TelVue Delos 4.5mm.

[alan potts]

TeleVue Delos 4.5mm & 72 degree

http://stargazerslounge.com/uploads/monthly_01_2013/post-24021-0-41348100-1357675267_thumb.jpg

My reason for buying this rather long and heavy short focal length eyepiece was for Planetry viewing. Now I fully understand that there are more than one Planet in the night sky at the moment, but apart from Jupiter the others offer too smaller disc in anything but a very large scope.

I mention the size of this eyepiece because it could well be an annoying issue for Newtonian and Dobsonian scopes. The problem which annoys me a little is the eyepiece is that high when you get the scope in the wrong place you need a set of steps to climb and view. I tend to use an old chair when I have my M/N 190mm out as it always seems to be in the wrong place. This eyepiece also causes the focuser to collapse under its weight, another point that may get to some people as not everyone has Starlight or Moonlite fitted to their scopes.

For most of this effort at a review I have stuck to Jupiter but I did have a good look at M42 which is nice and high for me at the moment. I also kept to my shorter focal length scopes as it is a bit of a pointless eyepiece for a 3 meter telescope, I stopped looking for little green men on the moon years ago.

So the scopes in question are,

APM 115mm Refractor

SkyWatcher 190mm Mac /Newt

Unbranded but good 70mm Carbon fiber ED from Teleskop Services.

The mount was the same throughout, SW HEQ 5 Pro.

APM 115mm,

It was this scope that was in my thoughts when I placed the order for this Delos as it gives a magnification of X 179, which for me is top end of every night useful on this scope.

Again it was clear this was a quality eyepiece with high levels of light transmission which resulted in this clean whitish image that I have noticed on the others ( 6mm & 10mm ).

Jupiter was stunning three of the belts clear to see, the upper northern belt that sits above the equatorial belt seems to have taken a holiday, maybe it has gone to visit the clouds above England. It would be better for all if it cut short the vacation. I could also see the two polar belts, not well but they were clearly there. Sadly I was not able to see anything of the Great Red Spot but I am sure this was only a touch of bad luck. I did not notice any ghosting on this eyepiece but after saying the same for the 6mm a few nights later I saw some. I can only think I had it too far out of field because there was nothing to be seen when it was in the FOV.

Sharpness was not an issue and it didn’t matter where Jupiter was, it was sharp, and to me to the same degree wherever it was. I see this as a big plus for a Dobsonian owner wanting a high power to view Planets, or anything else for that matter.

M42,

Now I would not normally use this amount of power to view this object with this scope, for me about half of it is just right, but everyone will have a different opinion. The star cluster in the centre known as the trapezium was clear to see but I could not spot the E and F components with this aperture. All in all it was a pleasing view but for me on stars it was just too much magnification. I switched to the 10mm and this gave a better view, well for me at least. I think I could see just a fraction more nebulosity with the 4.5mm but with the image size difference I could not be sure.

I finished off with Rigel as one of the site member said in the past he was having a problem with seeing the fainter star that makes up the system and Sirius. Rigel was clear to see and very easily resolved, I have to say though my sky is much better than most in the UK, it is something like the middle of the Moors .Sirius was every colour under the sun and no, I could not see the pup with this scope, but it did not stop me looking until my hand and feet were telling to go and warm (minus 8.5C)

The views thought this scope were very clearly excellent on all of the targets on two nights of crystal clear skies. However two nights later I was treated to a sky like I have never seen, if you could buy them they would come it a nice box with a big price tag and the shop would be sold out.

ED 70mm From Teleskop Services.

Firstly I have never used these scopes for anything other than wide field viewing so this was a step into the unknown for me. I have one on top of my LX all of the time as a finder and the other just for putting my 35mm Panoptic in and loving the view.

This has a much short focal length than my other scopes giving a magnification of X 93 so for me it is in sweet spot territory for M42. What hit me on the head like a mallet was just what I could see with this scope. My very first scope back in 1972 was a 3 inch refractor from Dixons, to me it was the biggest telescope on earth, which of course it wasn’t. I can’t remember this view being as bright with a little extra objective size or anywhere near as sharp.

The eyepiece performed very well and in a 2 ¾ inch scope, I was amazed how good it was. All 4 parts of stellar nursery were there to be seen with a good deal of nebulosity, but not as much or as clear as with the APM. I then swung down to Rigel which again delivered, both stars clear to see, I have to say to my surprise.

Juptier.

