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Messages - PhotoCat

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26
Oh, I spot meter white wall at +2 but for skin tone it is from 0-0.6 depending on the person   :)
The autoexpo module doesn't allow me to spot-meter and recompose. Manual exposure is much preferred.

Wow, u guys are amazing! ML enhanced dynamic range! Hats off to the ML team!

27
played with autoexpo again and indeed I can setup the curves to do exactly what I want but
the problem is that the auto feature cannot be turned off.  Tried expo comp as u had suggested but
it is not obvious how it can disable auto exposure.   Note that I am a spot-metering kind of a guy
and I want the face to be correctly exposed.

Another thing abt autoexpo is that ISO and shutter jump at 1-stop increment. Would prefer a jump to be 1/3 of a stop,
so that I can pick low noise ISO for jpgs such as 160, 320 & 640.
Tks!

28
+2 in spot metering is not arbitrary. It means highlight close to white but jpg not blown out yet.  :)
Thanks for the heads up and all the hard work!

29
Quote
Point the camera at a neutral subject with very little dynamic range, say an evenly lit white wall, meter for 0 on the camera meter.  That is metered for a midtone, now increase exposure until clipping.  You should get close to 3.5 stops before overexposure.

I think we are both correct Audionut :)

I use spot metering to point at the white wall and set the meter to +2. So beyond that I have tested the 5D2 to
be able to recover highlight for another 1.3 stops.  2+1.3=3.3 stops (very close to your 3.5 stop depending upon subjective opinions)

With Magic Lantern, for portrait shooting at least, I find that I can get very accurate in-camera jpgs which significantly reduce post-processing time
by using the following metering technique:

1) False color to ensure face expose
2) RGB spot meter to ensure correct skin tone

Although I shoot raw+jpg, I believe in getting it right inside the camera to reduce post-processing time. (raw is for insurance only)

So if ML can get a raw-based jpg file and jpg preview when shooting ETTR, further raw processing in computer will not be needed, which not only saves time,
but it also makes the model happy when viewing the camera LCD as we shoot :)   
 
In summary, I think a raw-based in-camera jpg preview/jpg generation will very much facilitate the use of ETTR technique.  Tks!


30
oic. Is it possible to start from raw file in camera then like DPP with a negative exposure bias and picture style applied? tks!

31
Tks for the insight A1ex.  Looks like you have started from the raw file too to perform the darkening.
Not sure how DPP does it then (within limits).  Tks agn!

32
Added benefit is that in-camera generated jpg will have correct exposure and all the histogram and false color
work as usual. No need to do further raw processing.

33
Tks Audionut. Using your method, it is indeed darkening the image but the color is not quite right.
(seems like the darkened preview has been desaturated)
Just wondering what darkening algorithm is used?
Would be nice to produce the color in LCD preview as if the raw file went into DPP and dial down in exposure with picture style applied.

BTW, I realize there is a different overexpo limit for each camera such that blown highlight can be recovered.
My 5D2 at ISO100 is about 1.3 stops. 

BTW, is it possible to add an exposure lock on the LCD image darkening?  e.g. always dial down the exposure by 1 stop
for all playback etc. This way, one can shoot and preview studio pics as usual - all color is preserved during LCD preview
and jpg generation and at the same time performing ETTR.

I guess may we call this "transparent ETTR" ?  You turn on "transparent ETTR" but you shoot and preview as usual except you
need a little more exposure, knowing that shadow noise will be improved.

Thanks a lot!

34
Shot portraits with raw with ETTR. It is understood that the jpeg preview will be overexposed. Is it possible
to darken the jpg and jpg preview with ML automatically? e.g. if 1 stop over-exposed in raw, then apply 1 stop darkening
to the preview jpg. (this darkening level can be adjusted manually too, if need be, as the photographer knows how much overexpo there is in studio
with the incident light meter)
This will keep the model happy during the shoot and at the same time details in the dark clothing can be preserved too.
Moreover, camera jpg can be used directly without raw processing off camera. Thanks!

35
mm... autoETTR seems to be doing something very close... changing ISO and shutter speed but it has to go into live view
to do its things for a few seconds which takes time.  Full viewfinder shooting is what I need.  Also autoETTR will naturally overexpo jpegs and I will need
extra time to post-process raw files to darken the images to its normal range. I think manual exposure with spot metering works best for me for portrait shooting. Tks!

On the other hand, Autoexpo module is actually quite close to what I need as I can program the ISO and Shutter according to the metered level but unfortunately it is fully auto. Works well for landscape or still subjects perhaps depending on the metering used. For portraits, one really needs spot metering on the face.

