SX50 HS: Where can I report a possible BUG?

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SX50 HS: Where can I report a possible BUG?
« on: 23 / February / 2014, 17:30:43 »
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Hi,

I found a link here in the forum for bug reporting that is not working anymore.

I am using CHDK_DE_sx50hs-100b-1.3.0-3351-full_BETA_rev_3351.zip in order to play with "Custom Auto ISO" in HiSpeed Burst Mode.

Usually my SX50 makes use of 800 ISO in HiSpeed Mode independent from weather/light conditions.
Even if you have a shiny day and could make pics with 1/500 and 100 ISO the SX50 simply selects 800 ISO.

With CHDK 1.3 I can overcome this problem by defining an interval of 80 - 100 ISO in combination with i.e. 1/500.


But I have two problems:

1) Th AF-FRAME cannot be moved and resized anymore. Without loading CHDK 1.3 this is possible in HiSpeed-Burst-Mode (scene).

2) My SX50 indeed makes use of the min. Shutterspeed and ISO-Values defined in "Custom Auto ISO" but I always have to work with - 1 1/3 EV to get correctly exposured shots. Without -1 EV or -1 1/3 EV all shots get overexposured with my SX50 HS in HiSpeed burst mode!

An owner of the SX230 checked out the scenario mentioned above with the SX230 and confirms that he does not need to make use of  -1 or -1 1/3 EV in Custom Auto ISO to get correctly exposured shots with i.e. 100 ISO in HiSpeed Burst Mode.


Best regards
canontestit

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Offline reyalp

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Re: SX50 HS: Where can I report a possible BUG?
« Reply #1 on: 23 / February / 2014, 18:26:08 »
1) Th AF-FRAME cannot be moved and resized anymore. Without loading CHDK 1.3 this is possible in HiSpeed-Burst-Mode (scene).
If you aren't in CHDK alt mode, CHDK shouldn't interfere with existing keys. If the function you are trying to use is on the alt key, then a long press should get you the original Canon function. However, if I have understood the sx50 manual, this AF key is not one of the alt key options.

Can you describe what happens when you try to adjust it? Can you adjust it with CHDK in other modes? Are you sure you haven't changed the canon settings to one that prevents you from adjusting the AF frame?


Quote
2) My SX50 indeed makes use of the min. Shutterspeed and ISO-Values defined in "Custom Auto ISO" but I always have to work with - 1 1/3 EV to get correctly exposured shots. Without -1 EV or -1 1/3 EV all shots get overexposured with my SX50 HS in HiSpeed burst mode!
No real idea about this one, maybe the canon firmware still thinks it's using ISO 800?

For both of these issues, it would be helpful if other SX50 owners can check.
Don't forget what the H stands for.

Re: SX50 HS: Where can I report a possible BUG?
« Reply #2 on: 23 / February / 2014, 18:32:15 »
1) Th AF-FRAME cannot be moved and resized anymore. Without loading CHDK 1.3 this is possible in HiSpeed-Burst-Mode (scene).
Strange.  Does it do this when you have a "new" CHDK install (or all parameters reverted to default using the CHDK menu CHDK Settings and menu item Reset Options to Default ...  ?


Quote
2) My SX50 indeed makes use of the min. Shutterspeed and ISO-Values defined in "Custom Auto ISO" but I always have to work with - 1 1/3 EV to get correctly exposured shots. Without -1 EV or -1 1/3 EV all shots get overexposured with my SX50 HS in HiSpeed burst mode!
From what I can tell, there is a little bug in the current AutoISO code. It does not set an Av value (f-stop).   So cameras like the SX50,  which have an adjustable iris, will use whatever value the Canon firmware wants to use. And that setting will be totally unrelated to the exposure settings the AutoISO algorithm calculates for shutter speed and ISO setting.   I can't tell for sure,  but that might be the root of your problem.

Update :  I took a look and I no longer believe there is a bug related to not setting an Av value for cameras with adjustable apertures.   At the point where the autoiso code runs,  the Av value should already be set. The code just adjusts the Tv and Sv values proportionately.
« Last Edit: 07 / March / 2014, 18:54:23 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16

Re: SX50 HS: Where can I report a possible BUG?
« Reply #3 on: 27 / February / 2014, 17:16:39 »
Hi,

here one can see a few examples.

