I’d try setting those caps in reverse order, mostly because https://www.twain.org/docs/CapOrderForWeb.PDF says that ICAP_BITDEPTH comes before ICAP_XRESOLUTION & ICAP_YRESOLUTION
Then I’d run the Get triplet after all of my Set triplets to check that the device accepted my Sets (it’s odd but it’s twain)
Then I’d check the twImageInfo while the image was coming down.
If none of that worked I’d test my code against a known device – like a Kodak i30 in simulation mode.
Failing that… yeah I dunno, if none of that works post back.
EDITED: and i’d test this in the twain toolkit to see if the toolkit reproduced my problem, because if the toolkit reproduces your problem it’s more likely a problem with the driver. And with HP devices I would look for the ‘commercial’ or ‘minimal’ driver on the Cd – it isn’t the default and it works better.
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