39 replies to this topic

[BGazing]

I've switched from 12 inch f/5 UC dob to a 355mm f/4.8 sturdy one, that handles heavier EPs with ease and is balanced (with P2). My current set at the moment using with it includes (so this is a total of 1960mm with P2 and f/5.5):

 

40 Paragon (Hbeta only)

30mm UFF

17.3 Delos

13 T6

10 Ethos

8 Ethos

6 Ethos

5 T6 

3.5 T6

 

I left out Pan 24 because it is 'neither here nor there' compared to the others and somehow never feels right. 13T6 is sort a bit of a disruptor in feel of the line. 10-8-6 progression is fantastic. 5 and 3.5 T6 are there 'just in case' the seeing permits.

Two questions.

First, would 30- 20- 13 - 10 progression have more sense in this scope than 30-17-10? This is 65-116-196, so the last jump is huge.

Second, should I go for XWA5, or is T6, long term, sufficient for those fleeting moments of good seeing on planetaries? Too bad I can only use PM2.5 on my 8mm in P2, but that is arleady 600x.

[havasman]

Your ep kit looks great to me. The 40mm doesn't have much value to me but if you use it then there's certainly nothing wrong with that. My kit's similar and I think of it as two sets: one lighter & smaller with the other larger. Yours might be thought of as 24Pan, 13/5/3.5T6 and 30 UFF, 17.3D, 10/8/6E. Either might be all some observers might need and both together should satisfy most anyone's needs.

[SeattleScott]

A 20mm could smooth out the gaps a bit, it just feels like it is harder to find a good 20mm. At ~17 you have your Delos, or Morpheus, or Nikon. Or even Ethos and HW. At ~20mm you could go hyperwide, but the field size would be redundant with the 30mm. And they could be twice as heavy. The 20mm LHD and rebrands is a great performer from what I hear (I like the 14 but don't have the 20). Of course a 22T4 comes to mind, or ES 18/82. 

 

The 13T6 probably has about the same field stop as the 10 Ethos, so kind of redundant other than magnification. 

[BGazing]

A 20mm could smooth out the gaps a bit, it just feels like it is harder to find a good 20mm. At ~17 you have your Delos, or Morpheus, or Nikon. Or even Ethos and HW. At ~20mm you could go hyperwide, but the field size would be redundant with the 30mm. And they could be twice as heavy. The 20mm LHD and rebrands is a great performer from what I hear (I like the 14 but don't have the 20). Of course a 22T4 comes to mind, or ES 18/82. 

 

The 13T6 probably has about the same field stop as the 10 Ethos, so kind of redundant other than magnification. 

Yes, 10E frames everything 13T6 does, so the issue is only one of exit pupil. 

20 XWA-13E-10E has a different magnification progression.

30UFF is basically for filters only if one has 20 hyperwide (Hbeta comes to mind first), I found, though, that 21E I borrowed was, e.g., not as good on Veil, Skull or Crescent as 17E/D, as the magnification and brightness using OIII was 'just right' with the 17mm. 17 also makes a pretty good UHC exit pupil on many targets.

[eblanken]

Hi BGazing & All,

 

What you have seems very useable and pretty well thought out.

My only comment is to compute the spacing as I do when viewing the nice

Pentax XW 68 Deg. AFoV set that I own this way:

40mm, 30mm, 20mm, 14mm, 10mm, 7mm, 5mm, 3.5mm

works out to very nearly 1.4x steps between magnifications,

so to my mind that is a good spacing scheme for me with a tracking mount.

 

Mapping this over to your situation, and first question . . .

that would imply a 40mm, 30mm, 20mm, 13mm, 10mm . . .

but as SeattleScott comments, the choices at 20mm are few . . .

and 17mm choices are more & better . . .

 

I have no help for you on the second question of 5mm . . .

 

Best,

 

Ed

Edited by eblanken, 01 November 2024 - 02:28 PM.

