Re: [APML]: Color film/urban site

[ipper@juno.com (C B IPPER)]

On Fri, 11 Oct 1996 13:43:00 -0600 (MDT) Dan  Baldwin
<baldwin@ixtlan.colorado.edu> writes:
>
>Hi--
>
>       I have been an astro photography fool this week with
>our ver clear skies-- My photos are all well focused and
>guided well (thanks for everyones help in figuring out
>my ST4 problems)-- My problem now seems to be my suburban
>setting and I'm wondering how to proceed from here. I know
>that Steve Bell has achieved some good photos from a light
>polluted location using hypered TP-- my question is can good
>photos of dim objects using color film be achieved from a 
>moderatly light polluted site ?  These are my results so far,
>if someone could please advise me , I would greatly appreciate it.
>I used four different films so far  1) Unhypered PPF 400 (UPP),
>2) Hypered PPF 400 (HPP), 3) Unhypered Fuji 800 (UF8) and
>4) Hypered Fuji 400 (HF4)-- I used my C11 at either f/10 or
>at f/5.6 with a reducer. I am only judging the result as
>good,fair,poor,etc--I realize that this is a crude way to
>describe a photo. Poor refers to  lack of faint structure
>ie spiral arms of M51 due either to under exposure or lack
>of contrast between object and light polluted background.
>
>Object                 Film   f/ratio  exposure        result
>
>M51                    HF4             f/10      
>60min          fair (can see spiral arms)
>
>M82            HF4             f/10     
60min           good
>
>M27                    UF8             f/10      
>60min          fair-good
>
>M17                    UF8     f/10     
60min           fair-good
>
>M31                    UF8             f/10      
>60min          fair-poor (some dark lanes)
>
>M31                    HPP             f/5.6     25min     
>worse than above
>                                                                                       
>(lots

>of "fog",no structure)
>
>M31                    HPP             f/5.6     
>45min          same as above
>
>M42                    UF8             f/10      
>45min          good-excellent (thankfully !)
>
>NGC 7531 (?) UF8       f/10      90min         fair-poor 
>(no spiral structure)
>
>M33                    UPP             f/10      
>90min          poor (faint spiral structure)   
>
>M33                    HPP             f/5.6     
>40min          same as above 
>
>M1                     UPP             f/10      
>90min          fair-good (can see red filaments)
>
>M1                     HPP             f/5.6     
>25min          poor (no filaments, lot of fog)
>
>
>As I'm compiling this, I can see that I still need to make some 
>comparisons,
>like UPP and HPP for M42 and M51 and also HF4 and UF8 for M33.
>
>Should I give up on getting a good color photo of M33 from my suburban 
>site ???
>Do these results seem typical ? Any advice (please !) ?
>
>Thanks,
>Dan Baldwin
>
>
>
>
>
>
Hi Dan,
  Just for an example use your unhypered Fuji 800 on M-51 in a dark sky
at  f/11 for 120 minutes.    This works great on a C-14.   Carl Faulkner