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dcsang
10-28-2006, 07:17
Let me preface this post with the following: I do not own nor have I seen an M8. I am going by reliable information that I have from a trusted source; one whom I have known for a number of years and one who has seen and has images from a production body.

Now, what I have heard is that the M8's images; at least at 320 ISO (as I was told) had excessive amounts of moire. There was "purple fringing" everywhere as well.

I was surprised to say the least after reading all these threads here claiming the quality of the M8 being up to snuff.

I asked what lens was used (since the Chromatic Aberrations are usually a product of the lens to the best of my knowledge) and was told that the shots were take with the brand new Leica 28mm. Again, a bit shocked, as this is a brand new production lens released along with the M8.

Do I believe this? Well, I want to see the images first and hopefully I'll be able to do so at some point in the coming week.

The story is that a certain "local to me" online luminary has a production M8 body and the 28mm lens tesing out before producing a review. This particular person dropped into a favourite haunt of mine and one thing led to another and these comments (re: purple fringing and moire) were made by my source and NOT the online luminary. One thing my source said to me was, when I asked what the images reminded him of, "they look like they came from a Kodak 14N . . . " That was what really disappointed me.

That being said, as I have stated, I have not seen the images so take what I have typed for what it may or may not be worth. I would be extremely disappointed if the M8 exhibited such behaviour as Leica is banking a lot on this imho.

Dave

Gid
10-28-2006, 08:11
I hope you are wearing your asbestos suit :D The fire department are on standby :)

BTW the Kodak 14N was rated very highly up to ISO100. DR and colour rendition were regarded as very good indeed, so if Leica have got as good as the Kodak's image quality and improved the noise, that can't be bad.

Olsen
10-28-2006, 08:35
- I don't believe this. But. What we shall be prepared for is that Canon's EOS 400D delivers files that are just as good. Even better in some respect, as low noice on high ISO.

icebear
10-28-2006, 08:38
Hi Dave,

I’ve seen an approx. 16x20’’ printout made on an Epson 2400 from a picture taken with a M8 [firmware vers. 1.06] with the latest 50 Summilux. The guy who took the picture and printing was in a hurry getting it done and not an expert in the digital workflow according to himself and obviously no one can claim to be an expert with the M8 yet. And this picture looked pretty darn good to me. Looking very closely you could detect slight moire in red areas of the US flag. I have no doubt that this could still be optimized using different settings. I have no info on the ISO rating the picture was taken at. Let’s wait and see for some more official work shot with the M8. I would not give too much about obviously negative comments at this stage.

jaapv
10-28-2006, 08:48
I always have problems with " an unnamed friend who is supposed to be an expert says..." type of reviews. I tend to believe guys like Sean Reid, Phil Askey and others...

boilerdoc2
10-28-2006, 09:27
Say hi to Michael R for me!
Steve

thurows
10-28-2006, 09:34
Morié becomes more apparant when you shoot something with a small distinct pattern like a herringbone suit. There use to be a bunch of filters around in the late 90s for use on cameras that didn't have an AA filter. Maybe they'll pop their heads up now that the M8 is out.

dcsang
10-28-2006, 09:45
Say hi to Michael R for me!
Steve


Shhhhh...

According to Jaap ... this guy is unnamed :)


Dave

jaapv
10-28-2006, 09:46
No asbestos suit needed as far as I'm concerned :) If it is M.R., I'm sure he'll write so in his review....
To come back to the original post: We did see purple fringing on one shot on this forum already. It was hardly surprising: The lens was a Noctilux wide open, the situation was OOF 100% contrast. No surprise to see a purple fringe then. The Noctilux was uncoded, and superb lens though it is, no one would call the old dear apochromatic...
As for Moire: there is a tradeoff between detail rendering and anti-aliasing. The balance struck by Leica seems to give extremely good pictorial rendering. However, I have one DNG file where I can see aliasing in the beard of the model. I think it was taken using beta firmware and I opened it in Lightroom. It may well be that the combination of the final firmware and Capture One will surpress the moire a bit more. Having said that, I really had to look for the aliasing.