[eblanken]

Hi Again,

 

Your ep kit looks great to me. The 40mm doesn't have much value to me but if you use it then there's certainly nothing wrong with that. My kit's similar and I think of it as two sets: one lighter & smaller with the other larger. Yours might be thought of as 24Pan, 13/5/3.5T6 and 30 UFF, 17.3D, 10/8/6E. Either might be all some observers might need and both together should satisfy most anyone's needs.

 

Dick makes a very good point when he separates the situation into the two sets.

 

Best,

 

Ed

[Jon Isaacs]

 

 

40 Paragon (Hbeta only)

30mm UFF

17.3 Delos

13 T6

10 Ethos

8 Ethos

6 Ethos

5 T6

3.5 T6

 

First:

 

Congratulations on your new scope.

 

Second: My 16 inch has a focal length with a Paracorr 2 of 2070 mm, just about 5% longer than yours.

 

Dick's comment that you have two sets makes a certain sense to me.  What I see is parts of two sets.  The focal lengths all work together as one set but the eyepieces are quite different physically.  The 13mm-10mm-8mm-6mm set is a nice progression but the 13mm T-6 is tiny little eyepiece that has a very different presentation than the 10mm Ethos.  

 

I have both the 13mm Type 6 and the 13 mm Ethos as well as the 13mm XWA.. Crazy but.. You might consider replacing the 13mm Type 6 with the 13mm XWA.  

 

I have the 20mm XWA, you like the 17mm Delos with a filter, so it may make more sense.  For me, the 20mm - 13mm is very workable and for filters, I sometimes remove the Paracorr to get a brighter image. I believe the 13 mm XWA is actually 13.5mm so without the Paracorr it would be equivalent to a 15.5mm eyepiece.  That might be enough.  

 

I also have the 5mm and 3.5mm T-6s. Again these are fine eyepieces but they do not "flow" well with the Ethos.  The step down in AFoV, the much smaller physical size, the shorter eye relief, they just don't work together well for me.  

 

The 4.8mm XWA  and possibly the 3.5 mm XWA fit better for me.  

 

I actually have two sets..

 

30mm UFF or 28mm UWA, 22 mm Panoptics, 16mm Type 5, 13mm, 11mm, 9mm, 7mm, 5mm, 3.5 mm Type 6.. 

 

28mm UWA, 20 mm XWA, 13mm, 10mm, 8 mm Ethos, 7mm, 4.8mm, 3.5mm XWA.  

 

I find mixing the two sets does not work so well, bumping the AFoV and eyepiece size up and down.  

 

I prefer the 28mm UWA to the 30mm UFF.  It has a 12% wider TFoV along with what I perceive as better transmission.  

 

You have a nice collection of quality eyepieces.  Don't rush out and make changes.. 

 

Regarding the 20mm LHD, I have one, I am still feeling it out.  I believe I am seeing some off-axis astigmatism and maybe some EoFB.  It's nice because it's lighter than the 20mm XWA but I prefer the view the 20mm XWA provides.

 

Jon

 

 

[25585]

First:

 

Congratulations on your new scope.

 

Second: My 16 inch has a focal length with a Paracorr 2 of 2070 mm, just about 5% longer than yours.

 

Dick's comment that you have two sets makes a certain sense to me.  What I see is parts of two sets.  The focal lengths all work together as one set but the eyepieces are quite different physically.  The 13mm-10mm-8mm-6mm set is a nice progression but the 13mm T-6 is tiny little eyepiece that has a very different presentation than the 10mm Ethos.  

 

I have both the 13mm Type 6 and the 13 mm Ethos as well as the 13mm XWA.. Crazy but.. You might consider replacing the 13mm Type 6 with the 13mm XWA.  

 

I have the 20mm XWA, you like the 17mm Delos with a filter, so it may make more sense.  For me, the 20mm - 13mm is very workable and for filters, I sometimes remove the Paracorr to get a brighter image. I believe the 13 mm XWA is actually 13.5mm so without the Paracorr it would be equivalent to a 15.5mm eyepiece.  That might be enough.  

