Re: V image fainter than I

[droege@snapmail.us]

This is something for which we have data.  Lots of data.  We have been
keeping the make_list.out files for two years.  These record the number of
detections in the V and I lines.

Doing a Droege special statistical analysis (taking 3 reandom line pairs
from the first make_list.out file in tr26) I get a ratio of I detections
to V detections of 2.10.  If any of you are inclined, a small script
should be able to get the ratio for the entire data base.  I would be very
surprised if it were out of the range of 1.9 to 2.3.

It would be more pleasing to my sense of beauty if the detections were
about the same and the range was about the same.

Tom Droege


> I like the idea of longer V exposures so that you get roughly the same
> number of stars in each filter.
>
> Michael
>
> On Mar 18, 2005, at 4:55 PM, droege@snapmail.us wrote:
>
>> My thinking is to try to go a little fainter with the present setup.
>> Let's say increase the exposure to 200 seconds.  This will work fine on
>> the V camera.  The I camera will have a sky background problem at this
>> exposure.  Further, a lot of stars that are not saturated in V will be
>> saturated in I so we will lose bright stars.  I admit, not a big loss
>> since these are well measured.
>>
>> By stopping down the I camera the sky background will be reduced and it
>> will better match the V camera through the range.
>>
>> Tom Droege
>
>
>