John Camp
10-28-2006, 11:52
Outback Photo has posted an M8 downloadable 10mp RAW file of one of their common test subjects here:

http://www.outbackphoto.com/reviews/...8_review.html#

If you greatly enlarge the shot, you will find purple fringing on brilliantly lit metallic surfaces (look at the front wheels on the car on the right, or the gas cap on the car on the left and some other possible artifacts on the right side letters of the sign on the building (on the B.) I had mess around with the file for...uh, let me think here...about 14 seconds in Lightroom to get rid of it, at any size that I would actually print.

As for moire, I can't find any in this photo, but since there's no physical filter in front of the sensor, I would be surprised if there isn't any in photos with more severe tight patterns (like tweed).

This is a good shot to play with -- brightly lit outside, with a variety of forms and colors. But since this is the 39th shot taken with the camera, I'm not fully confident that the shooters are yet completely in control of the camera (although Uwe has a lot of experience will all kinds of cameras, and his reviews and commentaries are excellent.) I'm also not fully confident that this is the latest firmware, since the file name on the thing is 0610R8, unless that R8 is a complete coincidence. 8-)

JC

ywenz
10-28-2006, 14:03
From the DNG sample, it is obvious that the M8 has some serious purple fringing issues. The lack of the AA filter means very sharp details, as evident, but also jagged lines that are not perfrectly horizontal or vertical(See the chrome trimming on the Accord) You can compare 100% crops from my 5 year old D30, my cheap Canon A70 P&S and the more modern 20D:

M8:
http://img209.imageshack.us/img209/6172/untitled2wr6.jpg

The Canon DSLRs shows NO purple fringe in areas of high contrast (blown out whites and dark backgrounds) The D30's rendering of the highlights are spectacular! What a feat for circa 2000 technology!
D30:
http://img238.imageshack.us/img238/7240/img6599mq6.jpg

20D:
http://img230.imageshack.us/img230/9015/untitled1ur1.jpg

The little P&S shows purple fringe, which is acceptable for what it is.

A70:
http://img204.imageshack.us/img204/3531/untitled5xh5.jpg

I'm guessing these issues with the M8 are sensor related, but hopefully, they can be resolved with new hacks at the firmware.

Bob Ross
10-28-2006, 14:04
Outback Photo has posted an M8 downloadable 10mp RAW file of one of their common test subjects here:


As for moire, I can't find any in this photo, but since there's no physical filter in front of the sensor, I would be surprised if there isn't any in photos with more severe tight patterns (like tweed).


JC
Hi John,
While "tweed" gets mentioned for moire potential, I think we will see it first on bridge railings, fences and architecture details. If you are aware that there is potential for moire in your shot, you can often alter the angle slightly, to avoid it. I supposed that could be called side stepping the issue:D ......or maybe, side step bracketing:cool:
Bob

Magnus
10-28-2006, 14:06
hey... it' a digital camera ..

purple haze, orange fringes red whatevers are part of the game ...

Gabriel M.A.
10-28-2006, 14:14
I always have problems with " an unnamed friend who is supposed to be an expert says..." type of reviews. I tend to believe guys like Sean Reid, Phil Askey and others...
Hear hear.

I know somebody who talked to the sister of a coworker of the in-law of the receptionist of the uncle who has personally shaken the hand of the grandfather of the driver of Charles de Gaulle's hairdresser. She said color film was all the rage. :eek:

Very reliable source.

Olsen
10-28-2006, 14:18
Moire is a hell of a problem on 1Ds II too. If you shoot cloth patterns of certain types the groom looks like a vocalist of a dance band. I am sure it is not solved on the M8 either. Hasselblad claims you have to have 39 million pixels to get rid of it. Moire is a curse of the digital age.

I am looking forward to see how hardware and software fixes the hard vignetting, AC and worse - the soft corners, that might be expected of a digital camera with such high angle light rays hitting the sensor. Vignetting can be easily fixed. A bit more difficult is AC. Soft corners; impossible. Resolution that is not there can not be added.

