I bought myself a Orion XT10g goto telescope a few months ago. Really been enjoying the scope but i have a few questions.
First questions is using filters to look at Saturn. I got a Baader 6 colour filter set with, Blue, Dark Blue, Orange, Red, Orange and Green. From what i have read online is that certain colours will show the rings better or other parts of the planet. I tried them out and all it really did was turn the planet into another colour with no difference to detail. When using no filter there isn't much detail in the plant, it's really just a monocolour image. nothing like in the reviews in this one. http://orionskyquesttelescopereviews...om/xt10/xt10g/
I also find that i have to get some serious magnification going to try and get up close to Saturn. I also got myself a 8mm and 5mm Orion Stratus eyepeice and a 2x Veleview Barlow. from what i see is the rings and the planet, but you cant make out the gaps in the rings. Unfortunately i have not got the set up to take photos. Also looking at mars, others talk about using a 6" or 8" telescope and being able to see the poles and some detail in mars. With my highest magnification all i see is a red dot. Am i doing something wrong or are people talking B.S.
I believe i have got my collimation down and don't thing its a problem, yet i still get some flairs (I hope that's the right terminology) from Alpha Centauri. With the 5mm and 2x Barlow it comes to x480 Mag with a 13% moon filter (only filter i have that reduces glare) on Alpha Centauri i can comfortably make out two light sources.
Am i asking too much from my telescope or am i doing something wrong?
Assuming your collimation is okay, several issues can stop you getting sharp images.
a. The atmosphere - are stars twinkling overhead and near where the planet is? If so, forget about getting anything sharp.
b. Are you viewing over your own house or neighbour's houses, where they are giving off heat from heaters or airconditioners? That'll muck up the image.
c. Has your telescope cooled down enough? If it hasn't, don't expect much.
I used to live in the middle of suburbia surrounded by neighbours, and being aware of the latter points could regularly view at 300X, and a few times a year at 400X.
I moved to a bigger property, with few neighbours close by, but nearer our bay and next to a gully. Now I struggle getting a decent image at 300X. So that where one lives has something to do with it.
The idea with magnification is to work your way up - start at 200X, if the image is good, go to 250X or higher, if the image is still good, go higher. And so on till you get a lousy image, and then go back to the previous lower magnification.
Some people think colour filters are a waste of time, some love them. I certainly like using a red filter on Mars all the time, and sometimes use a yellow filter on Jupiter and Saturn to enhance cloud contrast on the discs. Though I've never found any use for blue filters.
Not sure about your flare problem. At low power, everything flares in my images because I have astigmatism in my eyes. But it mostly disappears at high power. Flaring can occur from poor collimation.
Regards,
Renato
Hi Leigh, When the seeing is good you should be able to see the
Cassini division in Saturn's rings; I can with my 8" and 10" Newts.
Mars is a difficult object to observe. When it is close to us, and the seeing is good, quite a lot of detail can be resolved, and the polar cap will be
very obvious. When it is further from us, and/or the seeing is average, almost nothing can be discerned with moderate sized scopes. Patience
is a virtue with Mars.
If you go to the Lumicon web site you can print out a copy of their
listing of precisely what each type and colour of filter is good for.
Something is wrong if you need 480x to see that Alpha Cent. is a
double, my 8" will separate them at a far lower power than that.
Are any objects absolutely pin sharp in your scope? At powers up to
around 150x the moon should be stunningly sharp in a 10"scope.
raymo
It is pretty hard to see detail on Mars right now: the disc is too small. However, you should have no problem seeing at least the Cassini division on Saturn, even at low power (less than 100x), and even when seeing is less than perfect (most of the time!). (I can see Cassini with a 70mm scope pretty well every time I look.)
My guess is that your collimation is not as good as it could be.
In terms of magnification, 200x is more than enough to see heaps of detail on the planets: but you cant expect Hubble telescope images!
Are the edges of the planet and the ring sharp or slightly fuzzy? When you increase magnification you will get to a point, even with a well-collimated scope, where no more detail is possible, and things begin to get fuzzy. That is the point where you decrease magnification.
If collimation is spot on, the image is not boiling due to poor seeing, and you still can't see the Cassini division, then there may be a problem with your optics...
