Televue Equalizer 2" to1.25" Focuser Adapter

[scarp15]

Since I started to use a dobsonian, one aspect that I found to be a little frustrating was when changing eyepieces from hefty 2" to light, in my case, 1.25" eyepieces and often loosing the target image due to the alteration in balance. This re-balance issue was reduced slightly with both my former and current dobsonian scope, by applying the necessary amount of friction to the brake. However targets became more awkward to keep aligned during switching, for example, when positioning the scope to view near to the zenith. I do not employ the addition of weights in balancing my scope.

My eyepieces currently range from quite hefty low power 2", weighing in at 17oz and 27oz respectively, to medium / high power 1.25", from 7.5oz, 8oz, and 10oz. The Televue Equalizer works by addressing this re-balancing variation. 

Weighing 12oz, it is made of solid brass, complete with a brass non marring clamp ring. The design is high hat, not as flush / compact as standard adapters, adding perhaps a fraction more focus travel to the eyepiece. Besides being quite heavy, it is also quite shinny. However the base is tapered so as to reflect light to the sides, therefore it does not require blackening. It is very nicely engineered and comes complete with a dust plug.

I have so far had five opportunities to use this, involving my former 12" Skywatcher Flextube and current OOUK VX14 mounted on an OOUK dobsonian base. I will base this general assessment on my most recent session. I ought to point out that all my eyepieces used are wide field 82 degree, so I do not know how effective this will work with 52 degree plossls for example.

In use, I found it necessary to apply a degree of extra tensioning to the brake prior to changing the e.p. However when a target was centered, regardless of its elevation, it rarely completely left the frame of the replacement eyepiece. I found that it is required to be realigned back to the centre, as the image slips somewhat to the edge of the field of view but nothing more. I always check the position of an object with my telrad just in case, but having not to be particularly concerned about relocating a lost image after switching to a high power eyepiece, is an advantage in terms of time and effort.

As I have indicated, my eyepiece collection is currently quite systematic in weight terms, low power are heavy 2" and medium, high power are light 1.25", so I feel that this is completely compatible concerning my own observing requirements. If using a mix of feather weight plossls with narrow fields and heavy 1.25" high power e.p's etc, I do not know how effectively this adapter will perform. I like the high hat design and this is compatible with my William Optics focuser extension tube, which does not have a slot for accepting standard adapter 1.25" thumb screws. One eyepiece I use with a slightly longer barrel, 7mm Nagler T6, just falls shy of slotting snuggly flush into the adapter. It does not affect the performance though.

[scarp15]

I would just like to add a couple of corrections and additional comments based on my account. Firstly the adapter is actually constructed out of solid bronze and not brass as stated. I made a reference to the longer barrel on a 7mm nagler. In retrospect there is no issue in achieving a good fit. I believe that the high hat design is a safety feature to ensure that the barrel of certain eyepieces will not scratch the mirror, particularly if used in some types of star diagonals.

[NGC 1502]

Thanks for the review Iain.

I suppose TeleVue came up with the Equaliser because their own EPs vary so much in weight, but obviously useful with any make.

I like simple solutions to problems

Regards, Ed.

[jetstream]

Since I started to use a dobsonian, one aspect that I found to be a little frustrating was when changing eyepieces from hefty 2" to light, in my case, 1.25" eyepieces and often loosing the target image due to the alteration in balance. This re-balance issue was reduced slightly with both my former and current dobsonian scope, by applying the necessary amount of friction to the brake. However targets became more awkward to keep aligned during switching, for example, when positioning the scope to view near to the zenith. I do not employ the addition of weights in balancing my scope.

My eyepieces currently range from quite hefty low power 2", weighing in at 17oz and 27oz respectively, to medium / high power 1.25", from 7.5oz, 8oz, and 10oz. The Televue Equalizer works by addressing this re-balancing variation. 

Weighing 12oz, it is made of solid brass, complete with a brass non marring clamp ring. The design is high hat, not as flush / compact as standard adapters, adding perhaps a fraction more focus travel to the eyepiece. Besides being quite heavy, it is also quite shinny. However the base is tapered so as to reflect light to the sides, therefore it does not require blackening. It is very nicely engineered and comes complete with a dust plug.

