Pentax XW tone

[jetstream]

I'm wondering what Pentax XW users think about the tone of these eyepieces? ie Rich, neutral or cool.

Also, it would be interesting to hear about the tone of any other eyepieces of the same class ( low scatter,sharp, planetary) . Any AFOV as long as the low scatter, sharp requirement is met.

[Don Pensack]

24 minutes ago, jetstream said:

I'm wondering what Pentax XW users think about the tone of these eyepieces? ie Rich, neutral or cool.

Also, it would be interesting to hear about the tone of any other eyepieces of the same class ( low scatter,sharp, planetary) . Any AFOV as long as the low scatter, sharp requirement is met.

Many people think the XWs have a "cool" tone that tends to suppress the warmer colors.

I've compared them directly in a triplet apo that lacks CA by using them to look at an arctic white building, where you can look directly at the building, then in the eyepiece, then directly at the building.

Many, many eyepieces change the tone of the white, and very few see the white as the pure arctic white it is.

There is a red wind sock on the top of the building that appears orange or even grey in some eyepieces because their responses fall off in the longer wavelengths.

All of these color rendition issues tend to disappear at night except on the Moon or planets, but some show up when looking at carbon stars or red giants.

 

Anyway, the XWs have a strong yellowish tone to them when looking at that white building.  I am mystified some see the view as "cool".

The red windsock is still red, but a bit less intensely red than the naked eye, which is consistent with the measured steep drop-off they have above 650nm.

 

The TeleVue Delos, on the other hand, had a better color rendition, with the building still arctic white and the red windsock still the same as the naked eye.

This can be seen at night when looking at Carbon stars and red giants.  I think it may be the lack of fall-off in the red end of the spectrum that makes some observers

describe them as "warm" in tone.  Maybe that is true in comparison with the XWs, but I found them more neutral in my daylight test.

 

So if you are looking for a 70° field eyepiece for planetary use, I think you would find planetary colors less suppressed by the Delos.

You will find differing opinions from different observers.  I think that is because color vision sensitivities in the violet and red vary all over the place among observers.

 

However, you do have to pay attention to whether the diagonal is a mirror or prism, how low in the atmosphere you view, and chromatic issues in the scope.

You have a reflector scope, which is free of chromatic aberration.  Are you planning to get a new scope?  Because these eyepieces are expensive and might be hard to justify

in your current scope.  I guess I should ask what it is about your current eyepieces that has you seeking out others.  Because if they are not sharp on axis, it might not be the eyepiece at fault,

but the cooling of the optics, or collimation, or simply the seeing conditions.  What is it that you don't like in them?

Edited February 27, 2023 by Don Pensack

[jetstream]

42 minutes ago, Don Pensack said:

Are you planning to get a new scope?

 

42 minutes ago, Don Pensack said:

What is it that you don't like in them?

Hi Don, I have a TSA120 that I'm playing around with and a buddy has a new 140mm. We're going to do a bit of comparison on the planets and moon over time and would like to try a couple of different eyepieces, tone wise. We both have the Baader/Zeiss prism but are going to grab the Baader BBHS dielectric as well.

I have Delos, Leica zoom, Zeiss zoom, Fuji orthos and the Docter. All used with the VIP at times. I like them all.

Your test results are very interesting, actually excellent-- I'm going to test my EP's on the snow across the bay now and will put a red cone over there, about 1km away.

What I'm curious about is the presentation of colour in the two scopes , on Jupiter in particular and the effect of eyepiece tone ( or as you describe in your test) and also the prism vs the mirror diag.

Yes I consider the Delos "warm"  as well and interestingly the Zeiss zoom as cool, but with a hint of yellow looking at the snow covered ice.

What is your thought about the colour correction of the TSA 120 in the red, green blue?

How about the new SVx140mm?

Btw, yes I still have the 15" and 24" dobs.

Gerry

 

[Littleguy80]

I have the Pentax XW 5mm and that is cool to my eye. Certainly when compared to the 10mm Delos or Docter with VIP Barlow (with extensions to put it at roughly equivilent to a 7mm eyepiece). The comparitve coolness of the XW applies to both my Dob and Frac. My best planetary views have probably been with a 7mm Meade Research Grade Ortho. Very sharp and more neutral on colour rendition from memory.

[Alan White]

Interesting question.

