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Help me choose: 13 LVW or 14 Delos?

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#1 FoxTrot

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Posted 13 December 2012 - 05:22 AM

Dear CN members. I have a 13mm LVW (for my NP127is), and whilst its a nice eyepiece in my scope, I've always felt that it does show noticeable distortion both at the edge and across the field in general (which may be related to the NP127is being such a fast scope).

Because the 10% discount TV sale is still on, I went to my local astro shop today, and briefly compared the 13mm LVW to a 14mm Delos, albeit for daytime viewing only. The Delos seemed to give a brighter image with better edge performance, and the LVW also seemed to have more chromatic aberration. The Delos, however seemed more fussy with eye position (blackouts) - but I realise that its very hard to know how it will feel with astronomical use, because your eyes behave so differently with night vs. daytime viewing.

Which do you reckon is better, the 13mm LVW or Delos 14mm...? Fox

#2 Scanning4Comets

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Posted 13 December 2012 - 06:03 AM

The 14mm Delos will be a better eyepiece with the newer glass and newer coatings no doubt! I owned a 6mm Delos and it was no slouch!

I have a 13mm LVW and I see no distortion near the edges in my 10" F/4.7 reflector. It's also very comfy to look through, but if I had the choice, I'd grab the 14mm Delos hands down!

Cheers,

#3 george golitzin

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Posted 13 December 2012 - 05:28 PM

I've wanted to try the lvw series for some time now, but never have, so this is an interesting thread...

You mentioned color in the LVW. I see a bit of lateral color in the 14 Delos, compared to my XWs, which only show a purple fringe right at the edge of field. The delos starts to color the limb of jupiter halfway out from center. As for blackouts, you get used to the eyepiece very quickly once you have the eyecup properly adjusted...but I have heard that the lvw is exceptionally comfortable in that regard.

The other qualities of the delos are all wonderful: exceptionally flat, very tight star images across the field, good baffling, and I suspect about as good as it gets for transmission of low contrast faint objects. Also, despite its color on Jupiter, I find it makes a great planetary eyepiece when coupled with a barlow.

I'll be interested in hearing from the lvw owners, and also from any delos types regarding the color issue.

-geo

#4 maroubra_boy

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Posted 14 December 2012 - 01:03 AM

Foxie, get the Delos & I'll take the 13mm Vixen off your hands :jump:

Alex (in Oz too)

#5 Scanning4Comets

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Posted 14 December 2012 - 08:09 AM

Yep,

The 13mm Vixen LVW is no slouch. I compare it to my 10mm XW as far as sharpness goes, the LVW's are incredible eyepieces.
I use a barlow on the 13mm LVW for Jupiter and there is a tiny bit of lateral color when it gets near the edge, but I always re-center the target anyways. I'm going to grab the 17mm LVW when a good friend of mine gets the 17mm Delos and sells me his 17mm LVW! :whistle:

#6 BillP

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Posted 14 December 2012 - 08:48 AM

Which do you reckon is better, the 13mm LVW or Delos 14mm...? Fox


I don't have a lot of experience with the Delos except for some brief uses. The Orion Stratus, Baader Hyperion, and Vixen LVW though I have owned and used a lot. I agree that while they are great eyepieces, their off-axis is certainly not near perfect. The 5mm and 8mm are the best, but then from there into the longer focal lengths it creeps in more and more. The 17mm I did not like at all. 13mm I found tolerable.

At any rate, the Delos, given TVs attention to the off-axis, should give you a much improved off-axis. No doubt also that the image will be brighter given the many reports to this point and of course its use of the newest coatings.

On the eye positioning thing not sure. The LVWs and similar are fairly comfortable and stable. With the Delos, am sure that a properly poistioned eye guard will substantially fix any blackout issues from the long eye relief. Key to positioning it correctly, per TV, is to extend it all the way, then observe through it, and lower it while observing until you can just see the entire FOV, then lock. This gets you the optimum positioning.

#7 FoxTrot

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Posted 14 December 2012 - 09:53 AM

Thank you for your responses. I think its going to be a case of probably acquiring the Delos 14mm and doing an A-B comparison with my own eyes and scope. Thereafter, I'll see which one I want to keep. One thing I really like about the LVW's is that they are 1.25/2.00 inch dual barrel across the range. It's a surprisingly useful feature because the 13mm LVW sits right in the middle of my Pentax XW 7mm (1.25inch) and Panoptic 27mm (2.00 inch). Fox

#8 Scanning4Comets

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Posted 14 December 2012 - 10:30 AM

I don't have a lot of experience with the Delos except for some brief uses. The Orion Stratus, Baader Hyperion, and Vixen LVW though I have owned and used a lot. I agree that while they are great eyepieces, their off-axis is certainly not near perfect. The 5mm and 8mm are the best, but then from there into the longer focal lengths it creeps in more and more. The 17mm I did not like at all. 13mm I found tolerable.


