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I would expect the dual-ISO shot to be a touch better.  Because you clearly haven't ETTR the lower ISO and the higher ISO will now be ETTR.  Of course, you could have just ETTR the low ISO and called it a day

Thanks for your patience on providing a number of clarifications.

Based on what you've written, there doesn't seem to be much, if any, downside to having Dual-ISO enabled all the time. With static images, you'd take the time to get ETTR at a good setting.

If I understand what you've written, with a low to moderate contrast scene (as evidenced by fitting within the histogram), most or all of the information would come from the low ISO part of the exposure. The high ISO info wouldn't apply.

But when you did need the expanded DR of Dual-ISO, it would be there.

Somehow, I think that conclusion reflects a simplistic understanding on my part.

And to me, a more complicated and slower workflow is a liability (not a limitation, as you point out).

Some geek speculation:
The impression I have is that during the actual exposure, a ML routine is invoked that examines a pair (or quadruple?) of scan lines. In real time during the exposure, it is deciding whether to used just the low ISO pixels, or to merge the high and low ISO info.  It almost seems like that would be on a pixel by pixel basis.

But I have my doubts that is really going on.

Also, I'm unclear how "aliasing" comes into it? Do you have a situation were two (or four?) pixels are averaged and/or interpolated? I observe that the thumbnails have a huge amount of moiré, but that's gone after cr2hdr.exe works its magic.

But I guess I don't have to understand how it works to be able to use. Whew.

In a nut shell, adjusting the image in post.  Exposure, contrast, highlights, shadows, saturation, etc, etc.

So, the "Auto Grading Script" seems like it might be a smarter "Auto button" than ACR and LR have? Or more flexible with more user control?

Exactly.  Unfortunately, dual-ISO doesn't come for free.  It has limitations that must be considered.

I wonder if my list of limitations is correct: complicates and slows down workflow, some loss of resolution .... others?

There are 2 exposures with dual-ISO.

Now that's different from my newbie understanding. I had thought that during a single exposure, different scan lines of sensor pixels had different tone curve characteristics (i.e., ISO).

Are there two actual exposures? Is the sensor turned on and back off twice? I suppose that happens quite quickly, but with a moving target, could you get some ghosting? For a 5d2 with Digic-4, any idea of the time delay between the exposures?

Where both ISOs capture detail, full resolution is retained.  Where only the lower ISO captures highlight detail (higher ISO becomes overexposed), then you suffer reduced resolution (aliasing).

I recall the original post describing Dual-ISO mentioned resolution loss, but I thought it was more straightforward than what you describe.  Your explanation fills in some gaps.

So .... if you had Dual-ISO enabled with a relatively low contrast scene with no blown highlights and no blocked shadows, then the "ON" and "OFF" files would be very, very similar? Little or no loss of resolution?

Thanks for the input. Whew. It seems like I am not too far off.

It also depends heavily on how are you going to color grade your pictures

I've seen "color grade" mentioned, but I am ignorant about what that means. I did find the post on "Auto Color Grading", but it was mostly over my head. Also, it seemed dependent on quite a few tools that I'm unfamiliar with.

Is this a valid summary: gets all pictures "in the ballpark" as a starting point.

I'm unclear on how to use Dual-ISO to best advantage. I think I may be close to a good workflow, but I wanted to check for sure, and also learn about "the error of my ways" from others on this forum with more experience and expertise.

