Image display delay

[ben robinson]

very interesting feedback.  thank you, peter.

On Tue, Apr 14, 2009 at 10:37 PM, Peter Quain <pquain at une.edu.au> wrote:

>
> BTW, variability of 8 to 14 ms could reflect differing time to process
> image (write to video memory). If images are same size (kb) this could mean
> that your machine's video drivers and e-prime don't talk well. If they are
> different sizes and driver communication IS ok, the larger images should be
> those where delay is longest. You might need to check your machine's
> suitability for visual stimulus presentation (nVidia drivers sometimes show
> large slop .. if you have nVidia chip, try ATI radeon card maybe, if this is
> the case).
>
> At 12:22 PM 15/04/2009, you wrote:
>
> Dear David
>         I have read Chapter 3 of Userguide thoroughly, but still feel a
> little confusion. In each block of my programme, there was a TextDisplay, a
> Inline Scripe and a ImageDisplay(stimulous).To synchronize the signal of
> NeroScan and the stimuli of e-Prime, I have inverted a in-line WritePort
> command before "ImageDisplay" and set the PreRelease time (100ms) in the
> TextDisplay. However, the unwanted delay or unsynchronization still existed
> between the e-Prime and EEG recording system result in anormal delay of N170
> component. Thus, I want to ask whether the WritePort command was sent to the
> recording system at the beginning of Prelease time or at the point when
> stimulous presents on the screen. In other word, I want to know whether the
> WritePort command and image were sent at the same time from E-Prime.
>       Thank you for your concerning.
>
>
> > Date: Wed, 8 Apr 2009 11:26:12 -0400
> > To: e-prime at googlegroups.com
> > From: mcfarla9 at msu.edu
> > Subject: Re: Image display delay
> >
> >
> > At 4/5/2009 09:35 PM Sunday, maocong wrote:
> > >I am a greenhand in programming on e-prime, and I need some help on
> > >the fellowing issue:
> > >
> > >I designed an ERP visual stimulous experiment by using the control of
> > >ImageDisplay on e-Prime 2.0v and the EEG recording system is NeroScan
> > >4.3v. And I found a 8~14ms delay on image display(shown by the
> > >programme running result file), and the help file showed this delay is
> > >the difference between orignial onset time and actual display time.
> > >This random image display delay greatly effect the accuracy of N170
> > >latency recorded, which lead to the unreliablity of the experiment
> > >result. Therefore I hope you can give me some advices about how to
> > >eliminate/compensate this display delay or how to uniform this display
> > >delay
> >
> > Please read thoroughly chapter 3 ("Critical timing...") of the User's
> > Guide that came with E-Prime.
> >
> > -- David McFarlane, Professional Faultfinder
> >
> >
> > More than mail–Windows Live™ goes way beyond your inbox.ox. More than
> messages <http://www.microsoft.com/windows/windowslive/>
>
>
> >
>

--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "E-Prime" group.
To post to this group, send email to e-prime at googlegroups.com
To unsubscribe from this group, send email to e-prime+unsubscribe at googlegroups.com
For more options, visit this group at http://groups.google.com/group/e-prime?hl=en
-~----------~----~----~----~------~----~------~--~---

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listserv.linguistlist.org/pipermail/eprime/attachments/20090414/363776d7/attachment.htm>