Louis D

On 23/07/2019 at 19:05, Stickfarm8 said:

The service on that order was excellent and even with DHL shipping, the cost was competitive with pricing for a similar cable from the only vendor here in the US that the retailer I purchased the mount and scope had recommended.

Welcome to SGL from a fellow 'Merican. 🤠

Thankfully, the US doesn't generally charge import duties on items under $800 and most states expect you collect the sales tax yourself and remit it, which pretty much no one does.  That, and the GBP to USD exchange rate is excellent right now.  I've bought a fair amount from Britain lately because of all these reasons.

6 hours ago, Alfian said:

The first was a 20mm erecting image eyepiece which by design is already compromised for astronomical use.

A contributor on CN did a tear down and rebuild of the Celestron 20mm erecting eyepiece.  It's quite an interesting read.

On 23/07/2019 at 09:45, joe1950 said:

Do microscopes and parts not use antireflection coatings? Everywhere I look at microscope eyepieces, not a word is mentioned about coatings.

I'll have to double check, but as I recall, most AO and B&L microscope eyepieces were singly coated with magnesium fluoride (light violet) back in the 60s and 70s.  Russian made microscope eyepieces of the 90s were more complexly coated and appeared green with hints of other colors.  I don't know about modern, Chinese or Japanese made microscope eyepieces.  I'm sure high end microscope eyepieces from Zeiss, Leica, Nikon, and Olympus are fully multicoated.

On 23/07/2019 at 08:16, Alfian said:

As someone who cut my astronomical teeth on a Celestron 130eq I can only strongly reinforce the need to upgrade the supplied EPs as soon as possible.

Never having bought an entry level telescope kit, and for the edification of future readers, could you expand upon what eyepieces come with the 130EQ and what makes them so bad?

There's also the 5mm BST Starguider from FLO, our forum sponsor.  I have the Paradigm version, and it seems quite sharp across the field.  I'll have to spend more time comparing it to some other eyepieces I have in that power range, but initially, it seems quite good.  If you pick up a used one and don't like it, it should be quite easy to sell it along without much of a loss.

12 hours ago, strayring said:

Followed Red Henry's design ideas for the 2", some people call it a di-plossl, I'm really not sure though.

I was going to say, it sounds a lot like CN's Martin Pond's "di-plossl".

9 hours ago, joe1950 said:

What I can’t confirm and am growing suspicious of, Rusted, is the existence of that which is called the Milky Way! Now I have an open mind. I’ve seen photos of this. But even when the skies are totally clear, I’ve not seen it in decades! Not a trace. It may have existed at one time, but where did it go? 🥴

I used to live withing 2 hours of NYC, and I can confirm the MW is a no-show there.  Your best bet from your location would be to head 5 hours NW to the area north of State College, PA, near Keating, PA.  That area is around a Bortle 2/3, so you should be able to see the MW from there.

17 hours ago, Jarvo said:

Where have the last 10 years gone !

Jarvo

So, do you still have and use the 32mm TV Plossl after all these years?  I still have my 5.2mm Pentax XL from 1998 that I use regularly.  The 14mm XL has been supplanted by multiple others in that range, as has my 9mm Vixen LV, both from 1997/1998 when I started out.

On 12/07/2019 at 13:04, Don Pensack said:

Since the light rays after the Powermate are parallel, it should probably go first since getting the eyepiece correctly placed relative to the Paracorr lens is critical for best coma correction.

FWIW, my best lifetime view of Jupiter was with PowerMate + Paracorr + 8mm Ethos, at 456x, in literally perfect seeing (Pickering 10).

If you look a few posts down from the one you quoted, I corrected myself after some research with the Wayback Machine :

Richard Keppler asks about positioning the new 4x Powermate with a
Paracorr. Which goes first?

Unlike the 2x Big Barlow which must go ahead of the Paracorr, either way
is fine with the 4x Powermate and either way is approximately parfocal
for most eyepieces.

Nick Black asks if there are any problems using a Big Barlow with a
Paracorr.

Not if you place the Big Barlow ahead of the Paracorr. In other words,
eyepieces should always go directly into the Paracorr when using a Big
Barlow. Since the 2" Big Barlow won't slip all the way into the
Paracorr, it does not reach its parfocal point and changes the Paracorr
correction.

As an aside, you can place Tele Vue 1.25" Barlows or Powermate into the
Paracorr because these are parfocal devices.

Which then raises the question of how to use the Big Barlow with SIPS.

14 hours ago, MarsG76 said:

After a long time I finally had a chance to do some good fashioned observing and I noticed something that is VERY surprising.... I spent most of the time observing Jupiter than Saturn, trying to pick-out as much details as possible... I was observing them through my 14" Skywatcher with a Televue 11mm Nagler Type 6 eyepiece and 2X Powermate.. the views were great and detailed, fine detail in Jupiter, the GRS as clear as the nose on my face and a shadow of Io on the NEB.. but this is not what this post is about....

