CraigT82

On 23/01/2023 at 11:49, wesdon1 said:

Hi all. I just ordered my first ever Apo! It's an Altair 66mm ED Doublet Apochromatic Refractor ( I know, some people say doublets aren't true Apo's? ) 

I paid £230 for it, second hand. I bought it to allow me to do wider field imaging, obviously better optics than my 3 Achromatic Refractors, and it should be more forgiving with the tracking accuracy when imaging. I have really struggle with polar alignment.   

Though I am getting better at polar alignment with every night of imaging I manage. 

Congrats! I just got my first apo too and I'm loving it so far, though only used it just the once for a quick session last night in fairly good seeing, but hope to get out again tonight as sky is currently clear.

1 hour ago, Stuart1971 said:

Why would the focuser take 50 mins to sag, and such a tiny amount..we are talking microns of sag here, over 50 mins of subs…if it was going to sag it would sag as soon as the weight was re distributed, after the slew to position and settle…wouldn’t it….

 

No as Adam says it can change as the scope moves, gravity is acting on everything in the focuser which is in a constant direction and so the effect would change as the rig moves around the sky. Normally seen to change most after meridian flip though so probably not what you’re suffering from.
 

Something seems to be moving over time though and as it’s a frac this is most likely to be something in the focuser… Cable drag maybe? 

Or could it be dew slowly forming on the objective from one side to the other (or top to bottom?) 

8 hours ago, RobertI said:

Great to hear about your first light and welcome to the club! Your experience quite similar to my first views - doubles and clusters amazing, planets awesome, faint fuzzies a bit "meh". But actually it's my main scope at present due to its convenience, and the lack of aperture hasn't stopped me seeking out those faint fuzzies anyway, and with its super contrast, its actually better on fuzzies than you would think, especially with narrowband filters. I got some binoviewers for planetary, lunar and solar and have been amazed by what extra you can see and how much more enjoyable the experience is. 

Yes I’d love to get it out to a really dark sky and see how it performs on the faint fuzzies, but to be honest I’ve never been a  fuzzyophile. I might see if I can find used UHC and O3 filters though as never tried them.

Binoviewers sound great and I’d love to use them but I only have sight in one eye so I have to make do with regular pirate viewing.

10 hours ago, Stuart1971 said:

No flexure, everything is rock solid…

Are you sure about this? Where was the scope pointing during this run? Rising or falling?  This looks like focuser sag to me, although quite severe for only 50 mins elapsed time .

Since bringing home my new-to-me Starfield 102mm F/7 ED refractor I’ve been frustrated in getting first light by either dad duties or just plain old cloud.

Tonight everything line up though and I managed a good 30 odd mins with the new frac and I must say this little pea shooter has really impressed me! Having been a died in the wool Newtonian fan for years I think this pretty little scope is swaying me away from shaving mirrors: Well for some visual work at least.

Started off with Jupiter as nice and easy to line up the finder. In goes my also new 4mm Nirvana and I’m treated to some lovely pin point Galilean moons and the equatorial belts with GRS immediately clear smack in the middle. Observing a little longer and I can start to make out a bit more detail to the north and south of the main bands but not a lot. I didn’t linger here as it was already quite low and with some clear atmospheric dispersion present. Had a real fright when I first looked through the Nirvana to see the most horrendous scatter before I realised that I was breathing on the eye lens when I looked through the finder 🙄. Slight adjustment to the finder rotation and and gentle dab of the lens with my wondercloth and away we go again.

Over to Betelgeuse to have a look at the stellar image, pop in the Baader 6mm ortho and Q 2.25 barlow for x268 and WOW! I’ve never seen so many diffraction rings! And with a perfect pin point airy disk cradled in the centre. Seeing pretty decent then. Beautiful twinkling orange colour too. Must admit I spent longer looking at this one star than I think I’ve ever done before. Totally forgot to look at the out of focus images diffraction patterns. 

Quick look at M42 with the 30mm Vixen NPL, transparency seems good but the view is bit disappointing… it’s nice but not 12” aperture nice. Not what I bought the frac for though so onwards and upwards (literally!)

With the NPL still in I take a quick tour up through the Hayades and onto the Pleiades. Lovely! The stars are perfectly set in their black velvet background, can almost believe I can see some nebulosity around Alcyone but I think it’s just moisture in the air, maybe the eye lens is fogging a little again. Just about fit the cluster in the FoV but would be nice to have a bit more context. *Off to FLO to look at big 2” EPs*. 

Time for the main event: Mars. In goes the 4mm Nirvana for x178 and almost immediately - well…  after figuring out how to actually look through the EP with it so close to the ground, *cue the addition of a pillar extension to my FLO trolley* - I’m met with large dark albedo features covering most of the lower half (Southern Hemisphere? No idea what the image orientation is with this thing!), and with a little more observing smaller dark markings at the 10 o’clock position in the upper half. Also present is some whitish brightening at the top (Cloud? Checking an online Mars map I believe the lower half dark features were the Aurora Sinus region, and the upper one was the Lacus Indus region). I just let the planet drift through the field and it is impressively sharp all the way to the edges. Nice eyepiece this. 

Crank it up a notch with the 6mm BCO and Q barlow and the detail is all still there but larger and still sharp with a very well defined limb, not mushy at all. Spend about 10 mins nudging and observing quietly and just start thinking about putting the 4mm in the barlow for x400 but I start to see the tell tale signs of the objective dewing up and I decide to head back indoors instead to let the scope dry off. 

