Observing during daylight, observation de jour

Spectroscopy of eps aur in these times is a tought task. I've been able to follow esp aur during end of may and this early June with a higher pier. I've started capture during daylight, with manual autoguiding, having still 40mm before epsaur set behing neirborough houses. My observatory is on the eastern slope of an urban hill and the only possibility for me to do spectra of epsaur is to begin capture during daylight. The difficulty is to spot it. I used a goto mount but it's not a perfect method as i used the moon or the sun for initial pointing. Venus is more helpful if visible. If the sky is coronal it is quite more easy. The spectaculars 2D spectrums are mixed with solar spectrum who as to be removed during treatment. Last day it was a real challenge, it will be more difficult every day for my latitude.

Here you'll find comparison of four 2D spectrums from May, 23 to June 4. Remark the strengthen of the daylight spectra, and the fading of eps aur spectra as the observations began during daylight.

comparaison des quatre derniers spectres de eps aur, du 23 mai au 4 juin. Remarquez le renforcement du spectre solaire et l'affaiblissement de celui de eps aur. Mais je n'ai pas le choix. Mon observatoire donnant sur l'est il me faut à quelques jour de l'opposition solaire réaliser des observations de jour durant la phase du brightening, unique, de l'eclipse. Le pointage est délicat, mode goto avec une initialisation sur la lune, le soleil ou venus si visible et l'autoguidage devenant impossible quand il fait trop jour.

 Les spectres obtenus :

C'est cohérent. Les raies telluriques sont très présentes du fait de la faible hauteur de l'astre mais la répétabilité du spectre est bonne. Remarquez l'absence d'évolution du profil Ha durant cette phase tres particulière de l'éclipse.

Tellurics are very strong as eps aur is at high air mass elevation, low altitude. Spectrums are the same, from the darkest backgrounf to the brighter. It seems that there is no evolution of the Ha profile during this mid eclips phase.