During Saturn observation I replaced the 2X PM with the Celestron 2X Barlow out of curiosity, the Ultima version, and to my surprise even at the same magnification the Barlow showed more detail.?!?!?!?!.. it was only a slight improvement but a visible improvement nonetheless .. I always thought that TV was the premium equipment but the Celestron barlow had the edge on clarity, stability and details.... 

Your next experiment should be to compare the 11mm+2x combos with premium 4.5mm to 6mm eyepieces to see which is better.  I've found my 3.5mm Pentax XW and 5.2mm Pentax XL to perform better contrast and sharpness wise than barlowing any of my 10mm to 12mm premium eyepieces.  It's close with the best Japanese made barlows from the 90s, but the designed together combinations (negative-positive eyepiece designs) still work better.  I don't have any short focal length, positive-only eyepieces like orthos or monos to compare because even at a 1mm exit pupil, I still see some residual issues with my observing eye's massive astigmatism so I wear eyeglasses at the eyepiece even at high powers.  By 0.7mm the effect is largely gone, but floaters then become a huge issue for me.

I will say that at highest powers, my 2" GSO ED 2x barlow plus TV PBI combination is not as sharp as my 2" or 1.25" Orion Deluxe fully baffled Japanese barlows, 1.25" TV 2x barlow, or 1.25" Meade 140 APO 2x barlow.  I don't know if it is a case of less is more or that the slight mismatch between the GSO and PBI becomes apparent at high powers, but it is there.  On the other hand, as @John noted above, ordinary barlows noticeably vignette on large field stop eyepieces while the telecentric GSO+PBI combination (Powermate-like) does not and yields beautiful views with widest or near widest field eyepieces.  I have yet to try the Celestron Ultima 2x barlow because everyone over here wants over $50 for them, and I can't justify spending more than $35 on a barlow simply for comparison purposes.

4 hours ago, joe1950 said:

Thank you, Stu! It does work well. Though my hand shakes holding it since there is nothing to hold it against. I have one of those brackets and next time I'll use it.

6AM here! Can't sleep at night and can't stay awake during the day. My clock is out of sync.

Try the technique I've been mastering taking photos of the AFOVs of eyepieces with my cellphone camera.  Put your thumb and index finger around the rim of the eyepiece.  Next, lower your phone until the field stop just pops into view and the image is centered.  Roll your thumb and finger to come into contact with the phone, and then raise and lower your phone using your finger and thumb to maintain a stable connection to the eyepiece and to keep it level and centered with respect to the eyepiece.  I couldn't get decent photos just trying to hover it above the eyepiece.  There are just too many variables at play (pitch, yaw, x/y/z placement) to get a good image.

I have a couple of 2" GSO (Revelation/TPO/OPT) dielectric diagonals that I use with my AT72ED and 127 Mak to good effect.  They're very sturdy and don't seem to degrade the image in any significant manner.  I tried a cheaper 2" diagonal, but it had flexure issues as well as a tendency to tip eyepieces in the holder when tightening them down.

I would pick up a used 1990s Meade 140 2x barlow like this one.  I've A/B compared it with my Televue 2x barlow, and the two are basically identical.  The only low cost barlow I've found that's cleaner is the 1990s Orion Deluxe 2x fully baffled barlow, but it is a monster at 6 inches in length and much more difficult to find.

I like the Meade so much that I've picked up a total of three of them.  One for regular use, one as a backup in case I drop one on cement, and one for reaching focus with a binoviewer.  The fact that the optical nosepiece is threaded in the standard 1.25" eyepiece thread means it can be threaded onto eyepieces or onto the front of binoviewers or star diagonals.

4 hours ago, allen g said:

With it in my 32 nagler in my refractor give amazing views.

How much for your ultra-rare 32 nagler? 😉

On 01/07/2019 at 14:46, Captain Magenta said:

... I’ve thus temporarily evicted my Astrotrac to accommodate them plus my new 3.5mm...

 

I'd be terrified having a cat lurking about behind an open eyepiece case perched on the edge of a table. 😱  The cats I've known over the years have a tendency to bat at things with their paw at random times.

I have a late 90s Lumicon OIII that has given me my best views of many nebula including the Veil nebula which is all but invisible without it from my backyard.

You might also perform a google search against Cloudy Nights for the Pentax XL (SMC) zoom.  Apparently, it's good, but not great like the Leica and Zeiss spotting scope zooms.  I personally like the Celestron Regal or Olivon spotting scope eyepiece.  If you're in the US, MASILMW sells Olivon blems with the magnification numbers reversed for $65 shipped to the CONUS.  They're a major step up from the basic 8-24mm zooms from Celestron/Meade/Zhumell/etc. for about the same money.

