[Aavso-photometry] Differential transformation

[Michael Koppelman]

For us wide-field guys M67 is pretty crowded. I have had good luck 
observing Landolt fields. I made a database and imported it into TheSky 
so I can easily see which fields are transiting.

I wonder how you guys with small FOVs do it. I can get 5 to 15 Landolt 
stars in a single field a lot of times. It would be painful to get only 
2 or 3 stars in a given field.

I do ignore extinction and just observe everything when it is at 45 
degrees, which is where the Landolt fields are for me. This eliminates 
one source of error but drastically restricts what I can observe when.

Cheers,
Michael Koppelman
http://www.lolife.com/astronomy/



On Dec 29, 2004, at 10:09 AM, Chuck Pullen wrote:

> Gier - Note that M67 has been extensively studied and there are a 
> number of stars available in it that should meet the quality test and 
> Arne's concerns.