Well I must say I thoroughly enjoyed that session and of the few refractors I’ve had before, this is the first one that I’ve looked through and come away from happy and satisfied. There’s no way I’m going to drag the 300p and AZ-EQ6 out for a 30 min session - which with my other commitments that’s mostly all the time I get nowadays - so this little frac is going to step in a fill that void perfectly and drag me back to visual observing that I’ve missed out on for a couple of years whilst I focused on imaging. Very happy chap right here  

Exciting times Magnus 😁. What focuser option did you go for? Do you plan on using it side by side with one of the newts on the AZEQ6? Suppose that might be a bit awkward with one ep at the back and one at the front!

I must say that whacking your name on the AP waiting list as soon as you get into the hobby is rather a bold move 😂

Sounds like the PA is way off? 

Suck. Draws an undisturbed flow of air down the tube which washes over the face of the primary removing the boundary layer, also sucks the micro boundary layer off the secondary.

Fan isn’t for cooling the mirror in my opinion, more for managing the air in the tube - trying to avoid temperature deltas.

Yeah as above… if you live in the city with very light polluted skies I’d go mono with barrow band filters. You could just start off with Ha to begin with then add filter wheel and other bands as you go 

30 minutes ago, Acrab67 said:

 

Yes, but it cannot avoid the deflection caused by the tightening of the HG adapter by the focuser itself

It does, the OD of the parallizer has a specific shape (not round) that ensures parallelism between accessory and focuser drawtube.

IIRC the instructions say that the thumbscrew of the focuser should be located opposite to the thumbscrew of the paralliser for it to work optimally.

4 hours ago, Acrab67 said:

Well yes, the Glatter Parallizer partly solves the problem from the point of view of the placement of the Cheshire, but there is still the deviation caused by tightening the adapter in the focuser. By the way, I don't understand why a Cheshire hasn't been made directly in 2"

The whole point of the HG parallizer is to ensure that the accessory is parallel with the focuser drawtube. 

No, not without an adaptor.

The skytee has a M10 bolt connection which is a little bigger than the 3/8” on that smaller tripod and extension.

16 minutes ago, TrojanMan said:

As for pictures this would be the ultimate goal:
https://en.wikipedia.org/wiki/Andromeda_Galaxy#/media/File:Andromeda_Galaxy_560mm_FL.jpg
I have no doubt this will take a massive learning curve and much trial and error and new equipment to achieve this goal. If the listed eq above can do even a fraction of that I would be happy

That image is like a punch in the face! There’s a lot wrong with it but I understand how it appeals to someone new to the astrophotography game.

You could great images of M31 quite easily as it’s a big and relatively bright object and it doesn’t take much in the way of expensive equipment to do. 

The shopping list you’ve put together is a good place to start, you wouldn’t get much use out of the 7nm Ha filter with the 533mc though, it’s meant to be used with monochrome cameras. With a colour camera you could make use of one of the various dual band filters like this , more expensive but more useful with a colour camera (and there are cheaper brands out there too)

https://www.firstlightoptics.com/light-pollution-reduction/idas-nbz-dual-band.html

Things you haven’t listed are:

-Power (battery or mains?)

-UV/IR cut filter

-laptop or tablet to control ASAIR

-software for calibration, stacking, processing

-dew straps and controller

17 minutes ago, bosun21 said:

A pair of Astro gloves courtesy of @Littleguy80. Just in time for tonights first light in these freezing conditions. Perfectly leaving your 3 essential fingers open to change eyepieces or whatever.

Oooh I need me some of these!

14 hours ago, TrojanMan said:

Just want to take great pics of DSOs.

You could post up some great DSO images you've seen (with credit) and we could guide you in the sort of kit you'd need to produce the same kind of image?

Beautiful... a real masterpiece

Courtesy of the gentleman @bosun21 an absolutely pristine Starfield 102ed

Great build quality and stunningly sharp views looking at the branches across the way against the blue sky. I swear I saw an ant wink at me 😉. Love that the baffles continue down the focuser drawtube. I’m finding the twist-lock ring on the end of the drawtube very stiff though, I keep unscrewing the adapter when trying to undo the twist lock. 

On 06/01/2023 at 15:32, Stu said:

A 6mm and 10mm BCO for me. Mainly wanted the 10mm to try out as a Bino pair with one I have already.

Simple, no nonsense and great value EPs. Love mine. Tested the 6mm back to back against the 6.5mm Morpheus in the moon and found it to be sharper and with better contrast. 

Star suppression is absolutely fine in my view. You’re simply mitigating a limitation of your data acquisition system, in the same way that noise reduction, sharpening, applying flats and darks etc is.

Here is a grossly overstretched image of Mars (I was trying to capture Phobos  and Deimos) which shows the fat spikes well. The planet itself was the same width in the image as the spikes.

In normal planetary imaging we don’t really stretch the data so the spikes don’t show up in normal exposure times (few milliseconds).

Really nice work 👍🏼

Awesome Geof! The blending is excellent, well done on capturing such consistent images from the uk!

Dew will form on any surface that is colder than the dew point temp, usually this will be on  any surface exposed to the sky. The dew shield shades the objective from the sky and so dew is delayed from forming here by slowing the rate that the objective cools. 
 

Never used dew heaters so can’t answer you queries about those sorry! 

That’s an absolute cracker Francis…. Top drawer stuff! 

Not sure that wil work too well as the description states it’s for uPVC and wood, and soft metals only.

Ive used this stuff before which works well for sticking mirrors in (also gluing secondaries too) 

V-Tech VT-130 Clear RTV Sealant Adhesive Quality Flexible Silicone: 75gm Gasket https://amzn.eu/d/7Sh7qS1