From: Mark Gaffney <markgaffney@me.com>
Date: March 7, 2010 10:47:14 PM MST
To: Astro_IIDC@yahoogroups.com
Subject: Re: [Astro_IIDC] New DSO Images
Sorry about the spelling in that last message-I made a few mistakes using the iPod...I mean I`m hoping the go-to will find the subjects better automatically with a good 3 star alignment as described. My polar alignment has still to be verified as OK of course. Eta Carinae may need some guiding to stay still enough for the longer exposure time needed for just a B/W image which I`m planning at present..?
Mark.
On 08/03/2010, at 4:30 PM, Mark Gaffney wrote:
Hi Milton, Thinking about it I should be able to line up the finder with a bright star fairly easily given the FOV at 1600 x1200 pixels & 0.3 reduction. Where I expect troubles is finding The Trpezium in the finder! Unless the wide field of view is very forgiving as to placement with a better 3 star alignment using stars in the noth-west & south east? At this stage I'm stating to think about mew subjects further to the east or possibly in the south. None I'm finding have the compatitive interest factor combined with short exposure times of M 42.Last night I looked at the Eta Carinae nebula for instance for suitability but it seems a quite difficult subject!?
Mark.
Sent from my iPod
On 08/03/2010, at 10:34 AM, Mark Gaffney <markgaffney@me.com> wrote:
Hi Milton,
The finder is well lined up with the centre of the eyepiece- which I need initially to do my 3 star (or what-ever) alignment. I leave it out under the cover now all set-up. The problem here is that no land object at greater distance than about 80 metres (for the sign) or perhaps 100 metres (for some trees down the front) is visible any more. We used to be able to see the local television/ mobile phone etc. antenna some miles away but trees have grown up all round. I guess if the spotlight method won`t work, I`ll have to find a star with 4 x 4 binning (to start with) then line up the finder with that, in the absence of the moon...There dosen`t seem much prospect of doing anything at present with the weather here though..
Mark.
On 08/03/2010, at 8:52 AM, Milton Aupperle wrote:
Hi Mark;
On 7-Mar-10, at 2:27 PM, Mark Gaffney wrote:
> They`re great Milton!
> I have a Hubble image of the Black Eye Galaxy on a new app on my
> iPod Touch. It almost seems to be turning slowly!
> With my imaging I`ll probably have to use my spotlight on the
> shipping container method for aligning the finder with the camera`s
> offset. The moon is rising too late now to do it for M 42. I checked
> the spotlight solution (shining it on the small sign on the
> container about 80 metres distant) from the scope the other night in
> a brief non rainy period & it can be seen alright. Would 80 metres
> be OK to give such a finder alignment do you think?
You will get some error because they aren't far enough away to be
parallel. I use construction cranes on the other side of the valley 2+
km away initially at dusk, and then center on a nice bright star to
fine tune.
Unless your being really rough with your scope, you should not need to
align the finder each time, especially since your primarily shooting
with a 0.3x focal reducer.
I only wind up doing this if I have dismantled the scope for
transport.
Milton Aupperle