Ian McCallum

On 10/08/2021 at 15:52, Xilman said:

Undoubtedly unfortunate.

However, it might be of negligible effect when using it. It might be worth trying it out before seeing if you can ask for a refund.

At least one professional telescope, the 2.7m at McDonald Observatory, is still in constant use despite the primary being shot seven times with a 9mm handgun at point blank range and then hit  several times with a hammer. The craters so formed produce a roughly 1% drop in light gathering and a minor amount of diffraction artifacts.

I did try 320x magnification on Almach, last night. That was using the Sky-Watcher Evostar 120 and BST StarGuider ED 3.2mm eyepiece. To be honest, it was too much for the seeing conditions and scope. 

For me it's my second hand 28mm 2" LET, great for wide views. 

Second would be my BST StarGuider 12mm ED, for closer in observing. 

Lastly would have to be the BST StarGuider ED 8mm for occasions when the seeing is good. 

Some photos and videos of the sun through a solar filter, just a few hours ago.  There's at least one sunspot visible.

Sky-Watcher Evostar 120 achromatic refractor and Meade 4000 Super Plossl 15mm eyepiece, plus mobile phone holder.

These were taken with a smartphone holder attached to the eyepiece. 

Another wee muck about with the Sky-Watcher Evostar 120 achromatic refractor and the moon, this evening. I was using a Meade Super Plossl 15mm eyepiece. 

I actually saw Orion for the first time in ages. Betelguese looked not too bad, as was Rigel. I could even make out the Orion Nebula and 3 of the Trapezium stars too.

On 29/09/2021 at 14:14, Louis D said:

For low power views they would probably be fine.  You could always add a Baader Contrast Booster to suppress all purple and deep blue light if the color fringing bothers you.

At high powers, their chromatic and spherical aberrations would detract from the view.  It really depends on what you want out of a refractor.

Whilst I was forewarned about CA with achromats, I picked up a used SW Evostar 120 recently.  I can easily detect the purple fringing and it's more obvious than I thought it was going to be.  I guess having used a 8" Dob for over 18 months has spoiled me...🙄

On 28/09/2021 at 06:40, dweller25 said:

if the 8” Dob in your avatar is yours then you will have to spend a lot of money on a refractor to beat it’s visual performance on both deep sky objects and the planets.

I picked up a used Sky-Watcher  Evostar 120 Achro recently, you're observation (no pun intended) is absolutely spot on.

Firstly, Jupiter with the Sky-Watcher Evostar120 Achro - using the whole BST StarGuider range 25mm-3.2mm.  CA was apparent right through-out the who range of magnifications.  There was a bit of a breeze this evening, which didn't help seeing.  I decided to move onto Almach, which I discovered by accident recently.  I used the whole range of the BST eyepieces again, but couldn't obtain a totally clear image, as seeing wasn't great.  CA was present on the images I was viewing, having being previously spoilt by a 8" Dobsonian.

2 minutes ago, John said:

Filters won't correct CA but they can filter some of it out so it does not reach the eye.

 

 

Yep, filters don't add light, just subtract from it.

I was looking at the colour wheel and trying to work out what was the closest opposite colour to cancel out the purple fringing.  The closest I could see was Wratten #102.  Sorry that the image for the Wratten #102 being so small, but I felt the correct colour was somewhere between yellow and green.

Just curious if anyone has tried Wratten filters for CA correction in achromats?  I was thinking a Wratten 11 or 102 might be good to reduce the purple fringing.🤔

Some WD40 or similar to break down the foam adhesive, followed by Meths or IPA to remove any oily residue left by the WD40.

That's interesting to know, regarding LP and the size of the finder scope. I've only got the 9x50 variety.

I managed to pick up a used one from a SGL member, thanks. 👍

This awful weather is putting me off getting more equipment.😒

I'm not in a desperate hurry for one at the moment, so will hold off and see what comes along. Bad time of year, etc. 

1 hour ago, Mr Spock said:

Looks accurate at the moment. Cloud, cloud and more cloud 

Next Monday and Tuesday look promising though.

Must be because I got some more astronomy related stuff, recently.🙄

So basically the EQ5 would be good enough for the ScopeTech STL-80A 80mm f15 Maxi then?🤔

14 minutes ago, Mr Spock said:

I'd advise leaving it. As long as it's not too dirty it won't affect image quality.

Yeah, that's what my gut feelings were too.

What's the advice regards dust inside the lens elements of a refractor? 🤔

I cleaned the objective lens with Baader Wonder Fluid and the Baader microfibre cloth.  I used the method described below... 

https://www.skyatnightmagazine.com/advice/clean-a-refractor/

If the dust inside won't affect the image, my thoughts are to leave well alone.

I just call it 'Fred'.🤣🥼🚪

7 minutes ago, Alien 13 said:

Never had a problem with the bolts myself provided you dont try tightening one without first loosening the other and they only need to be finger tight..

Alan

This guy did a good job of replacing them, on a second hand mount that he bought.  I wonder if he's a member on here?🤔

https://youtu.be/tGTY61b5HPg

2 minutes ago, Alien 13 said:

The EQ5 is a good mount for visual use provided its not overloaded if an Equatorial platform is what you want, the addition of even the single axis motor will keep most objects in the FOV for many minutes providing stress free viewing.

I mentioned visual use but it can track well enough for Lunar or Planetary imaging which is often done by short bursts of video or very wide field AP with a DSLR and say a 50mm lens but anything else starts to make things more difficult though not impossible.

Alan

Any video or photos will just be occasionally, the vast majority of stuff will be visual.

2 minutes ago, Stu1smartcookie said:

Firstly , congrats on the scope and the potential mount purchase , Ian . 

An EQ5 is a great mount that will easily cope with the 120 . Where people have cause for concern is when attempting serious  astrophotography with the mount  . Most people recommend an HEQ5 . 

But for visual the mount is sound and is rightfully reknowned as a classic. 

I think the payload maximum  for visual is listed around 9kgs . 

Any Cons ?... maybe you can update the altitude bolts as they tend to want to bend , also i believe the mount comes with very short slow motion controls rather than the long cables . 

Stu 

I plan in the future to get one of the Scopetech 80mm F15 refractors from Autie @FLO, so that will be the longer OTA to go on the EQ5.  No problems regarding the bolts, as I've already been forewarned in a YouTube video. I think one set is M8 and the other is M10, so no major problems.

I'm close to pulling the trigger on buying a SW EQ5 Deluxe mount and tripod, for my recently purchased 2nd hand SW Evostar 120. 

My thinking is that this mount should easily cope with with telescope, with no problems. I'm hoping it's somewhat futureproof for most things I'll ever use on it. 

I really like to do my research on a potential new purchase, so that I don't end up with the proverbial 'white elephant'. 

Those who have this or previously used it, what's the quirks, idiosyncrasies, pros and cons of this mount, please? 🤔