A summers night with a new eyepiece

[John]

I don't think there is much difference in light transmission between an ortho and the top quality multi-element extra wide angle eyepiece - maybe a % or two. This is not going to result in a difference that can be detected visually I believe - a 10% difference in transmission equates to 0.1 of a magnitude difference which is apparently the smallest difference that experienced variable star observers can detect.

There maybe other factors at work though ?

 

 

 

 

[Littleguy80]

Perhaps contrast is the term I’m looking for rather than transmission, John. The performance difference between between the orthos and widefields is quite noticeable to my eyes. Do you find your Delos more effective than Ethos when looking at the fainter objects?

[John]

3 minutes ago, Littleguy80 said:

Perhaps contrast is the term I’m looking for rather than transmission, John. The performance difference between between the orthos and widefields is quite noticeable to my eyes. Do you find your Delos more effective than Ethos when looking at the fainter objects?

Not really Neil.

I used to have a number of good quality ortho's which I felt would compliment my wide fields but after many comparisons I came to the conclusion that the wide fields showed the full range of astro targets just as well as the orthos did (to my eye anyway) and I was not too keen on the eye relief, small eye lenese and narrow fields of the orthos so I let them go to new homes. I do still have a Fujiyama 4mm HD ortho but very rarely use it now. 

The nearest I have to an ortho now is probably the Nagler 2-4mm zoom.

"Your mileage may vary" as we should always say on these matters

 

[Stardaze]

8 hours ago, Littleguy80 said:

The 20mm APM is superb. A very well respected member on here puts it right up there with the Ethos 21mm. The Morpheus have a good reputation. In those focal lengths I’d be going for Delos or Pentax XW personally. Do you have an existing eyepiece in the 9mm range? If so, have a think about the objects you like to observe with it. Use SkySafari or Stellarium to see how the FOV compares using those eyepieces. That’s what helped me to decide to go for the 10mm Delos. I’ve had the 9mm Lunt a couple of years now. Lovely eyepiece but when I want to see the fainter targets, I always use my 9mm BGO. 42 degree AFOV but great transmission and sharpness. I wouldn’t have seen Stephan’s Quintent without it. The Delos should be much closer to the BGO but with over 70 degrees AFOV. It’s really a case of choosing whether it’s sharpness/transmission you want or an extra wide FOV. All down to personal preference and wallet size  

I think sharpness and transmission is definitely more beneficial over absolute FOV for me at higher magnifications, which is what got me thinking more about where to go. I haven't anything in-between 13mm and 6.7mm at the moment and often find myself needing something here, so I do need to plug the gap. I find myself drilling down to more detailed objects at those magnifications and mostly DSO. Thanks for your input. 

[Stardaze]

8 hours ago, John said:

Not really Neil.

I used to have a number of good quality ortho's which I felt would compliment my wide fields but after many comparisons I came to the conclusion that the wide fields showed the full range of astro targets just as well as the orthos did (to my eye anyway) and I was not too keen on the eye relief, small eye lenese and narrow fields of the orthos so I let them go to new homes. I do still have a Fujiyama 4mm HD ortho but very rarely use it now. 

The nearest I have to an ortho now is probably the Nagler 2-4mm zoom.

"Your mileage may vary" as we should always say on these matters

 

What's your take on the 150x and above magnifications John? I know that you have the best of both worlds, but use the Ethos 8mm and 4.7mm presumably. What comparisons can you make against Delos at those magnifications? Would you miss the additional FOV in the dob? 

[John]

8 hours ago, Stardaze said:

..... Would you miss the additional FOV in the dob? 

Yes 

[Stardaze]

35 minutes ago, John said:

Yes 

I kinda knew you’d say that. It’s not a comparative view I guess, given that you have got the very best 100 degree EP’s available. 
Swaying towards Delos. There’s something about the Pentax that I don’t like, and sadly, it’s probably a brand thing given my photography background. I know I shouldn’t, but..

[Littleguy80]

34 minutes ago, Stardaze said:

I kinda knew you’d say that. It’s not a comparative view I guess, given that you have got the very best 100 degree EP’s available. 
Swaying towards Delos. There’s something about the Pentax that I don’t like, and sadly, it’s probably a brand thing given my photography background. I know I shouldn’t, but..

There’s some great detailed comparison reviews on the Delos and XW’s at various focal lengths by @alan potts on here. There was very little to pick between them. I think the XW were often given a very marginal win but ultimately you should be very happy with either of these. 

[John]

I like Pentax for photography but that goes back to 35mm days !.

It was a Pentax XW 10m that first showed me that there were (slightly) better eyepieces around than Tele Vue Naglers. I had a set of Type 6 Naglers back then and FLO loaned me a Pentax XW 10mm to compare with the 9mm T6 Nagler. I found myself slightly preferring the XW, rather to my surprise and it was a more comfortable eyepiece to observe with.

I still hankered after ultra-wide views though and then the Ethos came along. Sharper, whiter views than Naglers and 100 degrees as well. Right up my street

I just have the one Nagler now - the mighty 31mm.

Delos are great eyepieces and so are XW's. So are Ethos and so are Morpheus and a number of others. Eyepiece choice is very personal though and stuff like ergonomics etc come into the decision at this level more than pure optical performance I reckon.

