is a raster graphics file format that supports lossless data compression. PNG was created as an improved, non-patented replacement for Graphics Interchange Format (GIF), and is the most used lossless image compression format on the Internet. http://en.wikipedia.org/wiki/Portable_Network_Graphics

4) That whether camera raw files are considered to be image files or not is a disputed and sometimes passionately held opinion, but seems to be lacking in any definitive evidence to resolve the discussion either way. Some sources refer to raw sensor data as image data, others do not. Some insist that the sensor data must be transformed (interpreted/interpolated) to become bitmap level data before it can legitimately be called an image file. http://en.wikipedia.org/wiki/Raw_image_format

5) Although most digital photographs are stored in the widely used JPEG format at some stage of their lives, that other formats can be used (such as PNG or 8/16 bit TIFF, and that none of these formats are actually required. It is entirely possible to produce a high quality print from a camera raw file without converting/saving it to one of the standard formats such as JPEG or TIFF. For distribution, such as posting on UHH an 8 bit JPEG is a normal requirement.

6) Most importantly, that taking photographs and producing results that we are satisfied with is the ultimate goal, and the manner in which we do it is a matter of personal choice. How we define things is a matter of opinion, frequently irrelevant, unless there is a formally accepted definition by a standards body such as ISO.

Send in the Angels. Let's dance!

Rongnongno Loc: FL

No. You have been discussing WITH a pin-head.

amfoto1 Loc: San Jose, Calif. USA

This thread has gone far, far off the rails and I read as far as I could, without seeing anyone answer your question as you redefined it...

DNG is simply another form of RAW.... in theory it should give same results working with a DNG as working directly with another proprietary type of RAW file such as a Canon CR2 or Nikon NEF, etc. (In fact, some cameras save as DNG... Pentax and Leica, I think... and a few others.)

DNG has some other advantages including a somewhat smaller file size than most other RAW and ability in Lightroom to embed the data in the file that LR needs to record to a separate XMP "sidecar" file when it's used with any other type of RAW. There also is greater "backward compatibility" with older versions of LR and Photoshop, if you don't want to upgrade one of those.

HOWEVER, before going off the deep end, adopting Adobe's "standardized digital negative" DNG, and converting all your images to that format with Adobe's free DNG Converter, you should read:

[lurl]http://petapixel.com/2015/07/16/why-i-stopped-using-the-dng-file-format/[/url]

That article discusses problems using DNG with Capture One post-processing software, specifically. But the same or similar may be true of many others.

Peterff Loc: O'er The Hills and Far Away, in Themyscira.

True dat, and I haven't been discussing it with you directly, so I guess that counts you out of that description! :-D :-D :-D

OnDSnap Loc: NE New Jersey

Male or Female?

lamiaceae Loc: San Luis Obispo County, CA

Angel Unicorns.

JD750 Loc: SoCal

Back to the original question.

A raw image is analogous to unprocessed film. It's waiting to be turned into a final product. (Of course with digital it can be re-processed whereas with film to negatives is a one shot deal).

A JPEG is analogus to a polarid pic. You get a processed image but no negative.

What then is the digital equivalent of a film negative? One format could be DNG. Also perhaps .psd, or any format in which a raw image that has been processed with something like ACR, (or equivlant) and saved under another format or name.

So, if you change raw to DNG then discard the raw file you are throwing away the "unprocessed film", you do lose some data. This may or may not ever matter depending on the individual's use of the image.

If you shoot JPEG you avoid this whole mess but you have less flexibility with the end product. And you have thrown away the unprocessed film and the negative. However like it or not the JPEG format has a place in the world of photography.

lamiaceae Loc: San Luis Obispo County, CA

Yes, you were. Thank you for wasting all our times on a topic that has been discussed ad nauseam. A simple UHH Search would have yielded "War and Peace" on Raw vs. DNG. No wonder I thought PNG on here was a new question. No one remembers the letters or what the H. it means. Everyone please SLOW DOWN and proof read. And why can't we edit after an hour? I for one find errors days later. And sometimes typos make us all look like fools. To say nothing of those that really do not know what they are talking about.

lamiaceae Loc: San Luis Obispo County, CA

I like that. So perhaps this otherwise repetitive redundant post served one useful thing. An interesting (new to me anyway) analogy. Though not technically (always) correct as some Polaroid films did also produce a negative.

jeep_daddy Loc: Prescott AZ

KeyRectMadam! You R right!

JD750 Loc: SoCal

Say whhhhhhat?

R.G. Loc: Scotland

If that's the case it might be worth mentioning that DNG is classified as a type of raw file.

OnDSnap Loc: NE New Jersey

[quote=JD750]Back to the original question.


A JPEG is analogus to a polarid pic. You get a processed image but no negative.



You forgot the O in rOid... as in HemorrhOid, PolarOid...lets all sound it out...

Po·lar·oid ˈpōləˌroid/

Rongnongno Loc: FL

More like a crappy format that accepts anything, including a JPG. If you do not know what is inside a DNG, be prepared for a nasty surprise.

R.G. Loc: Scotland

You make that sound like a bad thing. That level of flexibility is bound to be useful for some people in some circumstances.

Most of the time DNG are sourced from raw files, and apparently the conversion process is genuinely lossless. Since that's the usual scenario, it would be unusual to have a degraded image converted to DNG, and even more unusual to have such a DNG without knowing that it's sourced from a degraded image. And in that situation, what would have been the alternative?

You can invent all sorts of unfavourable scenarios for any format - a low capacity hard drive or memory stick that fills up too quickly if you store TIFF files for example.