what to do when it is cloudy again

[happy-kat]

Take apart a brand new scope! and fettle it.

Many thanks to the Astronomy Shed for the video on this so had a go.

New scope thread is here.

So it was take it apart as I wanted to just do the lens and tube mod.

I was happy with the focuser feel so decided I didn't need to do that and with no laser I could not check colimation so also meant not to bother removing the focuser end.

So lenses out.

Then with a permanent pen blackened the edges carefully, did not want to slip!

Not onto the tube, this had the odd bare or thin patch of black paint and also quite a few shinny bits with nuts, threads and edges, so out with a brush and some matt black water based paint I had sort of like a hard block of poster paint, and onto several layers of blackening.

Afterwards with flash.

And with no extra light showing as black and black.

Waiting for it all to be fully dry and then onto assembly...

[Daniel-K]

does that not affect the collimation when you put i back together?

[happy-kat]

The lenses can only go in and sit in one place and I did not remove the focuser unit which is the only thing available to tweak colimation as there is no real colimation on this short tube refractor only option is by miss aligning the focuser tube ever so slightly if it were needed from reading.

[happy-kat]

The scope re assembled with out issue and a little jiggle helped the lenses re seat.

Hopefully all will be OK when I get to test it.

[happy-kat]

I guess in the factory the lenses are placed together and placed in the tube and all assembled I hope it's as simple as that as I done it now :-)

[Myopicus]

"A little jiggle" 

Love that - is it a technical term?   

[happy-kat]

It is now ;-) may have heard it used on the video I watched on doing these mods. Checked the seating again last night, loosened off the bezel then a little jiggle then finger tightened up.

[happy-kat]

Tomorrow is clear forecasted so hopefully get to test I didn't muck it up.

[happy-kat]

The good news is that it appears to be working fine still and is no worse for the experience. But me being me I might check it all again lol. I think I saw less CA on Jupiter too. Placebo who knows...

[Alien 13]

Im sure the effect is real i have considered doing this to my scope i dont think its only newts that benifit.

Alan

[happy-kat]

I should add an update to this seeing as I finally got to use it on a tripod. As this was all about minimising CA.

On Jupiter with 32mm there was no CA nor was there any with my 16mm that I recall as I type this. I then put in the WO 6mm and there was just a small amount which was often just a hint to also being none at all. Whether this very little CA is down to my modifications I wont know as I was umable to do a before on Jupiter as no tripod but the results I saw today I am more than happy with.

Moon next for a test I guess.

[Mr TamiyaCowboy]

not done nothing to my ST80 yet. 

can say jupiter had CA last night through mine, very noticeable purp/blue.

on a none modded tube and lens unit. but at 10mm and no barlow you could make out jupiter and four moons. 

Mars at 25mm was fine, just the usual orange star like thing in the sky.

Mars using the standard 10mm skywatcher eyepiece and a 2x cheapy barlow.

not a good sight at all, impossible to focus down enough without CA coming in strong

i did notice a marked drop in  brightness, the barlow and 10mm seemed to

act like an extra -4 stops ( F number (apeture F)

[happy-kat]

The astronomy shed video on you tube is what I followed. I did these changes to the Mercury 705 today so will be interesting to see if that has improved the CA on that tube.

I saw a lovely view of Jupiter in the 80 last night no Barlow used with the 16 and 6 mm that I have. Clear mid bands and darkening at both poles the best view I have had including my heritage at nearly double the apperature.

[happy-kat]

I hope one day to collect some flocking off cuts so I can do the internals properly though the paint I have used does appear to be very unreflective.

[Mr TamiyaCowboy]

Gah you Happy-Kat 

now been hunting high and low for a perma marker. 

draws cupboards in the sink under the sink, in the pen pot.

i found one, got everything ready and, ITS RED !!! a red marker lol !!!

if you get to glance tonight pop back and update, be nice to see if it has worked some wonders.

flocking is on my list to , have studied the ST80 mod video lots of times lol. 

Would love to be able to shoehorn a Dual speed focuser to the 80mm i dont like focus hunting

like i had to last night on mars.

Are you getting stars stretching on the outer field of view ? 

last night i noticed this a lot when trying to see jupiter, bad stretching of star field 

on outer edge, but nicer to the center of image ? 

If so did the blacking of lens edge also help with this stretching ?

[happy-kat]

Red, how frustrating.

We don't have exactly the same scope but I rekon they are made side by side in the same factory as the same unit.

I can't say I notice obvious stretching of stars at the edges so will have a particular look next time it is clear as there has been rain and hail and sun today!

I could not check how aligned my focuser assemably was because we don't have a laser light and I could not get a fashioned alternative with a bright LED to be any use which is why I did not do any of the focuser mods I decided leave well alone unless I had the ability to guage the accuracy of putting it back together.

If it is clear later I will use the stock 10mm in case that shows more CA.

[happy-kat]

Took this 80 out again just now, yesterday the viewing was awsome and clear today rather murky and interestingly I had slightly more CA today it felt very cold and wet the air.

I can report that the stock 10mm showed the most CA of my eyepeices used from 32 - 6mm.

I observed that as I moved my eye around it could look worse or disappear, anyway it is not as bad as I had thought it would be when I first got the scope (it is pretty strong in the other scope yet to be retested).

You asked about star stretching.

The views at the very edges are not as contrasty but I did not feel I really noticing star stretching, I had a really good look and they were not seagull shaped or longer looking just not as crisp as in the middle.

[Mr TamiyaCowboy]

Lovely Kat and thank you. 

so the blacking does help then, last night 10mm on jupiter was CA all the way.

25mm on barlow an ugly sight, so i went star hopping.

02:35, my eyes hurting i set the scope back up, lobbed it at saturn, shoved in TWO of those

cheap SW 2x barlows and the 90 diag , 25mm in the line to. 

OMG i split saturn from a CA ugly blob to a small but perfect ( with little green and blue banding) saturn and even split

the ring from the main planet body. 

i didnt have an 4x barlow so i went with the dual cheapy risky but paid off.

[happy-kat]

In my Heritage at x65 I can split the ring from the planet so you may not need all that grunt to do that, hopefully soon I will get to try to see what I can see as I do not have the same magnification power levels available as you.

Perhqps try to get hold of some flocking material and if you are going to open up your scope may as well get the benefit from flocking as well and I read on one post a user felt flocking the focuser tube had greatest impact though that sound very fiddly. When I do mine I intend to flock a roll of card and drop that into the tube top.

[happy-kat]

I have posted my findings so far on doing the same to the Mercury 705 here

[happy-kat]

Have updated my Mercury 705 post, link above.