Apache Point Observatory
                      3.5m Telescope Night Log
                      Saturday, April 18, 2026

PROG  PI ASTRONOMER      OBSERVER(S) 
--------------------------------------------------------------------
NM01  A.Menchaca        A.Menchaca,M.Prescott 
NM03  K.Sanderson       K.Sanderson           

                         ON-SKY
PROG  INSTRUMENT     START   FINISH
--------------------------------------------------------------------
NM01  KOSMOS         20:02   01:08   
NM03  KOSMOS         01:10   05:32

   PROG       SCHEDULED      WEATH     EQUIP     OBS     NOT USED
 I/ROW/DTN  START  FINISH   D    B    D    B    D    B    D    B
-----------------------------------------------------------------
NM01/R      19:44  01:10    0    0    0    0   3.6  1.8   0    0
NM03/R      01:10  06:20    0    0    0    0   5.2  0.0   0    0

note: scheduled times listed include instrument change time

              ------------- ACTIVITY LOG --------------
Observing Specialist: H.Abbot

A cold airmass came in with high winds right before sunset, which caused terrible seeing at the start of the night. Otherwise clear night with no telescope issues.

Echelle ran into an error running the IOL script in the morning, specifically the Wavecal (ThAr) exposure. Error message:
2026-04-19 11:18:40 APO.Harry 309 echelle f text="error from motor controller: '\x15[Invalid Command]\r>'"
calfilter Open failed: error from motor controller: '\x15[Invalid Command]\r>'

Changed Cal Filter from Blue to Open in the instrument window and that worked fine, so I started the script again and it ran with no issues.

                    ------- FAILURE LOG -------

              FAILURE MODE     TIME
PROG   INSTR     TI/SHU    START  FINISH  DESCRIPTION
----------------------------------------------------------------------


            ---------------- FOCUS LOG ---------------
Time  Instrument  Focus     Az  El  Temp Strc Prim  Sec  Air  filt  FWHM
--------------------------------------------------------------------------
 20:31 kimage   253(  656)  37  63   1.4  6.5  7.0  7.9  2.4   --  4.13
 22:53 kimage   428(  557)   8  55   0.8  0.5  1.9  0.7  0.6   --  3.80
 01:23 kosmos   528(  619)  -6  50  -0.1 -0.3  0.2 -0.5 -0.2   --  1.80


               ------------- WEATHER LOG ----------------

                                   Wind                      Precip.or
     Time   Temp F Dewp F  MPH  Direction    Dust    Sky    Conditions
    ------------------------------------------------------------------
	
     16:00    52    22     11   246  (WSW)   1555    clear     none 
     17:00    52    21      9   261    (W)   1878    clear     none 
     18:00    47    17      6   109  (ESE)    912    clear     none 
     19:00    40    17     19    78  (ENE)    773    clear     none 
     20:00    35    15     21    74  (ENE)    898    clear     none 
     21:00    34    13     23    69  (ENE)    777    clear     none 
     22:00    34    12     26    71  (ENE)    908    clear     none 
     23:00    33    12     22    74  (ENE)   1370    clear     none 
     00:00    32    12     18    84    (E)   1705    clear     none 
     01:00    32    13     16    85    (E)   1932    clear     none 
     02:00    34    14     11    97    (E)   1792    clear     none 
     03:00    38    11     18   127   (SE)   2033    clear     none 
     04:00    40    10     16   143   (SE)   1734    clear     none 
     05:00    41    10     16   150  (SSE)   1690    clear     none 
     06:00    41     5     18   137   (SE)   1795    clear     none 

     Note: the wind was coming from the azimuth listed.
     The convention used is north=0 degrees, east=90 degrees.
     The dust count is particles > 1u per 0.1 cubic feet.

              ----------  TELESCOPE SOFTWARE  ----------

Current TCC version: 1.4.2
Current HUB version: v20171231_01
Current TUI version: 3.1.8