 

I also have the 5mm and 3.5mm T-6s. Again these are fine eyepieces but they do not "flow" well with the Ethos.  The step down in AFoV, the much smaller physical size, the shorter eye relief, they just don't work together well for me.  

 

The 4.8mm XWA  and possibly the 3.5 mm XWA fit better for me.  

 

I actually have two sets..

 

30mm UFF or 28mm UWA, 22 mm Panoptics, 16mm Type 5, 13mm, 11mm, 9mm, 7mm, 5mm, 3.5 mm Type 6.. 

 

28mm UWA, 20 mm XWA, 13mm, 10mm, 8 mm Ethos, 7mm, 4.8mm, 3.5mm XWA.  

 

I find mixing the two sets does not work so well, bumping the AFoV and eyepiece size up and down.  

 

I prefer the 28mm UWA to the 30mm UFF.  It has a 12% wider TFoV along with what I perceive as better transmission.  

 

You have a nice collection of quality eyepieces.  Don't rush out and make changes.. 

 

Regarding the 20mm LHD, I have one, I am still feeling it out.  I believe I am seeing some off-axis astigmatism and maybe some EoFB.  It's nice because it's lighter than the 20mm XWA but I prefer the view the 20mm XWA provides.

 

Jon

I have not noticed astigmatism or EOFB in my 20 LHD, using F5 scopes. In fact it gives better views than the 22T4 I had. My experience is edge to edge sharpness and pinpoint stars.

[Jon Isaacs]

I have not noticed astigmatism or EOFB in my 20 LHD, using F5 scopes. In fact it gives better views than the 22T4 I had. My experience is edge to edge sharpness and pinpoint stars.

 

How dark were the skies? Were you using a Paracorr in Newtonians?

 

Were you looking at dim field stars or brighter stars?

 

Jon

Edited by Jon Isaacs, 01 November 2024 - 06:34 PM.

[CeleNoptic]

I have not noticed astigmatism or EOFB in my 20 LHD, using F5 scopes.

 
IIRC, Don Pensack who also has an F/5 Dob describing the LHD's performance stressed he had noticed EOFB. YMMV.

[Mike Q]

 
IIRC, Don Pensack who also has an F/5 Dob describing the LHD's performance stressed he had noticed EOFB. YMMV.

I have not noticed EOFB in my 20mm LHD either.

[Mike Q]

I've switched from 12 inch f/5 UC dob to a 355mm f/4.8 sturdy one, that handles heavier EPs with ease and is balanced (with P2). My current set at the moment using with it includes (so this is a total of 1960mm with P2 and f/5.5):

 

40 Paragon (Hbeta only)

30mm UFF

17.3 Delos

13 T6

10 Ethos

8 Ethos

6 Ethos

5 T6 

3.5 T6

 

I left out Pan 24 because it is 'neither here nor there' compared to the others and somehow never feels right. 13T6 is sort a bit of a disruptor in feel of the line. 10-8-6 progression is fantastic. 5 and 3.5 T6 are there 'just in case' the seeing permits.

Two questions.

First, would 30- 20- 13 - 10 progression have more sense in this scope than 30-17-10? This is 65-116-196, so the last jump is huge.

Second, should I go for XWA5, or is T6, long term, sufficient for those fleeting moments of good seeing on planetaries? Too bad I can only use PM2.5 on my 8mm in P2, but that is arleady 600x.

I would add a 20mm of some variation

[CeleNoptic]

I have not noticed EOFB in my 20mm LHD either.

 
No surprise there. I suspect variation in human vision physiology is responsible for that. Some see, some don't. E.g., Ernest thinks that EOFB is just a figment of impressionable observers . Even though it was documented/pictured well enough in this forum. I clearly see it in the same eyepieces (especially in zooms, but not only) the other folks sensitive to EOFB report it. It's impossible to predict so I'd take all recommendations from others with a big grain of salt. If one never saw it is a good sign that s/he will never see it at all. Otherwise, only firsthand experience with certain eyepiece can help, IMO.