• Appropriate for scene with high contrast, where HDR would help.
• Even with RAW histogram, there is "valuable content" on the left and/or right side.
• Otherwise, "why bother?" if the levels fit within the histogram ok (low to moderate contrast)
• For an example using ISO 100/1600:
• Dual-ISO starts at OFF
• (but does Auto-ETTR take Dual-ISO into account, so this isn't necessary or appropriate?)
• Or does the camera's normal metering end up being appropriate?
• Determine best exposure for bright areas at ISO 100, perhaps with ETTR, trial-n-error, etc.
• ...
• The RAW histogram would tend to look like it was ETTL (exposed to the LEFT)
• Exposure will tend to be underexposed, with few if any blown highlights, but will probably appear to have "blocked shadows" on the LCD.
• Enable Dual-ISO (this example uses 100/1600)
• Take picture(s)
• Process with cr2hdr.exe
• Open with ACR, LR, or other
• Expect to see an image that looks rather underexposed
• Image should have quite a bit more usable dynamic range, so the exposure/shadows/blacks can be increased significantly without as much noise happening

Or not?

Am I "unclear on the concept"? Do I have a flawed understanding of how Dual-ISO is supposed to work?

Is my workflow more or less ok, but sub-optimal? Would a different technique work better? Am I leaving something out? I haven't really been following the progress on ETTR and Auto-ETTR, but my guess is that those capabilities are now somewhat integrated.

My speculation is that once you "get the hang of it", you don't have to disable Dual-ISO, but can more go by the metering and/or Auto-ETTR.

Sorry in advance if this post comes across as whining and/or unappreciative and/or grumbling. I am a HUGE FAN of ML.

I started watching the video, and was impressed that it was available, and the production qualities were fine.

• Like the OP, I also would like something like an "elevator pitch" to provide to people.  I'll be gushing about ML to people I encounter in local camera clubs, and it would be great to give them a TinyURL for them to check out further.
• Often, "a picture is worth a thousand words", but not necessarily a video of someone doing a power-point presentation (aka "talking head")
• Gosh, it was 42 minutes long. I say this to my shame, but I gave up after 3 minutes. Perhaps later in the presentation it became something other than a "talking head" video, but I'm too busy/lazy at the moment to watch the whole thing.
• I kept thinking ... "darn, if there was a transcript of the presentation, along with the slides, I could probably get the gist of the presentation in five minutes or less".
• Again, sorry for the grumbling.

I actually liked the procedure in which the 2.3 was released. First let the supporters have a go for a month, then a well produced trailer and to finish it:

Agree.

call it version 3. IMO too many things have changed since 2.3 to call it 2.4.

Very much agree. The 2.3 documentation is almost too "stale" to be useful. There have been absolutely amazing improvements since 2.3.

I'm more of a "casual user" of ML ... perhaps install a latest/greatest "nightly build" every other week or so. I'm regularly baffled by what is new, and how to get it to work. Amazing features show up in the Menu, but it's unclear to me what they do, and what is "best practice".

Also, what might be risky to explore? That troubles me, and makes me reluctant to stray from what I feel I understand, or to help with testing.

Sorry for the whining. I am a HUGE FAN of ML. I try to look at the "change log", and the "Feature Requests", but I'm still often fuzzy on the "best practices".

I'm not able to tell you exactly what it is, but:

Perhaps it is related to "cookies" not being enabled?

This forum, among many others, utilize the databases from http://www.stopforumspam.com/ in order to validate that you aren't a spammer. Use the search function in order to check if you email addresses or usernames are listed.

Interesting. I took a look at that website, but I'm unclear how this works. Is it an automatic process, or does a ML moderator have to manually check if a new "person?" seeking membership is on the stopforumspam list?

The reason I ask: I am the admin at another SMF forum, and have been cursed with malicious spam at other website that I am webmaster:
www.CanPrint.org (more or less under construction ... want to open up to active use once I get it more secure from spam)

I rarely notice spam on ML, so I infer that ML has some SMF security mods installed, or very effective and hard working moderators.

I've got an "under construction" website
www.CanPrint.org
that also uses SMF as the forum engine.

The "point" of CanPrint.org is to help people get proficient with inkjet printing, specifically using Canon printers. It is a non-commercial website, and not ad supported.

I've been impressed by how well ML controls spam. I rarely if ever see inappropriate posts. I was hoping to find out how that is accomplished, and make adjustments as appropriate to my website.

