Author Topic: Vixen Mini Porta?  (Read 402 times)

tyrrcencifunc

  • Active Astronomer
  • ***
  • Posts: 129
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Vixen Mini Porta?
« on: December 31, 2017, 07:40:36 PM »
Has anyone had direct experience with the Vixen Porta II and/or Vixen Mini Porta mounts? The reason I ask is because I would like to know how steady the altitude position is in use.
I tried mounting a Sky-Watcher ST80 on a Sky-Watcher AZ3 mount/tripod, and although it seemed capable, I quickly discovered that the altitude bolt worked loose after only a few minutes of use. The telescope OTA would eventually and consistently slide back to point up at the zenith, no matter how hard I tightened the bolt, making it virtually unusable for regular astronomical use.
I’m guessing the lock-washer wasn’t up to the task or faulty in some way. Although I’ve since found out that I’m not the only one to suffer from this particular problem with the AZ3. I don’t have the AZ3 now and I’m considering a Vixen Mini Porta. Does anyone know if it suffers from the same defect/problem?

Thanks.



Ryan Lawlor

  • Active Astronomer
  • ***
  • Posts: 122
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #1 on: December 31, 2017, 11:40:12 PM »
I used to own the Mini Porta and used it for over a year in conjunction with the VMC 95L, which was 4 lbs total (using the built-in flip mirror instead of an external diagonal and also the stock RDF). I also used Meade 4000 plossls with it.

The Mini Porta really is intended to be a very lightweight, ultraportable mount. The Vixen Optics site says the load capacity listed as high as 8 lbs and that is wrong. The manual itself lists the capacity as just over 6 lbs and, based on my experience, I feel that is about right. The mount handled the 4 lb VMC95L adequately when properly balanced (remember, I only used plossls too). Vibrations stopped after a second or two. Wind and passing cars would shake the mount (again--it is very light) so I got in the habit of actually using the EP tray with EPs and my flashlight to add weight and stability. I will say that due to the RDF I generally didn't observe objects at or near zenith much but I don't think it would have been an issue.

If I were in your shoes knowing what I know, I'd go for the big brother Porta II (if you're determined to stick with the Vixen line). Looking at your scope, you've got rings, a RACI finder and bracket, and also a diagonal all adding weight. Add in an EP and I imagine you'll be right at the 5-6 lb limit. It might be fine but it might not--especially at zenith with heavier EPs. Get the Porta and it just isn't even a question. Plus, the plastic slo mo controls that come with the Mini Porta really are junk. After springing for two flexible slo mo cables you won't have saved all that much over a Porta II anyway.

Cheers,
Pauly

Nate Flores

  • Active Astronomer
  • ***
  • Posts: 127
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #2 on: January 04, 2018, 04:58:11 AM »
The best way to mount a scope is to have the altitude axis go through the center of the OTA. This will insure constant balance regardless of the direction or orientation of the scope. Your picture shows a scope with the altitude axis several inches BELOW the center of the OTA. BAD!!!

Tommy Schmidt

  • Active Astronomer
  • ***
  • Posts: 122
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #3 on: January 05, 2018, 04:29:52 PM »
Quote
I used to own the Mini Porta and used it for over a year in conjunction with the VMC 95L, which was 4 lbs total (using the built-in flip mirror instead of an external diagonal and also the stock RDF). I also used Meade 4000 plossls with it.

The Mini Porta really is intended to be a very lightweight, ultraportable mount. The Vixen Optics site says the load capacity listed as high as 8 lbs and that is wrong. The manual itself lists the capacity as just over 6 lbs and, based on my experience, I feel that is about right. The mount handled the 4 lb VMC95L adequately when properly balanced (remember, I only used plossls too). Vibrations stopped after a second or two. Wind and passing cars would shake the mount (again--it is very light) so I got in the habit of actually using the EP tray with EPs and my flashlight to add weight and stability. I will say that due to the RDF I generally didn't observe objects at or near zenith much but I don't think it would have been an issue.