[SeattleScott]

IIRC, Don Pensack who also has an F/5 Dob describing the LHD's performance stressed he had noticed EOFB. YMMV.

Don noted mild EOFB in the 14LHD. Which personally I don’t notice. Don is more sensitive to EOFB than most people.

The 14LHD has outstanding edge correction, but I haven’t tried the 20.

[SeattleScott]

No surprise there. I suspect variation in human vision physiology is responsible for that. Some see, some don't. E.g., Ernest thinks that EOFB is just a figment of impressionable observers . Even though it was documented/pictured well enough in this forum. I clearly see it in the same eyepieces (especially in zooms, but not only) the other folks sensitive to EOFB report it. It's impossible to predict so I'd take all recommendations from others with a big grain of salt. If one never saw it is a good sign that s/he will never see it at all. Otherwise, only firsthand experience with certain eyepiece can help, IMO.

Ernest doesn’t deny it exists, it just doesn’t bother him. For him, and me, it’s low on the list of issues. I suppose if I had an eyepiece with more than mild EOFB, it might bother me. I have avoided ones with a reputation for excessive EOFB,

[25585]

 
IIRC, Don Pensack who also has an F/5 Dob describing the LHD's performance stressed he had noticed EOFB. YMMV.

That was the 14mm.

[25585]

How dark were the skies? Were you using a Paracorr in Newtonians?

 

Were you looking at dim field stars or brighter stars?

 

Jon

No Paracorr, dark sky on Exmoor (no idea Bortle, SQ, colour zone, etc). Lots of sheep though. 

[CeleNoptic]

Ernest doesn’t deny it exists, it just doesn’t bother him.

Nope. He does deny! He just doesn't say about it here. 

[BGazing]

First:

 

Congratulations on your new scope.

 

Second: My 16 inch has a focal length with a Paracorr 2 of 2070 mm, just about 5% longer than yours.

 

Dick's comment that you have two sets makes a certain sense to me.  What I see is parts of two sets.  The focal lengths all work together as one set but the eyepieces are quite different physically.  The 13mm-10mm-8mm-6mm set is a nice progression but the 13mm T-6 is tiny little eyepiece that has a very different presentation than the 10mm Ethos.  

 

I have both the 13mm Type 6 and the 13 mm Ethos as well as the 13mm XWA.. Crazy but.. You might consider replacing the 13mm Type 6 with the 13mm XWA.  

 

I have the 20mm XWA, you like the 17mm Delos with a filter, so it may make more sense.  For me, the 20mm - 13mm is very workable and for filters, I sometimes remove the Paracorr to get a brighter image. I believe the 13 mm XWA is actually 13.5mm so without the Paracorr it would be equivalent to a 15.5mm eyepiece.  That might be enough.  

 

I also have the 5mm and 3.5mm T-6s. Again these are fine eyepieces but they do not "flow" well with the Ethos.  The step down in AFoV, the much smaller physical size, the shorter eye relief, they just don't work together well for me.  

 

The 4.8mm XWA  and possibly the 3.5 mm XWA fit better for me.  

 

I actually have two sets..

 

30mm UFF or 28mm UWA, 22 mm Panoptics, 16mm Type 5, 13mm, 11mm, 9mm, 7mm, 5mm, 3.5 mm Type 6.. 

 

28mm UWA, 20 mm XWA, 13mm, 10mm, 8 mm Ethos, 7mm, 4.8mm, 3.5mm XWA.  

 

I find mixing the two sets does not work so well, bumping the AFoV and eyepiece size up and down.  

 

I prefer the 28mm UWA to the 30mm UFF.  It has a 12% wider TFoV along with what I perceive as better transmission.  

