Re: [APML] Film and OAG Questions

[Duncan <dmunro@sfu.ca>]

What star diagonal? If you are using a NEG it will not focus at the 
guiding EP and the focal plane unless you have a 35mm camera attached to 
it via a standard T-adapter, and you are using a a EP only or an EP and 
short Barlow combo. Are you using a NEG or CEG?

cheers


Duncan


GARY HATFIELD wrote:

> Thanks Bill, Duncan, and Chris!  The sky cleared last night so I gave 
> it a shot.  I could not get it to focus using the star diagonal and 2X 
> Shorty barlow.  I'm going to check it out in the day to see if I can 
> figure it out.  I guess I'll just have to deal with the 3X Prism 
> diagonal for now.  As for the Fuji film, it's called Fujicolor 
> Press DX 800 ISO.  Since the sky was clear I thought I'd give it a 
> test.  I took various exposures with my 55mm lens @ f/4 and a few 
> prime focus shots through my 80mm f/6 achromat.  I should have them 
> back by Wednesday and will post my results.
>  
> Gary
>
>     ----- Original Message -----
>     *From:* Chris Schur <mailto:cschur@therim.com>
>     *To:* Discussion of Film Astrophotography
>     <mailto:astro-photo@seds.org>
>     *Sent:* Monday, October 11, 2004 8:46 AM
>     *Subject:* RE: [APML] Film and OAG Questions
>
>     Gary, welcome to the world of off axis pain and suffering.  I use
>     a 2x barlow for my visual guiding, 3x is too much and makes the
>     stars much too faint.  Just remember to calculate your maxium
>     guiding tolerance and be able to see it clearly in the guiding
>     eyepiece is the key.  so if your tolerance is 5 arcsec, know what
>     that looks like by spliting doubles in the guiding eyepeice.  Try
>     epsilon lyra for example.
>      
>     Chris
>
>         -----Original Message-----
>         *From:* astro-photo-bounces@seds.org
>         [mailto:astro-photo-bounces@seds.org]*On Behalf Of *GARY HATFIELD
>         *Sent:* Saturday, October 09, 2004 6:17 PM
>         *To:* APML
>         *Subject:* [APML] Film and OAG Questions
>
>         Hello,
>             I bought a roll of Fuji Superia 800 and was shooting with
>         it at a festival today.  I didn't use all 36 exposures and was
>         wondering if this film is any good for astrophotography.  I've
>         forgotten what it actually said on the film cannister itself,
>         but on the film tube it came in it reads--Fuji Superia
>         CZ135-36 800 ISO.  Just wondering if it's worth my time to
>         finish the roll under the stars or not.
>             I have a Lumicon 2" Easy Guider and the (Lumicon)
>         recommended 3X Prism Diagonal.  I guide with a 10mm
>         illuminated reticle.  I'm using a 480mm f/6 80mm achromat.  My
>         problem is not so much in finding a guidestar (although that
>         is a challenge at times), but having one bright enough that I
>         can actually see well enough to guide with, without having
>         to use averted vision.  Is there a reason for using a prism
>         instead of a star diagonal?  I realize having a 3X
>         magnification is going to make the guiding easier and more
>         accurate, but would I get brighter guide stars by using a star
>         diagonal and 2X barlow?  Would I be able to focus the
>         guidestar with this set-up?  The sky here is socked in or I
>         would try it out.  I'd appreciate any thoughts or knowledge
>         anyone might bestow upon me.
>          
>         Gary 
>
>     _______________________________________________
>     Astro-Photo mailing list
>     Astro-Photo@seds.org
>     http://seds.org/mailman/listinfo/astro-photo
>
>------------------------------------------------------------------------
>
>_______________________________________________
>Astro-Photo mailing list
>Astro-Photo@seds.org
>http://seds.org/mailman/listinfo/astro-photo
>  
>

_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo