Another Q...can someone explain the different sizes of EQ mounts, googling has got me no where

[digital_davem]

I'm looking for something that will provide a solid dependable mount for my classic 3" refractor with its 41/2 foot long tube. Eq1, Eq2, Eqn what does it all mean in reality?

Cheers

Dave

[Davey-T]

Do you need an EQ mount ?

Dave

[philj]

Its all down to sizes and load capacity, EQ1 (equatorial 1) is small and handles small scopes, dont know the capacity). Then they go up gradually.

For a 3" (sounds f15), I recommend a minimum of eq3/2 with good tripod, not the nasty ali/plastic early jobbies. However an eq4/5 would be very stable. I ve used my 3" f15 on heq5 and its rock solid

[Roy Challen]

I have the same scope and it sits on a Skytee 2- on the original Prinz wooden tripod ( albeit modified and strengthened) and fitted with the superb Prinz slow motion controls. This is a heavy duty alt-az mount that easily copes with all 3 of my scopes simultaneously. I have forgotten what vibrations at high magnification are.

The EQ3-2 is a lightweight mount really. It could handle the weight of the Prinz, but not the length. It wasn't really happy with a Tal RS on it either. If you must have an EQ mount, make it an EQ5 at the least.

[pipnina]

Its all down to sizes and load capacity, EQ1 (equatorial 1) is small and handles small scopes, dont know the capacity). Then they go up gradually.

For a 3" (sounds f15), I recommend a minimum of eq3/2 with good tripod, not the nasty ali/plastic early jobbies. However an eq4/5 would be very stable. I ve used my 3" f15 on heq5 and its rock solid

I don't like the EQ2. The dec slow-mo runs out of turn after a while, the dec is sticky when moving without slow-mo and it's a pain in multiple places to move around. (wherever the pointy bits dig in, it also weighs more than twice as much as my scope).

It's usable... But far from comfortable.

[RichM63]

The simple answer, is that the higher the EQ number, the bigger, more solid, higher capacity, and of course higher price the mount.

Rich

[digital_davem]

Do you need an EQ mount ?

Dave

Good question!  I don't know. In my 1976 edition of the Observers book of Astronomy, Patrick Moore says I do...

[digital_davem]

Its all down to sizes and load capacity, EQ1 (equatorial 1) is small and handles small scopes, dont know the capacity). Then they go up gradually.

For a 3" (sounds f15), I recommend a minimum of eq3/2 with good tripod, not the nasty ali/plastic early jobbies. However an eq4/5 would be very stable. I ve used my 3" f15 on heq5 and its rock solid

The scope is a 1250mm f16.5

[digital_davem]

The simple answer, is that the higher the EQ number, the bigger, more solid, higher capacity, and of course higher price the mount.

Rich

I kind of figured it would be something like this - what's missing is the detail. Are these EQ numbers some kind of standard like shoe sizes, car wheel sizes, paper sizes or are they some kind of loose-can-mean-anything description?  I would have expected that with a scientific discipline like astronomy there would be standards and you would simply measure and weigh the scope and there would be a chart somewhere that told you what size mount you needed. I'm beginning to suspect it ain't so...

[John]

The numerical mount types seem to have been used by Skywatcher principally although Celestron and Meade have also used numbers for some of their models, confusingly bearing little or no relationship with the Skywatcher series !.

Having recently been at a few outreach events and helped newcomers to the hobby who were finding equatorial mounts pretty frustrating I'd suggest that an alt-azimuth mount is at least worth considering.

Your long 3" refractor will need a pillar extension to keep the eyepiece at a reasonable height but the Skywatcher AZ-4 alt-azimuth mount (another number !) on a stout steel tubed tripod would probably do the trick.

[digital_davem]

I have the same scope and it sits on a Skytee 2- on the original Prinz wooden tripod ( albeit modified and strengthened) and fitted with the superb Prinz slow motion controls. This is a heavy duty alt-az mount that easily copes with all 3 of my scopes simultaneously. I have forgotten what vibrations at high magnification are.

The EQ3-2 is a lightweight mount really. It could handle the weight of the Prinz, but not the length. It wasn't really happy with a Tal RS on it either. If you must have an EQ mount, make it an EQ5 at the least.

At the moment I have my OTA fitted with two knock-off Canon 80-200mm F2.8 lens tripod collars (the only things I've found that are the right size and readily available). These have tripod mount feet and are screwed to a 200mm arca-swiss plate.  I'm using  manfrotto o55c camera tripod legs and a manfrotto 486RC ballhead on which I have replaced the stock quick release clamp with an arca-swiss style screw clamp vice.  Not ideal, it's just barely stable as long as you don't touch it but moving it while observing is out of the question. The long tube applies a lot of torque if you touch the eyepiece.

Is an Eq5 a really big heavy thing (my 486RC ballhead wll fit in a pocket)?

I do have another camera tripod head, a manfrotto pan and tilt head which is bigger and stronger than the ballhead but it isn't arcaswiss compatible which means I'd have to find a way to bolt a QR plate to the bottom of the arca swiss bar.

[digital_davem]

I have the same scope and it sits on a Skytee 2- on the original Prinz wooden tripod ( albeit modified and strengthened) and fitted with the superb Prinz slow motion controls. This is a heavy duty alt-az mount that easily copes with all 3 of my scopes simultaneously. I have forgotten what vibrations at high magnification are.