 

You have a nice collection of quality eyepieces.  Don't rush out and make changes.. 

 

Regarding the 20mm LHD, I have one, I am still feeling it out.  I believe I am seeing some off-axis astigmatism and maybe some EoFB.  It's nice because it's lighter than the 20mm XWA but I prefer the view the 20mm XWA provides.

 

Jon

 

 

I would add a 20mm of some variation

Thank you, adding 20 implies a 13 of comparable heft and FOV.

I had to google LHD, is that a clone of T4, or a different eyepiece? Did not find much on it, and looks more expensive than 20 XWA.

[Piero DP]

I've switched from 12 inch f/5 UC dob to a 355mm f/4.8 sturdy one, that handles heavier EPs with ease and is balanced (with P2). My current set at the moment using with it includes (so this is a total of 1960mm with P2 and f/5.5):

40 Paragon (Hbeta only)
30mm UFF
17.3 Delos
13 T6
10 Ethos
8 Ethos
6 Ethos
5 T6
3.5 T6

I left out Pan 24 because it is 'neither here nor there' compared to the others and somehow never feels right. 13T6 is sort a bit of a disruptor in feel of the line. 10-8-6 progression is fantastic. 5 and 3.5 T6 are there 'just in case' the seeing permits.
Two questions.
First, would 30- 20- 13 - 10 progression have more sense in this scope than 30-17-10? This is 65-116-196, so the last jump is huge.
Second, should I go for XWA5, or is T6, long term, sufficient for those fleeting moments of good seeing on planetaries? Too bad I can only use PM2.5 on my 8mm in P2, but that is arleady 600x.

What kind of objects do you observe the most? A bit of everything, mostly planets and moon, mostly small DSOs, mostly extended nebulae?

Your eyepiece collection covers all the focal lengths you need and possibly more to me.

Said this those eyepieces have different ergonomics as it has been pointed out. This might be an issue or not for you. For instance the 30 uff and 17 Delos fit well together. The Naglers T6 and 24 Pan fit well together. The ethos also fit well together. You seem to like the ethos so maybe you might want to end up with a set of XWAs.
So in terms of progression, personally I think you are well covered. To me the question is what do you think it does not work or seem quite right? E.g. ergonomics, need for more FOV at low/high power, parfocal set, balancing, different eye relief, different presentation, ..?

I would not rush to change your set as it is a good one already. Rather I would use it with your new telescope for a while until at least you get more insights about what you enjoy using the most in terms of targets and eyepiece type.
It is also worth remembering that for some people, having a set of different eyepiece types works very well, so again, if I were you I would take time to figure out what works best for you.

[Piero DP]

By the way, with my 16" F4 + PC2 I use (13-9-7 XWAs) or (Docter+8-6 Delos) most of the time. These trios are part of two separate sets. The 13 XWA and Docter are medium / low powers in this telescope (~150x). In your telescope they yield about 2.5mm exit pupil and that can find good use on a few targets as well as finder ep when spotting small and dim targets.
You already have a 13mm focal length although the Nagler 13mm T6 feels like a dwarf between two giants (Delos 17 and ethos 10). I'm a bit puzzled on how the 17mm Delos is used next to the 13mm nagler T6 and the ethos 10mm. Do you swap them mainly due to different exit pupils?

If you have other telescopes (e.g. a small refractor), you could end up with a XWAS set for the dob and a small NT6 + 24 Pan set for the refractor.

[Mike Q]

Thank you, adding 20 implies a 13 of comparable heft and FOV.

I had to google LHD, is that a clone of T4, or a different eyepiece? Did not find much on it, and looks more expensive than 20 XWA.

https://agenaastro.c...-e20w-cu01.html

 

There is a link for one version of it.  My verson is Orion branded.  I think it is also branded as Founder Optics and FLO in England has the under their house name.  I don't  believe it's a clone of anything but it does seem to give excellent images and according to some reviews competes very nicely against the T4

Edited by Mike Q, 02 November 2024 - 05:31 AM.