 

 

 

[alan potts]

13 hours ago, Littleguy80 said:

There’s some great detailed comparison reviews on the Delos and XW’s at various focal lengths by @alan potts on here. There was very little to pick between them. I think the XW were often given a very marginal win but ultimately you should be very happy with either of these. 

Indeed, being a TeleVue snob I kept the Delos or whatever it was against but on the 5mm and 3.5mm the XW just edged it but it really was so so close. I tried to be honest. I really must try and push myself away from the Cameras and towards the eyepieces, I have a massive amount of money tied up in the scopes and the eyepieces. The trouble is out here there is not a massive market or many people to buy high end gear, yes the eyepieces I could easily off load to the UK before the end of the year, but 5 scopes not being used is another question and not really  shipable items.

Alan

[alan potts]

13 hours ago, John said:

I like Pentax for photography but that goes back to 35mm days !.

It was a Pentax XW 10m that first showed me that there were (slightly) better eyepieces around than Tele Vue Naglers. I had a set of Type 6 Naglers back then and FLO loaned me a Pentax XW 10mm to compare with the 9mm T6 Nagler. I found myself slightly preferring the XW, rather to my surprise and it was a more comfortable eyepiece to observe with.

I still hankered after ultra-wide views though and then the Ethos came along. Sharper, whiter views than Naglers and 100 degrees as well. Right up my street

I just have the one Nagler now - the mighty 31mm.

Delos are great eyepieces and so are XW's. So are Ethos and so are Morpheus and a number of others. Eyepiece choice is very personal though and stuff like ergonomics etc come into the decision at this level more than pure optical performance I reckon.

 

 

 

I always thought the XW was a better eyepiece than the Nagler though for me they are not really the same and I like to try to compare apples with apples, the Delos range and XW's are pretty much the same FOV. Like you John I too only have the 31mm Nagler. I kept almost all my Ethos'sss  purely for the 18 inch Dob, which for me is where they shine but you need a paracorr at F4.3 with that range, I off loaded the 3.7mm but have the rest. It is much the same with the 41mm which only ever got light in the LX 200, which has not been used now for 2 years. A lot of it came down to my prostate problem when I was strongly advised not to go out in the cold, as a result I stopped using the scopes across the period Nov 2018 until I was operated on in late Oct last year. Even though I am now fine in most departments I have not pushed myself to get the scopes out, maybe Jupiter will be calling me. Weather has been most un-Bulgarian too.

Alan

[Stardaze]

Had a read of a couple of your threads @alan potts so thanks for contributing those. I think I do hanker after a black and green addition to my collection. Planning the 'less is more' approach with maybe 5-6 EP's to cover me throughout, eventually and pay for keepers rather than trading up every now and again. I'll try stretch to a 10mm Delos next month and save a bit for an 8mm. If I could add a 2x power mate to those two, I don't think I'd need longer than the 8. That said, I'd maybe like to buy a 10mm and 6mm Ortho for a bit of fun. They're certainly not going to stretch the wallet too much. 

[alan potts]

11 minutes ago, Stardaze said:

Had a read of a couple of your threads @alan potts so thanks for contributing those. I think I do hanker after a black and green addition to my collection. Planning the 'less is more' approach with maybe 5-6 EP's to cover me throughout, eventually and pay for keepers rather than trading up every now and again. I'll try stretch to a 10mm Delos next month and save a bit for an 8mm. If I could add a 2x power mate to those two, I don't think I'd need longer than the 8. That said, I'd maybe like to buy a 10mm and 6mm Ortho for a bit of fun. They're certainly not going to stretch the wallet too much. 

Thank-you for those kind words. Having had most of the TV range apart from De-lite I don't feel you will be disappointed no matter which you go for. Rather like you suggest I bought almost all the Meade 5000 ranges at some point, though they are good eyepieces I find in faster scopes they get found out at the edges, TV do not.

Alan

[Stardaze]

I might trade a camera lens in to downgrade to the lesser model, free up some cash for certainly a Delos 10mm and possibly an 8mm too. 🤔 

Edited July 25, 2020 by Stardaze

[alan potts]

21 hours ago, Stardaze said:

I might trade a camera lens in to downgrade to the lesser model, free up some cash for certainly a Delos 10mm and possibly an 8mm too. 🤔 

The 6mm and 10mm were the first I bought, cracking eyepieces, then the cracking came into play in a manner that still hurts. One night the scope fell off the mount and the 6mm did indeed crack.

Alan

[Littleguy80]

1 hour ago, alan potts said:

The 6mm and 10mm were the first I bought, cracking eyepieces, then the cracking came into play in a manner that still hurts. One night the scope fell off the mount and the 6mm did indeed crack.

Alan

I have a real fear of something like this happening. What a nightmare. I guess the only option is bin it and buy another 

[alan potts]

1 minute ago, Littleguy80 said:

I have a real fear of something like this happening. What a nightmare. I guess the only option is bin it and buy another 

I did just that though a couple of month later, I was lucky to pick one up S/H, I got those two in the first week of launch. Really good range of eyepieces, I had all of them but now only the two shortest, I kept my Ethos range where so many doubled up. I mad an effort to say I would get the Dob out last night, what happened, rained hard. life for you.

Alan