Posts Made By: bill warden

relatively new to this
so forgive the newbie comments.
loved the red dot finder on my celestron nexstar 114.
broke the piggy bank and got a nexstar 8
which comes with a 9x50 finder scope.

my small red dot finder
rarely lost alignment
and was easier to align (with 2 screws).
i really don't like the finder scope
as it seems like i'm always bumping it
and knocking it out of alignment
(just taking off the lense caps does it some times)
moreover i find it difficult
to realign in 2 dimensions with 3 different screws.

am i missing something here?
any hints on keeping the finderscope better aligned?
the screws are tight.
(i note that many in this forum like a finderscope and a red dot or telerad)


ok here's the trick:
lamenting the loss of my red dot finder
i was struggling to find a star
(had to crouch to see thru finder scope)
using non-dominant eye in finder scope
with dominant eye open to find star which wasn't even in the finder scope field...
voila
the cross hairs of the finderscope
were superimposed on the star
even though the star wasn't yet in the finderscope field!
i slewed the telescope to get the star in the finderscope
and suddenly i see a second (brighter image) of the star
in the finder scope moving more rapidly
and in the opposite direction (right to left)
as the first image.
i lined the finder scope image on the cross hairs
and was all set.

holy corpus callosum!
my brain superimposed the crosshairs from the eye with the crosshairs, but no star onto the field of the eye with the star but no crosshairs.

is this the way one's supposed to use a finderscope
or just a fancy parlor trick?

in any event it seems to me that the finderscope can be used like a telerad.

maybe i'll give the finderscope a few more tries
but i still like the red dot better.

thanks

bill

ps can anyone suggest a good forum for newbie comments like this?

i recently tried a a denk II with my celestron nexstar 8 GPS (SCT) using the star sweeper and 19 mm antares w70 eyepieces and noticed that i could not get stars at the periphery and stars in the center in focus at the same time.

after this i checked out the view using a 24 mm panoptic (monocular) and indeed noticed i could not focus edges and center at the same time (especially noticable viewing the moon or big clusters)

i'm ruined

is anyone else troubled by this?
i was wondering if one of the f/6.3 field corrector/flatteners would help.

could it be a collimation issue? it seems ok to me. also, i would think collimation would be more of a difference from one side of the field to another, rather than center to edge.

any suggestions would be appreciated.

thanks

bill

hello

can anyone suggest a 1.25" eyepiece in the 25-26 mm range
with a moderately wide field 50-65 degrees?

for use in a celestron nexstar 8 (F10 SCT) & binoviewer with with doubler/reducer switch

thanks

bill

hiya

will a meade 24.5 mm SWA (67 degree apparent FOV) have a problem with vingetting if i use a .7x focal reducer in my 8" f10 SCT?

using nexstar 8 gps, denk II power X switch with star sweeper

thanks

bill

aww come on
someone leave the 2" thread for a minute and take a look here

any comments on non-flat SCT focal plane and wide field views

wups
just realized i never posted my follow up
field flattener did not correct the problem i was having.
got a set of bob's knobs and made an artificial star...
voila, moon is in focus across the entire field
in binoviewer with starsweeper and panoptic straight thru

i was surprised that it was a collimation issue

sorry for the lag in follow up

thanks for all your replies

bill

i'm sort of a newbie
but i'll share my experience
the 2x multiplier in my system is more like 2.6x
others have reported 2.2x

the result of 2.6x is that it multiplied my EP mag more than local seeing conditions usually tolerate (i picked an EP based on 2x mag).

if you really know what mags you like for planetary viewing get the bino first with a starter set of EPs, measure your actual magnification, then fine tune to your high power sweet spot with a high end set.

i have a pair of antares 19 mm w70's if you're interested in a starter set before "the price is no object" phase

i know it sounds weird
but you might want to check your colimation

i noticed the same problem
when i went to very wide fields
with a 24 mm pan or wide binoviewer
using my SCT

stars were points to the edge after colimation

i'm a bit of a newb, so take it with a grain of salt
but you might want to check it before getting too riled up