Luminous Landscape Forum

Raw & Post Processing, Printing => Adobe Lightroom Q&A => Topic started by: ErikKaffehr on September 02, 2012, 02:49:58 am

Title: Some RX 100 samples processed in LR4.2 RC
Post by: ErikKaffehr on September 02, 2012, 02:49:58 am
Hi,

Here are a pair of images, shot as RAW+JPEG from my RX100. One is out of the camera JPEG the other quite heavily processed in LR4.2. All files are available here:

http://echophoto.dnsalias.net/ekr/images/RX100/Samples/index.html

The in camera JPEG also allows for significant processing. A sample is supplied with the in camera JPEG with similar processing as on RAW.


Best regards
Erik
Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: maxgruzen on September 04, 2012, 04:18:56 pm
Eric I have been doing the same with my RX 100, but find that my JPEG files degrade after some editing in Lightroom. I have used JPEGS a few times to shoot with the camera HDR and love the results, but lose quality after Lightroom processing. I have been thinking of saving the JPEG to a
TIFF or DNG and working on that??

Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: Slobodan Blagojevic on September 04, 2012, 04:26:04 pm
Preventing JPEG degradation during editing is supposed to be one of the main advantages of parametric processing. Thus I am confused that you are able to detect it?
Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: maxgruzen on September 04, 2012, 09:56:43 pm
Sloboan, What your saying is that Lightroom should not degrade JPEG files? I didn't see any degradation until I started adjusting sharpening. Perhaps what I'm seeing is normal noise increase by sharpening an 800 ISO file, but it sure seems like a lot more then that.
Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: maxgruzen on September 04, 2012, 10:10:36 pm
Well, having done a little homework on the matter I see that Lightroom is non-destrutive with JPEGS. Only on export does some degradation take place. 
Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: Slobodan Blagojevic on September 04, 2012, 11:23:30 pm
My understanding is the following: every time you save a jpeg in a non-parametric editor, there is additional degradation and it is cumulative. So, if you would just open and save it, say, 100 times, without even editing anything, you would degrade it 100 times cumulatively.

With parametric processing, no matter how many times you edit and save the file, you are going to degrade it only once, thus minimally.
Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: jeremypayne on September 04, 2012, 11:43:52 pm
Well, having done a little homework on the matter I see that Lightroom is non-destrutive with JPEGS. Only on export does some degradation take place.  

Only if you export and recompress the image again as another JPEG ...

If you start with a JPEG and export a TIFF there will be no additional loss of information on export.
Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: maxgruzen on September 05, 2012, 12:01:42 pm
Ah, so it seems that if I want to preserve a JPEG exporting in a Tiff is the best. However I now have a 120mb file to deal with. From what you are saying exporting in a JPEG will only degrade it once; and that is minimal. Sounds like the way to go. As to my first post it is operator error. New camera...I tried out the HDR function....camera shake. Seems that I can not handhold an HDR process at 1/100 sec. For me, I will need to get the camera on something solid for HDR....Example:http://www.pbase.com/mordicai/image/145842832  I am having a blast with this camera. I'm 72, and come from 8x10 film( actually I think we use 18x18 in the military) all the way down to Leica's, but never a P&S. Fun.....very creative. Thank you all for the advice on JPEG's.I haven't shot a JPEG in in almost ten years and it seems that some things have changed.
Title: Re: Some RX 100 samples processed in LR4.2 RC
Post by: ErikKaffehr on September 06, 2012, 12:58:54 am
Hi,

I don't think that we get serious image degradation with JPEG. You could try to take a TIFF image convert it to JPEG and subtract the JPEG image from the TIFF. What remain is a difference image, it will be mostly back.

The two major issues I see with JPEG are:

1) Information is thrown away. Highlight and shadow detail that may be useful may be lost.

2) Sharpening is normally applied to JPEG images. If you rescale and sharpen a JPEG image it may show haloes.

What I have seen in my experiment was that an mazing amount of info was retained in the JPEG image, but in many other cases perfectly recoverable tonality may be lost.

Best regards
Erik


Eric I have been doing the same with my RX 100, but find that my JPEG files degrade after some editing in Lightroom. I have used JPEGS a few times to shoot with the camera HDR and love the results, but lose quality after Lightroom processing. I have been thinking of saving the JPEG to a
TIFF or DNG and working on that??