GTom

17 hours ago, Adam J said:

There is not as much difference as you might think as the 127mm does not have a 127mm clear aperture only 118mm. No idea how SW get away with that. Honestly the 102 cools faster and is more portable as it will go in hold luggage easier. The 118mm will outperform it just don't expect the margin you would get if it was a true 5 inch scope. 

If the 127mm "is only 118mm" then the 102 isn't "102" either. Even 40% (will be more in reality)  more light will give a visible difference.

The FL difference is marginal, APERTURE gives you resolution and light gathering. Indeed, that 5" Mak will be brilliant on planets, even Uranus is possible.

ADC's are not without fault, diminishing returns @higher altitudes could be negated by optical imperfections of the ADC unit and collimation difficulties. ADC will not improve seeing either.

Still, it may very well save the day for us in the UK (clouds allowing...) and other countries at similar latitudes, I am in the process of choosing one.

Any update on these two?

My planned imaging train: lx200 10", Powermate 2x, ADC, Filter wheel, Altair 174m camera.

Anyone?

Seems only zwo specifies surface quality and publishes a transmission curve.

Altair just joins the possible candidates

Just found an ADC on our sponsor's website with a very attractive price tag from StellaLyra. Anyone could comment on its quality and usefulness? I intend to use it with a Meade f10 SCT for both visual and photo.

Just found an ADC on our sponsor's website with a very attractive price tag from StellaLyra. Anyone could comment on its quality and usefulness? I intend to use it with a Meade f10 SCT for both visual and photo.

Summary:

K9 glass
Anti-reflection treatment with a reflection of less than 0.3% and a range from 350nm to 700nm
Inclination of the prisms 2.5°
Total length 106mm
Free aperture 27.2mm

Looks great! Have you used a reducer/corrector?

Industrial IPA is likely good, would get a cleaner water though 😄

I was wondering if distilled water could be cleaner-better than de-ionised. Automotive suppliers nearby only stock de-ionised as it is perfectly fine for all kind of motoring use. Distilled from amazon/ebay is a bit more expensive (won't break the bank though at £2/L) but might be better...

Never added detergents before, guessing a fragrance, etc. free type is needed for telescope cleaning.

I am in the process of cleaning my recently acquired LX200 SCT. As mold just started to set foot, I had to act quickly, had a rough cleaning with isopropanol de-ionised water 1:1 mix followed by pure isopropanol. This worked so far with camera sensors and less-dirty mirrors. This one seems to be dirtier than usual, quite a bit of sludge remained.

As already wasted about 1/2L of precious isopropanol, I wonder what could be a more economical cleaning solution? Also, any recommendations for the water part, where to get larger quantities of pure distilled water? Can I add some detergents to get rid of less soluble-more stubborn contaminants that prefer just changing pattern instead of leaving the corrector plate😄?

Took my 10" LX200 GPS apart last night (decent cleaning is still to do): no counterweight

2 hours ago, John said:

The meade newtonians and their 7 inch mak-cassegrain certainly have large metal weights behind the their primary mirrors.

Often an early modification of such scopes is to remove the counterweight. I understand that it is thought that the weight slows down the cool down process by adding mass close to the primary mirror.

 

Having a heavy camera it would be a great idea to remove any weight from the primary side. Will have a look on my copy, being a wee bit scared to disassemble the entire OTA though 😀

Right, just picked up a 10" lx200: it came with stock mirror lock

Mind you it is an Achromat, for that f8 is a bit fast. The f15 would be great for planetary.

No problem unless it's a 25x150 comet hunter that might be bigger and heavier than your maximum carry-on size. My trusted 10x50 often comes with me.

The best is to try finding a drawing on the dovetail candidates and check which one offers the hole spacing you got. Wirst case buy one with no/very few holes and drill at your convenience, Aluminum is easy to drill and you won't destroy anything.

I recently bought a 355mm one for my TS 90/600:

You'll need something in the 400mm+ range.

Tip: even if you don't plan to import ftom Germany (I didn't either), the TS Optics site is very good for measurements:

https://www.teleskop-express.de/shop/index.php/cat/c308_Dovetail-Bars.html

ThousandS not, a good £7-800 can get you started with AP if you don't mind 2nd hand equipment and a bit of DIY:

get a decent f4 150mm Newtonian on an EQ5, tune the mount. Get a used canon dslr from ebay <£200, dig out its uvir filer, add a coma corrector (any half-decent £100 second hand unit would do for starters), clip L-type filter, leisure battery, a cheap guider and you are ready to go.

True, AP is more hassle, I do enjoy visual better. AP simply shows different things.

On 29/07/2023 at 16:46, John said:

It seems to be around magnitude 12.5 or 12.6 visually, according to this (latest record is at the bottom of the list):

Supernova 2023ixf in M101 (rochesterastronomy.org)

That seems to tally with the last time I observed it which was a few days ago now. 

Fantastic, might be a visual item in my 10" Meade scope! We are just getting our nights back next week, clouds allowing I'll check it out.

You need those early 1900's skies and L-frames.

LiFePO4 12.8V/30-40Ah should cover you fine even with a power-hungry low-temp ccd and heavy mount.

Investing I had already, carrying it is another question. The eq3-2 is super light, weighed 4kg's the other day. My g11 weighs about 3x that: still perfectly transportable by car but definitely no flight luggage issue.

Got some very interesting tuning advice here, will definitely try this cheap fine tuning before moving on: 

It's a 10 years old mount, no link sorry. I am 500 miles from it ATM, can't post pics either I am afraid. Both axes are stock motorized and I recently updated the firmware (03.39.10, from here: http://skywatcher.com/download/software/synscan-v3-hand-controller-firmware/)

5 hours ago, vlaiv said:

You need complex optical system to produce lateral chromatic aberration - like telescope + eyepiece (especially wide AFOV eyepieces exhibit this) or camera lens with multiple elements (7+) which correct other aberrations but introduce this one.

I am afraid a doublet-triplet apo + reducer setup may already qualify for that "complex system" title. Can't recall which scope but I do remember seeing LA-CA on apo+reducer system (radial pattern, blue out red "in").