• Does ML have security "mods" to reduce spam?
• Or does ML reply on moderators to identify and remove spam?
• How is ML able to restrict malicious bots from gaining membership and posting spam?

See:
Discussion on how to "double and triple stack" discounts to get best price.
http://www.dpreview.com/forums/post/52615444

Canon link (best link for best deal can vary ... state of flux during Black Friday)
http://shop.usa.canon.com/shop/en/catalog/buy-one-get-four-free-when-you-buy-select-canon-photo-paper?cm_sp=SP-_-PRT-_-Text_BFbuy1get4
http://shop.usa.canon.com/shop/en/catalog/free-gift-paper-and-scrapbooking-kit-promo

If you figure out how to play the game, you can legally and ethically get well over $200 USD worth of premium Canon paper for under $20, directly from Canon. About 7¢ per letter size sheet on Luster, Semi-Gloss, and Plus-Glossy II. The MSRP is 70¢ per sheet. The Pro Platinum is about 13¢. 4x6" glossy for about 2¢

50% off with triple stacked discount of "Buy One Get Five" plus "50% off for registering your Canon printer" and also "Nine free gifts if order over $50". And free shipping. There will be local tax on the net amount. No rebates to fuss with or forget.

Some days there is a promotion for 13x19" A3+ paper, and some days not. About 19¢ per sheet, if I did the math correctly (100 sheets for $18.50 USD ... that's pretty easy).

Note that for actual low costs per print, you pretty much have to refill your cartridges with non-oem ink. Otherwise, you are still paying about $10,000 per gallon for Canon oem ink. There is a significant learning curve to cart refilling, and upfront expenses. It's only rarely that I've seen real discounts on real Canon oem ink. The ink is the "crown jewels" for Canon (and Epson and HP are even higher per gallon).

My go-to paper for give-away prints used to be Costco Kirkland at about 15¢ per sheet. For what I do, Canon oem paper was too expensive at about 70¢ per letter size sheet (MSRP).

My speculation is there are more than a few people on this forum with Canon DSLR's and Pro-100 printers. The cost of ink and paper will eat you alive without super discounts, unless you are a professional printer and the cost of ink + paper is a small percent of the selling cost.

FWIW: with cartridge refills using non-oem German ink and super discounted Canon paper, I can now make high quality, color managed letter size prints for under 10¢ a sheet. Giving away 100 letter size prints as a volunteer photographer at a non-profit event is now chump change.

DPReview.com had an announcement that owners of EOS C100 video cameras can get their device upgraded to have DPAF, for $500. Apparently, the sensor had the capability all along, but the firmware didn't support it at time of release.
http://www.dpreview.com/news/2013/11/06/canon-offers-dual-pixel-af-upgrade-for-cinema-eos-c100-camera

Any chance this might apply to the 5d3 or 6D? Seems at least remotely possible that their sensors might actually have dual-pixels, but not enabled in firmware.

Or not?

That would really be a great feature for all of us crazies w/ a bunch of vintage M42 glass :-)

Also very handy for owners of Samyang fully manual lenses. I can use ExifTool after-the-fact to change the EXIF, but I have to remember just what the f-stop was, which is error prone.

I have a profile for the Samyang 14mm f.28, so it makes a difference in ACR/LR on corrections applied by f-stop, including vignette.

According to the changelog, the latest IQ updates were in late August:

https://bitbucket.org/hudson/magic-lantern/commits/all?search=cr2hdr

I'm fuzzy on what the comments for the latest/greatest cr2hdr.exe from Oct 11, 2013 mean, but they do seem to indicate that this version could result in .dng's with better IQ compared to using previous versions of cr2hdr.exe.

Or not?

Made good progress yesterday, and it looks like the 5d2 is ok. Whew.

I was able to purchase an aftermarket non-oem battery from a local camera store, and it seems to be working more or less fine. Whew. I'll monitor it closely for the next several weeks.

