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M8 Feature Options


Guest guy_mancuso

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Hello!

Which is exactly the reason one should expose correctly for the highlights and use the remarkable shadow recovery possibilties of the M8 to balance the exposure of the image in postprocessing. The shadows behave like they are 16/14-bit as far as I can tell.

Let me give you a simple example:

In the highlight region, you can calculate the following errors for the given 14 bit values:

 

16000 - 16065 compresses all to 8 bit value 253 which decompresses to 16002. The maximum error is -0.4%

16066 - 16192 compresses all to 8 bit value 254 which decompresses to 16129. The range of error is 0.3% to -0.4%

16193 - 16320 compresses all to 8 bit value 255 which decompresses to 16256. The range of error is 0.3% to -0.4%

 

Now we look at the shadows:

 

0 - 18 compresses to the 8 bit values 0 - 8 which decompresses back in steps of 0,1,2,2,4,4,6,6,9,9,9,12,12,12,12,16,16,16,16.

Dependig on the rounding methode we have tonal errors in the range of 9% to -33%.

 

Everybody can imagin that applying more brigthnes to such 'dark colors' will give almost completely different 'less dark colors'.

 

This is the zig-zag line we can see in LFI for the reproduction curve with 8/14 bit compression.

After decompression, 19 possible values are now only 8 different values. These 19 values could have been 19 * 19 * 19 = 6859 different colors, and after decompression, we have only 8 * 8 * 8 = 512 different colors!

This is a worst case scenario, but no theorie or hypothesis.

Practice shows us, that if images are correctly exposed, this worst case should never happen...

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Hello!

 

Let me give you a simple example:

In the highlight region, you can calculate the following errors for the given 14 bit values:

 

16000 - 16065 compresses all to 8 bit value 253 which decompresses to 16002. The maximum error is -0.4%

16066 - 16192 compresses all to 8 bit value 254 which decompresses to 16129. The range of error is 0.3% to -0.4%

16193 - 16320 compresses all to 8 bit value 255 which decompresses to 16256. The range of error is 0.3% to -0.4%

 

Now we look at the shadows:

 

0 - 18 compresses to the 8 bit values 0 - 8 which decompresses back in steps of 0,1,2,2,4,4,6,6,9,9,9,12,12,12,12,16,16,16,16.

Dependig on the rounding methode we have tonal errors in the range of 9% to -33%.

 

Everybody can imagin that applying more brigthnes to such 'dark colors' will give almost completely different 'less dark colors'.

 

This is the zig-zag line we can see in LFI for the reproduction curve with 8/14 bit compression.

After decompression, 19 possible values are now only 8 different values. These 19 values could have been 19 * 19 * 19 = 6859 different colors, and after decompression, we have only 8 * 8 * 8 = 512 different colors!

This is a worst case scenario, but no theorie or hypothesis.

Practice shows us, that if images are correctly exposed, this worst case should never happen...

 

Your post makes a bit (or byte) clearer this 8/10/16 discussion.

 

This is also interesting:

 

http://www.leica-camera-user.com/215345-post123.html

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Guest guy_mancuso

I already got a answer

 

 

Dear Guy,

*

Thank you very much for your efforts to make the LEICA M System even more successful. We will consider the proposals very carefully either for upcoming firmware updates or new products.

*

Again, thanks a lot!

Mit freundlichen Grüßen / Kind regards

Stefan Daniel

Leica Camera AG /*Product Management Leica M-System

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Guy,

 

One thing that has been a little frustrating is that the camera does not let you format cards with the baseplate removed. Really slows things down when you are shooting a lot and clearing a bunch of cards. Also, it would be nice to be able to change settings/menu items and preview files with the baseplate removed - again, would speed things up when you are confirming what is on which card. I hate having to keep putting the baseplate on and taking it off - and its even worse if the camera is on a tripod - a little practical thing that would help it work better as a professional camera.

 

Per

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This comparison can surely be approximated, by using equivalent lenses on M8 und DMR. But do those lenses exist in reality?

 

I have the 90mm APO Summicron for both the DMR and the M8. What would you have to use for a test target? I have an IT8 target. Will that do?

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I already got a answer

Guy:

 

How nice to get such a speedy answer from Stefan Daniel. I think it show's Leica's concern for its users, and reflects as well just how much they respect your commitment (and countless otheres in this forum) in spearheading some important firmware changes.

