GPSeismic FAQs QuikCon

QuikCon FAQs

Placing HIs in the database

Q - I'm not sure if we're doing something wrong but I have found that when I export data from QuikCon into Quikview it takes the height of the instrument station across as the rod height for all the side shots from that station. It looks to to as though it is taking the wrong column across - using the HI column from QuikCon instead of the HR column.

A - QuikView shows the HI's initially in the Antenna Height dialog. You could actually change these which would affect all stations that were shot from a particular setup. After populating the database, the HI's go into the HI field and the HR's go into the 'HR' field if, when you created the database, you chose to use the 'conventional' field structure for the last several fields. If you went with the default field structure, the HI is placed in the 'Unit Variance' field. This might be why you think the HI's didn't make it into the database.

x +
Combining Traverses

Q - How do I combine two traverses that connect but were shot in opposite directions.

A - Reverse the order of one traverse using 'Reverse Observations' in the Edit menu of the DCO editor. This re-orders the DCO observations, switching the 'Pcod's of back sights and foresights and changing the instrument and back sight IDs accordingly. This feature can assist the user in saving one set of observations in which direction is consistent even if the line was shot in several segments in different directions.

This utility requires that observations begin with a back sight and end with a foresight.

x +
Parallax and Refraction

The following may help you decide whether to correct for correct for parallax and refraction if you use the Altitude sunshot method .My knowledge of this comes from two sources... Surveying Theory and Practice Andeson and Mikhali Sokkia Celestial Observation Handbook In both references, it is implied that the corrections should be made for the Altitude Method. Here are the corrections QuikCon makes.

Correction For Parallax = 8.94 * SIN(Zenith Angle)

Note that this correction is in seconds so even if the sun was on the horizon, the adjustment would be 8.94 seconds. It therefore does not account for a lot.

Correction For Refraction = 0.00452 * Pressure * TAN(Zenith Angle) / Temperature

Note that pressure is in millibars and temperature in Kelvin. Note that this correction is in degrees. Since the refraction correction varies as a tangent to the zenith angle, an observation at 45 degrees would generally yield a 50 second correction. An observation at 85 degrees would yield a correction of over 11 minutes. The total correction is applied as follows:

Zenith Angle = Zenith Angle - Correction For Parallax + Correction For Refraction')

x +
File Transfer With TDS Firmware

If you have TDS firmware in an HP48, you can use QuikComm to transfer RW5 files. We have a web page that shows you how:

Using Kermit For File Transfers

x +

QuikCon FAQs

Sunshot Ephemeris

Q - How far back can I go when using the sunshot program in QuikCon? I have some old observations and I'm concerned about using the computed ephemeris values.

A - If you enter high resolution ephemeris from a outside source, it doesn't matter. The following link provides ephemeris backwards through 1995:

Nasa ephemeris

If you go with the computed ephemeris, I feel comfortable with the late 1980's. I say this because I can enter 1994 observations and use the presently computed ephemeris to derive results within 10-13 seconds or so. So I suspect that if it can be trusted to provide that kind of accuracy 7 years in the future, the same should hold true in reverse.

x +
Do you have training videos?

A - We have the following videos.

QuikCon - Part 1 (6MB)
QuikCon - Part 2 (10MB)
QuikCon - Part 3 (8MB)
QuikCon - Part 4 (8MB)
QuikCon - Part 5 (10MB)

x +
Missing HRs

Q - When exporting conventional data using QuikView, after the database is populated, the HI's are there, but not the HR's, Wassamatta?

A - QuikView shows the HI's initially in the Antenna Height dialog. You could actually change these which would affect all stations that were shot from a particular setup. After populating the database, the HI's go into the HI field and the HR's go into the 'HR' field if, when you created the database, you chose to use the 'conventional' field structure for the last several fields. If you went with the default field structure, the HI is placed in the 'Unit Variance' field. This might be why you think the HI's didn't make it into the database.

x +

QuikCon FAQs

Mis-closure Values

Q - How are the various mis-closure values computed?

A - Horizontal Ratio - The reciprocal of the difference between computed and known coordinates divided by the cumulative slope distance at that point.

Vertical Ratio - The reciprocal of the difference between computed and known height divided by the cumulative slope distance at that point.

Vertical QC - Difference between computed and known height divided by square root of cumulative slope distance divided by 1000.

Azimuth Constant - Difference between computed and known azimuths in seconds divided by number of setups at that point.

So if, at some point, we had a mis-tie of 1 meter and the cumulative slope distance of 10,000 meters the Horizontal Ratio would be 1:10,000.

If for some reason at this point, the height mis-tied by 25 meters we would have a Vertical ratio of 1:400 and the Vertical QC would be computed by

25 / SQRT(10000/1000) = 7.9

If at this point, there was a mis-tie of 1 minute between computed and known azimuths, and there were 5 setups prior, then the Azimuth Constant would be 60/5=12.

Nominal Vertical QC - Spreadsheet cells are colored red if values in those cells are greater than the numbered entered by the user.

Nominal Azimuth Closure - Spreadsheet cells are colored red if values in those cells are greater than the numbered entered by the user (DD.MMSSss)

Nominal Azimuth Constant - Spreadsheet cells are colored red if values in those cells are greater than the numbered entered by the user.

x +
Azimuth Mis-closures

Q - Why are the azimuth misclosures different in the classic report and the sreadsheet? Also, what is the azimuth constant?

A - In the classic report, the azimuth closure is in DDD.MMSS format, for example:

000.0237 ( 000 degrees 02 minutes 37 seconds)

In the spreadsheet, it is in DD.ddddd format:

0.0436121666 degrees (which is 000.0237 in DDD.MMSS)

If you check the formatting checkbox in the spreadsheet, the column will be displayed in DDDMMSS format.

The azimuth constant is the azimuth difference in seconds divided by the number of setups at that point:

0.0436121666 * 3600 / 66 = 2.38

x +
Use of TI points

TI points are similar to side shots but have one addiional use, namely, to fix azimuths during processing. If you shoot one or more TI points and you know the foresight azimuths for these shots, it's possible to use this information to fix back sight azimuths during processing. You must place the known azimuth to the TI point in the Comment column of the TI record in the DCO editor (Face 1 if there are 2 faces). The entry must be in the form of 'TI=DDD.MMSS'. For example, if the foresight azimuth to the TI point is 90 degrees 12 minutes, 11 seconds, the entry would be 'TI=090.1211'.

When processing the QCN file, you must elect to fix back sight azimuths and you must have specified a QCC file (even if you are not using any stations in it). The difference between the computed azimuth to the TI and the known azimuth to the TI will be applied to the back sight azimuth of the next setup in the traverse. For all essential purposes, the appearance in the spreadsheet will be exactly like a fixed back sight azimuth and the difference can be prorated if required.

x +