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Request for CL files


jaapv

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I would love to get CL or any other files from you or your members.

The basic procedure is outlined here:

http://www.photonstophotos.net/Collaborations/Collaboration_Overview.htm

Cheers

Bill Claff of http://www.photonstophotos.net/ has requested CL files to be able to add the camera to his sensor comparison page.

 

See the link in the quote.

 

The site is highly interesting for technically inclined photographers and well worth a look. It depends on voluntary submissions.

 

Disclaimer: I have no connection to the site and am not aware of any commercial intentions.

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I'm intrigued.  The link in the quoted message doesn't work.  From the main page of the website, it appears that he needs raw files taken at many different shutter speeds and ISO levels, all with exposure compensation +1, focus at infinity and the lens right up against a uniformly bright target, such as a computer screen showing a single color.  He gives an email address for more information at his website.  If he answers me, I'll post some further information.  Wouldn't we all like to know how dynamic range changes as you push up the ISO.  And his charts show the dip in dynamic range at ISO 100 (it's lower there than at 50 or 200) in the SL.

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I'm intrigued. The link in the quoted message doesn't work. From the main page of the website, it appears that he needs raw files taken at many different shutter speeds and ISO levels, all with exposure compensation +1, focus at infinity and the lens right up against a uniformly bright target, such as a computer screen showing a single color. He gives an email address for more information at his website. If he answers me, I'll post some further information. Wouldn't we all like to know how dynamic range changes as you push up the ISO. And his charts show the dip in dynamic range at ISO 100 (it's lower there than at 50 or 200) in the SL.

+1.

 

Re SL: Exactly the reason that ISO200 is my base ISO. If longer shutter speeds are required, I go to ISO50.

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I'm working with Bill Claff now. First step is to identify two-stage amplification in the CL's profile. He thinks there is something similar happening between ISO 100 and 400 in the CL.

Thanks - much appreciated. And please Report back!

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I've turned in the files needed for Claff's analytics on the CL.  Expect to see things like noise levels and dynamic range profiles by next week.  And he'll be happy to do the same for the M9 and M8, which were missing from his data sets.

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Results for the CL are now posted at http://www.photonstophotos.net/Charts/PDR.htm on interactive charts.  The link goes to the dynamic range chart but there are others.  Here's the bottom line for the CL: https://www.dpreview.com/forums/post/60768252?image=0 

And the take-away message is that there are effectively 11 stops of range at ISO 100.  DR decreases at essentially one stop per step in ISO all the way down.  There is evidence of a little boost to help things above 400, but no reason to adopt ISO 400 as a base ISO. 

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Some comparisons that might be of interest:

 

Current Leica models:

 

39361017655_a99ea8386a_o.pngScreen Shot 2018-02-14 at 9.33.24 AM (2) by scott kirkpatrick, on Flickr

This supports avoiding ISO 100 in the M240 and SL, basing them at ISO 200, and the M10 and CL at ISO 100

 

Comparable less than full frame cameras:

 

39361017315_4ca116dfd5_o.pngScreen Shot 2018-02-14 at 9.41.11 AM (2) by scott kirkpatrick, on Flickr

 

Here you can see the advantage that APS-C has over M43 (50% more pixel area), and the fact that the CL seems to be the only one that is not "pulling" to offer ISO less than 200.  (Well, I guess Olympus has some tricks up their sleeves.)

Edited by scott kirkpatrick
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Leica M8 and M9 data on dynamic range at various ISOs (and much more, like detailed noise measurements) have been added to the PhotonstoPhotos site:http://www.photonstophotos.net .  But here is a summary:

 

39677225574_693d9846d1_o.pngScreen Shot 2018-02-20 at 9.50.08 PM (2) by scott kirkpatrick, on Flickr

 

I included the Olympus E-1 since they used a 5MPx CCD sensor with essentially the same technology that Leica built on (with microlenses added) for the 10 MPx M8.

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