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And another M9 newbie: what is Adobe doing to my files


pimver

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Hi All,

 

As indicated, a M9 newb, but I have search these forums extensively to see what is already out there,

Please bear in mind the only thing I am trying to achieve is to get the correct lens-info and F-stop in Aperture 3.0, for my own reasons so please dont fight the necessity to have this or not.

So along these lines I had to familarise myself with the various Adobe products, like DNG converter, Lightroom, ACR and CS5.

Especially with ACR and CS5 I managed to, on a 1:1 basis open and save the file, and Aperture would see the required info. I have not found a bacth process for this, not have I ben able to get the various applescripts/services to work that are spread around the forums.

 

I shoot my M9 uncompressed and I was shocked to find out the various Adobe products, especially LR reduce my file-size by approx 50%.

Having worked all my life in IT, I am quite certain this kind of compression must be lossy, on top of that I have not been able to find anything within the apps to reconstruct the picture such that it come close to the original file-size, and if I check the forums i think I am right.

 

Couple of questions,

 

Is there any way I can at all times keep the current file-size and it's embedded information as it comes out of the camera, using LR for instance?

Alternatively, is there a batch process (in CS% or ACR) to open and save ( in the original form) a stack of DNG's out of the camera so I can open them in Aperture with the required info added?

Am I missing anything here, instead of having to spend time on this, or being forced to use LR only to find out my files are slahes in half, I would rather go out and improve on my picture taking

 

thanks for reading and bearing with (another) new user

 

Pim

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There is no direct coupling between M lenses and any M body, even digital bodies. The only reason for the 6bit coding on M lenses is to tell the camera what lens is attached. No electronic coupling. So the camera never knows what f/stop you are using. It only knows the lens and the max aperture value of that lens.

In other programs like Adobe Bridge and Lightroom the program reads part of the image info, which at first release of the M8 was hidden, that approximates the aperture value you used to take the shot. That info is derived by comparing the amount of light hitting the sensor/light meter and the light recorded by the little sensor that is just above the Leica Red Dot logo on the front of the camera.

Leica originally hid this info because it is not always, never, correct, it's just a approximation. But then either gave access to it or told Adobe and other software companies how to access it. So you will never get the correct aperture value you used. If you do it is purely dumb luck on the part of the camera. As to whether aperture can read and display this approximated value I don't know.

 

 

More then likely you are converting your M9 uncompressed DNG file to DNG on import of those images. This is a common error on the users part. There is a setting you have to un-check to stop this. There is no reason to do that and LR or Bridge/ACR/PS does not do that without you making that setting. Un-check that setting and LR will stop doing this. Even with M8 files, or any other type of RAW file, when converting them to DNG, even if the file is already a DNG file, the Adobe DNG converter will make the file smaller.

 

Aperture can read Leica M9 DNG files, I think (don't use Aperture as I don't use a Mac and even if I did use a Mac I wouldn't use Aperture).

 

Stop converting your DNG's to Adobe DNG's and you will get the full file size.

 

But most people that are using a M9 shoot Compressed DNG as there is nothing lost in the file letting the camera compress it and the file size is much smaller.

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Well after looking through the LR options for both the regular program and the Import dialog and looking through the help file I can not find a option to convert RAW files to DNG @ import. I can find such a option for LR2 but not for LR3. There is a option to convert to DNG after import but not during import.

 

You can try copying the files from your M9, using a card reader, to your hard drive first then import them to the LR catalog and see if these files are reduced in size.

 

But I suspect somehow someway your M9 is set to record Compressed DNG's and not set to Un-Compressed.

 

A M9 Compressed DNG Should be about 17MB\+/- in size. If this is the size you are seeing in LR then the camera is more then likely set to Compressed DNG.

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Found it. IOt is on the top on the Import dialog window. Copy as DNG. If you are using that option just click on Copy, second option from the left. The next time you use the Import feature to get images off a card the Copy option will be highlighted.

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Shootist, you are a star,

@ your 1st reply, i dig that, the fact that it is an approx of the F-stop is fine, this suits my purpose where I am using the info in establishing the characteristics of DoF of the M9. I have shot a number of scenes with different aperture settings to get a feeling how the DoF works out, among others in combination with bokeh

@ your 2nd reply, for sure my M9 is on "uncompressed"

 

Any experience with ACR, or anything else where I can batch process all files, without reducing the file size?

 

I did it on a 1:1 basis with ACR after which the file, with it's original size

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.......I shoot my M9 uncompressed and I was shocked to find out the various Adobe products, especially LR reduce my file-size by approx 50%.

Having worked all my life in IT, I am quite certain this kind of compression must be lossy, on top of that I have not been able to find anything within the apps to reconstruct the picture such that it come close to the original file-size, and if I check the forums i think I am right.....

Pim

 

 

Pim, No you are mistaken ;)

I answered some of this in another thread where you posted. I am sure that you are familiar with Zip file compression and know that those files unzipped are identical to their original form. This is just another form of lossless compression like that. One of our resident experts here (Sandymc) has previously explained it as Adobe using a lossless LZW type algorithm.. If it was done in camera then file writing to your card would slow down further.

 

There is no Raw data loss; nada, zero, zilch, keine, not even a teensy bit; Really!!!!!!!

All metadata is preserved as well.

 

Once again, search the Adobe User forum for confirmation if you wish. Several earlier discussions on this here as well.

 

Don't be confused by the compressed DNG option in the M9 menu. That is lossy compression but of a different (and non-linear) type to that in JPEGS for example. Many users and indeed Leica Camera themselves, consider that the difference is insignificant. That was the only option in the M8.

Also the brightness sensor on your camera does allow for an approximation of the aperture used and can be useful. In my experience I often get a number within half to one stop of the actual aperture used. It is also used for some flash functions but those are unlikely to concern most users.

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HI Geoff,

 

I can understand all that, and I probably miss something here again, but I have found no way to reconstruct the file to its original size, one of the strengths of the zip-file thought/approach

Once it is "cut in half", it stays that way.

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HI Geoff,

 

I can understand all that, and I probably miss something here again, but I have found no way to reconstruct the file to its original size, one of the strengths of the zip-file thought/approach

Once it is "cut in half", it stays that way.

 

Take one the files that has not been reduced in size by converting to DNG and open it in PS. Save that file as a PSD. Now take one of the files that has been reduced and open that in PS then save it as a PSD. I bet you the 2 PSD files will be just about the same size.

 

No you can not uncompress a DNG or any other RAW file that has been run through the Adobe DNG converter.

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uncompressed DNG 34.75MB

same file losslessly compressed by Adobe 20MB (example, varies according to content)

Each DNG saved as TIFF with no compression 103MB. Not just close. Completely bit for bit identical.

TIFF files have lossless compression options as well. A DNG is more or less a TIFF with some more super powers anyway..

 

Even John Nack will confirm this and not too many people know more about the subject!. If you still aren't convinced I give up. Just tell me what brand of Hard drives you buy and I'll get some stock shares :)

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