Pricey and rather underpowered compared to on-line deals, but I suppose worth it ($50 and only 1820 mAh compared to others online with ~2600 mAh ... although those may be inflated).

Once fully recharged, the 5d2 seems to consistently boot. The 5d2 won't consistently boot from the original LP-E6 that came with the camera (now 3.5+ years old) or another non-oem LP-E6 I got several years ago for cold night shooting.

Another issue that may very well have contributed was that my main 16gb CF card may have gotten corrupted. Even before getting the new battery, I was able to more often (less intermittent) boot with several older 4gb CF cards with and without ML.  Puzzling.

I did format the 16gb card on my PC with a card-reader, which I don't recall helping. Then I reformatted the 16gb card with an older 50D that also uses CF cards. That seemed to help.

Now the 5d2 generally boots with the 16gb card with the latest NB installed. It does seem more prone to wanting the battery removed and put back in.

I will definitely be more careful to not remove the CF card until 5+ seconds after powering down. It does seem possible that I wasn't doing that consistently in the past. That may have stressed the older batteries that were near end-of-life, and pushed them over the edge. My bad?

My speculation is that it MIGHT be possible to do something like ML to Canon printers. Feasible?

I'm aware that Canon publishes an API for interacting with [fill-in-the-blank]. Is this mostly related to their software, like DPP? Or does it provide any kind of baseline toolkit for interacting with cameras? Printers?

I think the Canon printers I'm familiar with allow firmware updates. IIRC, I don't know if I've every actually done that. My understanding is that the recent Pro-100 has had several firmware updates.

Specifically, I'd be interested in enhancing some of the diagnostics that Canon printers can do. Thinks like:

• Put a timestamp on nozzle checks, alignments, etc.
• Including other information on nozzle checks, alignments, etc. ... such as printer serial number and print-head serial number
• Enhance nozzle check to print out the "slanted diagonal grid" for all cartridges and nozzle sizes, similar to what is done for the pigment black ink (which is very helpful to see exactly if a specific nozzle is clogged ... but could be hard to see with yellow and PM, PC, etc.)
• Print out pure large rectangles like the nozzle check, but at "full color" purity and intensity, rather than diminished intensity like the nozzle check. Would include the different nozzle sizes, like 5 picoliter, 2 pl, 1 pl, depending on the printer model
• Eventually accomplish something like a RIP for specialized b/w printing
• "Stress tests" that really challenge ink flow, much more challenging than nozzle check
• Intelligently "defeat" the ink level monitoring so perhaps cartridge chip resetters would be less necessary, or unnecessary
• lots more, but the above may give a sense of possibilities

Thanks for using ExifTool to show this ExifTool newbie that the Exif information I was interested in was actually preserved in the .dng.

I used the command line
ExifTool MyDngFromDngConverter.dng -All
to see what was available from a .dng that was generated by DngConverter from a .cr2

The source of my confusion / error is that Adobe's Bridge doesn't seem to make those specific Exif fields visible.

Within Bridge + Edit + Preferences + Metadata, they aren't in the list of Metadata that can be check-boxed to appear for a selected image.

Thanks for the follow-up.

My inference is that you are referring to the Install.pdf for the 2.3 stable release:

Code Select Expand

After opening the card door, always wait for LED confirmation (or for 5 seconds) before
removing the card!!! During that period, Canon firmware accesses the card without
turning on the LED, and if you remove the card too early, the camera will freeze and
will drain the battery. Exception: 550D users don't have to wait.

It's possible that has happened in the past. I do recall once that I was surprised the battery was unexpectedly drained, but that was at least a month or so ago. Generally, my "work-flow" of getting files from the CF card onto the computer avoids the problem mentioned. I try to be pretty organized and methodical about going from one photo session to another.