That said, I think Leica did a tremendous good job on the digital R. It is one of the very best pro D-SLRs that deserves success.

Magnus
10-28-2006, 14:32
Olsen,

thank god digital photography has supplied us with the means to increase saturation right up untill the amounts that please us ...

:-)

Magnus
10-28-2006, 14:36
Originally Posted by jaapv
I always have problems with " an unnamed friend who is supposed to be an expert says..." type of reviews. I tend to believe guys like Sean Reid, Phil Askey and others...

yeah me too ... the word of Rumsfeld, GWBush and the other "established" are water on my tongue for me ...

I mean, really how could they be wrong, millions of people listen to them... and ahhh, I also believe everything I read in the newspapers ....

Bob Ross
10-28-2006, 14:49
From the DNG sample, it is obvious that the M8 has some serious purple fringing issues. The lack of the AA filter means very sharp details, as evident, but also jagged lines that are not perfrectly horizontal or vertical(See the chrome trimming on the Accord) You can compare 100% crops from my 5 year old D30, my cheap Canon A70 P&S and the more modern 20D:

I'm guessing these issues with the M8 are sensor related, but hopefully, they can be resolved with new hacks at the firmware.
Hi Ywenz,
I think your "serious" adjective is probably an exaggeration in keeping with your usual style:)
Real purple fringing has been traced to Lateral chromatic aberration in lenses and is defined: "Variation of image size according to color. Color fringes are created around images of white objects near the limit of the lens field. An off-axis fault unaffected by stopping down."
Chromatic aberration is different and caused by different colors focusing at different planes in non-Apo lenses. It is reduced by stopping down. I suppose the question to be asked, since Leica optics are very well corrected, are the off-set micro lenses contributing in some way.
The lack of an AA filter simply lets the sensor define the aberrations better along with all the fine detail, for which everybody seriouly hungers. This sort of thing shows up in film, too, especially if you look as close as you do. The jagged edges are probably from the processing routine, rather than the Bayer nature of the sensor.
Keep up the good work. We need a serious peeper around here:p
Bob

JohnL
10-28-2006, 14:59
I have three potential concerns about the M8, two of which are raised in this thread:
1) Purple fringing: I also saw the Noctilux shot and it looked to me (hard to judge from the screen) like it was a hard edge of a blown highlight (white cup) against a dark background. This *could* be caused by CA but I rather suspect it might just be pixel overflow (aka "bloom"). We need to see tests of situations like this with exposure adjusted to avoid the blown highlights. I'm sure we will before long.
2) Moiré: I have the impression this will be an issue but rarely, and that when it occurs we'll be able to handle it in PP.
3) The alleged fact that I've seen mentioned both here and on LUF that the DNG files only contain 8 bits of data per pixel (despite the fact that Leica specs mention 16 bits quite specifically). Apparently Leica somehow is getting more than 8 bits of data per color channel from that, perhaps through keeping all the information (not rounding the results) from the demozaicing algorithm. In one sense this seems to go against the basics of information theory, but if it works in practise then great! There is additional information in the algorithm itself, of course, but whether there is enough to avoid posterization in PP only time will tell.
... these are the issues that I'm trying to find out more about.

jaapv
10-28-2006, 15:36
If you greatly enlarge the shot, you will find purple fringing on brilliantly lit metallic surfaces (look at the front wheels on the car on the right, or the gas cap on the car on the left and some other possible artifacts on the right side letters of the sign on the building (on the B.) I had mess around with the file for...uh, let me think here...about 14 seconds in Lightroom to get rid of it, at any size that I would actually print.

This is the thing that stuns me each time I play around with these M8 files - the speed and ease with which they post-process.
Starting with scanned film -I lay no claim to great expertise, but I think I'm no beginner either- let's just say life is too short... Before they are halfway decent I need about every trick in the book.
Then my Canod 10D, which taught me the basics:Convert from Raw after slamming all the automatic adjustments to zero, do levels and curves, contrast,finetune colour balance, complicated sharpening, 10 mins per file, then Digilux2, which taught me the ins and outs of noise reduction, but was better:5 minutes. And now the M8: Open in lightroom, a few clickes, export to PS, crop, a bit of Focal Blade, done in 60 seconds, perfect file ready for print. I love it!

