Dear All
Despite the crappy moon I had a look through my new toy tonight. I got in about 30 mins of viewing before the clouds won.
I set up the scope this afternoon and had a look at some distant trees. There is a tiny amount of blue fringe using an 8mm teleview plossl but nothing at all through the supplied 10mm eyepiece. (that looks like a Meade wide angle series 4000)
Tonight I aligned first on centaurus A through the clouds. The double is perfectly clean split with a 24.5mm eyepiece and also with the 10mm. I wasn't able to make out any diffraction rings as the clouds were getting thicker.
I then aimed at spica. It was in the clouds but also showed no false colour.
By now the entire sky to the west was clouded so I aimed a Jupiter in the east. Using the 10mm eyepiece it was lovely and clear with no false colour.
I wasn't able to assess whether the field is flat photographically because of the cloud but the stars seemed to have the same focus at the edge of my 24.5mm eyepiece to the centre.
I 'm looking forward to trying the scope out some more but will need the clouds to go.
Got to agree with Alex.. also now that you've had a chance to play with it, how do you find the overall build quality of it? ie: fit and finish?
The build quality seems pretty good. The only gripe I've noticed so far is the thread on the front of the dew shield that the cap screws into is a little bit rough. This makes it a bit difficult to screw the cap back on. I will attack it with a scraper sometime.
It was extremely well packaged and looks the part.
I will have to get a 2" photo adaptor as my current method of attachment for my camera is a custom threaded adaptor for the vixen threads. This scope does have a thread on the back but it isn't the same.
Also I've had no experience with the 2 speed craford focusser and will have to work out how to lock it for imaging. It has a couple of screws underneath it that seem to tighten it but not lock it like the one on my vixen rack and pinion focuser.
Did your Vixen come with the flip mirror? because your camera adapter will screw straight onto it if you unscrew one of the tubes
Quote:
Originally Posted by Terry B
The build quality seems pretty good. The only gripe I've noticed so far is the thread on the front of the dew shield that the cap screws into is a little bit rough. This makes it a bit difficult to screw the cap back on. I will attack it with a scraper sometime.
It was extremely well packaged and looks the part.
I will have to get a 2" photo adaptor as my current method of attachment for my camera is a custom threaded adaptor for the vixen threads. This scope does have a thread on the back but it isn't the same.
Also I've had no experience with the 2 speed craford focusser and will have to work out how to lock it for imaging. It has a couple of screws underneath it that seem to tighten it but not lock it like the one on my vixen rack and pinion focuser.
Did your Vixen come with the flip mirror? because your camera adapter will screw straight onto it if you unscrew one of the tubes
No.
My scope predates the flip mirrors. I have a slide mirror that I use with my little CCd but it has a SCT thread and this isn't the same thread as the new scope.
As a work around I have a T mount to 1 1/4" adapter that is usually on my guide camera. I can plug that into the back of the scope. This then leaves me with difficulty connecting the guider but I hobbled together an adapter that lets me achieve focus with the guider. It isn't very rigid but will do until I buy a proper adapter for the new scope.
As I'm at home this morning rather than at work (looking after my sick kids) I had a go at taking a pic through the scope.
The image is out the door of my observatory whilst it is lightly raining. The contrast is very low but at least it worked. I just aimed down into the trees and conveniently a couple of roos were down there.
The images are a full frame and a cropped section. I haven't processed them at all apart from a slight increase in contrast. The field seems pretty flat with little vignetting. I will have to do proper flats to check. There doesn't seem to be any false colour with the infocus areas but there is when it is out of focus.
As I'm at home this morning rather than at work (looking after my sick kids) I had a go at taking a pic through the scope.
The image is out the door of my observatory whilst it is lightly raining. The contrast is very low but at least it worked. I just aimed down into the trees and conveniently a couple of roos were down there.
The images are a full frame and a cropped section. I haven't processed them at all apart from a slight increase in contrast. The field seems pretty flat with little vignetting. I will have to do proper flats to check. There doesn't seem to be any false colour with the infocus areas but there is when it is out of focus.
Look great to me. Really cool to see those roos.
How do you find the mechanics of the focuser? Smooth?
looks very nice to me! what kind of range were they taken at? my guess judging by size of the roos in the pic/aperture+FL of the scope.. say 200 - 300M away?
The images are very sharp and seem completely free from any distortions.. which can only be seen as a good (read: GREAT) thing.
Coloring seems pretty sweet to, provided you focus it up as well as you have here on your first deep space imaging run I think the results will leave you with your mouth on the floor.
Good example subject too.. it really helps to see what these scopes can do when you have a subject that most people can scale in their minds. Seeing something thats 15m lightyears away is great and all that, but really, nobody can quite get their heads around the numbers involved to make an accurate judgment (or any kind of size comparison.)
Would be great to see a pic taken from the same spot of the same area with a dslr and a 35/50mm lens. (obviously you'd be very lucky to get the roos to pose the same for you)
I cant wait till your sky clears!! - Neither can you I imagine.
How do you find the mechanics of the focuser? Smooth?
Thanks
The focuser is very smooth. It seems not to slip but I haven't aimed it high in the sky yet.
Quote:
Originally Posted by AlexN
looks very nice to me! what kind of range were they taken at? my guess judging by size of the roos in the pic/aperture+FL of the scope.. say 200 - 300M away?
The images are very sharp and seem completely free from any distortions.. which can only be seen as a good (read: GREAT) thing.
