fixed scope viewing time. eg(saturn)

[leenewtoastro]

if i buy a fixed scope and point to saturn how long will it stay in the eyepiece?

how do scopes lend them selves to manual tracking? was thinking of the skywatcher skyliner 200p dob?

[FraserClarke]

A minute or two only. Of course, the idea with a dob such as this is that you nudge it gently to follow the object as it drifts out of the field of view. It's pretty easy once you get the hang of it

For this particular case (200p dob), if you have say a standard 20mm Plossl-type eyepiece in (apparent field of view ~60 degrees; to make the maths easy!), you have a field of view of 60 / (1200/20) = 1 degree. Earth rotates at 15 degrees/hour, so you have ~1/15 hours = 4 minutes for Saturn to go from one side of the field of view to the other.

[leenewtoastro]

thats much much more than i imagined. yipee

[roboticsound]

But I suppose that 4 minutes assumes that Saturn was placed right at the side of the FOV so if it was place in the centre then it would be in the FOV for a couple of minutes.

[WayBig]

Although if you crank up the magnification it will move out of the field more quickly. You'll probably get a 10pm ep with the scope, so will have roughly half the time above... Though it seems like less to me

[leenewtoastro]

tbf i was thinking 10-20secs

[Stephen]

On my 200P Dob with the 880NC webcam (approx 6mm?) I get it in view for approximately 50 seconds.

[leenewtoastro]

how does a nudge actually pan out?

i.e 2 axis are involved! ?????

a "nudge" can only move 1 ?

[Stephen]

how does a nudge actually pan out?

i.e 2 axis are involved! ?????

a "nudge" can only move 1 ?

Indeed, each nudge moves the target down (or up, depends on which way in the sky you are looking) a smidge. I would say on my setup I've got 3 nudges before I have to move the scope up (or down) to get it back into view.

[leenewtoastro]

is a nudge a measured science/feature of the scope or a nudge of the hand/finger.

lol you may but you never know lol

[Stephen]

is a nudge a measured science/feature of the scope or a nudge of the hand/finger.

lol you may but you never know lol

There's certainly no science in mine, quick humph with the shoulder and let the target flip to the other side of the view Locking the scope so it can't travel up/down easily helps (on the 200P you can tighten or slacken one of the handles to adjust moveability of the tube up/down.)

[leenewtoastro]

thx

anyone know how big it is height and base width?

i see lots of dims of it astrologically but not overall

[Stephen]

Off the top of my head it's about 50cm wide by 150cm tall fully assembled - someone might be able to give a more accurate figure

[leenewtoastro]

can't find one locally arrrgghhhh. birmingham/tamworth! ?

[Stephen]

You mean second hand? New, FLO do them for £275

Dobsonians - Skywatcher Skyliner 200P Dobsonian

I also found this - http://www.astrobuysell.com/uk/propview.php?view=39146 but not much detail on it

[leenewtoastro]

pref new and around birmingham/tamworth/nottingham central corridor