Sony A7rIII (ILCE-7RM3A) ptp --trigger-capture leaves camera writing to memory card forever

[thcipriani]

The sony a7riii in PC Control Mode can only take one image every two seconds. This is because writing to the memory card seems to requires the ptp_getobject function called from camera_wait_for_event inside camlibs/ptp2/library.c.

This means gphoto2 --trigger-capture triggers shutter release, but leaves the camera unable to perform any other commands until gphoto2 --capture-image is called (as it subsequently calls ptp_getobject). Capture image seems to be downloading all the images from the cameras sdram into my computer's memory (is that right?), so this limits how fast I can trigger photos.

gphoto2 --trigger-capture --wait-event=FILEADDED also works, but is just as slow.

time gphoto2 --set-config shutterspeed=1/1000 --trigger-capture --wait-event=FILEADDED
Waiting for 'FILEADDED' event from camera. Press Ctrl-C to abort.              
UNKNOWN PTP Event c202, Param1 ffffc001
UNKNOWN PTP Property 5004 changed, "imagequality" to "RAW"
UNKNOWN PTP Property d21d changed, "PTP Property 0xd21d" to "0"
UNKNOWN PTP Event c201, Param1 ffffc001
FILEADDED capt0000.arw /                                                       
event found, stopping wait!

real    0m2.277s
user    0m0.059s
sys     0m0.085s

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Details

Calling gphoto2 --trigger-capture triggers a shutter release, but then there's a memory card status indicator that shows 1 image writing to the memory card. Subsequent calls to gphoto2 --trigger-capture do nothing—they exit successfully without error, but no image capture is triggered, debug output for those calls looks fine—it's sending ptp commands to the camera successfully and thinks it's clicking the shutter.

The only way I've found to flush the image from the buffer to the memory card is by calling: gphoto2 --capture-image (or gphoto2 --wait-event=FILEADDED)—this downloads the image to the card without taking a new image (debug indicates it's clicking the shutter—but the camera isn't doing anything).

The crux of this seems to be ptp_getobject function called from camera_wait_for_event inside camlibs/ptp2/library.c—if I return from camera_wait_for_event before ptp_getobject, the image is never flushed. If I return right after calling ptp_getobject: capture is written to the sdcard.

I worked around this (a bit) by setting continuous release capture mode:

gphoto2 --set-config /main/capturesettings/capturemode=29 # Choice: 29 Bracketing C 3.0 Steps 5 Pictures
gphoto2 --bulb 5 --capture-image

The camera lets you take a bunch of pictures, but then won't let you change camera settings or trigger another shutter release until it's done the camera→computer→camera dance.

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Name the camera

Model                          Port
----------------------------------------------------------
Sony ILCE-7RM3A (PC Control)   usb:001,100

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libgphoto2 and gphoto2 version

gphoto2 2.5.28

Copyright (c) 2000-2021 Marcus Meissner and others

gphoto2 comes with NO WARRANTY, to the extent permitted by law. You may
redistribute copies of gphoto2 under the terms of the GNU General Public
License. For more information about these matters, see the files named COPYING.

This version of gphoto2 is using the following software versions and options:
gphoto2         2.5.28         gcc, popt(m), exif, no cdk, no aa, jpeg, no readline
libgphoto2      2.5.31.1       standard camlibs (SKIPPING docupen lumix), gcc, no ltdl, EXIF
libgphoto2_port 0.12.2         iolibs: disk ptpip serial usb1 usbdiskdirect usbscsi, gcc, no ltdl, EXIF, USB, serial without locking

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I haven't been able to find any other reports of this issue, so I thought I'd at least document it. Or perhaps there's some setting somewhere I missed. Please let me know if more details are helpful.

[knro]

Not sure if it is a similar issue, but a user reported failure with Sony DSC-A7r IV (Control) using:

gphoto2 --debug --debug-logfile=gphoto.txt --capture-image-and-download

With this relevant failure:

3.310606 camera_sony_capture [library.c:4936](0): 'ptp_generic_getdevicepropdesc (params, PTP_DPC_CompressionSetting, &dpd)' failed: PTP General Error (0x2002)
3.310620 gp_camera_capture [gphoto2-camera.c:1339](0): 'camera->functions->capture (camera, type, path, context)' failed: -1
ERROR: Could not capture image.

ERROR: Could not capture.

This is using latest libgphoto2 just compiled from master a couple of weeks ago. Full debug output attached.

gphoto.txt

[thcipriani]

@knro your problem looks slightly different. The line right before the debug lines you quoted seem to indicate that libgphoto2 can't find property 0x5004 which is most sony alpha cameras' CompressionSetting. So when the camera_sony_capture function tries to grab the compression setting you get that.

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My problem turns out to be not a bug, the A7riii just doesn't allow you to save an image to the camera only. It's described in the AlphaFairy docs:

The solution was to simply read out the buffer into nothingness.

Which is exactly what libgphoto2 does, so success(?)

I wish sony would let me save to the camera only in ptp mode :(

[knro]

Thank you @thcipriani for the insight. So is the lack of CompressionSetting a fatal failure then? would it be possible to capture without relying on this setting somehow?

[msmeissn]

You can check out if there is a "capturetarget" setting. this would allow changing the capturetarget to the card on newer Sonys.

I think the A7C and AZR3a have it.

[msmeissn]

For the compression setting perhaps open a new issue.

[thcipriani]

You can check out if there is a "capturetarget" setting. this would allow changing the capturetarget to the card on newer Sonys.

I think the A7C and AZR3a have it.

There is a capturetarget in the gphoto2 config for the a7riii and I have it set to the camera's card via gphoto2 --set-config capturetarget=1 and it persists when I do gphoto2 --get-config

BUT, on the camera itself, under "menu" → "setup4" → "PC Remote Settings" → "Still Image Save Destination" there are only two options "PC Only" and "PC+Camera"

Some models appear to have "Camera Only"; however, in my case (where that option does not appear) it seems I have to read out the camera buffer BEFORE the camera will write to the card :(