Not even close...Maybe my samples are different than what others have seen? I dunno.

Many people prefer the longer focal length Vixen LVW's over the Pentax XW's and XL's because of the field curvature. Especially in the 14mm XW ~ The field curvature in the 14mm XW will make you feel like you were in warp speed going through the speed of light. The 13mm Vixen LVW in my 10" F/4.7 shows stars almost flat right to the edges....The same goes for the 22mm Vixen LVW ~ It has incredible correction. The 20mm Pentax XW shows some field curvature as well. In this regard, the 22mm Vixen LVW beats the 20mm XW in edge correction 100%.

If I had the choice to get the 20mm XW or the 22mm LVW, I would take the 22mm LVW in a heartbeat.

Cheers,

#9 BillP

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Posted 14 December 2012 - 03:27 PM

Indeed interesting. The 17 LVW I purchased new and it was the last one I got...and sold. Off-axis was not controlled commensurate with its price level at all. Horrible IMO. My 20XW was far superior to what the 17 LVW was showing in my APO. The 13mm was not superior to my 14XW -- which btw shows very very little FC in my TSA-102.

#10 Starman81

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Posted 14 December 2012 - 03:51 PM

I don't have a lot of experience with the Delos except for some brief uses. The Orion Stratus, Baader Hyperion, and Vixen LVW though I have owned and used a lot. I agree that while they are great eyepieces, their off-axis is certainly not near perfect. The 5mm and 8mm are the best, but then from there into the longer focal lengths it creeps in more and more. The 17mm I did not like at all. 13mm I found tolerable.


Not even close...Maybe my samples are different than what others have seen? I dunno.

Many people prefer the longer focal length Vixen LVW's over the Pentax XW's and XL's because of the field curvature. Especially in the 14mm XW ~ The field curvature in the 14mm XW will make you feel like you were in warp speed going through the speed of light. The 13mm Vixen LVW in my 10" F/4.7 shows stars almost flat right to the edges....The same goes for the 22mm Vixen LVW ~ It has incredible correction. The 20mm Pentax XW shows some field curvature as well. In this regard, the 22mm Vixen LVW beats the 20mm XW in edge correction 100%.

If I had the choice to get the 20mm XW or the 22mm LVW, I would take the 22mm LVW in a heartbeat.

Cheers,


I've been using the XW 20 a lot recently and keeping a very watchful eye out for field curvature. I've been comparing the 20 to an LVW 22 I own. Observing with the XT8i dob (f/6)...

With the XW 20, FC is present, but can be accomodated quite easily if you focus stars about 2/3 of the way out to the edge. My eyes being only 31 years old helps. The immersiveness of 70* vs 65* is notable. The XW 20 has a slight bit more ER than the LVW 22, as I frequently touch my glasses onto the rubber eyecup (slightly) of the 22 when trying to take in the entire view--something that does not happen with the XW 20. With the scope on the double cluster and 3 different observers, 1 liked the XW better (myself), 1 liked the LVW and the other was undecided. With the sword of Orion, some of the bright stars at the edge of field in the LVW 22 showed a violet halo, while XW 20 did not. However, LVW 22 had a flatter field and if the XW 20 was not focused precisely to the match one's accomodation, you would see the FC.

So I don't think that either one is perfect but they are both pretty darn good and you cannot go wrong with either one if you have the right expectations.

#11 Scanning4Comets

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Posted 14 December 2012 - 06:24 PM

Indeed interesting. The 17 LVW I purchased new and it was the last one I got...and sold. Off-axis was not controlled commensurate with its price level at all. Horrible IMO. My 20XW was far superior to what the 17 LVW was showing in my APO. The 13mm was not superior to my 14XW -- which btw shows very very little FC in my TSA-102.

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I was not saying that the 22mm LVW was superior transmission wise, I only said edge wise. The same goes for the 13mm LVW. The 14mm and 20mm XW's show considerable FC, whereas, the 13mm and 22mm LVW's have none. Maybe you have sellers remorse. :lol:

Cheers,

#12 GeneT

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Posted 14 December 2012 - 07:24 PM

Thank you for your responses. I think its going to be a case of probably acquiring the Delos 14mm and doing an A-B comparison with my own eyes and scope


I will be very interested in your report.






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