It would be nice to be able
to turn off the "auto" part of the Autoexpo module but keep the "table-lookup" part.  Just give us a manual dial to sweep from left to right of the lookup table (curve).
Then we will spot meter ourselves manually.
That should do it.  I have a 5D2 BTW.

Thanks!

36
Quote
Quote
PhotCat:
With a fixed F-stop, the goal is to keep shutter speed at or faster than 1/320S (or another chosen value)
under all lighting levels.


dmilligan:
AutoETTR in M mode with slowest shutter = 1/320 does exactly this.

You could also play with the autoexpo module, I've never used it, but I think it lets you build a sort of custom P mode, where you define which exposure parameters to change as overall exposure changes.

Thanks dmilligan once again. Let me try autoETTR in M mode. I hv played with that b4 but it didn't seem to change ISO automatically but I will try it again.
I have also played with autoexpo module but it is auto only so it is hard to do spot metering on the face then recompose unless there is a button to lock
exposure. Even then it would not be convenient because I fine tune exposure almost from shot to shot based on false color reading on the face.
So I really need manual exposure.

37
Quote
I don't really understand the usefulness.  You have a crux point where you shift from changing shutter to changing ISO, so you still only have to play with one dial.
The complication occurs when the correct ambient exposure is around f2.2, ISO100, 1/400 when u r under a shade. Suddenly the sun goes into the cloud
then u will have to up the ISO to say 320 as well as lower the shutter to 1/320 to compensate. A 2-dial operation. 
(U don't want to keep the shutter at 1/400 and up the iso to 400
because you want to maintain a low ISO with the best noise performance.)
Then all of a sudden, the sun comes out of the cloud again and you will have to lower the ISO back to 100 and up the shutter back to 1/400 to compensate.
Another 2-dial operation.
On a partially cloudy day, this happened to me more than often and I had to constantly play with 2-dials when the sun goes in and out of the cloud.
After a while, you get tired of it and wish that ML could do something to help :)     Thanks for your attention Audionut!

38
Oh... My apology... I wouldn't say it is already done...  The expo lock method is
very different from my proposal of a single dial to roll through different exposures:

Let me make the table more clear.
As you turn the dial clockwise for example, the camera setting will change according
to the following table from left to right:  (note the exposure is increasing from left to right)


f fixed at e.g. 2.2
ISO       100   100 100 100 100 100 125 160 200 250 320 400 500 640 800
Shutter  1000 800 640 500 400 320 320 320 320 320 320 320 320 320 320

With a fixed F-stop, the goal is to keep shutter speed at or faster than 1/320S (or another chosen value)
under all lighting levels.

One dial operation would be the ultimate solution for my feature request.

UI would be like:

set f stop and set min shutter speed in M mode then turn on this new feature on ML.
Roll the dial and the setting will be changed from left to right according to the table. (from low exposure to high exposure)
Then I have to select the best exposure by reading the meter or histogram. It is still manual exposure but I only need to
play with 1 dial instead of 2 dials to change exposures. The manual operation will be much faster.  Hope it is more clear now. Thanks for helping out!

39
Thanks dmilligan for the teaching! That's vy interesting and now I know how this ML exposure lock works!
Although it is not the same thing I had asked for, it is very cool and I think I may be able to work with it.
Will test out this method in comparison to full M mode with Av, Tv & ISO
adjusted independently. 

40
Feature Requests / Re: Fast way to trade ISO for Shutter Speed - Manual Mode
« on: September 16, 2014, 07:08:41 PM »
Tks dmilligan for the info but I am not sure I fully understand how the expo lock works.

I cannot lock exposures because I need to keep compensating for ambient fluctuations manually.
What I need is a convenient way of changing ISO and shutter speed at the same time to adjust overall exposure.

41
Hello ML team:

Can the following adjustments be made more convenient?

1) Shooting in M mode and fixing aperture to f2.2 (selectable)
2) Need to keep shutter speed at or over e.g. 1/320S (selectable)
3) Use ISO to obtain proper exposure.

Right now doing it manually:

In M mode, when ambient is bright, I keep f at 2.2, ISO to 100 and set shutter to a value
to obtain proper exposure. (this value is usually faster than 1/320 for bright ambient)

When ambient level has come down, ISO 100 cannot sustain a shutter speed 1/320 or faster.
Then I will have to up the ISO to 160 or 320 or 640 to compensate, keeping the shutter speed to
at least 1/320.

Is it possible for ML to give me a single dial to achieve this shutter speed/ISO  trade off?

e.g. as you rotate the dial, the settings will change e.g. as follows (from left to right, from bright to dark)

f stays at a fixed value e.g. 2.2
ISO            ...100    100     100... 100    160     160    320    320     640    640...
Shutter ...1/2000 1/1000 1/500... 1/320 1/400 1/320  1/400 1/320 1/400 1/320...