Gabriel M.A.
10-28-2006, 15:40
OK, I downloaded Digital Outback's DNG file, used Adobe Raw (3.4), and like any of us who actually know something about digital workflow and the problems with CA in difficult situations, set the CA-correcting parameters. If it hadn't been for a few interruptions, this would have taken me about a minute rather than about five.

After a few steps, I uploaded. Moral of the story: don't just trust anybody's files to show what an instrument can do.

http://www.rangefinderforum.com/photopost/data/500/medium/sm_0610R8_0039.jpg

Sheez, I mean, really. Let the guys ship out the thing.

ywenz
10-28-2006, 15:46
Okay, compare apples to apples, to get true idea on what the output from the sensor is like. Take un-CA corrected M8 file and compare to un-CA corrected files from other cameras. Sheez, I mean really, that's just common sense...

dcsang
10-28-2006, 15:46
Hey... I've given enough hints in the initial post that you should know who the person is who's got the M8.

As for my "very reliable source".. I also stated that I personally have not seen the files myself but hope to do so this week.

Don't shoot me... I'm repeating what I was told and am disappointed to hear it (if it is true) as I would prefer to see the M8 succeed.

Purple fringing and moire I can sort of live with (and avoid hopefully) but I remember what the fiiles were like out of the Kodak 14n - They were craptacular for the amount of money that camera cost and were completely unusable beyond ISO100 - THAT is the thing that worries me the most wrt the M8 - Not even being able to have a usable ISO400 or higher would make the camera nothing more than a really good "daylight" cam.

Dave

jaapv
10-28-2006, 15:48
Originally Posted by jaapv
I always have problems with " an unnamed friend who is supposed to be an expert says..." type of reviews. I tend to believe guys like Sean Reid, Phil Askey and others...

yeah me too ... the word of Rumsfeld, GWBush and the other "established" are water on my tongue for me ...

I mean, really how could they be wrong, millions of people listen to them... and ahhh, I also believe everything I read in the newspapers ....
Well, to be really truthful, the only one I really believe is myself- I'll let you know as soon as I have played around with my own M8 -if you promise you'll believe me ;) But you're right in a way- Deep Throat was more reliable than Nixon. Fortunately camera-reviewers are not politicians :D

x-ray
10-28-2006, 15:55
I would certainly expect moire from a camera with no AA filter. This what the AA filter reduces. Without it your image is sharper but at the expense of moire. The chromatic aberations are just a part of lenses, even leica lenses. If you're a digital shooter get used to it. It's easy to remove the effects of chromatic aberations in photoshop in both the raw converter and under the filters / lens function. It's no big deal. Without the AA filter you will have purple artifacts around branches of trees / fine details and particularly when back lit. Welcome to the digital world. Nothing against the M8 but it's just a fact of digital life.

Gabriel M.A.
10-28-2006, 16:14
Okay, compare apples to apples, to get true idea on what the output from the sensor is like. Take un-CA corrected M8 file and compare to un-CA corrected files from other cameras. Sheez, I mean really, that's just common sense...

Sheez, I mean really, I'm like, totally game:

http://www.rangefinderforum.com/photopost/data/500/2006-05-28_097-crop.jpg

http://www.rangefinderforum.com/photopost/data/500/2006-05-29_012-crop.jpg

Both 100% crop images from non-CA-corrected 20D RAW images.

ywenz
10-28-2006, 16:22
badass gab, badass..

jaapv
10-28-2006, 16:28
I think you've proved your point, Gabriel. And - may I add - these shots also prove the limited -to put it mildly- value of this kind of pixel-peeping.