The EQ3-2 is a lightweight mount really. It could handle the weight of the Prinz, but not the length. It wasn't really happy with a Tal RS on it either. If you must have an EQ mount, make it an EQ5 at the least.

Looked up skytee-2. It looks very impressive but I think the mount, tripod and accessories will cost about 15x what I paid for the telescope - which might be a bit of a gamble!

[John]

Thats the thing about long scopes - the mounts can easily cost quite a lot more than the scope did !

Long tubes exert a force called moment arm on the head of the mount. This basically magnifies movements and vibration so you need a somewhat heavier duty mount head and tripod to control that and keep the tube steady enough to observe at medium to high magnifications.

[digital_davem]

Thats the thing about long scopes - the mounts can easily cost quite a lot more than the scope did !

Long tubes exert a force called moment arm on the head of the mount. This basically magnifies movements and vibration so you need a somewhat heavier duty mount head and tripod to control that and keep the tube steady enough to observe at medium to high magnifications.

Yes, I noticed that when I first tried mounting the scope on my carbon fibre tripod. The head was visibly flexing with the slightest touch. Swapped to the aluminium as the legs mounting plate is a much stronger casting.

[RichM63]

You need to change your Search parameters a little, all Mounts are given load capacities = weight, thus discovering the load capacity for any given mount will give you an idea for your classic telescope if you know the rough weight of it.

If you look at the forum sponsor FLO under the Mounts sections then you can easily work out what range would be good.

Clearly, as in Classic Cars, the owner has to do a little work when looking at 21st Century bits that will work.

Best,

Rich

[philj]

I don't like the EQ2. The dec slow-mo runs out of turn after a while, the dec is sticky when moving without slow-mo and it's a pain in multiple places to move around. (wherever the pointy bits dig in, it also weighs more than twice as much as my scope).

It's usable... But far from comfortable.

I dont either thats why I said eq3/2, an eq2 is too small and wont handle a 3" properly

[philj]

The scope is a 1250mm f16.5

Eq4, 5 or heq5 woukd be the better bet for that then

[Davey-T]

Good question!  I don't know. In my 1976 edition of the Observers book of Astronomy, Patrick Moore says I do...

SPM was probably using setting circles to find stuff back then

Dave

[digital_davem]

You need to change your Search parameters a little, all Mounts are given load capacities = weight, thus discovering the load capacity for any given mount will give you an idea for your classic telescope if you know the rough weight of it.

If you look at the forum sponsor FLO under the Mounts sections then you can easily work out what range would be good.

Clearly, as in Classic Cars, the owner has to do a little work when looking at 21st Century bits that will work.

Best,

Rich

I've been trying to find the specs and for the SW EQ5 deluxe there is nothing at rother valley or First Light that mentions weight capacity.  There was nothing at 5 other shops I tried either, just the same old vague marketing blather. Eventually, I found a shop with some actual specs - it claims to carry 9kg.  My scope weighs 3.2 Kg without eyepieces etc but I'm worried about the torque from the long tube - and also have no idea how to mount the telescope. Pretty sure my arca swiss bar won't fit!

[John]

The weight of the scope will be within the capability of many mounts. It's the length that becomes the major factor and it's really only by comparing experiences that others have with similar instruments that you can find what will work and what won't.

[mikeDnight]

I'm looking for something that will provide a solid dependable mount for my classic 3" refractor with its 41/2 foot long tube. Eq1, Eq2, Eqn what does it all mean in reality?

Cheers

Dave

A classic scope should have a classic mount. I think a good match for your scope would be a early Vixen Super Polaris or the Great Polaris (shown in image). They are no longer manufactured but come up on astro buy sell regularly. Small, light weight and solid, as well as easily transportable. Either would carry your scope well and would look the part too.

[digital_davem]

A classic scope should have a classic mount. I think a good match for your scope would be a early Vixen Super Polaris or the Great Polaris (shown in image). They are no longer manufactured but come up on astro buy sell regularly. Small, light weight and solid, as well as easily transportable. Either would carry your scope well and would look the part too.IMG_20150409_085604.jpg

That mount looks like any other to my untutored eye (i.e. someone who has never seen an EQ mount in the flesh). What are the features that mark it out as classic? It is significantly different from modern mounts? 

ps

That's a neat setup you have there!  Is that a converted garden shed? How does the roof work?

[Roy Challen]

The Vixen SP or GP is basically the blueprint for most of the commercially available mounts around today. The EQ 5 type mounts are the direct equivalents. The others are scaled up or down. Apparently it has ball bearings for both axes (a lot of cheaper mounts don't eg SkyWatcher EQ3-2). It was made in a time when quality meant as much a profit did.

If I didn't have my SkyTee I would be looking for a Vixen GP for certain. They do look the part!

[digital_davem]

The Vixen SP or GP is basically the blueprint for most of the commercially available mounts around today. The EQ 5 type mounts are the direct equivalents. The others are scaled up or down. Apparently it has ball bearings for both axes (a lot of cheaper mounts don't eg SkyWatcher EQ3-2). It was made in a time when quality meant as much a profit did.

If I didn't have my SkyTee I would be looking for a Vixen GP for certain. They do look the part!

It looks very smart and hunky in that pic.

Another question - how to mounts attach to the tripod or pillar - is it a standard fitting like camera mounts or are they all different?

[Roy Challen]

The mount attaches to a base plate via a big bolt through the middle of the plate. The plate attaches to the tripod via three yokes with big bolts through them. Usually.