On 13/09/2021 16:40, Mike Scott wrote:
I hope this isn't an inappropriate forum for this topic.
Our church has a newish optoma projector, and I've been trying to use
this with a recent dell laptop (hdmi output).
The problem is that whenever I've connected them up at the church, the
projector declares there's nothing connected, while the laptop can
'see' the projector but won't allow its use. This state persists
across all reboots and cable changes -- but will suddenly after
minutes (a good 3/4 hour yesterday) suddenly burst into life and work
perfectly, all of its own accord.
Yesterday, apart from reseating the connectors, we tried 3 cables of
varying length (all failed). The laptop was fine running into a TV
display, and the projector worked happily connected to a someone's
tablet's hdmi output. Yet lappy plus projector failed for the extended
period before bursting spontaneously into operation.
The laptop is running a recent Mint - the monitor preferences box
detects and shows the projector and allows the usual operations, which
apparently succeed. Applications like Libreoffice and OBS which could
use the second screen do not however (in the 'fault' state) offer that
option at all.
OTOH, I've tried the exact same combo at home today, and it works 100%
perfectly, and I cannot make it fail.
I'm wondering about hdmi tolerances - might the lappy be on an edge in
one direction, the projector in the other? Otherwise it can only,
surely, be gremlins :-|
Any help would be appreciated - thanks.
Might be worth looking into HDCP..... This is a content protection
system so maybe the two are not agreeing on HDCP and hence the
connection fails.
I hope this isn't an inappropriate forum for this topic.
Our church has a newish optoma projector, and I've been trying to use
this with a recent dell laptop (hdmi output).
The problem is that whenever I've connected them up at the church, the projector declares there's nothing connected, while the laptop can 'see'
the projector but won't allow its use. This state persists across all
reboots and cable changes -- but will suddenly after minutes (a good 3/4
hour yesterday) suddenly burst into life and work perfectly, all of its
own accord.
Yesterday, apart from reseating the connectors, we tried 3 cables of
varying length (all failed). The laptop was fine running into a TV
display, and the projector worked happily connected to a someone's
tablet's hdmi output. Yet lappy plus projector failed for the extended
period before bursting spontaneously into operation.
The laptop is running a recent Mint - the monitor preferences box
detects and shows the projector and allows the usual operations, which apparently succeed. Applications like Libreoffice and OBS which could
use the second screen do not however (in the 'fault' state) offer that
option at all.
OTOH, I've tried the exact same combo at home today, and it works 100% perfectly, and I cannot make it fail.
I'm wondering about hdmi tolerances - might the lappy be on an edge in
one direction, the projector in the other? Otherwise it can only,
surely, be gremlins :-|
Any help would be appreciated - thanks.
On 13/09/2021 16:40, Mike Scott wrote:
I hope this isn't an inappropriate forum for this topic.
Our church has a newish optoma projector, and I've been trying to use
this with a recent dell laptop (hdmi output).
The problem is that whenever I've connected them up at the church, the
projector declares there's nothing connected, while the laptop can
'see' the projector but won't allow its use. This state persists
across all reboots and cable changes -- but will suddenly after
minutes (a good 3/4 hour yesterday) suddenly burst into life and work
perfectly, all of its own accord.
Yesterday, apart from reseating the connectors, we tried 3 cables of
varying length (all failed). The laptop was fine running into a TV
display, and the projector worked happily connected to a someone's
tablet's hdmi output. Yet lappy plus projector failed for the extended
period before bursting spontaneously into operation.
The laptop is running a recent Mint - the monitor preferences box
detects and shows the projector and allows the usual operations, which
apparently succeed. Applications like Libreoffice and OBS which could
use the second screen do not however (in the 'fault' state) offer that
option at all.
OTOH, I've tried the exact same combo at home today, and it works 100%
perfectly, and I cannot make it fail.
I'm wondering about hdmi tolerances - might the lappy be on an edge in
one direction, the projector in the other? Otherwise it can only,
surely, be gremlins :-|
Any help would be appreciated - thanks.
Might be worth looking into HDCP..... This is a content protection
system so maybe the two are not agreeing on HDCP and hence the
connection fails.
On 13/09/2021 16:49, SH wrote:
On 13/09/2021 16:40, Mike Scott wrote:
I hope this isn't an inappropriate forum for this topic.
Our church has a newish optoma projector, and I've been trying to use
this with a recent dell laptop (hdmi output).
The problem is that whenever I've connected them up at the church,
the projector declares there's nothing connected, while the laptop
can 'see' the projector but won't allow its use. This state persists
across all reboots and cable changes -- but will suddenly after
minutes (a good 3/4 hour yesterday) suddenly burst into life and work
perfectly, all of its own accord.
Yesterday, apart from reseating the connectors, we tried 3 cables of
varying length (all failed). The laptop was fine running into a TV
display, and the projector worked happily connected to a someone's
tablet's hdmi output. Yet lappy plus projector failed for the
extended period before bursting spontaneously into operation.