If I were in your shoes knowing what I know, I'd go for the big brother Porta II (if you're determined to stick with the Vixen line). Looking at your scope, you've got rings, a RACI finder and bracket, and also a diagonal all adding weight. Add in an EP and I imagine you'll be right at the 5-6 lb limit. It might be fine but it might not--especially at zenith with heavier EPs. Get the Porta and it just isn't even a question. Plus, the plastic slo mo controls that come with the Mini Porta really are junk. After springing for two flexible slo mo cables you won't have saved all that much over a Porta II anyway.

Cheers,
Pauly

Thanks for your reply Pauly. I was rather concerned about the overall light weight of the Mini Porta. I believe Vixen state a 3.5 kg top load for it to bear. I think you're probably right about the bigger Porta II. I will give it some consideration.

Anthony Cejudo

  • Active Astronomer
  • ***
  • Posts: 120
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #4 on: January 10, 2018, 09:30:51 AM »
Quote
The best way to mount a scope is to have the altitude axis go through the center of the OTA. This will insure constant balance regardless of the direction or orientation of the scope. Your picture shows a scope with the altitude axis several inches BELOW the center of the OTA. BAD!!!

Sorry, best I could do.

sennessningwilch

  • Active Astronomer
  • ***
  • Posts: 133
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #5 on: January 13, 2018, 01:53:53 AM »
Shorty Barlow,
I use my Orion ST80 on a Vixen Mini Porta and find altitude drift to be no problem. To me the combo is ideal for low weight and portability. I would not use any OTA larger or heavier than a ST80 with its stock 1-1/4" focuser though.
Bill

Fred Lafever

  • Active Astronomer
  • ***
  • Posts: 123
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #6 on: January 13, 2018, 06:27:34 AM »
Quote
Shorty Barlow,
I use my Orion ST80 on a Vixen Mini Porta and find altitude drift to be no problem. To me the combo is ideal for low weight and portability. I would not use any OTA larger or heavier than a ST80 with its stock 1-1/4" focuser though.
Bill

OK, thanks Bill. I have a physical disability and I am partially paralysed in the right arm and leg. Is the Mini Porta quite easy to carry? I have no problems carrying an AZ3 or EQ3-2 tripod. And thanks for the head's up on the altitude drift.

malralilin

  • Active Astronomer
  • ***
  • Posts: 131
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #7 on: January 13, 2018, 09:45:20 PM »
I am 71 years old and not in very good shape but can move the assembled Mini Porta and ST80 combo easily with one hand.
Bill

Jose Lukeson

  • Active Astronomer
  • ***
  • Posts: 119
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #8 on: January 15, 2018, 08:17:38 PM »
I have the Vixen Porta II. I mount the Celestron SCT5 and Lunt 50mm solar scope to it with dovetails. I haven't had any problems with Alt or Az holding firm. Only issue was I broke oneof the original control/adjustment arms. Replaced both with new stronger control arms and I've been good for 2 years. The tripod is very sturdy with this setup. My scopes are relatively light weight so maybe that helps.

Rahul Sanders

  • Active Astronomer
  • ***
  • Posts: 126
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #9 on: January 18, 2018, 02:54:48 AM »
Quote
I am 71 years old and not in very good shape but can move the assembled Mini Porta and ST80 combo easily with one hand.
Bill

Thanks for the reply Bill.
As you can see from my jpeg I plan to use an Orion 9x50 RACI finder with the ST80. Along with the weight of the diagonal I plan to use fairly normal sized 31.75mm (1.25") eyepieces (including TeleVue Plossls) sometimes in combination with a Barlow.

Do you think the Mini Porta will support the combined weight well?

Sam Citadelle

  • Active Astronomer
  • ***
  • Posts: 128
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #10 on: January 25, 2018, 09:10:46 PM »
Quote
As you can see from my jpeg I plan to use an Orion 9x50 RACI finder with the ST80. Along with the weight of the diagonal I plan to use fairly normal sized 31.75mm (1.25") eyepieces (including TeleVue Plossls) sometimes in combination with a Barlow.

Do you think the Mini Porta will support the combined weight well?
I often use an ES 1.25" 24mm 68 degree (11.6oz; 329g) eyepiece, a 1.25" mirror diagonal and an Orion 6X30mm RACI finder and find this weight is handled nicely on the Mini Porta. I decided to get out the bathroom scales and weigh myself with and without the scope, mount/tripod and accessories and found that this "Grab and Go" combination to be about 14 lbs. or 6.4 kg.