24 minutes ago, nhyone said:

I'm fumbling my way with binoviewing on my Mak 127.

I knew magnification would increase due to the longer light path, but I underestimated it. As a result, the image was very dim.

My scope is nominally 1500mm. With binoviewer, it should be ~1700mm, but my crude measurement puts it at 2000mm!

I bought a copy of 8, 10, 12 and 15mm eyepieces. In the end, only the 15mm was really usable. (It is the highest I would use for binoviewing on my scope.)

Still, that's only a 1.33x increase in focal length which is much less than the 3x I get using a 2x barlow nosepiece.  Imagine trying to deal with a 4500mm focal length scope!

I use 23mm Aspherics mostly because they yield just about the widest field at a moderately low power, and they're super light.  If I need higher power, I do have pairs of 19mm Konigs (from binoculars) and 15x microscope eyepieces (16.7mm) and the aforementioned 2x (3x) barlow element.

38 minutes ago, nhyone said:

Hi, you said 18mm HD-60 is similar to Paradigm, but you did not say how good/bad they are.

In past reviews, 18mm was by far the weakest in both lines. Do you feel so?

I'm surprised 15mm performs similarly to the 18mm. Does that means it isn't so good after all?

My takeaway from your review is, Paradigm is good, but it still loses to HD-60 when they go head-to-head. So, prefer to get HD-60 if price is not an issue.

I got the BST 8, 12 and 15mm for my Mak 127. This review doesn't change my mind. 😀

(I would still get the 15mm over the 18mm.)

I just got the 9 and 25mm X-Cel LX. Decided to skip the 6.5mm as it is a little too much mag (230x) for my scope [and I have several ~7mm EPs already!] and the 12mm, cos even if it is much better than the Paradigm, it is a little too low mag (125x) for its intended use (on planets).

The weather hasn't been cooperative for me to get out again, so I'll have to hold off on making any critical assessments for now.

What I will say is that the 18mm HD-60 is pretty weak at the edges compared to the other HD-60s.  From my limited time with the 18mm Paradigm, it is similar, just wider AFOV and much less usable eye relief (7mm less).  I will have to compare them to my 17mm offerings (ES-92, NT4, and AF70) since I don't have any other 18mm eyepieces.  The AF70 is most comparable since it isn't all that well corrected at the edge, either, just 10 degrees wider AFOV.

Head to head, if you don't need the eye relief, the Paradigms have a nicer field stop and similar sharpness to the HD-60s.  They're just narrower in AFOV from 12mm on down.  At 25mm, I found the HD-60 definitely better than the Paradigm despite the latter being wider in AFOV and TFOV.  However, the HD-60 requires so much in-focus that I can't reach focus with it in my 8" Dob with the GSO coma corrector.  I have to take the latter out to reach focus, and then I'm left trying to sort out edge astigmatism from OTA coma.  I haven't tried the 25mm Paradigm in the Dob yet, but I think it reaches focus further out, so it might work just fine in the Dob.

I'll compare the 15mm Paradigm to some of my 14mm eyepieces (Pentax XL, Meade 4000 smoothie, Morpheus) to see how it compares.  The Pentax has significant field curvature, so it should be interesting to see which works better without refocusing.

The problem I've found with eyepiece projection is that few eyepieces, even premium ones, project a flat rather that curved field.  This means that it is difficult to get both the center and edge sharp at the same time.

If you are using afocal eyepiece projection (eyepiece into a camera lens), this works much better because the camera lens's natural depth of focus compensates for the eyepiece's curved image field.  I tend to like my 22mm Astro-Tech AF70 for this method because it is fairly low power, has long enough eye relief to couple with the lens's entry pupil successfully, is well corrected across 95% of the field, and has an easily accessible M43 thread on top to mate with a camera lens (or lens tube) thread.

14 hours ago, Ricochet said:

I think quite a few people do. I remember @Louis D has a pair of Celestron Regals but I think most people choose the Baader MKIII / IV. With my binoviewers the dioptre adjustment twists up and down and can't be locked so a zoom that I need to twist doesn't really appeal. 

I crank my diopter adjusters down snug so they don't rotate with zooming.  Luckily, there isn't enough difference in power between my eyes than I ever need to adjust diopter settings on them or on binoculars.

I couldn't afford two BHZs for the infrequency that I use them.  If you're on the US side of the pond, MASILMW sells the Olivon version of the Celestron Regal Zoom with the zoom numbers reversed on CN classifieds for $65 shipped to CONUS.  MASILMW is Sheldon Faworski of Apogee, Inc fame.  The CR or Olivon zoom is optically about 90% of the BHZ with a couple of distinct physical advantages over it.  One, the top doesn't rotate during zooming, unlike the BHZ, so winged eyeguards can be used; and two, the zoom action is much lighter than the BHZ, so they can be zoomed with fingertip pressure.

