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M8 hideous unusable high ISO performance thread


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This one is 4-stops down, so ISO2500 equivalent. Used Auto-Curves and then pulled up the curve a little bit to bring out the face. It was very dark, hard to nail the focus.

 

16388807196_929a5afeee_o.jpgiso2500eqv

 

The lens used might be the only Rangefinder coupled Minolta 50/1.4. Hacked lens on the M8 using Hacked shooting modes.

 

11655184923_6bcc007231.jpgMinolta1

Edited by Lenshacker
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So my new project is to write up how I got from "A" to "B" on some of these examples. I'll make it into a PDF when done. I am putting images into it, for illustration. This will be for a WINdoze machine and requires use of the command line. I will include screen captures.

 

I have the intro done:

 

"The Leica M8 is now more than 8 years old, is Leica’s 1st generation M-Mount digital camera. Some design compromises were made, including the lack of uncompressed DNG as was available in the digital back for the Leica R-Mount SLR. The latter used CF cards, much faster than the SD cards used in the M8. SD cards are small, much simpler interface. The write speeds of the SD card was stated to be too slow for uncompressed DNG, and compressed DNG-8 was implemented in firmware. High-ISO performance suffered as a result of this decision.

“Put the computer into diagnostics mode”, a favorite trick of Mr. Spock. The button dance is born, most likely some Leica firmware engineer was a fan of the Rocky Horror Picture Show and implemented the “TimeWarp” dance. Push the Right arrow key 4 times, Left arrow key 3 times, Right arrow key once more, and then press “Set”. Scroll down to “Compression”, press Set to enter the sub-menu, , and you will see a new option: “ Fine Jpeg+Raw”. Scroll down to select it. One word of caution: if you plan on using this mode for extended periods, disable the “Auto-Off” mode of the camera. Once you turn the camera off, or if the camera “hibernates” to save power- the setting will revert to “Fine Jpeg” only. You will need to do the Button Dance again.

 

You will have to put up with my sense of humor...

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I have Ektar 100 in my Nikon FE right now and Kodak TX 400 in my Hasselblad. I am having no trouble shooting anything and if I really need a photo indoors I plop my Leica flash on the FE and I'm good to go. If I want to shoot my Manchester Terrier sprinting full speed in low light I grab the Nikon D3 and set it to 10fps.

 

...different tools for the job

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I have a Nikon Df, M9, and M Monochrom. They all work well in low-light. Not everyone owns them, and this is the M8 forum.

 

Arvid's M8RAW2DNG puts the M8 on par with the M9. There are M8 owners that might want to take advantage of the low-light capabilities that are inherent in the camera that have been masked out by the firmware. That is what this thread is about.

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As a fairly new owner of a m8.2, [...]

 

I'd be interested to know if anyone has any thoughts on boosting exposure in post, versus raising the ISO in-camera. Are there any Signal to Noise Ratio benefits from shooting in ISO 640 and then boosting by 2EV in post, versus shooting at ISO 160 and pushing 4 stops in post?

 

Just go to the first post in this thread for an answer.

.

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"The Leica M8 is now more than 8 years old, is Leica’s 1st generation M-Mount digital camera. Some design compromises were made, including the lack of uncompressed DNG as was available in the digital back for the Leica R-Mount SLR. The latter used CF cards, much faster than the SD cards used in the M8.

 

The DMR uses SD cards

 

john

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The DMR uses SD cards

 

john

 

I did not know that- thankyou. I've corrected it in the draft.

 

It just makes me wonder why-on-Earth Leica did not include Uncompressed DNG with the M8!

 

This is an ISO2500 Equivalent shot.

 

16422337455_5ae5e5261d_o.jpgNight_Fight_Color_ISO2500eqv

Edited by Lenshacker
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Following my own instructions, all now with screen shots...

 

LR to CS2 auto-levels, then some slight adjustment in curves.

 

Shutter set to 1/90th, was very dark. This is at least 5 stops under.

 

I sent the draft to Arvid for review.

 

Very impressive indeed. Really looking forward to reading the steps you took to achieve this result!

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I will be revising the instructions based on Arvid's input and tips on how to improve the results shown so far.