Gabriel M.A.
10-28-2006, 16:42
I think you've proved your point, Gabriel. And - may I add - these shots also prove the limited -to put it mildly- value of this kind of pixel-peeping.
Pixel-peeping is inevitable. But, yes, it's so open to interpretations, who uses the camera, how, then the files. The 20D is fine, but it has its limitations. So is the 5D, but the CA still annoys the hell out of me; without any filter on the M8 whatsoever, I'm sure it's going to give a lot of ammunition to people who have no clue what that means. I believe this is why Leica went with the lens-coding route, so that there would be some "automatic" CA correction. A "software" filter. But on the Canons, it's there and that's that; final. Finito.

I am more worried at this point at the wild differences of the high ISO noise performance so-called reviews so far; not what I saw myself. So I don't know what's going on with these people's cameras and/or settings.

John Camp
10-28-2006, 17:53
Purple fringing and moire I can sort of live with (and avoid hopefully) but I remember what the fiiles were like out of the Kodak 14n - They were craptacular for the amount of money that camera cost and were completely unusable beyond ISO100 - THAT is the thing that worries me the most wrt the M8 - Not even being able to have a usable ISO400 or higher would make the camera nothing more than a really good "daylight" cam.

Dave

I had a couple of Kodaks, and in most ways, short of high ISO shots (say, up to about ISO 400), they were as good as a Canon 1Ds2 -- and the color was better. They are still used a lot in studio work, where, with controlled lighting, they *are* as good as the top-end Canon, IMHO. Landscape guys liked them, too, for the detail. But you did have to spend some time learning how to use them. And, with Kodak's multiple firmware upgrades, they kept getting better.

Their reputation, again, IMHO, was generally pulled down by Canon trolls; you had to be there to understand how ferocious that assault was. People who actually used them, though, tended to think they were prretty good for their time -- I mean, how many people make their livings shooting black branches against a bright sky? Reminds me of the 'banding' assault on the D200, with the lightbulbs shot against black backgrounds.

As for the purple blooming or fringing in Uwe's shot, it looks to me like he was trying to hold some detail in the white plaster surround on the building, while also trying to hold detail inside the restaurant window (notice the almost-black leaf reflections in the window, and the detail in the salt shaker.) The white plaster was essentially selected as his highlight. So you get the purple blooms on sun reflected off chrome, which is what, 4 stops higher than the white plaster? Six stops? Tell me about a DSLR of any make that will hold that, without doing something weird.

And (psst) is you have *any* competent post-processing software, it cleans right up.

JC

Bob Ross
10-28-2006, 17:56
This is the thing that stuns me each time I play around with these M8 files - the speed and ease with which they post-process.
Starting with scanned film -I lay no claim to great expertise, but I think I'm no beginner either- let's just say life is too short... Before they are halfway decent I need about every trick in the book.
Then my Canod 10D, which taught me the basics:Convert from Raw after slamming all the automatic adjustments to zero, do levels and curves, contrast,finetune colour balance, complicated sharpening, 10 mins per file, then Digilux2, which taught me the ins and outs of noise reduction, but was better:5 minutes. And now the M8: Open in lightroom, a few clickes, export to PS, crop, a bit of Focal Blade, done in 60 seconds, perfect file ready for print. I love it!
Hi JAAPV,
I have to agree with your observations. It may be the Kodak sensor family trait, since my E-1 is the same and even pro post processors agree. I am glad to see it with the M8. My three years with the E-1 have been a challenge to my compulsion to post process learned from film scanning and fooling with my first digicam, a Coolpix 5000. Hopefully the M8 will add another layer of compulsion therapy;)
Bob

John Camp
10-28-2006, 18:07
I am more worried at this point at the wild differences of the high ISO noise performance so-called reviews so far; not what I saw myself. So I don't know what's going on with these people's cameras and/or settings.

As far as I know, there have only be two reviews (or one and a half -- Sean Reid's review, and Uwe's partial reviewe on Outback.) And I think they pretty much agree that high ISO capture is good. Sean Reid says that the ISO is conservatively rated with the Leica, and that the 1250 setting is actually closer to a real 1600, and that the 2500 is actually closer to 3200. And the 1250 [1600] Reid says is pretty good, and I get the impression that Uwe also thought it was all right -- he says it's very usable and the color noise cleans up well, leaving good detail. Things start to break down at 3200 in Reid's review, but he specifically said that that was under the worst kind of mixed-light shooting conditions -- and even that cleaned up pretty well.

