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Solution for empty (0 byte) CRW raw files

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Solution for empty (0 byte) CRW raw files
« on: 28 / August / 2010, 19:05:09 »
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I couldn't figure out why I was getting raw files but they were blank, empty files.

I discovered that my card was too small... put in a higher capacity card and everything was better.  Duh!  :P

Hope this helps someone else.

Re: Solution for empty (0 byte) CRW raw files
« Reply #1 on: 29 / January / 2011, 05:57:47 »
I get 0 byte crw files on my canon 110IS but have an 8 gig card! any ideas why?

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Offline vit40

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Re: Solution for empty (0 byte) CRW raw files
« Reply #2 on: 29 / January / 2011, 07:00:51 »
From my remembering, on some cameras there was an issue about empty raws, that occured if you press the shutter too fast. If you half press the shutter, wait the camera to focus and then fully press the shutter, raws were ok. On some cameras, it was corrected (like my A650), but it is possible that fix doesnt work (or wasn't made) for all cameras

Re: Solution for empty (0 byte) CRW raw files
« Reply #3 on: 29 / January / 2011, 07:39:07 »
I have also an SX110 IS with 8GB SD card. I get also 0 bytes CRW files with the latest 0.9.9-1053 build. I have also tried with a small 32 MB card and the result is the same. What I noticed that the available space is decreased by 15 MB but the .CRW file is still 0. Taking picture also takes more time with raw saving enabled as it should but still resulting empty file. Maybe there is some problem with disk access.
Does anyone know what could be the problem?


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Offline reyalp

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Re: Solution for empty (0 byte) CRW raw files
« Reply #4 on: 29 / January / 2011, 17:26:27 »
Are you retrieving the raw files with USB camera connection, or a card reader ? If you aren't using a card reader, try that.
Don't forget what the H stands for.

Re: Solution for empty (0 byte) CRW raw files
« Reply #5 on: 30 / January / 2011, 01:45:24 »
I have used card reader. As I wrote earlier the space is decreased by ~15MB but the file itself is only 0. I have fixed the card with "chkdsk e: /F". It restores the file which is 15 MB but it is full with 0x00 in hexadecimal view.
I have tried to save in .DNG. In this case files with 38400 bytes are created. Again chkdsk helps, it restore the file to 15507456 bytes but data from 38400 offset is only 0x00.
Is these related maybe to timeout problem?

Re: Solution for empty (0 byte) CRW raw files
« Reply #6 on: 31 / January / 2011, 19:55:43 »
I get exactly the same sized DNG as you. Maybe there is an error in the build? Any further ideas anyone as It would be great to actually shoot raw with my 110IS


Dan

Re: Solution for empty (0 byte) CRW raw files
« Reply #7 on: 02 / February / 2011, 04:31:30 »
Finally I have solved the problem with a small correction in the code in raw.c in function raw_savefile:

            if (conf.dng_raw) {
                // Write alternate (inactive) buffer that we reversed the bytes into above (if only one buffer then it will be the active buffer instead)
//                write(fd, (char*)(((unsigned long)altrawadr)|CAM_UNCACHED_BIT), hook_raw_size());
                write(fd, (char*)(((unsigned long)altrawadr)), hook_raw_size());

            } else {
                // Write active RAW buffer
                   
    //                write(fd, (char*)(((unsigned long)rawadr)|CAM_UNCACHED_BIT), hook_raw_size());
                write(fd, (char*)(((unsigned long)rawadr)), hook_raw_size());


            }
            close(fd);
            utime(fn, &t);


So basically the address is not changed by bitwise OR (CAM_UNCACHED_BIT) when calling "write()" from now. With this sollution it works with canon SX110is with RAW and with DNG files.


Could some developer put it in the source behind a conditional switch or whatever so later releases will also work with SX110is?
Anyway is this the right place to suggest correction?


Re: Solution for empty (0 byte) CRW raw files
« Reply #8 on: 03 / February / 2011, 22:11:17 »
Hi Richlock

Wow great we have an answer, awesome!

How can I  make this change and get it to work for me?

thanks

Dan Raymond

Re: Solution for empty (0 byte) CRW raw files
« Reply #9 on: 04 / February / 2011, 04:38:56 »
Where can I get the source code and recompile with the appropriate changes?

Thanks for help

Dan Raymond

 

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