Filters will not thread on New 30mm ES ep

My 2" filters: Orion Ultrablock and Celestron OIII
My 2" eyepieces: ES 9mm and 14mm, and Televue 26mm Nagler

I've had no problems threading either filter onto any of my eyepieces.

I also have an ES 6.7mm eyepiece and a 1 1/4" Ultrablock filter...no problems with threading there, either.

In the spec at Explore Scientific site they specified that the barrel of the 82° series accepts standard filters . . . .

Don't you just love it when a factory rep doesn't have a clue as to what the factory produces?

I tested my filters on an ES 14mm 100' and they all work fine as well. To be fair here to ES I have had other EPs which were a bit sticky with filters - Baader Hyperions for instance.

It seems there is a variation in thread pitches in astro filters and barrels - why am I not surprised - hardly anything in astro ever fits together the way you might wish for but thats hardly the fault of ES alone.

this is the all too famous human factor...

I've had a Orion Skyglow not thread onto any 2" eyepeice I've got, and an Orion Ultrablock and Skyglow Astrophotography filter thread on everything just fine. All I can conclude is that Orion filters are inconsistent.

I bought a 2" filter cell from ebay for the ones that didn't work, moved the glass over to a new cell, and all is fine now. I shouldn't have to do this, but I had the filter already, and returning it was more hassle than just getting a new cell.

I tested my filters on an ES 14mm 100' and they all work fine as well. To be fair here to ES I have had other EPs which were a bit sticky with filters - Baader Hyperions for instance.

It seems there is a variation in thread pitches in astro filters and barrels - why am I not surprised - hardly anything in astro ever fits together the way you might wish for but thats hardly the fault of ES alone.

You know, so far my Hyperions haven't given me any trouble yet, though I don't have any Orion filters anymore.

As for the inconsistency, I believe the thread pitch is pretty standard. Where I believe the trouble is coming in is two different thread "standards" wrt the ramp shoulder depth - depth of the thread cut between O.D. and I.D.

Orion eyepieces and filters for one example seem to have a shallower shoulder, which explains why their eyepieces have no problems with any filters, theirs or other brands. But many eyepieces, especially those machined to more exacting tolerances, and using the deeper cut threads will have trouble threading Orion and other filters cut to the other "standard".

Well, I tried my ES 30mm 82 degree with a Lumicon OIII filter and can confirm that yes, the filter just didn't want to go on. The eyepiece as Explore Scientific replied to me in an email is threaded for filters but they just don't like go on there. I put the filter on the Paracorr Type I I used (silver lettering, last model of the Type I) and it worked fine. Lots of weight on the dob with those two items but the counter balance worked fine.

When this thread came out I inquired to ES and this was the reply that I received:


"The eyepiece barrel is threaded. We do not offer a filter to go with our eyepieces, but they are internally threaded. Let me know if you have any further questions."

All I can say is that if you have to rely on the threads on the ES 30mm 82 degree, you are going to have to work on them. The 2 inch Ultrablock I have also had a hard time going on. I just purchased my eyepiece and so perhaps this is with the newer versions.

Anyone having trouble fitting 2" filters on ES eyepieces?
I just received my new ES 82°-30mm eyepiece and am having trouble threading any one of my 2" filters. I own several other ES eyepieces but this is the only 2" ES eyepiece I own so I can't compare.
The filters thread fine on all my other 2" non-ES eyepieces.

I checked for barrel roundness and it's fine. I noticed the threads seemed very fine and did not seem to be cut deeply. That seemed to be the problem.

I will contact the vendor this morning to see if this can be exchanged.
I was just wondering if anyone else had a similar problem.

Thanks!

In days of yore there was a problem with some Meade eyepieces and the threaded filters out there.

If you're using a Newt, it has to fit the eyepieces.

If you're using an sct/refractor at a minimum the threads should fit the diagonal and if you have a Newt too, well, you want it to fit the eyepieces.

Greg N

I had a chat with an ES rep who told me my Orion 2" filters "should" fit. I assured him that they did not fit my ES eyepieces but would fit my other 2" EP's just fine so I thought there was an issue with the threading on ES 2" EP's. The ES rep didn't seem too concerned that I was having a problem with their products. He just kind of tap danced around the issue and wasn't really much help.

I tried my Skywatcher OIII last night on my new 30mm ES and it would only screw on by approx half a complete turn. It jammed so tight I started to panic thinking I had damaged the thread. It spins on freely on any of my other TV or Pentax ep's!

My 2" Celestron OIII filter doesn't screw onto my new 30mm easily, but my Baader tuning rings "spin" on without any effort.

Oddly enough, the filter screws onto the rings just as easily as the rings go onto the EP...

My 2" Celestron O-III filter, (which is really made by Baader), would screw onto my 2" Antares Twist Lock adapters, but I would have problems trying to get it to screw onto some of my 2" eyepieces, so I took the 2" Celestron O-III filter out of the cell and I switched it with my Orion 2" 13% Neutral density filter....I basically switched the filters out from each cell.

