miketw

3 hours ago, Tiny Clanger said:

Be aware that the greater the magnification , the less time your target spends crossing the field of view of the eyepiece , so the greater your difficulty finding the thing in the 'scope  in the first place , and tracking it once you found it.

Also the greater the magnification, the greater the effect of a relatively cheap mount and tripod in making that view tremble. Magnification is not everything, and the 'toy' scopes you see advertised which boast huge magnifications are in practice very poor instruments.

The general rule of thumb is that you will seldom usefully exceed a magnification equal to the diameter of your telescope aperture  x2 . So for your current 'scope 76mm x2 =152 , 152x is the highest.  Most beginner mounts, scopes and suburban skies are really going to be happier using a mag. around just their diameter in mm.

To work out the magnification of an eyepiece with any 'scope, take the 'scopes focal length  yours is 700 currently) and divide it by the eyepiece mm , so 700 mm 'scope with a 10mm eyepiece is 70x magnification, whilst a 5mm ep would be pushing the limit on an unusually good steady clear night.

What I'm getting at is that excessive magnification will be detrimental to your view through the 'scope, so planning to buy extra eyepieces and a barlow (I presume to increase the mag.) has a practical usable ceiling beyond which you would be wasting money. What that ceiling is depends on which 'scope you buy. Basic plossls (eg skywatcher ones for around £20 to £25 )are OK, but the higher magnification (lower mm) ones are more difficult to look through. It's complicated  ...  Anything below, say, 10mm will be awkward for what is called 'eye relief' and Jaden may have problems getting his eye in exactly the right spot.

A barlow can help with eye relief, so it might make sense to get a middling EP, say a 15mm and a 2x barlow which would have the effect of making 15mm into 7.5mm when conditions allow . Personally though, I'd hold off on the eyepieces and spend the money on the telescope alone, an extra £50 on the basics of the 'scope and its support will get a better instrument. I bet cheap and second hand plossls are all over ebay etc. , and they make ideal gift suggestions for birthdays or to relatives and friends who would like to make a small contribution .

Heather you are like a book! whatever I read from you I'm being educated.

I noticed this in For Sale / Swap

3 hours ago, happy-kat said:

Exit pupil size when very small can cause waggle head as you try to position your eye in the right place. Hold a pair of binoculars inside and turn them around now shine a light (not the sun) through the big end, that little circle of light on the little ends is the exit pupil. That is the size of the image circle to position your eye on, exit pupil. Generally speaking the shorter the eyepiece focal length the smaller the exit pupil gets. Unless you chase magnification I don't think you need to concern about this one.

Eye relief is the distance above the eye peice for positioning the eye to see. A bigger eye relief like 20mm on an eyepiece is good for people who observe using glasses. A twist up or pull up eye cup let's both none or glass wearers observe through an eyepiece.

Usually on the description for an eyepiece is the eye relief measurement, I find 16mm -20mm comfortable to use with or without glasses

Thanks Bright Giant, great to know all this info 👍

1 minute ago, Tiny Clanger said:

Was it maybe a returned item ? I've had a few bargains from 'Amazon Warehouse' when they get something with damaged packaging or a return, well worth a punt if you see something of that kind, as amazon returns policy applies to warehouse deals too , so you can just send it back at their expense if it's no good. keep an eye on the az page, you never know ...

Heather

I'm unsure Heather, funny thing did happen, I was on the phone to Bristol Cameras and I mentioned the cheap price on Amazon, while on the call I posted the link on SGL and by the time I had ended the call the item became unavailable.

9 minutes ago, W0nderste said:

I could be wrong but isn't the astromaster a bird-jones affair, if so it's best avoided.  
I had a similar celestron starsense 127 Lt which I think is the same tube as the astro master and although you could just make out the rings of Saturn it was pretty crap.  It probably needed collimating but Collimating a BJ reflector is not easy.

for what it's worth If tracking is the highest priority then I'd get a virtuosa, or a 2nd hand skywatcher GTi mount with any mid range scope.

i got a GTi goto mount for £150 and a celestron omni 127 SCT for £100 here on SGL. 
so a full goto tracking system that will be far superior to an astromaster

Wow, just had a look at the GTi goto mount and a celestron omni 127 SCT scope, looks like a good setup, Heather is right thinking my budget is around the £200 I also had plans buying an extra eyepieces / Barlow lens totalling to £250

If I could find something like above at a similar price I would be very interested.