As far as this morning, my recollection is the camera was working fine the day before for several hundred pictures. I'd copied the .cr2's onto the computer, and started post-processing. The battery went to the charger as soon as I got back home. My practice is to not format the card until just before another photo session, to minimize the chance of neglecting to get images off the camera.

IIRC, I put the freshly charged battery (Full Green) from the charger to the camera this morning, and headed outside to the park 4 doors away. Usually, I do a last sanity check to turn it ON to see if the camera is alive, but didn't do that until I got to the location for the star-trails. That's when I noticed it was Dead ... unable to turn on. Fortunately, I was only a short walk away from my backup T3i.

My point is that I don't think your (much appreciated) suggestion applies. The battery was fully charged. When I got back to the house and put it in the charger, it flashed several times, and then the charger showed Solid Green, indicated Fully charged. So I don't think it had been drained.

Again, I have my doubts that this is ML related. At this point, I'm trying to do the best job of trouble-shooting so I don't have to sent it in for extended warranty work. I dread getting it back with "it worked fine for us". Or "repair-under-warranty-declined" because of [fill-in-the-blank].

If anything, I speculate it is the ON-OFF switch, the battery contact, or the power supply. My next step is to a local camera shop that may be willing to try a "known-to-be-good" LP-E6 in the camera.

Summary:

• I've got a Canon 5d2 that I originally purchased in May, 2010 that may be developing problems.
• Wouldn't turn ON this morning.
• No lights or LCD activity when on/off lever moved from OFF to PART-ON or FULL ON.
• Intermittent ... sometimes LCD will come on when CF card isn't installed ... every tenth time or so?
• My uninformed speculation is that this isn't related to ML, but the behavior is possibly similar to bricked camera from ML.
• Plus ML gurus may have a LOT of experience with mis-behaving cameras that act "bricked".
• At this point, appreciate guidance on how to troubleshoot, and how to proceed with Mack extended warranty to maximize odds of having repair covered rather than declined.
• Some concern that if I send it in for warranty work (extended), it will intermittently work fine once received by Canon / Mack extended warrant. It'll come back with same problem(s).
• "What's changed?" Nothing comes to mind, other than this is the first time it's been used in cool/cold weather in some time.

More info and trouble-shooting I've done so far (may be TMI and/or TL;DR  ... sorry)
What happened this morning:

• Attempting to take star-trails pre-dawn ... about 4:00 am with ~7:00 sunrise. About 34F degrees (not freezing, but chilly)
• Aftermarket (non-oem) battery (made by POWWER from Adorama or BhPhoto or from Amazon?) had been charging and was "Full Green" 100% SOC (state of charge)
• Put 5d2 in padded camera fanny-pack to let it gradually cool off about 15 minutes prior to heading to nearby park
• Once in park, put 5d2 on tripod and attempted to turn on. Nothing. Nada. No power lights or LCD activity.
• Attempted with original Canon oem LP-E6 battery that has "Recharge Performance" of "Slightly Degraded". Also nothing.
• Put camera back in padded fanny pack and brought back inside.
• Proceeded with back-up T3i/600D to take star-trails

Most of the time, neither LP-E6 battery brings camera to life ... Canon original and aftermarket made by POWWER.

• Both batteries have been working fine.
• Both charge to "Full Green" in Canon charger.
• Both show 99+% SOC (state of charge) once done with charging.
• The POWWER after-market battery show three bars for recharge performance, which user manual indicates is "Fine"
• "Recharge Performance" of the original Canon battery .. two bard (Slight degradation)
• Removed CF card, removed lens, and put on body-cap to simplify.

Been using MagicLantern (ML) latest/greatest nightly-builds for about a year or so.

• 5d2 had been working perfectly the previous day with the same ML firmware
• Swapped out CF card with another that didn't have ML firmware on it. Still dead.
• Canon may not like that camera has had ML installed. I think they can detect that some AutoBoot flag is set on the camera. Or not?
• At times, I've had ML nearly brick the 5d2 and my T3i/600D with unhappy nightly builds, but these have been resolved with some head-scratching and wrestling. May have been operator error on my part ... PEBKAC.