EXIF Pic 9211: 100ISO without EV-Correction with CHDK 1.3
EXIF Bild 9212: 100ISO with EV-Correction -1 with CHDK 1.3
EXIF Bild 9214: 100ISO with EV-Correction -1 1/3 with CHDK 1.3
EXIF Bild 9216: 800 ISO without EV-Correction WITHOUT CHDK 1.3 (Regular HiSpeed-Burst Mode HQ).

Other SX50 owners confirmed the behavior in HiSpeedBurst-Mode: The SX50 alway selects high ISO values that are not necessary. So noise is produced although it would be possible to avoid it.

With CHDK you can replace the high ISO values but have to make EV corrections -1.

The last pic was shot in regular HiSpeedMode without CHDK (with automatically generated 800 ISO value).

While ISO SpeedRatings in EXIF shows up 800, AUTO ISO and BASE ISO are 200.
What does that mean?


Best regards
canontestit



1) Th AF-FRAME cannot be moved and resized anymore. Without loading CHDK 1.3 this is possible in HiSpeed-Burst-Mode (scene).
If you aren't in CHDK alt mode, CHDK shouldn't interfere with existing keys. If the function you are trying to use is on the alt key, then a long press should get you the original Canon function. However, if I have understood the sx50 manual, this AF key is not one of the alt key options.

Can you describe what happens when you try to adjust it? Can you adjust it with CHDK in other modes? Are you sure you haven't changed the canon settings to one that prevents you from adjusting the AF frame?


Quote
2) My SX50 indeed makes use of the min. Shutterspeed and ISO-Values defined in "Custom Auto ISO" but I always have to work with - 1 1/3 EV to get correctly exposured shots. Without -1 EV or -1 1/3 EV all shots get overexposured with my SX50 HS in HiSpeed burst mode!
No real idea about this one, maybe the canon firmware still thinks it's using ISO 800?

For both of these issues, it would be helpful if other SX50 owners can check.
« Last Edit: 27 / February / 2014, 17:21:34 by canontestit »


Re: SX50 HS: Where can I report a possible BUG?
« Reply #4 on: 28 / February / 2014, 00:34:51 »
@Waterwingz:

You wrote:
Quote

From what I can tell, there is a little bug in the current AutoISO code. It does not set an Av value (f-stop).   So cameras like the SX50,  which have an adjustable iris, will use whatever value the Canon firmware wants to use. And that setting will be totally unrelated to the exposure settings the AutoISO algorithm calculates for shutter speed and ISO setting.   I can't tell for sure,  but that might be the root of your problem.

What do you mean with "bug in the current AUTO-ISO-Code"?
The official firmware or the CHDK CUSTOM-AUTO-ISO settings/code?


Thanks and best regards
canontestit

« Last Edit: 28 / February / 2014, 01:43:00 by canontestit »

Re: SX50 HS: Where can I report a possible BUG?
« Reply #5 on: 28 / February / 2014, 05:23:03 »
What do you mean with "bug in the current AUTO-ISO-Code"?
The official firmware or the CHDK CUSTOM-AUTO-ISO settings/code?
The bug is in the CHDK CUSTOM-AUTO-ISO code.

Update :  I took a look and I no longer believe there is a bug related to not setting an Av value for cameras with adjustable apertures.   At the point where the autoiso code runs,  the Av value should already be set. The code just adjusts the Tv and Sv values proportionately.
« Last Edit: 07 / March / 2014, 18:54:46 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16

Re: SX50 HS: Where can I report a possible BUG?
« Reply #6 on: 23 / February / 2015, 16:19:53 »
Hi,

are there any news concerning the problem that one has to set
 EV-Correction -1 1/3
when replacing the high ISO values with Auto ISO and using burst mode?

Best regards
canontestit

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Offline srsa_4c

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Re: SX50 HS: Where can I report a possible BUG?
« Reply #7 on: 24 / February / 2015, 19:26:36 »
are there any news concerning the problem that one has to set
 EV-Correction -1 1/3
when replacing the high ISO values with Auto ISO and using burst mode?
I'd suggest you to try regular exposure overrides (Av, Tv, ISO) in hispeed burst mode, and do another test run in single shot mode (P, for example) for comparison. Post the results here.


 

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