Can't thank you all enough for your time and help (especially Heather)

Lot's for me to process, I did find something but have red flags waving at me! If it's to good to be true it's not for you!... what do you think https://www.amazon.co.uk/Celestron-31051-AstroMaster-Reflector-Telescope/dp/B0013Z42AK?th=1

After checking the link it's now showing currently unavailable, It was £139 

After many calls and emails it seems the Skywatcher Heritage 114P Virtuoso will not be back in stock until April, FLO are hoping for late March

I've been looking at other options, one in particular is the Celestron Motor Drive, I believe this item tracks?

Will I be able to fit the motor drive to Jaden's National Geographic Premium 76/700?

I'm slightly up against time as Jaden is now back in hospital, I'm hoping this will be a quick fix until stocks are replenished.

Hoping to have something in place for Jaden return.

Michael

I had no idea GoTo and tracking are two different things, I was under the impression the GoTo tracked as well.

The sky watcher heritage 114p virtuoso looks perfect, would it be better to buy the wifi add-on used with an app on Jaden's iPad or the hand held GoTo device?

Thank you Heather for the link, it's a good price but unfortunately out of stock, where it's in stock the price is double, new stock is expected later February .

My only concern is being a table mount and not on a tripod, Jaden for sure will crash into the table, I'm hoping I can modify his tripod from his National Geographic Premium 76/700

Thank you all so much for your time and knowledge, can't thank you all enough.

Michael & Jaden

Hi all, I'm overwhelmed with your help and can't thank you enough.

Jaden is 10 he is very able doing many things once he has been shown how to, but he does have limits to progress, my reason for the GoTO mount is for him to enjoy himself actually seeing something! 9 out of 10 he will not be seeing anything, when I do get something in focus for him it's priceless seeing his excitement, Tiny Clanger you are spot on!

All observing is done from the garden.

For two years Jaden has show the same excitement viewing the sky, his youtube history is astronomy, stars, planets etc and I feel I'm holding him back from viewing more.

His dream is to see Saturns rings and deep space, the pictures he shows me Saturn is tiny but Jaden seem very happy, I'm not looking for an all singing and dancing telescope, something that is cheap (if possible) bit of an allrounder!

I was hoping to buy something second hand that's affordable on a low budget, didn't realise second hand telescope hold their price, I guess if you have it for two plus years like his (National Geographic Premium 76/700) it's good value for money.

Michael & Jaden 

Greetings all,

 I feel a bit embarrassed asking because so much info is out there, but too much info in the wrong hands is dangerous! so thought I should ask the experts.

My son doesn't stop talking about astronomy, for two years he has been using a basic telescope (National Geographic Premium 76/700) he would use it a lot more if he didn't have to depend on me so much, because of his needs I do need to be with him.

Awhile ago I was offered a second hand Celestron nexstar 4se I was so tempted to buy this because of the GoTo mount, I thought my son could use this on his own, it would also make him feel great using it by himself.

By the time I had done my homework on the 4se the item had been sold, I got so confused what to buy, one telescope led to another then another and so on.

I'm sure this is a very dull question to you all, can I ask your advice please, the GoTo mount is a must because of the simplicity to track and follow which my son has troubles doing, my son is a different boy when he is viewing the sky, if it wasn't for me saying we need to go indoors he would be out all night! even with heavy cloud cover he will be looking through the telescope.

I now have a far less budget then before (furloughed) just want to make sure what money I do spend it's not wasted.

I had no idea how technical and advanced telescopes are, any info pointing me in the right direction will make my son very happy.

My son name is Jaden and he says hello and thank you.