Additionally, I have an original Porta which I use with a Celestron 80ED and a Vixen A80Mf refractors. I really like the Porta but it is about twice the weight of the Mini Porta. The Porta is physically larger and much more unwieldy which means that I need two hands when carrying the Porta and refractor.

David Patel

  • Active Astronomer
  • ***
  • Posts: 132
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #11 on: January 31, 2018, 12:11:25 AM »
Shorty Barlow, mine stated weight is 5.4kg and can handle a 9kg load. I haven't weighed the setup, but this seems accurate. I can carry the tripod and mount in one hand, twois easier. One feature I haven't resolved for me personally, how to lock down the mount during transport. The mount has a hex head screw to tighten it down, but I never tighten it. My inconvenience, not a bad design. Ive thought about attaching a knob to this screw, similar to Bob's knobs. I love the mount and tripod. I have my solar scope always on the mount. I can transport this scope setup easily to my yard for quick viewing. A great grab and go setup that is sturdy, adjustible in height, and smooth operation.

Jason Pederes

  • Active Astronomer
  • ***
  • Posts: 129
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #12 on: January 31, 2018, 10:46:47 AM »
Quote
Quote
As you can see from my jpeg I plan to use an Orion 9x50 RACI finder with the ST80. Along with the weight of the diagonal I plan to use fairly normal sized 31.75mm (1.25") eyepieces (including TeleVue Plossls) sometimes in combination with a Barlow.

Do you think the Mini Porta will support the combined weight well?
I often use an ES 1.25" 24mm 68 degree (11.6oz; 329g) eyepiece, a 1.25" mirror diagonal and an Orion 6X30mm RACI finder and find this weight is handled nicely on the Mini Porta. I decided to get out the bathroom scales and weigh myself with and without the scope, mount/tripod and accessories and found that this "Grab and Go" combination to be about 14 lbs. or 6.4 kg.

Additionally, I have an original Porta which I use with a Celestron 80ED and a Vixen A80Mf refractors. I really like the Porta but it is about twice the weight of the Mini Porta. The Porta is physically larger and much more unwieldy which means that I need two hands when carrying the Porta and refractor.
OK thanks. I'd almost certainly carry the ST80 and the Vixen mount/tripod separately due to my disability. How would you say the original Porta, which I believe is roughly the same weight as the Porta II, compare in weight and transportability compared with a regular AZ3/AZ4 tripod? Is it much heavier to manipulate? Bearing in mind, I'm only really planning on carrying the Vixen in my garden.

percufareg

  • Active Astronomer
  • ***
  • Posts: 125
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #13 on: February 02, 2018, 07:02:50 PM »
Quote
Shorty Barlow, mine stated weight is 5.4kg and can handle a 9kg load. I haven't weighed the setup, but this seems accurate. I can carry the tripod and mount in one hand, twois easier. One feature I haven't resolved for me personally, how to lock down the mount during transport. The mount has a hex head screw to tighten it down, but I never tighten it. My inconvenience, not a bad design. Ive thought about attaching a knob to this screw, similar to Bob's knobs. I love the mount and tripod. I have my solar scope always on the mount. I can transport this scope setup easily to my yard for quick viewing. A great grab and go setup that is sturdy, adjustible in height, and smooth operation.

Thanks. I was wondering about the transportability of it.
This tripod above is for my 235mm Celestron Evolution SCT. It is about 11 kg. It is not easy for me to carry, although I can pick it up with only my left arm/hand.

So the Porta II is approximately half this weight I guess. I think it should be easy enough for me to carry, especially in a carry case. I only intend to use it in my back garden anyway.

Jim Snyder

  • Active Astronomer
  • ***
  • Posts: 121
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Vixen Mini Porta?
« Reply #14 on: February 09, 2018, 06:46:45 AM »
OK thanks. I'd almost certainly carry the ST80 and the Vixen mount/tripod separately due to my disability. How would you say the original Porta, which I believe is roughly the same weight as the Porta II, compare in weight and transportability compared with a regular AZ3/AZ4 tripod? Is it much heavier to manipulate? Bearing in mind, I'm only really planning on carrying the Vixen in my garden.
Shorty Barlow,
I have no experience with an AZ3/AZ4 tripod.
Bill