Posts Made By: Phil Barker

I'll start and say no

I don't doubt you re ganymede I've previously seen an L shaped feature just in the south eastern corner of its disc.

I was using a 14.3 inch cassegrain and it was 1996 also detected it just in my old celestron 8 which was a good planetary scope.

I needed high power 333 and 430 to see it well in the celestron.

I found with the parabolising ussing a full tool with mirror on top can lead to an uneven surface in short order if contact is'nt good. Pyrex takes a lot longer to get the same effect probually 2-3 times more work for the same ammount of glass removed.

Ended up using a small starlap (tool on top)with a full tool and 1/3rd (mirror on top) wets to get there.

Very slow polishing with a wetter mixture cured the dog biscuit which i also encountered.

Used the scope last night in reasonable conditions and she went well superb on 47 Tuk and Omega Centaurus even at high power in average seeing. Impressed everyone present. You guys must be amazed when you see these globs for the first time.

I owned both a very good celestron 8 and a delux mk67 with .989 strehl ratio.

The celestron I thought was a killer on planets very sharpoptics startested to close on 1/8th wave. Slightly undercorrected but nice images.

The MK67 was at first disapointing me but when I collimated it and waited for the optics to cool it was something else.

Inky black bacground perfectly even diffraction rings compared to more indistinct diffraction patterns on the C-8 and greyish background.

I wound the intes up to 500 one night and was amazed on the moon the image was still nice. the obstruction was 53mm out of 152mm just under 35% the C-8 was 34%.

I feel one major advantage is the better corrector coatings on the intes v the celestron. Also baffling was clearly more effective.

Re the Mak mk67 it can't be denied it had the edge for planets and I was skeptical beforehand. On deep sky the C-8 was brighter and the extra resolution came to the fore especially on globulars.

So there you go the mak cass inch for inch was superb on planets. In saying this compared to a refractor the obstruction meant fatter stars ie more diffraction rings even with superb optics.

the focusing is tolerable from what I've seen. Get a fan to cool the scope.

the biggest disapointment with my mk67 was cooldown I would probually still have it if the cooldown was quicker.

I can help here it will at a pinch ie the mount is rated to 20 pound but the mn66 would be near the upper limit at 15 pound. I would recommend a lightweight finder.

While I save my pennies for a g-8 mount I will be putting a mk715 on the same mount until i can afford the G-8.

The skyview is shown in sky and tel with a 6 inch f-8 newt which weighs 15 pound the same as the mn66.

The skyview is an improved version of the older G-5

From mine i see better smoother gears and motors and a better tubular tripod than the last g-5 I owned some years ago.

It was a good mount for my mk67 i had at the time.

I see in sky and tel the periodic srror is a respectable 25 arc seconds mine is similar quite smooth overall I am satisfied but it will be taxed with the 15 plus pound mk715 ota.

A G-8 would be much stronger but 4 times the price.

The APM 102 would want to be much better than the bw optic triplet to be even in the ballpark.

A friend owned 2 sent the first back when it startested to 1/2 wave the replacement was 1/4 wave but nothing to write home about colour correctio wise.

Reading the review I have my doubts and suspect its a rework of the same binocular objective which the BW optik had apparently.

I hope someone compares them soon.

good luck getting it off. it makes it virtually impossible to coat again and I would not advise using this with a secondary.

Why well outgassing in the vacum chamber and silicon is difficult to completly remove.

Good effort

I just finished a 6 inch f-6 for a friend and tested it last night.

Optics went well an excellant startest and supern alround performance.

I used sonutube and a square base Similar system for the side bearings. I cut some PVC(160mm and glued formica on them.

Did you do the mirror and is it f-9?

Good effort

I just finished a 6 inch f-6 for a friend and tested it last night.

Optics went well an excellant startest and supern alround performance.

I used sonutube and a square base Similar system for the side bearings. I cut some PVC(160mm and glued formica on them.

Did you do the mirror and is it f-9?