PowerShot SX220 HS - Porting Thread - page 20 - General Discussion and Assistance

philmoz

3445

Re: PowerShot SX220 HS - Porting Thread

« Reply #190 on: 22 / June / 2011, 18:40:21 »

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Quote from: Blablaat on 22 / June / 2011, 18:26:41

But older camera's do produce DNGs that are corrected and "the same" as the JPEGs right? Is this because of the fact that the SX220 uses a newer digic processor?

Older cameras had less lens distortion. With the additional processing power now available in the cameras they can use cheaper lens designs with more distortion and correct it in the camera software. The average user can't tell the difference since they never see the 'RAW' image.

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CHDK ports:
sx30is (1.00c, 1.00h, 1.00l, 1.00n & 1.00p)
g12 (1.00c, 1.00e, 1.00f & 1.00g)
sx130is (1.01d & 1.01f)
ixus310hs (1.00a & 1.01a)
sx40hs (1.00d, 1.00g & 1.00i)
g1x (1.00e, 1.00f & 1.00g)
g5x (1.00c, 1.01a, 1.01b)
g7x2 (1.01a, 1.01b, 1.10b)

Blablaat

53

Re: PowerShot SX220 HS - Porting Thread

« Reply #191 on: 22 / June / 2011, 18:59:36 »

I think I get it. So my old Ixus 80 apparently produces a DNG that is practically is the same (it's hard to see the difference) as the JPEG because the distortion is close to zero.

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reyalp

13940

Re: PowerShot SX220 HS - Porting Thread

« Reply #192 on: 22 / June / 2011, 23:09:54 »

Quote from: Blablaat on 22 / June / 2011, 18:59:36

I think I get it. So my old Ixus 80 apparently produces a DNG that is practically is the same (it's hard to see the difference) as the JPEG because the distortion is close to zero.

Exactly. The faster DSP gets, the less "raw" looks like a usable image. The raw (including the image data portion of the DNG) is always whatever the sensor spat out, that part doesn't change. Because it's the same data that canon used to generate the jpeg, you can always do the same thing on the PC in theory.

DNG 1.3 does have some opcodes for geometric corrections, it's possible that these could be used to inform image processing programs what needs to be done. I don't know how widely support these are, or whether they are sufficient to correct the distortion in these cameras. Might be worth investigation.

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Don't forget what the H stands for.

Bonanza

1

Re: PowerShot SX220 HS - Porting Thread

« Reply #193 on: 23 / June / 2011, 08:09:49 »

Funnel:
Just want to thank you for your work on this port.
I am really thankful.
Have just tested Ultra Intervalometer and it works good.

/Micke in Sweden

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ratz1967

10

Re: PowerShot SX220 HS - Porting Thread

« Reply #194 on: 23 / June / 2011, 22:59:39 »

If it goes to intervalometer scripts for timelapse video purposes:
In scenery mode ("miniature mode" selected) there i the possibility to change the fps to 4,8fps (5x) 2,4fps (10x) and 1,2fps (20x). The problem is: These timelapse videos have the typical miniature mode touch(overcontrasted and blurred on the top and bottom). Is there the slight possibility that this function can be used in normal video mode?
Would be great and makes the intervalometer obsolete for the most users. Its a nice to have, wich can be tended to when CHDK is nearly finished for this cam.

In an earlier post someone has asked for superfine mode because of the noise in the pictures:
Try some trick from ancient times of Powershot 600 (640x480pixel with a camera in the format of a lunchbox):

The noise is nearly all in the blue part of the picture.
divide the picture in your graphic program in RGB(K) (4 pictures) and give oooonly the blue channel-picture the slightest touch of gaussian unsharpness and pack them back together.
Most, if not all of the noise will vanish with no visible unsharpness in the whole picture...

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SX220HS + SX200is + S30 + Powershot 600

mark0326

1

Re: PowerShot SX220 HS - Porting Thread

« Reply #195 on: 24 / June / 2011, 06:02:45 »

Great work being done here, many thanks.
Had this camera a week & still getting to grips with CHDK, mainly want it for time-lapse suspended from a kite... is it possible to have the LCD go blank after script starts working to save precious power?
Cheers.

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funnel

349

Re: PowerShot SX220 HS - Porting Thread

« Reply #196 on: 24 / June / 2011, 08:57:32 »

I tried some scripts that turn the lcd off without success. Some cameras use the DISP button to turn the screen off and the scripts just emulate the press disp button. You can also turn the backlight off in ubasic by using the "set_backlight 0" but as soon as the shoot is taken it turns the backlight back on. You can check the scripts section maybe you find something I missed.

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marcobolten

8

Re: PowerShot SX220 HS - Porting Thread

« Reply #197 on: 24 / June / 2011, 18:24:53 »

Hi, I am really happy with the beta5! There's one little thing I noticed, though: I sometimes like to play around in the games section - and the color tables of the games would need some correction to make them playable. It's no "must have", of course :-)

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funnel

349

Re: PowerShot SX220 HS - Porting Thread

« Reply #198 on: 25 / June / 2011, 04:48:19 »

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funnel

349

Re: PowerShot SX220 HS - Porting Thread

« Reply #199 on: 25 / June / 2011, 08:52:11 »

I uploaded a new version.

Fixed:
-raw files saving in folder with jpgs now is working for both mothly and daily folder naming
-a workaround for grids. They're centered now and only 4:3 and stay the same in all modes. I solved it by shifting every x1 and x2 60 pixels to the right.

Code: [Select]

#define ASPECT_GRID_XCORRECTION(x) ( (((x)<<3)/8)+60 )-made a new CAM_BITMAP_PALETTE 9 that corrects some color defines.
-corrected the games colors.

Binary beta7 http://www.zshare.net/download/91870000e59934f3/

Source beta7 http://www.zshare.net/download/91913003c7fea79c/

« Last Edit: 26 / June / 2011, 11:28:48 by funnel »

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