master2be1 / 400plus

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1/8000s #278

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago
I am not sure whether this is possible at all, but I was wondering whether 
there will be a chance to give an option of the 1/8000s while shooting. I know 
that the 40D is able to produce this time. Is it physically/software-wise 
possible to make it available for 400D as well?

Original issue reported on code.google.com by doffact...@gmail.com on 17 Aug 2012 at 9:48

GoogleCodeExporter commented 9 years ago
It seems that it is software possible, since there are strings in the FW.
It looks like guiUtil_sub_FF83B9DC() routine has many switch-cases and 3 of 
them are responsible for limiting the camera to 1/4000s.
This means that it may be possible to unlock the 1/8000s though the limitation 
is hardcoded, but I'm not sure it is physically possible for the camera.

This will have to wait for now, but thanks for the request.

Original comment by fired...@gmail.com on 17 Aug 2012 at 11:15

GoogleCodeExporter commented 9 years ago
Hmmm, you just made me more curious :) Would be very interesting to know 
whether it is possible. It will be, IMHO, a major boost for this camera.

Thanks for the info!

Original comment by doffact...@gmail.com on 17 Aug 2012 at 12:02

GoogleCodeExporter commented 9 years ago
We know how to ask the camera to use a certain speed, the question is if the 
camera will honor our request. From the info provided above, there seems to be 
some hope that it will. On the other hand, we must remember that we are dealing 
with hardware here, and we could break the shutter (if I recall correctly, this 
is exactly what happened to the CHDK people).

Preparing a test is not complex at all, but I will not be the one who runs it...

Original comment by eduardo....@gmail.com on 17 Aug 2012 at 12:15

GoogleCodeExporter commented 9 years ago
Yes, I am 100% aware of the dangers. My interest is exactly in this, if this is 
possible to make it in the firmware, how would react the shutter and its 
hardware. Do you have it confirmed that the 400D on shorter speeds than 1/4000s 
broke their shutters?

I do not have to explain you what would it mean to shoot for example at ISO100 
@ 1/4000s and you have to use f/4 or f/3.6, instead of f/1.8 or lower ... which 
you can achieve with 1/8000s ;)

Original comment by doffact...@gmail.com on 17 Aug 2012 at 12:22

GoogleCodeExporter commented 9 years ago
Here is a pseudo code from what I saw in the firmware:

IF (speed < 30s) {
    do something
} ELSE IF (SPEED < 1s) {
    do else
} ELSE IF (.....) {
    ....
} ELSE IF (speed < 1_4000) {
    goto 1_4000;
} ELSE {
    goto 1_4000;
}

so it is software blocked, it wont do 1/8000 unless we rewrite these routines 
to unlock the shutter speed...

about the physical possibilities - I believe the camera will do 1/8000 and the 
restriction is just like the others restrictions that should make you buy a 
higher-end camera.

though, it would be great if we have a spare camera (even broken in some way) 
just to test these dangerous scenarios...

in that matter of speaking: 
http://www.magiclantern.fm/whats-new/78-news/133-defective-cameras

Original comment by fired...@gmail.com on 17 Aug 2012 at 7:19

GoogleCodeExporter commented 9 years ago
Ok, what you are talking about is exactly my suspicions, that the 400D is just 
blocked with a software but maybe (?) it is possible to have the 1/8000s.

The question is then whether there is any camera available to try it out? Does 
anybody have a spare 400D? :)

Original comment by doffact...@gmail.com on 18 Aug 2012 at 10:54

GoogleCodeExporter commented 9 years ago
I would be willing to test this on one of my cameras. I have 2 and one of them 
is in pretty bad condition anyway. (lots of dead pixels, partly melted exposure 
sensor)

Original comment by purest...@gmail.com on 25 Aug 2012 at 5:50

GoogleCodeExporter commented 9 years ago
Great! I'll prepare a test binary as soon as I return home.

Original comment by eduardo....@gmail.com on 27 Aug 2012 at 10:21

GoogleCodeExporter commented 9 years ago
cool - I'm ready to test as soon as I get the file...

Original comment by purest...@gmail.com on 30 Aug 2012 at 9:43

GoogleCodeExporter commented 9 years ago
Guys, this is great! I am looking forward for the test results. Fingers 
crossed...

Original comment by doffact...@gmail.com on 31 Aug 2012 at 6:07

GoogleCodeExporter commented 9 years ago
Here it is!

Copy attached file to card, set camera to M mode, and launch the intervalometer 
script. This will fire the test code; it will take 9 shots, starting with the 
selected shutter speed, and increasing it (shorter exposure time) 1/8 EV each 
time down to EV-1. It seems to work for "normal" exposure times; if camera is 
set to 1/4000s, it should go down to 1/8000s (I did not try it myself).

On the other hand, this test closes issue 33: even if the script tries to use 
all eight intermediate shutter speeds, the camera only uses a restricted set of 
different exposure times.

Original comment by eduardo....@gmail.com on 6 Sep 2012 at 1:10

Attachments:

GoogleCodeExporter commented 9 years ago
hmmm, I tried launching the intervalometer script, it just takes a photo every 
2 sec's all the same exposure. - maybe I'm missing something... I will try 
again this afternoon when I have more time.

Original comment by purest...@gmail.com on 8 Sep 2012 at 9:04

GoogleCodeExporter commented 9 years ago
Sorry, my mistake: try the EAEB script, not the intervalometer.

Original comment by eduardo....@gmail.com on 8 Sep 2012 at 9:07

GoogleCodeExporter commented 9 years ago
ok, I ran the EAEB script, 
with shutter setting at 1/4000. it took 9 photos, all with shutter time still 
at 1/4000, and looking at the photos they all seem to be exposed equally.

Original comment by purest...@gmail.com on 8 Sep 2012 at 12:52

GoogleCodeExporter commented 9 years ago
That's bad news... This means we need to hack into the part of the code that 
controls the shutter; and that is way out of what I can currently do.

Original comment by eduardo....@gmail.com on 8 Sep 2012 at 1:10

GoogleCodeExporter commented 9 years ago
Hi Eduardo (all). Why is it way out of what you can do? Is it impossible, or 
just hard to achieve (so there is still some hope)? :P

Original comment by doffact...@gmail.com on 8 Sep 2012 at 1:32

GoogleCodeExporter commented 9 years ago
> Hi Eduardo (all). Why is it way out of what you can do? Is it impossible, or 
just hard to achieve (so there is still some hope)? :P

Right now, most features implemented by 400plus rely on politely asking the 
firmware to do nice things, and then the firmware talks to the hardware; this 
is how we achieved spot metering, AF patterns, custom color temperature, ...

The file attached on comment 11 asks the firmware to use a shutter of 1/8000, 
but it refused to acknowledge the request, and simply shot at 1/4000. So we 
would need to dig deeper in the firmware, see how it takes a photograph, and 
try to find a method to interfere in that process.

Being realistic, I think it is safe to assume that this feature is impossible 
to achieve.

Original comment by eduardo....@gmail.com on 20 Feb 2013 at 8:13

GoogleCodeExporter commented 9 years ago
Actually the speed is sent to the MPU and it controls the shutter(curtains) 
itself.
So, I believe we wont be able to achieve anything more than 1/4000.
The MPU would not do this.

Original comment by fired...@gmail.com on 20 Feb 2013 at 12:43