<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
<p>Ralph,</p>
<p>Thanks for the reply.<br>
<br>
I looked at the Genesys Datasheet for the chip (GL646USB) that is
used in the HP4850. I see the register that appears to control
the slide scanning lamp.</p>
<p>Is there another backend that has support for a similar feature?
Possibly I could use that as a template to better understand how
support for this feature might be implemented in the genesys
backend.</p>
<p>Thanks again,</p>
<p>Jon</p>
<p><br>
</p>
<div class="moz-cite-prefix">On 7/31/26 11:21 AM, Ralph Little
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:7c8c105f-1b7d-4461-8a20-e6cb83788192@gmail.com">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
Hi,<br>
According to our Supported Scanners list (<a
class="moz-txt-link-freetext"
href="http://www.sane-project.org/sane-supported-devices.html"
moz-do-not-send="true">http://www.sane-project.org/sane-supported-devices.html</a>)
the genesys backend doesn't yet support the slide scanning feature
of this device. It requires additional code to drive the extra
hardware involved.<br>
We don't have an active maintainer for the genesys backend at the
moment unfortunately, so I don't know when someone would be able
to get to this task in the future. :(<br>
<br>
Regards,<br>
Ralph<br>
<br>
<div class="moz-cite-prefix">On 2026-07-30 20:58, <a
class="moz-txt-link-abbreviated moz-txt-link-freetext"
href="mailto:7xsuazlhhtls@gmail.com" moz-do-not-send="true">7xsuazlhhtls@gmail.com</a>
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:d0f9e851-d9f4-44fd-b3c2-eb6699345df3@gmail.com">
<meta http-equiv="content-type"
content="text/html; charset=UTF-8">
<p><code>I recently acquired an HP Scanjet 4850 scanner. The
document scanning works with no problems. This particular
scanner has a negative/slide scanning component built in to
the lid of the device. This includes a separate lamp to
illuminate the film for scanning. The lamp in the lid comes
when I run a hardware self test procedure but I have not
discovered any way to have the lamp come on when scanning
using sane.<br>
<br>
Is this capability supported?<br>
<br>
info about my setup ---<br>
<br>
HP Scanjet 4850<br>
<br>
$ scanimage -V<br>
scanimage (sane-backends) 1.4.0; backend version 1.4.0<br>
<br>
genesys backend<br>
<br>
Fedora Linux 44 (Workstation Edition)<br>
Linux 7.1.5-200.fc44.x86_64</code></p>
</blockquote>
<br>
</blockquote>
</body>
</html>