Coloring seems pretty sweet to, provided you focus it up as well as you have here on your first deep space imaging run I think the results will leave you with your mouth on the floor.
Good example subject too.. it really helps to see what these scopes can do when you have a subject that most people can scale in their minds. Seeing something thats 15m lightyears away is great and all that, but really, nobody can quite get their heads around the numbers involved to make an accurate judgment (or any kind of size comparison.)
Would be great to see a pic taken from the same spot of the same area with a dslr and a 35/50mm lens. (obviously you'd be very lucky to get the roos to pose the same for you)
I cant wait till your sky clears!! - Neither can you I imagine.
The Roos were about 200m away.
If I used a 50mm lens from the same spot you woukd have just seen the dooway that I was aiming the scope through.
Because of the APS size sensor of the 40D, the scope equates to the equivalent of a 1500mm lens on a 35mm camera. Pretty good for wildlife shots. They were 1/60 sec exposures.
Quote:
Originally Posted by TrevorW
Terry glad to see my original post for this scope appears to have turned out well !!. Enjoy
The focuser is very smooth. It seems not to slip but I haven't aimed it high in the sky yet.
There are two screws on the focuser. The one closest to the eyepiece is for tensioning the focusser. The other closest to the scope/lens end is for locking the focuser so that the focusing wheels just turn freely. Need to balance the first screw for getting the tension right with a DSLR.
There are two screws on the focuser. The one closest to the eyepiece is for tensioning the focusser. The other closest to the scope/lens end is for locking the focuser so that the focusing wheels just turn freely. Need to balance the first screw for getting the tension right with a DSLR.
Thanks allan. I got my scope today.......and I was thinking about that two screws too.
Terry it would be great if you could image something bright and white during the day time. Would help to get an Idea of CA and compare to the AT Scope White post image posted in the CN forums.
For those who have this scope, I have 2 questions :
1) does your focuser able to rotate a little before you put on the finder?
2) How many screws did you see below your focuser?
For my scope, the focuser is able to rotate like 45 degrees if the finder is not installed. Once the finder is installed, the focuser is firm and tight.
Tthere are 2 screws below the focusser.
I haven't tried to turn the focusser without the finder and as mine is set up in my observatory I don't plan on removing the finder for a while.
well I had a go at the scope this evening, and it wasn't without its problems, mainly to do with the fact i haven't imaged in ages. I borrowed Alan Meehans mount in his observatory, and added a side by side bar, then mounted the 127APO. I still need to learn how to focus and as per usual i had software glitches. The mount also played up a bit. anyway I am more than impressed with the scope, the visual views through it are atreat, bands on Jupiter were so contrasty and clear - simply amazing, and the moon was crisp in the eyepiece. With these bright objects I did notice a purple halo in the Jupiter shot and a slight hint of colour (greenyyellow colour) on the moons rim, but i can easily look past that. the scope is brilliant. the focuser is stiff but workable (certainly no moonlight focuser). So here they are. Eta (out of focus slightly) a 30 second shot of Jupiter and a shot of the moon.
"I did notice a purple halo in the Jupiter shot and a slight hint of colour (greenyyellow colur) on the moons rim"
errr....isn't this supposed to be a triplet APO? But for the price, who can complain. Contrasty, clear, crisp & sharp images are the 'standard features' of any decent refractor We pay big bucks for good APO's mainly because we don't want that chromatic aberration
But anyway, I've given Gilman a list of 2-3 different scopes + the heavy-duty GOTO GPS mounts to buy just for testing out of curiosity. I'll sell them again soon after. So if anyone is interested to buy them after I'm finished with them, just let me know.
Colour may be caused by the eyepiece, many eyepieces show green/yellow on the Moon's rim when the rim is placed towards the edge of the FOV. The purple halo on Jupiter is a bit harder to explain though.
The best way to test for colour correction is to find a bright star and focus in and out and see how much colour there is in the in and out of focus images.
Here are a few images from my first attempt with this new scope last night. The nearly full moon really did not help with the swan shot but I did not want to use filters as the idea was to see how the scope perfomed - in particular wrt SA and CA. I imaged with the Canon 20D (unmodded) at prime focus.
Before I imaged I had a look at the moon, jupiter and Omega C with the supplied eyepieces (20mm and 10mm). The views were stunning (to me at least - I have never looked through a big refractor before). I found the focus crisp visually and the action smooth (I did have to take a little tension off). The cloud belts on jupiter were very evident at 20mm with 4 moons nicely frames, with more cloud detail showing at 10mm. I did not notice any false colour.
Then to the moon - very, very bright! I did notice a thin blue edge to the bright edge of the moon but it did not interfear with a tour of the terminator with really sharp views. I noticed the the colour fringe was more pronounced if the focus was off and varies in colout to green if my eyeline was off centre to the eyepiece. Once these issues were addressed I found that there was no noticeable false colour. Omega C resolved nicely in the 20mm ep with many pinpoint stars, I did not try my Vixen eps out to see if they gave better results as I was anxious to start imaging.
I connected the 20d and shot the moon at iso 400 and 1/1600s and then Antares and the Swan at iso 1600 and 180s. No flats were used but ICNR was on, I have only adjusted levels in PS.
I seems the scope is performing well but would benefit from a flattener - the outer 15% or so of the frame has some SA - I think the WO 0.8x mkIII flattener would be a good match?
Bottom line for the $$$ this is a wonderful scope.