I would also suggest that you work on seeing as much as possible without filters. Colour filters enable subtle enhancement of certain types of features, but if you haven't spent much time "training" your eye it is not likely you will notice a great deal of difference at first: especially on Mars when the disc is less than 6 arc seconds across.
With planetary viewing, the more you look the more you see...
I currently live in a medium populated area near East Maitland. I am looking over a neighbors house but don't think that will have an impact as they have no aircons or other factors that will effect. I dont get any boiling affect on the image even at the x480 mag and haven't seen any of that affect yet.
I still cant see the cassini division its just one big ring. I have heard someone say who has the same telescope as me that Saturn is very bright, which from looking at photos online it does confirm what i am seeing. Can this be a factor that could cause the loss in detail?
I believe my collimation is good, i get the laser dead center of the black ring in the Primary Mirror and back again on the target on the collimation device.
The only flair i do mainly get is off Alpha C, anything else i don't really get any. Looking at the jewl box all the stars are clear and crisp.
Even at the x480 Mag Mars is still just a very small dot. I am pretty sure it is Mars as i use it in the bright start alignment, then when the scope asks if a star is what it is says its 100% on. (it used to be slightly off but i think that was got to do with the angle that the base was on due to my back yard not being very level. Sorted it by attaching some leveling legs).
I have attached a photo for roughly what i see at x480 Mag from http://www.risahorowitz.com/projects...gingsaturn.htm at this mag i am getting some blurring at the edges of the planet. The difference from this image to what i am seeing is, mine is way brighter and cant see cassini div. Even at lower mag i still can see much detail.
I will endeavor to take it out to my clubs next observatory night.
Also thanks Raymo for the filter reference, will be printing that one out.
At 480x Mars should be more than a small dot, It's disc should be plainly discernible. When you have done your initial alignment, go to a couple of targets to make sure that the go to is reasonably accurate, and then select Mars. At least then you'll know for sure whether you are looking at Mars or not.
raymo
Hi Leigh, Maybe you expectations are a little higher than the telescope can produce. This is a good thing because it gives you an excuse to upgrade to something bigger. Aperture fever is a very real condition & a visit to your nearest professional Astronomy shop is the only cure!
Hi Leigh!
You have some very good questions there. I will answer a few of them out of order.
Firstly Mars. Mars is well past opposition (which is the best time for viewing it) as a result it is very small. Of all the outer planets, Mars is the one that has the greatest variability in its apparent size during its cycle. At a good opposition it is easy to pick out the ice caps and other features even at only moderate magnification. But right at the moment it is small and as it gets lower in the evening sky atmospherics affect it more.
Saturn. The Cassini division is the large gap in the rings and should be capable of being seen at moderate power given reasonable atmospheric conditions. Again as it gets lower in the west these become harder to see. The bands on Saturn are very subtle. Filters can help a bit to increase the contrast but they will still be subtle. It is also well past opposition now so it is a small target.
The good news on planets is that Jupiter is approaching opposition, a few months to go, I think the actual date is mid Febuarary 2015, bit its will become more prominent as the months tick by.
Alpha Centauri. Anywhere over 100x should be sufficient to separate the A and B components of Alpha Centauri. Again it is fairly low in the evening sky so poor atmosphere can make this harder. As for the flairs. All bright stars will display some degree this. If it is even around the star its is not collimation related. Poor collimation effects on the image are often poorly understood. A poorly collimated newtonian will have stars in the centre of the field displaying some degree of coma. Note the collimation doesn't cause the coma, only cause it to be visible in the centre of the field. This guide to collimation has quite a good sample of optical issues at the bottom of the document http://www.astro-baby.com/collimatio...on%20guide.htm . You willl note that coma exhibits as stars appearing as little comets.
Thanks heaps Malcolm, that guide is really great. There is a lot more detail in it compared to most YouTube videos of some dude just going through the very basics. I did notice in the software that came with the telescope, Starry Night, showed Jupiter visible in mid to late November but that's later on at night, midnight to 2am. I can't wait to see it.
I wish Pinwheel . I have dropped the word to get a bigger one to the Minister for War and Finance, and i got the look, lol. Maybe in a a year or two.
. I have dropped the word to get a bigger one to the Minister for War and Finance, and i got the look, lol. Maybe in a a year or two.
