Biggest thing you can fit on a virtuoso mount?

[Mr niall]

Hello there - I seem to have acquired a second hand virtuoso mount.

but... I’m wondering what the biggest thing I can safely put on it is? I keep hearing rumours about Skymax 127s and Heritage 130p’s fitting on them but in the same stroke hear things like “horribly unbalanced” or “won’t work at the zenith because of overhang”  and I’m all confused now!

im pretty confident that a 102 Mak will fit on there but I think.... the finder will be all upside down and round the corner as I’ve heard they do two different types of tube depending on the mounting but the OTA you can buy on it’s  own would have the finder but n the wrong wrong place. I really really don’t fancy drilling another tube to fit a finder bracket. (Last time I did that was very tense and stressful!)

many thanks all!

[happy-kat]

I thought a member who has very similar equipment to me also has the 127mm mak. When the name clicks I'll add it here as I'm sure he's tested both on the virtuoso.

[happy-kat]

@Geoff Lister I think you have both the virtuoso and 127mm mak maybe you could help answer this post?

[Geoff Lister]

11 hours ago, happy-kat said:

Geoff Lister I think you have both the virtuoso and 127mm mak maybe you could help answer this post?

The Virtuoso mount will take both the 127mm Mak., and the Heritage 130P's truss-tube Newt. I have tried, and used the mount with both. However, as both are longer than the 90mm Mak., if they are mounted so that they are balanced in the dovetail clamp, the Mak's diagonal/Newt's rear plate will foul the azimuth axis clutch adjustment knob at high altitude angles.

There is a solution to view high altitude objects without putting too much strain on the mount. It is possible to move both forwards (effectively upwards)in the dovetail clamp, to clear the rear obstruction. With power still ON, the mount will still keep tracking alignment as you make adjustments in the dovetail clamp and the altitude clutch.

The other consideration is the overall mass and moment-arm of the larger OTAs. The Virtuoso mount has a much higher maximum slew rate than the Skymax's tripod mount. This is not a problem with the light, short, 90mm, (1.3kg, I believe) but the 127mm OTA with finder and eyepiece is about 3.5kg. The Virtuoso mount's slew speed starts at maximum (level 5) by default, but can be reduced by pressing buttons "4" or lower. With the heavier OTAs, even when balanced, I do not go faster than "4". In most cases, this is not a serious restriction, as you can release the clutches (holding the, possibly, unbalanced OTA), point in the rough direction of the desired object, tighten clutches, and then use the buttons, at lower speeds, for final alignment.

I would not fancy dismantling a Mak., drilling holes in the bare tube, and then re-assembling and re-collimating. If the finder is in the wrong position, it may be possible to mount the OTA facing south, and do a southern hemisphere mount calibration. I believe that this keeps the tracking's azimuth component, but reverses the altitude component.

Geoff

[happy-kat]

That's great.

I think I'd get a cheap red dot finder with a flat base (astroboot) and just stick it to the tube with a sticky pad in the place it would need to be.

[Mr niall]

Thanks both

[Alfian]

23 hours ago, happy-kat said:

That's great.

I think I'd get a cheap red dot finder with a flat base (astroboot) and just stick it to the tube with a sticky pad in the place it would need to be.

A Rigel QF would work too. More expensive but a better finder.