Tim says:

"For info, the strip positions etc. come directly from the shift averages 
(so what is in the measurement list), not from any particular peaks.

One thing to check is whether this is due to multiple shift lists. It is 
possible that one of spectra in the windows used by this popup is using a 
different shift list, and hence values sometimes come from a different 
source (occassionally and randomly given the nature of sets).

I have put in a fix to try to cope better with a mixed shift list 
situation (i.e. for the match & query spectra). However, ideally all 
spectra (via the experiment's link) should be set to use the same shift 
when using this system, otherwise things won't necessarily line up.

If shift lists are not the problem, I guess we'll have to look at the 
project..."

Wayne

On Mon, 20 Apr 2009, Dr. Pryank Patel wrote:

>
> Hi,
> The peaks closer to 118.1 (one hncaco peak is at 117.9, all the others are at 
> 118.1 and 118.2). I may be wrong, but I don't think it's a referencing issue, 
> otherwise would I not see this feature with every spin system? If I look in 
> Data Analysis:Measurement Lists, the HN chemical shift for that spin system 
> is 118.1, which is what I expect. Therefore, this is shift averaging?
>
> The (i+1) residue has a HN chemical shift of 117.2, perhaps it is taking some 
> of these peaks as well?
>
> Pryank
>
>
> Wayne Boucher wrote:
>> Hello,
>> 
>> If you look at the peaks in the spin system are they at (well, near) 118.1 
>> or instead 117.4?  So is the shift averaging screwing up or is the 
>> referencing of one or more of the spectra out?
>> 
>> Wayne
>> 
>> On Fri, 17 Apr 2009, Dr. Pryank Patel wrote:
>>
>> 
>>> Hi All,
>>> Apologies if this relatively minor issue has come up in the past, but I 
>>> have not been able to find anything relevant in the archives so far.
>>> 
>>> While conducting a backbone assignment, I have noticed an inconsistency in 
>>> the "Link Sequential Spin Systems" popup, in the spin systems table, in 
>>> terms of the position of one of my spin systems compared with the position 
>>> of that spin system in the hsqc. It seems to be off by 0.7ppm in the 15N 
>>> dimension (117.4ppm instead of 118.1ppm). The result is that when I click 
>>> on this spin system, with a hncocacb spectra as the query spectra, the 
>>> query window goes to 117.4ppm, for which there are no peaks for that spin 
>>> system.
>>> 
>>> Should I be concerned? Is there any way to trace where it seems to be 
>>> getting this information from? Should I be checking all of the spin 
>>> systems for inconsistencies?
>>> 
>>> Best wishes,
>>> Pryank
>>>
>>>