 

On the ISO setting, this is from the draft I am doing:

 

" Leave the camera set to Base ISO of 160 and use the EV compensation setting to shoot at higher ISO. For ISO320 use EV-1; ISO640 use EV-2; and ISO1250 use EV-3. After that, you need to use manual exposure. Setting the compensation to EV-3 on the M8 controls both Auto-exposure mode and manual metering mode. In manual, the center Dot indicates exposure with the compensation factored in. I use EV-3, match the dot, then select a higher shutter speed for ISO2500, ISO5000, and 10000. The latter, to see what the camera could do.

Setting the ISO higher than 160 has an unfortunate side-effect on the M8: it shifts the image values by 1-bit for each doubling of the ISO. The M9 and M Monochrom do not do this. Looking at the values stored in the RAW file in Hexadecimal- it makes sense. Too bad it cannot be disabled. The DNG-8 compression scheme loses more values at the left end of the histogram, and shifting the data to the right is an attempt to optimize the actual values stored. For our High-ISO processing algorithm, we want all of the bits."

Edited by Lenshacker
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Does negative exposure compensation work in Manual exposure mode, with a manually selected ISO? I've never tried that!

 

That's what I was doing yesterday- had to convince myself that it was working. I got the reading in Auto mode, then manually selected the indicated shutter speed and "got the dot". Moved the shutter speed up from that spot.

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That's what I was doing yesterday- had to convince myself that it was working. I got the reading in Auto mode, then manually selected the indicated shutter speed and "got the dot". Moved the shutter speed up from that spot.

I've just re-read the entire thread and think I get it finally! Can't wait to get home this evening and give it a try. I'll post my results. Bear with me!

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Very dark yet the hat casts a well-defined shadow and his pupils are contracted ?:confused:

Following my own instructions, all now with screen shots...

 

Original-

 

16236974569_9a5395fcd7_o.jpgCloseup_original

 

LR to CS2 auto-levels, then some slight adjustment in curves.

 

16397235006_b9a3bcbd5e_o.jpgcloseup_boosted

 

Shutter set to 1/90th, was very dark. This is at least 5 stops under.

 

I sent the draft to Arvid for review.

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These guys are great, every time I come back with a new lens they strike up the same pose...

 

These pictures were taken at the Marine Museum in Quantico, Virginia. A Hollywood special-effects team was brought in to make life-masks of some of the veterans that volunteered at the Museum. The mannequins were made to look like the men in their younger days. Every so often you look at a display to look up and see the man that the mannequin is based on.

 

JUST FOR COMPARISON!

 

The M Monochrom at ISO5000 with a 1936 Sonnar, wide-open at F1.5 and 1/30th:

 

15382178157_25e56f8d85_o.jpgL1003955

 

And the M8 shot shown before, shot on manual exposure as -3ev was not good enough, F1.4 and 1/60th:

 

16414555015_e1dbc751af_o.jpgautocurves_ISO5000eqv

 

I had a yellow filter on the Sonnar, which would account for the longer exposure.

 

I've posted pictures from this display on RFF, someone asked me were the re-enactment was and how cold was it. This is the "Chosin Reservoir" scene of the Korean War, and there is a tribute to David Douglas Duncan in this section of the Museum. Last visit, I took the M Monochrom with the Nikkor 5cm F1.5 and Nikkor 13.5cm F4. My lenses are from the same batch as his, each within a few SN of his. There were maybe 400 of the F1.5 lenses made in Leica mount and even less of the 13.5cm F4's.

Edited by Lenshacker
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I've been experimenting with the options for correction and black-level. The prior version of this image did not have the non-uniformity correction applied. A tribute to the sensor in the M8!

 

Following my own, revised directions.

 

16438080772_f3da4d8cb3_o.jpgsd_b00_option

 

More experimenting to be done, the uniformity can be correct better than that shown here. Compare the shadow area of the Hat near the ear. You can see the the seam of the halves of the sensor in the first version of the image almost disappears in the second version.

 

If you "click" on the image you get to my Flickr stream, the two versions of the image are adjacent. Click the Right then Left arrows to compare the two images. You will see the uniformity correction improve agreement between the two halves of the sensor.

 

If anyone wants an early version of the write-up on this procedure, PM your Email to me and I will send a PDF.

Edited by Lenshacker
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