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Nexstar 8se alignment issues.


Guest Meteoriot
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Guest Meteoriot

Hi all. I finally cured my scope firmware problem and took it out tonight.

I also managed to get a successful alignment for the first time! Progress at at last yay!

The alignment was slightly out unfortunately despite my best efforts to center Rigel, Vega and a third star unknown to me.

I am wondering if the time or location was slightly out. The nearest city stored in the celestron handcontroller is birmingham and I am in Mansfield
so I am wondering if I should enter the coodinates or does it not matter
too much? Perhaps the time was out by a minute or so, I am not sure.
How accurate does it need to be please? Any help is greatly appreciated as always :)

 

Richard

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The higher the magnification you use the better it is if more accurately aligned. However - with average seeing allowing mostly 180x to 200x mag then degrees and mins should be enough. Birmingham's a coupla degrees away so I would choose to enter the coords and time manually unless using gps. :)


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Yeah is recommend you use google earth am find the exact spot you observe from and drop a pin and it tells you the lat long if that location and then input the one exactly an then polar align (if using an EQ mount) and the star align and make finer adjustments to centre each alignment star

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Guest Meteoriot

That'll be the problem then I reckon.

I think I can only afford a dew shield. Any idea how long (on average) that would give me per session and how can I combat it? Someone said just tilt the scope downward for a while until it clears but I'm not sure how effective this will be.

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How long is a peice of string?


 


The dew problems depends on how much mositure is in the air.


 


A dew sheild will not stop dew from forming but it will prolong dew forming on the optics.


 


It also doubles up as a LP sheild.


 


The only way to combat it is with dew heater strips and controller units.


Edited by Daz Type-R
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Guest Meteoriot
How long is a peice of string?

The dew problems depends on how much mositure is in the air.

A dew sheild will not stop dew from forming but it will prolong dew forming on the optics.

It also doubles up as a LP sheild.

The only way to combat it is with dew heater strips and controller units.

Of course. Conditions vary and obviously buying a dew shield with not change the weather. However, the same conditions would apply with or without the dew shield so I thought there might be a percentage, or average, or rule of thumb or or even just a guesstimate! No harm in asking lol.

How long is a piece of string?

About 13 letters long! :)

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Well - you'll notice it in the finder just before the eyepiece - once that's misted the objective won't be far behind - corrector plates also attract dew like a magnet - even a dew shield seems to have little effect.


 


What the shield really does is it holds back the dew when it's cold and there's a small temperature gradient between the glass (or mirror) and the air - but once there's moisture in the air it will form regardless unless you have a dew heater strip. Once it gets heavy with dew - even the heat strips won't hold it off. So loosely speaking you could say a dew shield works all the time untill the air goes moist.


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Guest Meteoriot

Thanks for that. I would be much worse off without your help. It's really appreciated. I'm just a bit reluctant to spend any more money at the moment as its already cost me a small fortune :)

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The controller does let you vary the heat going into the optics, I myself would not use it straight off the battery but that's me, you want your optics just a degree or so above the dew point, any more than that and you are just chucking warm air into your tube/optics whatever you have a heater strip attached too.  The controller (depending on which one you have) also allows you to plug in more than one heater strip.


 


I myself have 5, 1 on the secondary mirror, 2 on the finder scope, 1 on the ep and 1 on the Telrad, I have spent just about 12 hours outside in a field near a lake at  EMS1, after a few hours some people were packing up due to the dew, I was going all night long !!


 


Unfortunately glass and metal attract dew like it's going out of fashion, dew controllers / heaters are all part and parcel of the hobby.


 


I remember one chap called Steve just brought his new (and expensive) GOTO mount and scope to the Sawley dark site, after about 2 hours he had to pack up due to the dew, that made his kit the most expensive piece of kit that could not be used.


 


There are expensive options to dew control and there are cheap options to dew controller.


 


Which route you take is up to you, but if you want to be out all night, then a dew system of some sort is a must.


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Guest Meteoriot
The controller does let you vary the heat going into the optics, I myself would not use it straight off the battery but that's me, you want your optics just a degree or so above the dew point, any more than that and you are just chucking warm air into your tube/optics whatever you have a heater strip attached too. The controller (depending on which one you have) also allows you to plug in more than one heater strip.

I myself have 5, 1 on the secondary mirror, 2 on the finder scope, 1 on the ep and 1 on the Telrad, I have spent just about 12 hours outside in a field near a lake at EMS1, after a few hours some people were packing up due to the dew, I was going all night long !!

Unfortunately glass and metal attract dew like it's going out of fashion, dew controllers / heaters are all part and parcel of the hobby.

I remember one chap called Steve just brought his new (and expensive) GOTO mount and scope to the Sawley dark site, after about 2 hours he had to pack up due to the dew, that made his kit the most expensive piece of kit that could not be used.

There are expensive options to dew control and there are cheap options to dew controller.

Which route you take is up to you, but if you want to be out all night, then a dew system of some sort is a must.

Super!

Thank a lot :)

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I would recommend using a controller, as it can be real expensive if it overheats. I had a controller fail on my Telrad heater, and it's only a tiddy 3 watt resistor, it melted plastic.


 


That and you only need it just above ambient, so you can turn it down for warmer nights, that will let your battery last longer too.


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  • 3 months later...
Guest Meteoriot

No probs, if you want to see a dew heater system your more than welcome to pop over, your only up the road from me?

Thanks for the offer. I think I certainly need some assistance. I think my problem is that I want to jump straight into the deep end with everything. I really appreciate the time taken to assist. Thanks again!

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