When doing this, it was difficult as I had to make sure that I didn't "cross thread" the retaining rings back onto the cells. A good strong pair of glasses helped in doing this.

Now my Celestron O-III filter with the Orion filter cell, screws onto all of my eyepieces easily.

I don't use my 13% Moon filter that much, so all is good. I also tried screwing the moon filter, with the New O-III cell onto all of my eyepieces and it goes on a bit better now...go figure, LOL!

I took pics of both filter cells and you can clearly see that the Celestron threads on the original O-III filter cell is slightly more narrow than the Orion one.

Cheers,

I think ES eyepieces are excellent in all regards except they screwed up their filter threads.

I think ES eyepieces are excellent in all regards except they screwed up their filter threads.

Certainly isn't what I've experienced. As I mentioned, all my filters screw on my ES30 very smoothly. There must have been a few that the filter threads are not up to standard, but that doesn't apply to all ES eyepieces. Also, with their warranty, buyers can certainly be covered in case their eyepiece threads are bad. As mentioned, sometimes the fault lies with the filter, not the eyepiece. Orion was one that was very tempramental to thread onto all of my eyepieces, including ES, TV, Pentax.

That was pun intended, btw.
What annoyed me was of the several different 2" ep's I've owned over the years this particular ep was the first that ever gave me this sort of problem. And now I'm finding out others are also having similar issues.

Hey Tank, I bought one of the old style 30mm ES 82 series eyepieces from Woodland Hills. I used the link you provided. Thank you for the link! We now return to our regularly scheduled programing.

It's not ES, at least in our case. We got the 2" Orion Ultrablock and 13% moon filter, two of each for BVing. Amongst these 4, one of each pair will thread onto our ISTAR star diagonals and 31mm Baader Aspherics, but the other two filters will not.

Hey Tank, I bought one of the old style 30mm ES 82 series eyepieces from Woodland Hills. I used the link you provided. Thank you for the link! We now return to our regularly scheduled programing.

Oh yes, and if the filters don't fit---Smash'em!!

I think ES eyepieces are excellent in all regards except they screwed up their filter threads.

Certainly isn't what I've experienced. As I mentioned, all my filters screw on my ES30 very smoothly. There must have been a few that the filter threads are not up to standard, but that doesn't apply to all ES eyepieces. Also, with their warranty, buyers can certainly be covered in case their eyepiece threads are bad. As mentioned, sometimes the fault lies with the filter, not the eyepiece. Orion was one that was very tempramental to thread onto all of my eyepieces, including ES, TV, Pentax.

My experience is that 2 inch filters are pretty touchy, the threads are large diameter and fine and the material is very thin, it all adds up to variations between filters and eyepieces.

Like Mark's, my 2 inch Celestron O-III is also particularly touchy, it is very tight on the 31mm Nagler, fits nicely on the 20mm... My 2 inch Ultrablock is also pretty tight in some, a reasonable fit in others.

Jon

It's not ES, at least in our case. We got the 2" Orion Ultrablock and 13% moon filter, two of each for BVing. Amongst these 4, one of each pair will thread onto our ISTAR star diagonals and 31mm Baader Aspherics, but the other two filters will not.

Exactly, it's the Orion filters.

I have had trouble threading my Orion filters onto my ES eyepieces at times. I used a Lumicon filter last time out and it threaded onto my ES 30 no problem. I agree that the Orion filters have thread issues.
Barry

A couple years ago I talked to the production manager at Lumicon. he said that he considered the Lumicon filter threads to be a little undersized, but that it was necessary because a sample of 500 eyepieces showed a HUGE variation in I.D., thread depth, thread cut cleanliness, etc.
So they used the smallest size they measured to determine the thread size they needed, and as a result, never had a customer complain about a non-fit.

Through the years I've had other brands of filters that also didn't fit (it's a REALLY common problem with Orion filters), and here is what I've done:
--use an eyepiece with a steel or brass barrel, not aluminum
--thread the filter in until it catches.
--force the filter 1/8 turn further and then back the filter out completely.
--thread the filter in until it catches
--repeat the 1/8 turn further routine until the filter threads into the eyepiece.

In such a way, the filter is essentially being 'rethreaded' by the action similar to how a tap works to thread a hole.

Long before the Scots were considered thrifty, the Dutch were considered tight with their money. A machinist friend of mine refers to this as a "Dutchman's Thread Chase" because it's cheap and easy to do--especially while watching TV.

My Orion filters all thread in all the way....now.

Don,
That is basically what I did with my Orion filters and ES eyepieces. I just kept threading them in and out until they went on smoothly. I do sometimes still have trouble getting the threads to catch but once they do I can thread them on fine.
Barry

Thanks Don, bherv. Will do.

I have a ES100 14mm and orion moon filter and ultablock filter. Both filters thread onto the ES ep easily...in fact easier than on my E21.

Time to resurrect this thread!

I just tried threading my 2" Orion Ultrablock onto my 34mm ES 68 and it was a bit touchy at first, but once I got it to catch, it threaded all of the way on!

Cheers,