 

Live long and well,

 

Craig

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Guest guy_mancuso

Thanks Craig I appreciate that . I got a answer overnight which ws very responsive. Okay send me my filters now , i have been a good boy. LOL

 

Still waiting

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There's just no single digital camera which lets people formatting the cards with the CF door open.

 

 

Hi,

 

Actually, my P45 lets me format with the door open - not that I need to. Also, there is really no need for a DSLR to be able to reformat with the door open - you can just close the door.

 

However, if you are shooting off a tripod with the M8, then you have to basically take the camera apart, put it back together again and take it apart to be able to format discs and replace them. Far too much fuss.

 

As far as the safety issue is concerned, people should really be able to keep track of what buttons they are pushing and when.

 

Personally, I have found it to be a pain to have to remove the plate from the tripod and put it back on when clearing off discs and confirming the info contained on them.

 

Good luck with the other requests - look forward to seeing some of them implemented.

 

Per

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Thanks Craig I appreciate that . I got a answer overnight which ws very responsive. Okay send me my filters now , i have been a good boy. LOL

 

Still waiting

Guy:

 

Yeah, I could sure use mine, too. Oh wait -- my M8's still in Solms! I'll probably get the filters back before the camera. I actually loaded some Kodachrome into my MP the other and shot about 10 pix when my eye caught a strange purple glint from the front of my Tri-Elmar -- realized I was shooting with the 486 mounted on it, hadn't shot film for so long. Bet those will be some nice looking 'chromes.LOL

 

Live long and well,

 

Craig

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I knew we would have a bunch of SLR people trying to tell Leica how to make their rangefinder digital better. I just knew this was coming. Leica are the pros at this. Let them do their business. They have dedicated professionals working on this camera. They think about these things without our help and implement or not based on technical reasons that some of us dont comprehend. Field testing and discovery of glitches is one thing. Lets take pictures and let Leica make cameras and lenses! And hey Leica-please don't make the M digital series a super-feature oriented camera like an SLR, keep it simple like you always have with the M line for this is the reason for its success. And for those hopping over from using SLR's please stick around a while (years not months) and get to know rangefinder photography without trying to change it into SLR photography, you may find that the simplicity and the craft of rangefinder photography enhance your skill and enjoyment without all the slick features......B

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Guest guy_mancuso

Bradley i don't disagree , it should be kept simple. If i had my way out of this list. I would only want . 2,3 and a 24 1.4. Than 8 and 9 would be nice. But that's me and i have different needs than others and i don't want bells and whistles . i already left canon a couple years ago

 

 

 

1. Lens selection option "in menu" Generic 15, 21,24,28,35 otherwise with coding it is automatic regardless of setting

2. Optional 16 Bit setting like the DMR or better option

3. EV/ISO option with controls of either arrows or wheel , protect or set buttons. Whatever is fast and confirmed. Idea flash in VF what was set when confirmed

4. B&W optional b/w review, without having to write JPEG

5 Warning of non coded lens

6. Full name of lens in EXIF data sample 50mm summilux 1.4 as it is read by the coding

7. 15mm F4, 24mm 1.4 or F 2 , 28 1.4 ( some really fast wide angles )and than a line of lenses like the 28 2.8 that will be less costs like a 75 2.8 , 90 2.8 or think about 1.33 image circle digital specific lens

8 SDHC compatable or new standard This is not a leica call per say but industry standard

9 Travel charger smaller

__

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Guy,

 

As someone who spent two full days and swelled the profits of my local art supplies shop buying about 15 various ink/paint markers, totally without success in manual lens coding (the only indication I ever got was a 90mm), I would be very keen on item I. The rest of your laundry list is absolutely great and may I join the rest of the forum in thanking you for giving up so much of your valuable time helping us.

 

I assume that 1.10 will cure the green JPEG's with filter fitted and improve the auto WB, which even without filter on my 21mm, looks on the greenish side to me after 1.092. Sure I can batch them on PSE4 for auto colour correction but on PSE4 sadly you can't batch for colour cast removal, so the 300+ images I took in Barcelona will all need individual attention before I decide if they are keepers or not. I know I should have used DNG but knowing how busy I was going to be over the next two weeks, I was lazy and went the JPEG route - that will teach me.

 

Wilson

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