[SeattleScott]

Much newer design than the T4. Better edge correction than T4 from what I understand.

Should not be significantly more expensive than a 20XWA, although probably about the same price.

[BGazing]

What kind of objects do you observe the most? A bit of everything, mostly planets and moon, mostly small DSOs, mostly extended nebulae?

Your eyepiece collection covers all the focal lengths you need and possibly more to me.

Said this those eyepieces have different ergonomics as it has been pointed out. This might be an issue or not for you. For instance the 30 uff and 17 Delos fit well together. The Naglers T6 and 24 Pan fit well together. The ethos also fit well together. You seem to like the ethos so maybe you might want to end up with a set of XWAs.
So in terms of progression, personally I think you are well covered. To me the question is what do you think it does not work or seem quite right? E.g. ergonomics, need for more FOV at low/high power, parfocal set, balancing, different eye relief, different presentation, ..?

I would not rush to change your set as it is a good one already. Rather I would use it with your new telescope for a while until at least you get more insights about what you enjoy using the most in terms of targets and eyepiece type.
It is also worth remembering that for some people, having a set of different eyepiece types works very well, so again, if I were you I would take time to figure out what works best for you.

 

 

By the way, with my 16" F4 + PC2 I use (13-9-7 XWAs) or (Docter+8-6 Delos) most of the time. These trios are part of two separate sets. The 13 XWA and Docter are medium / low powers in this telescope (~150x). In your telescope they yield about 2.5mm exit pupil and that can find good use on a few targets as well as finder ep when spotting small and dim targets.
You already have a 13mm focal length although the Nagler 13mm T6 feels like a dwarf between two giants (Delos 17 and ethos 10). I'm a bit puzzled on how the 17mm Delos is used next to the 13mm nagler T6 and the ethos 10mm. Do you swap them mainly due to different exit pupils?

If you have other telescopes (e.g. a small refractor), you could end up with a XWAS set for the dob and a small NT6 + 24 Pan set for the refractor.

You're absolutely correct, no rush is in order, and there will be some evaluation going on first. I ended up with two distinct sets because of the different scopes, and you are right, 24P-T6 13 and down to 3.5 is a great Tak 100 lineup, indeed.

I did not care much for Ethoi, but looking through 6mm in my Alkaid changed my mind. Orthoscopic 100 degrees. Makes sense in a dob only, really, can't clean up that field in a SCT.

I ended up with this eclectic bunch because of the different scopes, but swapping them out is indeed because of the exit pupil. My equipment path was erratic, unlike yours (I remember your posts)

[Piero DP]

Thank you
To be fair though, I tried way too many eyepieces than what I would have imagined before starting off this astronomy journey.. it's just that if an eyepiece does not work for me, I tend to sell it. In some cases, this behaviour has made me buying the same eyepiece more than once though!
Coming back to progressions, my main interest are smallish galaxies, PNs, globs and small open clusters. I find that the range of 2.5-1.5mm exit pupils is used most of the time. I consider that range as a guideline rather than a strict range to adhere to. To add to that I use 1 low power ep for larger targets. This is not necessarily used as my finder eyepiece, as many times I use a low/medium power ep for this purpose instead. Then I use a couple of high power eyepieces (4.7-3.6mm APM XWAs or Badder VIP Barlow of 8-6mm Delos) for high powers.

With my 4" refractor I use the 30mm APM UFF, Docter and VIP(Zeiss zoom). The latter combo is phenomenal on-axis but shows too much astigmatism off-axis at f4 and and is not very handy to use with the HC-2 focuser of my f6 dob.
All these eyepieces are or converted to 2" as I prefer this barrel size when handling medium to large EPs.
My small eyepieces are used with my TV-60 (primarily) or for grab and go observations. They might get more used in the future if I decide to create an astronomy club in my small village or when my f6 dob is converted to F5.

Yeah, eyepiece journeys can be complex..