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Today I have just had a trial run with a CL with a view to buying, my first ever use of a Leica.  I have had an Olympus OM-D EM-5 for several years, it has a 15MB sensor.

Here are the file sizes from today's trial:   (All have 300 pixel resolution

Leica CL.                       Leica DNG.            Leica jpeg OOC (unprocessed).            Leica jpeg (post-processed in Affinity Photo)     

                                        44.2 MP                            7.4MP                                                       12.5MP             

Olympus                           RAW.                                  -                                                  Olympus jpeg (post-processed in Affinity Photo)

EM-5.                              14.0                                      -                                                               9.2MP

The main reasons to buy the Leica are the ability to make larger crops & print larger, another is an upgrade in quality. But I am very surprised at what seems to be the small size of the jpegs from the Leica. The processed Leica jpeg is 3.5 times smaller than the DNG, The Olympus jpeg is just 1.5 times smaller and I'm puzzled.  Putting image quality aside, as far as I can see, the CL doesn't give me a sufficiently increase in image size to warrant a purchase.  

I really want to buy the CL with the Summilux 35mm f/1.4 TL but.........................Any help/advice would be most appreciated.

David                                            

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The Leica gives you 44Mpx to play with. The Olympus on 14 Mpx.

If you are looking to print larger, forget the jpg compression, and focus on the file dimensions. If you are serious about printing, you won't be using 8-bit jpgs.

How big are the actual RAW/DNG files that the two cameras produce? (Do you have DNG compression switched on with the CL?)

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Thanks for the reply Andy.  As per post, the DNG files from the Leica are 44.2 MP, the raw files from the Olympus (vintage 2012) average 14MP.  I have comfortably printed 50cms x 37.5cms from the Olympus jpegs - with minimal cropping if any.  I would like the option to print larger to say 75cms x 50cms from the CL.

My lack of technical expertise means I am floundering re your sentence.  "If you are looking to print larger, forget the jpg compression, and focus on the file dimensions. If you are serious about printing, you won't be using 8-bit jpgs".  Affinity Photo recognises the Leica DNG as a 16-bit RGB file but it is my understanding that the jpg format does not support 16-bit, at least that's what one poster on the Affinity Forum states and this seems to be supported as the RAW/DNG Export (as jpg) option does not offer 16-bit.  I am seriously out of my depth here and print using a photo lab that stipulates that files need to be jpgs and with 300 pixel resolution.  If it's not asking too much, can you suggest a step by step guide to go from DNG to a jpg for this idiot and does the jpg file size matter?

Thanks

David

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6 hours ago, David Cantor said:

Leica DNG.            Leica jpeg OOC (unprocessed).            Leica jpeg (post-processed in Affinity Photo)     

                                        44.2 MP                            7.4MP                                                       12.5MP             

You did not choose the higher jpeg resolution i suspect. Go to main menu page 2 and choose "JPG Resolution: L-JPG". Your jpeg file should be about 13mp then and after conversion of the dng file in PP, the resulting tif file should be about 140mp. Plenty room to work :).

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Hi lct

The images were taken in a dealer's showroom and the camera handed back so I do not know what the jpg setting was.  I rarely if ever shoot jpegs so the OOC file size is a red herring, it's the size of the converted dng files that I'm interested in.  If I convert the dng file as a tif, the 8-bit file size is 21.96 mp, as 16-bit the file size is 105.54mp.  Please refer to my reply to andyburton, I need jpgs for printing or am I missing 'the bleeding obvious'?

Cheers

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7 hours ago, David Cantor said:

Today I have just had a trial run with a CL with a view to buying, my first ever use of a Leica.  I have had an Olympus OM-D EM-5 for several years, it has a 15MB sensor.