I think it's going to be fine.

JC

Peter Klein
10-28-2006, 19:45
Klein's First Law of Pixel Peeping states that "Sufficiently magnified, all photographs look terrible." I've learned that pixel-peeping is counterproductive unless you qualify it by how big you're blowing something up. Otherwise, it's like looking at a Monet painting from four inches away and declaring that the painter had sloppy technique.

So I made some prints of Uwe's file, a sun-lit shot at ISO 160. I opened the DNG file in Picture Window Pro's RAW converter, which is a fairly generic tool. I then used some fairly standard adjustments--just curves and a bit of USM. I easily got a file with levels and colors very similar to Uwe's JPG examples.

I then made letter-size prints of the file, both in color and converted to black and white. I also made a couple of 5x7 prints of sections of the file, blown up to the magnification of a 16x20 print.

At letter size, I just barely see the purple fringing on the car's chrome trim. It only bothers me if I "smell" the print. On the B&W print, it just looks like normal specular-highlight glare. At 16x20 magnification, the fringing is more bothersome. I also see some color artifacts at boundaries between the white plaster and darker shadows. There are also faint reddish rings around the number "160" on the restaurant door.

If I pixel-peep at 200%-400% magnification, I see significant color speckling in the gray molding that runs across the upper part of the picture just above the door. This appears to be not moire, but Bayer-pattern artifacting on tiny flecks of wearing paint on the molding. It's barely detectable at 16x20 magnification. I can also see an occasional false-color speckle on the plaster dome above the door, but this is only visible on the screen at 200% and larger--not in the final print.

To which, I say a rousing SO WHAT? The only extra work I would have needed on this file to print at letter size in color would be on the sun-reflection highlights. Most cameras, even the best, have this issue. Heck, I've gotten such fringing on such highlights on film scans. It cleaned up with a minute's work with a quick mask and the Moire reduction transformation in Picture Window Pro. For a 16x20 print, I would have needed to do the same thing on the dark grey molding above the door. For B&W, I wouldn't have needed to do anything extra at all.

It's possible that the Leica-tailored edition of Capture One supplied with the camera deals with these issues in the converter.

Apart from the above, the general impression of quality is pretty astounding. Sean Reid is right on--the prints indeed look like they were made from medium format negatives. The 16x20 magnification prints have unbelievably subtle details that I have not seen on samples from other digital cameras save the 1DSMkII. And unlike most cameras, these details hold with magnifications up to the point where you can see the individual pixels. With most other DSLRs, details "smear out" before you can see the pixels, probably because of the AA filter. If a few color artifacts represent the price one must pay for that level of detail, it is a worthwhile trade.

Despite what some less-informed people on digital camera forums think, there are laws of physics and some real-world trade-offs to be made in camera design. Based on what I've seen so far, I think Leica made some *very* good decisions on this camera.

--Peter

x-ray
10-29-2006, 04:43
Over the seven years that I've been shooting pro digital equipment in my studio the files have progressively been getting easier to post process. Since the beginning when I dhot the original D1 Nikon both software for post processing and the internal software in the camera has improved. Remember when you shoot raw the camera is not applying any adjustments to the file but the camera has embedded that data into the file so the post processing software knows what Leica, Canon or your preferences were when shot. When you post in some software that data is seen ans applied to the image unless you over ride it. This is the beauty of raw vs jpg or tif. You make the decisions on perameters. If the software does not read the embedded information then the designers of the software make that decision but again you can over ride it. My first D1 was a job to get right, the D1x, 1D and 1Ds canons and now the 1DsII all have become much easier to process. I don't think it's so much a function of the chip as I do the internal software and processing software.