After an hour or so inside, the 5d2 will intermittently turn on partially

• With no CF card, and aftermarket POWWER battery, camera has come to life several times
• Only about 1/10th of the time I turn switch from OFF to ON
• Able to check "Battery Recharge Performance" and observe 3 bars (Fine) with POWWER battery
• Whew ... at first.
• But haven't been able to get ON with CF card installed ... at least at first when "boot'ing"
• After about 10+ tries, about to get ON with Canon-oem battery and no CF card.
• Two bars for "Recharge performance" using original Canon oem LP-E6 (manual indicates "Slightly Degraded")
• Once camera comes on, able to open CF door (which turns camera partially OFF ... power LED off and LCD off)
• Leave ON/OFF switch in "FULL ON" position
• Install CF card
• CF card recognized ... seems to be working ok
• After about half an hour, camera won't come back on. Acting Dead again. Drat.

About a month ago, something similar happened, but I'm fuzzy on the specifics

• POWWER after-market battery had been charging, and was "Full Green"
• Put battery back in camera. This may have been the night before or as heading out.
• Checked camera before driving away as a "last sanity check"
• Camera dead, like battery was dead (glad I checked)
• Put back in charger, and the status light flashing may have indicated nearly drained
• Used original Canon oem battery, which was fine
• Seemed like camera may have drained battery by just being in the camera overnight
• Once POWWER battery fully charged, has been fine for the past month or so ... until yesterday

Camera has been used quite a bit by a non-professional, but "serious hobby'ist"

• Utility included within ML shows about 190,000 shutter activations
• Which includes going into LiveView mode
• Canon specs indicate shutter is expected to last 150,000 shutter activations.
• Stats collected by ML indicated that "average" 5d2 goes about 350,000 shutter activations before dying. Whew.
• Camera almost never used for video
• When first acquired, somewhat ignorant about what are "best practices" for longevity
• Did some experiments with videos, and some were long and may have over-heated camera
• Mea culpa ... camera has been dropped twice since I've owned it
• about 4 feet each time onto carpet.
• both times, didn't seem to faze the camera, continued working fine
• possible some kind of "accelerometer" within the camera could detect it has been dropped
• near end of warranty, and after first drop, focus screen fell out and was fixed under warranty
• I did have to go back and worth with Canon support via email to get it covered under warranty
• Which I infer that indicated that a "has been dropped accelerometer" hadn't been triggered. Or not?

Have extended warranty from Mack camera, purchased at time of original order.

• Need to track it down ... ASAP ... and check for sure if it covers 3 years, 3 additional years, 5 years
• Mack may object if ML firmware used?
• Concern that if I send camera in for warranty work, it will behave when they test it.

Best guess? battery terminal connection or on/off switch or power supply?

My understanding is that Canon has some proprietary EXIF info embedded in their .cr2 RAW files for non-standard info like

• If Long exposure noise reduction on/off
• If High ISO speed noise reduction on/off/strength?
• If Auto Lighting Optimizer enabled/disable
• Peripheral illumination correction enabled/disable
• others, depending on model

The above (and more) is available to DPP 3.13.45 using their "Info" window. Many or most of the above don't seem to be available when Adobe's DngConverter generates .dng's from the .cr2's. Drat. Or perhaps I'm unaware on how to accomplish this?

If this Canon specific exif info is "lost" by DngConverter, is there a way for MagicLantern to accomplish this, or equivalent? Some other utility? I've asked on the ExifTool forum, but that doesn't seem like something ExifTool could do.

Could ML do something like make Keywords out of this non-standard exif info, such as what cr2hdr.exe does? Or some renaming option like what is an option with DUAL_ISO?

