wrong Latitude when exporting WP's from TTQV 2.5 in PCX5 for

Hi, I have an old version TTQV 2.5 running on Windows XP that I did not used since several years.
I'm curently preparing with TTQV 2.5 an off-road trip to south-Morocco with Maps en PNG format 1/250'000 provided with corresponding CAL files.

The PCX5 file produced by TTQV 2.5 have slight differences (0.01%) for the Latitude (Longitude is 100% OK). Example in format DD.DDDDD)
Latitude of WP displayed in TTQV 2.5: 30.23212
Latitude of WP produced in PCX5 file: 30.2438545 (Diff. = +0.01%)

Thanks for your assistance to provide explanation and how to fix this mistake. Did I miss some settings or used wrong parameters ?
with kind regards, Tatchin from Switzerland

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Thanks jockel for your quick reply. The PCX5 file exported from TTQV 2.5 has Datum = WGS84 (for GPS device).

The 1/250'000 Mapf of Morocco is a QV Map with Calibration Parameters:
datum1 = 10 = Clarke 1880# 6378249.145# 293.465# 0# 0# 0#
datum2 = 10 =
(remaining parameters are listed at the end of this message)
Questions: 1) does this mean that the CAL file provided for thi QV Map is not 100% accurate and that I have to re-Calibrate the Map in TTQV as explained in TTQV User Manual ?
2) or do you have a quick way / walkaround to adjust the Map Calibration data in order to have those compatible with WGS84 ?
2) could you indicate a document / tutorial explaining the bas + principles of Map Calibration ?
Thanks again for your support and quick replies. Kind rgds, Tatchin

Below the emaining parameters of the QV Map: Morocco / Ouarzazate:
map_idx = 4 = 41
name = 10 = Ouarzazat
mapno = 10 = NH-29-6
fname = 10 = Ouarzazat.PNG
fpath = 10 = C:\WINDOWS\Bureau\maroc\Cartes\
cdlabel = 10 = Marokko_250
del = 1 = 0
nord = 6 = 31.04712
sued = 6 = 29.95329
ost = 6 = -5.955191
west = 6 = -7.557482
scale_map = 6 = 250000
scale_area = 6 = 9.595773E-08
info = 12 =
map_w = 4 = 0
map_h = 4 = 0
proj_mode = 10 = proj
projparams = 10 = proj=utm lon_0=-9 lat_1=28 lat_2=27
map_datum = 3 = 0
deltax = 6 = 0
deltay = 6 = 0
utm_zone = 2 = 0
utm_letter = 10 =
res1 = 10 =
res2 = 10 =
res3 = 10 =
grid1 = 10 =
grid2 = 10 =
datum1 = 10 = Clarke 1880# 6378249.145# 293.465# 0# 0# 0#
datum2 = 10 =
settings_distance = 2 = 0
settings_unit = 2 = 0
lastwlat = 7 = 30.497539
lastwlon = 7 = -6.756324
c1_x = 7 = 171
c1_y = 7 = 137
c2_x = 7 = 4670
c2_y = 7 = 165

Many Thanks again Jockel for your quick reply.
I downloaded the new CAL files provided by DAERR with Datum = Merchich and made a test with Map Ouarzazate: there are still ~0.01% differences in Latitude and same in Longitude.

I than tried several different Datum resulting in more or less difference.

Finally I re-calîbrated the Map manually and set the Datum = WGS84:
I compared the WP's displayed in TTQV and those produced in the exported PCX5 file and those are almost 100% identical = OK.

Question: do you think this approach by setting Datum = WGS84 is OK (except the fact that I'll have to re-calibrate each Map manually)
or do you think this might create other unexpected problems / errors (i.e. that the WP's created in TTQV and downloaded to GPS are the same, but having discrepancies when navigating live in Morocco) ?

Thanks again for your feed-back / advice and kind regards, Tatchin

OK Jockel, and Thanks again for your reply and recomendations.

I'll proceed as you adviced in your 2nd reply and re-Calibrate the Morocco Map using MERCHICH Datum as recomended by DAERR.

I'll do some live check in Morocco and provide you with feed-back.

I wish you a nice week-end and kind regards, Tatchin