| Author | Message | |||
     Nick Glover (milkyone) New member Username: milkyone Post Number: 3 Registered: 5-2007 |
Thanks for getting back. I should have updated earlier myself. It took a while to find out that there was a software problem which has been fixed in later versions of Vision. The major problem (found by accident only recently) was a loose external reference tile.Also were having other mechanical problems as well. So it was a reminder to review "photometric stability" as well as other instrument performance monitors. Nick Glover | |||
| Tony Davies (td) Moderator Username: td Post Number: 175 Registered: 1-2001 |
Hello Nick, Sorry, I forgot to look when you first posted your problem. Did you ask Foss? I would think they would know the problem and solution. Your .DOC file does not appear to have registered properly; it is reported as "Not Found". Best wishes, Tony | |||
| Nick Glover (milkyone) New member Username: milkyone Post Number: 2 Registered: 5-2007 |
Hello David and David Thanks, the main problem is not that the reference changes with time. It's that for random periods it does NOT change. The software is telling me that it uses exactly the same reference scan for sequential samples even though reference is scanned each time. This example shows reference taken about nine hours before sample.
This can last for weeks then it Randomly reverts to normal.Doesn't seem any pattern in User or Login etc. Regards Nick Glover | |||
| David Russell (russell) Senior Member Username: russell Post Number: 33 Registered: 2-2001 |
Regarding David Donald's post on ref scan variation. I'm a bit surprised by this comment. I would expect lamp aging to be more of a factor than detector aging. | |||
| David Donald (ddonald) New member Username: ddonald Post Number: 3 Registered: 11-2006 |
Hi Nick, I regularly use FOSS 6500/5000 instruments for which the variation in the reference scans (both the ceramic and polsteryne tiles) is most apparent in ageing detectors. It would be interesting to see what the changes in the reference specta you are reporting so if you are able to post a picture, that would be much appericated. Regards, David Donald. | |||
| Nick Glover (milkyone) New member Username: milkyone Post Number: 1 Registered: 5-2007 |
Hello everyone. I am first time Forum user. I am using several Foss NIRS 6500 Mk 2 sytems running Vision 2.51 Software and set to scan reference for each sample. looking at reference part of spectra, I've seen that consecutive spectra seem to have the same reference for anywhere up to weeks at a time before randomly reverting to change with each scan. Has anyone else seen this and if so what did you do to fix it? We use the reference to account for varying environment. |
Time example