The laptop is running a recent Mint - the monitor preferences box
detects and shows the projector and allows the usual operations,
which apparently succeed. Applications like Libreoffice and OBS which
could use the second screen do not however (in the 'fault' state)
offer that option at all.
OTOH, I've tried the exact same combo at home today, and it works
100% perfectly, and I cannot make it fail.
I'm wondering about hdmi tolerances - might the lappy be on an edge
in one direction, the projector in the other? Otherwise it can only,
surely, be gremlins :-|
Any help would be appreciated - thanks.
Might be worth looking into HDCP..... This is a content protection
system so maybe the two are not agreeing on HDCP and hence the
connection fails.
Thanks for the thought, but hdcp issues would presumably cause a hard failure. I can't see it failing for a while, then suddenly working. And
it works today just as we'd want.
BTW the content isn't - or rather, I can't see why it would be -
protected. All home-brew presentation stuff. Works fine with lappy plus
home TV, which is probably going to be more picky than a projector.
The problem is that whenever I've connected them up at the church, the projector declares there's nothing connected, while the laptop can 'see'
the projector but won't allow its use. This state persists across all
reboots and cable changes -- but will suddenly after minutes (a good 3/4
hour yesterday) suddenly burst into life and work perfectly, all of its
own accord.
Mike Scott <usenet.16@scottsonline.org.uk.invalid> wrote:
The problem is that whenever I've connected them up at the church, the
projector declares there's nothing connected, while the laptop can 'see'
the projector but won't allow its use. This state persists across all
reboots and cable changes -- but will suddenly after minutes (a good 3/4
hour yesterday) suddenly burst into life and work perfectly, all of its
own accord.
Is this an on-the-ceiling projector or a table one? Is there anything
between the laptop and the protector (video switch, booster, etc)? Can you try a 1m cable direct into the projector, skipping anything else that might be installed?
Mike Scott <usenet.16@scottsonline.org.uk.invalid> wrote:
The problem is that whenever I've connected them up at the church, the
projector declares there's nothing connected, while the laptop can 'see'
the projector but won't allow its use. This state persists across all
reboots and cable changes -- but will suddenly after minutes (a good 3/4
hour yesterday) suddenly burst into life and work perfectly, all of its
own accord.
Is this an on-the-ceiling projector or a table one? Is there anything
between the laptop and the protector (video switch, booster, etc)? Can you try a 1m cable direct into the projector, skipping anything else that might be installed?
Theo
On 13/09/2021 17:07, Mike Scott wrote:...........
On 13/09/2021 16:49, SH wrote:
On 13/09/2021 16:40, Mike Scott wrote:
I hope this isn't an inappropriate forum for this topic.
Our church has a newish optoma projector, and I've been trying to
use this with a recent dell laptop (hdmi output).
The problem is that whenever I've connected them up at the church,
the projector declares there's nothing connected, while the laptop
can 'see' the projector but won't allow its use. This state persists
across all reboots and cable changes -- but will suddenly after
minutes (a good 3/4 hour yesterday) suddenly burst into life and
work perfectly, all of its own accord.
Any help would be appreciated - thanks.
Might be worth looking into HDCP..... This is a content protection
system so maybe the two are not agreeing on HDCP and hence the
connection fails.
Thanks for the thought, but hdcp issues would presumably cause a hard
failure. I can't see it failing for a while, then suddenly working.
And it works today just as we'd want.
BTW the content isn't - or rather, I can't see why it would be -
protected. All home-brew presentation stuff. Works fine with lappy
plus home TV, which is probably going to be more picky than a projector.
There are also several versions of HDMI, along with different HDMI cable versions:
https://en.wikipedia.org/wiki/HDMI
https://www.electronics-notes.com/articles/audio-video/hdmi/hdmi-versions.php
https://www.cablestogo.com/learning/library/desktop-connectivity/hdmi-comparison-chart
So might be worth at least checking the HDMI version supported by the
cable exceeds the versions used on the laptop and on the projector.
Also Cable length can be an issue.
Also someone in the newsgroups highlighted an interference issue as HDMI operates at up to 680 MHz.
Theo <theom+news@chiark.greenend.org.uk> wrote:
Mike Scott <usenet.16@scottsonline.org.uk.invalid> wrote:
The problem is that whenever I've connected them up at the church, the
projector declares there's nothing connected, while the laptop can 'see' >>> the projector but won't allow its use. This state persists across all
reboots and cable changes -- but will suddenly after minutes (a good 3/4 >>> hour yesterday) suddenly burst into life and work perfectly, all of its
own accord.
Is this an on-the-ceiling projector or a table one? Is there anything
between the laptop and the protector (video switch, booster, etc)? Can you >> try a 1m cable direct into the projector, skipping anything else that might >> be installed?
Yep. I had issues with my mac when it connected to a 4k TV via an "A/V" breakout box. It was intermittent too. We shortened the cable and it work more reliably.
To the OP do lower resolutions work better?
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