I consider my XW's 10,7 and 5 more neutral in colour tone, 
My Baader Morpheus 12.5 I consider cooler.

Clearly we all have varying degree of colour perception and I am sure age is in play here too.
When I discuss colour at home, my dearest points out that I see a lot of Green as a Blue tone.
I must point out that traffic lights are very much Red, Amber and Green in my perception!
 

[Sunshine]

Interesting, I have four XW's and I have always noticed when specifically trying to judge colour tone compared to my Morpheus that the XW's fall somewhere in the middle between cool and warm. Imagine having a slider where you can increase and decrease color temperature on an image where centre is neutral. If you were to slide the slider a couple of notches, just a couple towards the warm, that's where I find the XO's sit. Having said that, I would imagine that there are more variables involved than just the eyepiece. I'm inclined to think it may be different in a different telescope as one may consider the diagonal may or may not play a part on how colour tone is perceived? not sure.

Edited February 27, 2023 by Sunshine

[globular]

I use mine in hushed tones, so as not to disturb my neighbours.

They are relatively heavy, as eyepieces go, so they do tone your muscles in use.

I'm so sorry for lowering the tone...  I'll tone it down by going and standing over there in the, slightly cool, warm corner ..... 🧍

[John]

I've tended to feel that the XW's are neutral in tone. Rather similar to the Ethos, for me.

I have one Delos (14mm) but can't see a strong difference in tone between it and my XW's. I don't think that I am particularly sensitive to tones though, not even particularly noticing the much talked about tones in the Radians and TV plossls when I used to own those.

I would have thought that the telescope optics must make an impact. Some refractors are known to be corrected towards one part of the spectrum or another. That has got to affect the tone of the image seen at the eyepiece I would have thought, as has the diagonal being used plus the observers eye sensitivity. So many variables !

[Mr Spock]

When I compared my 10mm eyepieces (neither of which I have any more), the NLV was neutral but the Radian was distinctly yellow/brown.

[dweller25]

I have the 5 and 7mm XW and on the planets they appear neutral to me.

[jetstream]

5 minutes ago, dweller25 said:

I have the 5 and 7mm XW and on the planets they appear neutral to me.

David are there any you consider to be warm? or rich in colour?

[Don Pensack]

11 minutes ago, dweller25 said:

I have the 5 and 7mm XW and on the planets they appear neutral to me.

When looking at planets, how could you tell what is neutral, warm, or cool except by comparison with other eyepieces?

[jetstream]

@Don Pensack would the TSA120 and the SVX140 be good platforms to use re:CA? For tone testing EP's using a mirror diag of course.

[Don Pensack]

3 hours ago, jetstream said:

 

Hi Don, I have a TSA120 that I'm playing around with and a buddy has a new 140mm. We're going to do a bit of comparison on the planets and moon over time and would like to try a couple of different eyepieces, tone wise. We both have the Baader/Zeiss prism but are going to grab the Baader BBHS dielectric as well.

I have Delos, Leica zoom, Zeiss zoom, Fuji orthos and the Docter. All used with the VIP at times. I like them all.

Your test results are very interesting, actually excellent-- I'm going to test my EP's on the snow across the bay now and will put a red cone over there, about 1km away.

What I'm curious about is the presentation of colour in the two scopes , on Jupiter in particular and the effect of eyepiece tone ( or as you describe in your test) and also the prism vs the mirror diag.

Yes I consider the Delos "warm"  as well and interestingly the Zeiss zoom as cool, but with a hint of yellow looking at the snow covered ice.

What is your thought about the colour correction of the TSA 120 in the red, green blue?

How about the new SVx140mm?

Btw, yes I still have the 15" and 24" dobs.

Gerry

 

It's been 5 years since I saw a refractor at my observing sites that didn't have a camera attached.

And Takahashis seem as rare as hen's teeth here.  I see AstroPhysics, TEC, and a veritable see of Chinese and Taiwanese refractors.

But it's been many years since I actually looked through a Takahashi refractor, and my memory of any tonality is gone.

I've never seen an SV140, but if I did, I guarantee it would have a camera attached.

So what you find in your comparison will be equal to anyone's opinion.

 

Though I am certain there are many many refractors being used visually in backyards and on patios, those observers do not seem to bring them to my dark sites.