Ideally, this would only be needed until cr2hdr progresses to the point where keeping the original CR2s becomes pointless.

I'm wondering if cr2hdr.exe has become "stable" in the sense that newer versions don't change/improve the image quality. It becomes an issue of whether it might be worth reprocessing older .cr2's with the latest/greatest cr2hdr.exe.

Or does this not apply? Is it more or less the equivalent of Adobe coming out with an improved ProcessVersion (like 2003 -> 2010 -> 2012) which can justify converting older image files to the latest/greatest process version?

If the image quality is improving, then my speculation is that the .cr2 is the actual "master". Rather than trying to accomplish embedding the original .cr2 within the .dng, just keep the .cr2 and regenerate the .dng when a latest/greatest cr2hdr.exe is developed that actually makes a difference to image quality.

Something like a speed improvement for cr2hdr.exe wouldn't warrant reprocessing the original .cr2's to make new .dng's.

Or not? Do I have a flawed understanding of what cr2hdr.exe does?

I noticed there is a new (2013-Oct-4) cr2hdr.zip with refreshed cr2hdr.exe and dcraw.exe

I'm wondering if the changes make any different to the image quality of the resulting .dng's. If so, would it be worth using the new cr2hdr.exe to reprocess older .cr2's that used DUAL_ISO?

FWIW: My speculation is that if newer versions of cr2hdr improve image quality of DUAL_ISO images, then the original .cr2 is now the "master", and the corresponding .dng isn't really the equivalent of a "matching master".  Or not?

Would it be feasible/appropriate to somehow note or highlight that a new version of cr2hdr.exe improves image quality? Perhaps with some kind of naming convention? Or something the equivalent of PV2010 changing to PV2012? 

5d2 2013-Oct-1 Nightly Build

In dim lighting, using "Set" to get ETTR will sometimes fail with the message "Expo Limits Reached".

When that happens, the ISO has been changed to 1600, and the shutter speed to the lowest allowed (like 30 seconds). My preference would be to return the ISO and shutter speed to the previous settings.

My practice is to make my best guess at exposure, take a picture, and look at the ETTR hint based on the actual RAW histogram (which I believe doesn't use LiveView, but that actual RAW data).

I've noticed that I'll get this message when it isn't really that dim, and an EV higher than 1600 ISO and 32 seconds will work ok. I suppose this is because ETTR "Set" works with LiveView, which meters at about the equivalent of 1/30 second? Or not?

[raw]

HTP only effects JPG/H.264 data.  Turning it on for raw simply raises the minimum ISO to 200.

That's not my understanding of what HTP does, and not consistent with my observations when using HTP with raw still photos. I'm pretty sure I'm seeing a larger raw dynamic range using HTP-200 than using non-HTP with iso-100 or iso-200.

Unlike settings like WB, picture-styles, etc. that only influence .jpg's, my impression is that HTP actually results in changes in how raw values are recorded from the sensor. It changes the "tone mapping" of the sensor.

My understanding is that DUAL_ISO works best with the "base ISO" at 100, and the "recovery ISO" at 200 to 1600.

My observation is that using HTP can provide about a stop better dynamic range in normal (non-ML, non-DUAL_ISO) images.

What about using HTP (highlight tone priority) and ISO 200 as the "base"?

OK?

Flawed?

Disagree. Loss of 50% of vertical resolution in parts of the image is a very important consideration.

My "use case" tends to be panos of 180 to 360 degrees FOV. There tends to be plenty of resolution, but dynamic range is often high. I'm trying to use HDR less and less.

• 14 mm Samyang on full frame ... 4-7 frames in portrait mode results in horizontal resolution of 10k to 14k
• 8mm Samyang fisheye on full frame ... 3-5 frames in portrait mode results in horizontal resolution of 7k to 10k
• With an interior involving two rows of 7 frames when using the 14mm, an HDR becomes 42 frames.
• http://berean.zenfolio.com/uwp