I have so far had five opportunities to use this, involving my former 12" Skywatcher Flextube and current OOUK VX14 mounted on an OOUK dobsonian base. I will base this general assessment on my most recent session. I ought to point out that all my eyepieces used are wide field 82 degree, so I do not know how effective this will work with 52 degree plossls for example.

In use, I found it necessary to apply a degree of extra tensioning to the brake prior to changing the e.p. However when a target was centered, regardless of its elevation, it rarely completely left the frame of the replacement eyepiece. I found that it is required to be realigned back to the centre, as the image slips somewhat to the edge of the field of view but nothing more. I always check the position of an object with my telrad just in case, but having not to be particularly concerned about relocating a lost image after switching to a high power eyepiece, is an advantage in terms of time and effort.

As I have indicated, my eyepiece collection is currently quite systematic in weight terms, low power are heavy 2" and medium, high power are light 1.25", so I feel that this is completely compatible concerning my own observing requirements. If using a mix of feather weight plossls with narrow fields and heavy 1.25" high power e.p's etc, I do not know how effectively this adapter will perform. I like the high hat design and this is compatible with my William Optics focuser extension tube, which does not have a slot for accepting standard adapter 1.25" thumb screws. One eyepiece I use with a slightly longer barrel, 7mm Nagler T6, just falls shy of slotting snuggly flush into the adapter. It does not affect the performance though.

Scarp thanks for the heads up,I'm going to get one for my orthos-balance will be very close to my TV's

[scarp15]

Gerry, look forward to learning how you get on, it should certainly correct balance issues with your orthos. I would not want to go back to using just the standard 1.25" adapter. I always have a medium / high power eyepiece ready in the equalizer adapter for the change over.

[scarp15]

Thanks for the review Iain.

I suppose TeleVue came up with the Equaliser because their own EPs vary so much in weight, but obviously useful with any make.

I like simple solutions to problems

Regards, Ed.

Ed yes it ought to work with any make of e.p. I would  expect. Completely agree, simple is best.

[Moonshane]

looks a great product. I just add a small box filled with 2ps and 1ps at the mirror end and this seems to prevent balance issues. I tuck it into the mirror cell.

[clubjoker]

Thank you for the informative review, and the great photos. It's really difficult to find useful information on these smaller astro accessories on the web. For some reason, the manufacturers and retailers conspire to make them all a mystery in terms of specification, and a bit of a gamble to buy.

Looks very useful.

[Dyptorden]

Hi scarp15,

Could you tell us please whether the Equalizer has threads to attach 2" filters?

In case it has threads, how is the distance from one side to the other... I mean ... is there any chance to break the filter if using an eyepiece with a longer barrel?

Thank you,

[John]

Tele Vue don't normally put filter theads on their 2" - 1.25" adapters.

[spaceboy]

I had one of these some years ago and agree they are handy for equalizing the weights between 1.25" and 2" changes. I was a bit disappointed that they don't thread for filters and this was one of the reasons I let mine go along with the rather shiny surface. In hindsight I wish I'd kept it as it would have been a winner for use in my AR127L as the OTA is aluminium and my magnetic counter weight mod is a bust.

Dibs on the Equalizer if you decide it's not for you Scarp

[scarp15]

I still get to use mine quite a lot, I do not use quite as many light weight 1.25" e.p's as I did when I compiled the review, yet I find that it is still a usual balancing aid for those that would benefit from it. I like the high hat design as it is fully compatible for using my Ethos e.p's should I wish to use them in this format. 2" filters, I attach to my paracorr or alternatively, extension tube.

Therefore the Equalizer is not threaded for filter use and sorry not for sale anytime soon.

[Dyptorden]

Probably off topic... and if so, I am deeply sorry and will remove the post. But could you please tell me how can I use 2" filters with my 1.25" oculars (and be sure I won't break the filters with the barrels)? Thank you!

[Moonshane]

http://stargazerslounge.com/topic/84086-novel-use-for-baader-fine-tuning-rings/