Chromatic abberations and all the other little things that go along with digital files and pixel peeping are just a fact of life. Leica makes great glass but Canon and Nikon do too. All lense makers have chromatic aberations in short lensed, even Leica and Zeiss. When you look at a digital file like in the 1DsII at 100% you are effectively looking at a nearly 70 inch print at a foot or so. If you shot film and enlarged the image to that size you would see the same problem. How many times have you made prints thirty or forty inches in size and looked at the edges at four inches? It's not a function of digital but digital has given us the ability to examine the image closer than we ever would have in the past. Figure the magnification of a 1DsII file at 70 inches.

newyorkone
10-29-2006, 18:58
Pixel-peeping is fine but somtimes I think people can't see the forest for the trees...

Here's a 100% crop from the top-left corner from the original DNG saved to JPG. No sharpening at all. I think it looks pretty good and keep in mind that it's a corner no less. Of course the raw file looks even better and the shadow pixelation is from saving to JPEG.

EXIF information indicates that a coded 50 summicron was used and was shot wide open at f/2...

http://static.flickr.com/104/283149491_a8aafe17b7_o.jpg

Stan98103
10-29-2006, 19:19
I believe that the EXIF data can only tell what lens is on the camera (and the maximum apeture for that lens), not the actual apeture for a particular shot.

Cheers,

Stan

butter71
10-29-2006, 21:25
I believe that the EXIF data can only tell what lens is on the camera (and the maximum apeture for that lens), not the actual apeture for a particular shot.

the EXIF data is "Max Aperture Value" with a value of "f/2.0"

regardless, i thought that one function of the blue dot was to allow for an aperture approximation for the EXIF data?

Stan98103
10-29-2006, 22:15
The blue dot is an ambient light sensor, but it's only used to control the brightness of the LEDs in the viewfinder. It has no effect whatsoever on how the image is captured or processed or and it does read or estimate what apeture is being used.

If you open an M8 dng file in Bridge or PSCS2 and then go to File --> File Info and look at Camera Data 1, you can see which common parameters are recorded in the EXIF data. Additional EXIF data is found in Advanced under EXIF Properties and includes Exposure Bias Value (compensation) and white balance settings, as well as some other parameters. This includes an entry for exif:ImageUniqueID which is a 32-digit number that looks like a shutter release counter. You may have to have this reset before you take your 1 x 10^33 image on the M8. :)

Cheers,

Stan

butter71
10-29-2006, 22:23
The blue dot is an ambient light sensor, but it's only used to control the brightness of the LEDs in the viewfinder. It has no effect whatsoever on how the image is captured or processed or and it does read or estimate what apeture is being used.

that disagrees with the latest LFI (p28) - "This sensor measures the light independently from the one inside the camera. The aperture value is then simply calculated by subtracting the light travelling through the lens from the exterior lighting" [...] "the values for aperture and focal length are subsequently stored as Exif info in the image file"

Nachkebia
10-29-2006, 22:39
Oh my, IT talks are here! get ready for transformation forum! from photography to computer hardware! :D

Stan98103
10-29-2006, 22:54
I haven't seen the LFI article, but the M8 User Manual that's online indicates that the blue dot is just an ambient light sensor to control the brightness of the LEDs.

If the blue dot were functioning as stated in the LFI article, why wasn't an apeture value recorded in the Digital Outback dng? Perhaps the LFI article is wishful thinking for future upgrades.

Perhaps Sean can clarify this.

In any case, the M8 is a wonderful camera and the lack of f-stop data in the EXIF file is of little consequence as far as I'm concerned.

Cheers,

Stan

wpb
10-30-2006, 03:04
Maybe the aperture recording function (and even the jpeg lens optimization) is not working with the firmware loaded on the sample cameras. This could be why Leica is so adamant about posting images from the cameras as the cameras that actually ship may have the latest firmware enabling all functions as per the LFI article.

jaapv
10-30-2006, 03:15
Well, Michael Reichmann's is up at LL. that puts an end to that: I have seldomly ifever read such a positive camera review. He himself calls it "gushing"and does not even apologize for it :);)

devils-advocate
10-30-2006, 04:24
There was no moire or colour fringing on any of the numerous images I have seen from a production M8. In fact, I have never seen a digital camera reproduce complex fibre-patterns in clothing with more realism. Incidentally, there was also no discernable noise in 11x14 prints at ISO 640. :)