I find myself using monovision at the eyepiece more than binoviewers lately due to the simplicity of setup and greater range of possible magnifications.

I'm guessing the exit pupil of the 2x11mm TV Plossl was magnified and brought into focus by the 8mm BST SG.  Inverting the image seems to follow from this diagram I found online:

8 hours ago, vlaiv said:

Indeed! I'm in the market for ~ 5mm-7mm eyepieces for planetary and simply love my ES82 11mm, but at present time, given that ES82 LER would cost me total of about 185e (shipping, import duties, tax, you know, all the nice things government makes you pay ) - that is a bit steep for me.

The US, and Texas in particular, have been minimizing taxes and tariffs on imports to encourage trade.  Too bad it's not being reciprocated.  Off my soap box before John knocks me off of it. 🤐

1 hour ago, vlaiv said:

Bump up ...

Anyone has any news on these now?

I see them stocked again at TS - they were in stock at some point at the beginning and were pulled out of stock - in all likelihood related to first faulty batch. They are back again, but I don't seem to see any further mention online of this "line" (or rather addition to existing line of EPs?).

 

I just bought a set of Paradigms to compare to the HD-60s.  It's your turn to buy some equipment to check out for the rest of us. 😁

Spent some time looking at bright stars and the nearly full moon tonight with the AT72ED and the f/12 127 Mak.  Overall, the two lines more similar than different.

These are my observations in the field flattened 72ED that stuck with me:

1. The 25mm Paradigm falls apart much more quickly than the 25mm HD-60 as an object moves from center to edge.  Perhaps the central 50% is sharp compared to the central 70% to 75% in the HD-60.  The edge in the HD-60 is still usable while the Paradigm is all but unusable.
2. The 18mm HD-60 is quite similar to the 18mm Paradigm as far as sharpness and extent of sharpness, but the HD-60's much more generous eye relief makes it much more eyeglass friendly.
3. The 15mm Paradigm is quite similar to the 18mm in correction and magnification.  It seems a total waste to include it.  Including a 10mm instead of a 15mm or a 9mm and a 7mm instead of an 15mm and an 8mm would have made more sense as far as power progression.
4. The 12mm Paradigm and the 12mm HD-60 are both sharp out to about 80% or more to the edge.  However, both suffer from a bit field curvature requiring refocusing center to edge.  No other focal lengths in either line seemed to improve at the edge with refocusing.
5. The 9mm HD-60 suffers a bit of astigmatic unsharpness at the very edge, but it is hardly noticeable.
6. The 8mm Paradigm and 5mm Paradigm view very similarly.  Both are nearly perfect center to edge. 
7. The 6.5mm and 4.5mm HD-60s view very similarly as well.  Both are nearly perfect center to edge.
8. All the HD-60s have slightly indistinct field stops, with the 6.5mm and 9mm having the least sharp edge.
9. All of the Paradigms seem to have nice sharp field stops.
10. The 25mm Paradigm has very comfortable eye relief with eyeglasses.  The 12mm to 18mm Paradigms are tight but still usable.  However, the 5mm and 8mm Paradigms have super short eye relief that is just about unbearable with eyeglasses.
11. The 18mm and 25mm HD-60s are super comfy with eyeglasses.  The 9mm and 12mm are still comfy, but require being a bit closer.  The 4.5mm and 6.5mm require being in close contact with them to take in the whole field, but it is still easily doable.
12. Stray light seemed equally well controlled in both yielding similar contrast.
13. The 4.5mm to 6.5mm eyepieces were mostly showing false color on bright stars rather than white pinpoints due to pushing the limits of FPL-51 glass.

These are my recollection from using the 127 Mak:

1. All but the 15mm, 18mm, and 25mm versions sharpened up right to the edge.  The 15mm, 18mm, and 25mm versions did improve, but were still unsharp, but to a lesser extent, toward the edge.
2. Eye relief became tighter on all eyepieces for some reason.  The 5mm and 8mm Paradigms required chasing the view because my glasses could not be pushed any further into my eye sockets to compensate.
3. The 25mm versions gave the most pleasing views of the moon due to framing it nicely at a lower power.
4. The 4.5mm to 6.5mm eyepieces were mostly showing diffraction rings on bright stars rather than pinpoints due to the tiny exit pupils.
5. The 4.5mm to 12mm eyepieces were basically sharp center to edge.  Field curvature didn't appear to be much of an issue with either 12mm.
6. Field stops, stray light control, and contrast remained about the same as in the 72ED.

Overall, I'd have to give the nod to the HD-60s for eyeglasses wearers like myself.  If you don't need to wear eyeglasses, the win would seem to go to the Paradigms except at 25mm where the HD-60 is noticeably better.  It's unfortunate because it's the only eyeglass friendly Paradigm.  I would probably recommend skipping the 15mm Paradigm as redundant for most folks.