Here are the file sizes from today's trial:   (All have 300 pixel resolution

Leica CL.                       Leica DNG.            Leica jpeg OOC (unprocessed).            Leica jpeg (post-processed in Affinity Photo)     

                                        44.2 MP                            7.4MP                                                       12.5MP             

Olympus                           RAW.                                  -                                                  Olympus jpeg (post-processed in Affinity Photo)

EM-5.                              14.0                                      -                                                               9.2MP

The main reasons to buy the Leica are the ability to make larger crops & print larger, another is an upgrade in quality. But I am very surprised at what seems to be the small size of the jpegs from the Leica. The processed Leica jpeg is 3.5 times smaller than the DNG, The Olympus jpeg is just 1.5 times smaller and I'm puzzled.  Putting image quality aside, as far as I can see, the CL doesn't give me a sufficiently increase in image size to warrant a purchase.  

I really want to buy the CL with the Summilux 35mm f/1.4 TL but.........................Any help/advice would be most appreciated.

David                                            

It looks like you are confusing megapixels and megabytes. The CL has a 24 megapixel sensor (that is what '6016 px x 4016 px' in your screenshot means ~ 6000 * 4000 = 24,000,000). If you take a DNG file from the camera and convert it to tiff, the tiff will have 24 million pixels. That will be the case for both 16-bit or 8-bit tiffs, but the 16-bit files will use more space to hold the greater bit depth. It's correct that jpeg files can only be 8-bit. If the converted tiff file is saved as a jpeg, it will still have 24 million pixels. The actual file size of a jpeg depends on its resolution and on the specific compression settings of your software package. If you shoot jpegs in-camera, these can either be full-resolution 24 megapixel files, or some lower resolution you set in the menu, which will also affect the file size. If you're shooting DNG, converting to jpeg should be pretty much the last thing you do, after making all adjustments in your editor and ideally saving a version in some file format that doesn't apply lossy compression first.

What is your target print size? Don't resample the image unless you need to. From a 24 megapixel image you should be able to print up to the dimensions in cm shown in your screenshot at 300 pixels per inch without resampling. Is 51cm x 34cm big enough? Your Olympus gives you 4608px x 3456px images, which at 300 PPI corresponds to a size of about 39cm x 29cm.

Edited by Anbaric
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The Olympus makes pictures with ~16 MegaPixels, i.e. with 4.608 x   3.456 dots.

The Leica CL makes pictures with ~24 MegaPixels, i.e. with 6.016 x    4.014 dots.

Hence, at the same magnification factor the Leica will yield pictures 1.3 times as tall and 1.16 times as wide.

The 300 dpi metric is meaningless in that context. The dpi refers to the density of the image dots (pixels) on the paper print and is completely useless when speaking about images on storage cards.

If your copy service only accepts JPEG pictures, you should export your pictures at the highest available quality, i.e. 100% (or no compression at all). Even so, the quality will suffer. For serious printing, you should insist on the TIFF format. You might want to look for another copy shop.

   
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vor 15 Stunden schrieb David Cantor:

... or am I missing 'the bleeding obvious'?

Yes, you are. Actually you are confusing the heck out of everything. File size, pixel count, resolution, etc ... obviously you have no idea what all these terms are about. So, MB is not MP. File size is not pixel count. DPI is not PPI. Input resolution is not output resolution. Format factor is not magnification. Data compression is not image quality ... and so on and so forth.

Maybe you should take a digital image processing class, near your home town or online ... in order to be able to understand what you—and we—are talking about.

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Olaf and others

Thank you for all the input.  Until now, I never had any problems printing & sizing because the image size from the camera equated closely to the size of my print and yes, my understanding of these terms needs to improve.  Plus, I found that there are print labs that print from flattened tiffs as well as jpegs.  I have been asked to exhibit about 20 of my images, wanted the best combination of size and quality hence the CL trial.  I understand that there are many cameras with much larger sensors but I am looking for a combination of portability, size and image quality that fits within my budget.  The CL (second-hand) matched with the 35mm Summilux f/1.4 seemed to fit the bill.  

It's over to YouTube

Edited by David Cantor
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