Note I am not asking for auto exposure. I will use the built-in meter and histogram to determine proper
exposure. I just need an convenient way to trade ISO for shutter speed.

This would be very handy when shooting outdoor portraits when the sun comes in and out of the cloud
frequently. BTW, ISO 160, 320 & 640 were selected because of better noise performance in jpg.

Thanks!



42
Feature Requests / Re: Digic Peaking - Edge Image Toggle Button
« on: April 25, 2014, 09:26:42 PM »
Is the following GUI possible?

In the Digic Peaking manual, add an option "Slightly sharper/Edge Image"


i.e.

OFF
Slightly sharper
Edge Image
Edge + Chroma
Slightly sharper/Edge Image

In this last mode, the half press of shutter will toggle between Slightly sharper/Edge Image.

Tks!

43
Feature Requests / Re: Digic Peaking - Edge Image Toggle Button
« on: April 25, 2014, 09:16:48 PM »
I have a feature request or modification.

In ML menu, Digic Peaking, You can scroll from Slightly sharper to Edge Image, Slightly sharper is awesome, but still at times I am in doubt and that's when Edge Image is perfect. Is it possible that AF ON button or Zoom Out or half shutter press (or any other) could be used for quick toggling ON and OFF for Edge image? It would help a lot as a safety margin when setting focus and it would be nice if there was a quicker way to activate Edge image without going in to ML menu and scroll.

Or maybe users could choose under the Digic peaking, if they want to activate a/the shortcut button for Edge Image.

Think this would be great for all cameras.

I am on 5D MK II and on this camera it does not seem to be a problem using one of those buttons for this as they all have the same feature in RAW. Giving colour preview when ML Preview is ON. I don't know about the buttons on the other models though.


Actually everything maybe there already... I think... 

Now when in "Edge image" display, everything is dark except the edges. Holding half press of the shutter
will make the LV normal looking again.     How about reversing the polarity Marsu42?

i.e.  Everything looks normal in LV as usual.    A half press on shutter will activate "Edge Image".
Then we fine tune the focus quickly and release the shutter.  Done!

Perhaps it is just a quick polarity change in the code??   Is it possible Marsu42?  Tks!

44
Feature Requests / Re: Digic Peaking - Edge Image Toggle Button
« on: April 25, 2014, 08:33:42 PM »
Like a lot of other feature requests, this is basically linking ml features to buttons. I'm currently writing a module for arrow/set keys and can later on add ml features people want linked there, though don't expect it to be released tomorrow...

This is great Marsu42! This module would be handy to toggle between DISP 0/1/2/3  Overlays, using a right-hand-side hotkey! 
Currently the INFO key is not in the best position to toggle it, since the left hand will need to leave the lens focus ring!

45
It is perfect as it is now!  I am just a bit greedy in wishing that
the hotkey can be on the camera right as well (5D2).

This will keep my left hand on the focus ring and my right hand to
perform toggling and exposure adj, during live shooting.

Can the AF-ON button or anything on the right be used as toggle hotkey as well on 5D2?

Thanks a lot Alex!

46
Wow, A1ex, u r the best of the best! This feature is amazing & ML rocks! Thanks a lot!   :)

47
My apology if this feature exists already. I have done searches in ML & google already but I can't find anything on it.

In manual live view video recording, I find myself having to switch between focus peaking and false color a lot
for every new scene to nail down on focus and exposure. If we have a hotkey to toggle between each
active overlap (without going into ML manual), it would be very handy.  (just toggling on/off falsecolor is helpful enough)

Thanks the ML team for the great job!  :)

48
Oh... I think I may have got it now. We need to somehow program the digital multiplier into the raw file in question
so that the Canon engine can pick it up and convert the raw file into a jpg file in camera.

49
not sure if I follow u Alex but I guess my assumption of zero digital gain at ISO 1600 or at multiple of 100 is wrong then...

50
Wow, thanks Alex for the quick reply!

So for older cameras like 5D2, we should be shooting at ISO 100 multiples to have the highest quality raw file,
if I understand correctly.

Just wondering if it is possible, when shooting at say ISO 1600, to meter/evaluate (false color etc) at EC + 1/3 stop
such that we are shooting ETTR by +1/3 stop and have ML generate a pulled version (by -1/3EV) of the jpg file.
This way, we will hopefully have *Both* a good raw file and a "cleaner" jpg file at the same time in camera,
without any further post processing.

Please keep up with the great work!

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