I am in that category, too, because when I travel to a dark site, I take my 12.5", not the 4" apo.  Most of my friends wouldn't even know I had a 4" refractor, as they've probably

never seen it.

 

[Captain Scarlet]

20 minutes ago, Don Pensack said:

… I've never seen an SV140, but if I did, I guarantee it would have a camera attached. …

If you ever happen by SW Ireland Don be sure to let me know and to drop by Baltimore, County Cork. You can have a look through my SV140, which will only very rarely have a camera attached, and would be a DSLR. Likely you’ll only be looking at clouds though, though they will be SQM21.8 clouds! 😀

Magnus

[globular]

I have a few XWs (7,10,16.5,40).

Mostly I'd describe stuff as in black and white.  This is not a negative - just that there is not a lot of colour out there in the dark. Actually it's a positive... I prefer stars to be white rather than yellow (on the whole).

But then there are lots of things that do have colour.  I never tire of looking at Neptune and being overjoyed by the blue.  I spend lots of time on globulars deciding if it has a yellowey core, or bluey, or white, or violet? surely not!  I'm sure that nebula has a green tinge and that one is red.  Comparing the colour difference of doubles' companions. And my wife and I play endless games of coming up with colours of the bands on Jupiter... brunette, cinnamon, walnut, buff, fawn, .... anything but brown, reddy brown, creamy brown and cream.  Picking out slight colour variations on Mars surface is also a nice game to play - and vital to produce a sketch that goes some way to represent what I'm seeing.  Ok so mostly stuff isn't black and white.

My XWs do a good job in giving me nice sharp views with good colours.  But I have no idea if the colours are 'true' or 'cool' or 'warm'.  I'm just glad they are there because they make my observing more fun than if they weren't. 

I know that's no help... but it's my two penn'orth.  I'll go back to my corner 🤩 

Edited February 28, 2023 by globular
typo

[globular]

29 minutes ago, Captain Scarlet said:

If you ever happen by SW Ireland Don be sure to let me know and to drop by Baltimore, County Cork. You can have a look through my SV140, which will only very rarely have a camera attached, and would be a DSLR. Likely you’ll only be looking at clouds though, though they will be SQM21.8 clouds! 😀

Magnus

Nice to see you are still gushing all over the forum, Magnus 

[jetstream]

20 minutes ago, globular said:

know that's no help...

Actually it is help... and thanks, Gerry

[markse68]

I haven’t used my XWs for a while as i’ve been enjoying my light weight pseudo astroplans  but I always thought they were very neutral with no real tone as such but with saturated colour when it’s there. They’re definitely not warm like my old Tal plossls and likewise not cold like the BCO 10mm that was quite a shock to me when i first got it- its sharpness made up for it though. I don’t have any other expensive eps to compare though

Mark

[IB20]

All I can say is I find the XWs 3.5-10, warmer in tone in comparison to the TOEs. I find the colour transmission of them really pleasing, particularly on Jupiter. I see the GRS as light coral in colour through the XWs in my 3” Tak and 8” dob. 

[dweller25]

16 hours ago, jetstream said:

David are there any you consider to be warm? or rich in colour?

Televue’s

[dweller25]

16 hours ago, Don Pensack said:

When looking at planets, how could you tell what is neutral, warm, or cool except by comparison with other eyepieces?

By memory - so not scientific…..

Televue’s look warm.

I have a 12.5mm KK Ortho that looks cool.

I have never experimented with observing a pure white wall or snow and to be honest it is what it is and does not bother me 🙂👍

[Captain Scarlet]

Is this not a tailor-made project for those of us who do spectroscopy? @andrew s et al? 

[Don Pensack]

Or a spectrophotometer, like the type that measure the responses of filters.

Here are some graphs once on the web for Pentax transmission curves:

https://web.archive.org/web/20141231092400/http://pentaxplus.jp/archives/tech/xo-xw/63.html

[Don Pensack]

2 hours ago, dweller25 said:

By memory - so not scientific…..

Televue’s look warm.

I have a 12.5mm KK Ortho that looks cool.

I have never experimented with observing a pure white wall or snow and to be honest it is what it is and does not bother me 🙂👍

TeleVue's vary from a warm tone (Plössls, Radians, T6 Naglers) to neutral (Delos) to a cool tone (18.2, 15mm Delite) in my tests.

It depends on the glass makeup in the eyepiece.