Forgive me for going on about this but this scope is really punching more than its weight. The Planet was a much smaller and very bright disc on which the same three belts were clear to see, but I could not detect the polar belts, at least not at this magnification, maybe a little more is required. It will be no shock that the disc was the same sharpness wherever I placed it in the field of view but you did get this ghosting when the planet was out of view. I am not sure if this is ghosting or light scatter, maybe one of the more knowledgeable members will but me right. In any case to me it was not an issue and the only time I could see it being one would be if something else of interest was close by to a bright Planet.

Sky Watcher 190mm M/N.

Firstly this scope is not used anywhere nearly enough, it comes through me having too many telescopes and far too many eyepieces. It was luck that the M/N was out cooling on a night of astronomic bliss, Milky-way was visible right down to the horizon in the North West and M31 was easy to see overhead.

On this scope the 4.5mm gave a rather large X 222, more than I would use on Jupiter most of the time, but I know from reading posts on site many members do use this and more. The first thing I noticed was the much brighter image from the extra 3 plus inches of aperture. There is no doubt that this night would allow any scope perform well, with most of the snow gone, light rain to clear the air early on, it was indeed clear. It also turned very cold (minus 4) which made it difficult to walk about and a nightmare driving next day. Still no luck with the GR Spot, it always seems to be out of the way. I didn’t have any transits either which on 4 nights of viewing is a little unusual.

Jupiter was absolutely drop dead gorgeous, with no sign of ghosting on this scope. The ghost image had me puzzled, maybe it is down to reflector/refractor, I don’t know. I could clearly see all the belts as before but with more definition and more detail. I could also see a faint centre line belt as well as some darker patches in the other belts. The other thing was I could see the moons clearly as discs, this I have seen before but many times air turbulence (or scope not cooled down) puts a stop to it. I was not able to see any detail on them. I was left wondering after 2 hours what filters may have done to improve the night if indeed I had any.

M42mm.

Now it goes without saying this is too much power for me on this object, but I got a much better view than I though I would, the nebular filling the 72 degrees of field from top to bottom. This is a very under rated scope for visual work, I only ever see praise of it as a photographic tool. I did of course try to see the stars E and F, not that I know exactly what they are. But I guess it is the two doubles stars of the northern most and lowest of the four star pattern, I could see something in the northern most star and it was splitting into two but I could not see the lower one.. I must look this up and try again when I know for sure or take the laptop out with a good software program.

Rigel and Sirius.

Orions white search light was as you would guess very easy and fairly stable which at X 222 takes some good seeing, which I had. Sirius I could not split with the Delos but using my 20mm Nagler I could clearly see the pup star, I believe this double need not only seeing but also sharpness. I also thought I could see it with the 35mm Panoptic eyepiece, this though could have been me knowing where it was. I have just tried it again tonight and I still think I can see it with the 35mm.

So what are my thoughts.

Well 295 pounds is a good deal of money for an eyepiece that is not a regular visitor to the focuser, it’s also fairly big for this focal length when compared to a type 6 Nagler. I believe the weight could be an issue when the eyepiece is near to vertical as my focuser just gives up the ghost, matched against the Moonlite in my LX there is only ever going to be one winner. It just proves that it is not just Dobsonians that are a build project the day they are purchased.

This is without doubt a quality short focal length eyepiece as are the other Delos from the range that I have, it is also clear that little else will be as good. I like this eyepiece and its ability to perform on planets which is what I bought it for in the first place. However the extra 12 degrees FOV over say, the 4mm Radian, to many members will not be worth the additional 105 pounds outlay. It is very much a nice if you can afford it eyepiece.

I did my best to add a picture but sometimes ones best still falls short.

Alan.

[John]

Great write up Alan ! - I can see the photo too

If it's any consolation the Pentax XW's are large, tall eyepieces too - even more so in their shorter focal lengths.

Here is a diagram showing E & F Trapezium which might come in useful. F is harder to spot than E due to the proximity and brightness of C. You need to get the magnification "just right" to see these clearly, not too much, not too little:

[Damo636]

+1, another great write up Alan, thanks for posting! Those Delos are superb performers. I'm just about to head out for some astro therapy myself, first clear night in weeks here.

[rowan46]

I'm sold, it's next on my list nice write up

[alan potts]

Thanks for the map john, I looked at a sofeware program and it was showing 'C' and 'B' as being doubles. I was sure I could see the double of 'C' but I didn't notice any stars in the position that are shown for 'E' and 'F'. It may have been the small amount of turbulence that you will get when looking at stars with so much power, I can't be sure.

Alan.

[estwing]

super write-up Alan..lovely ep to have in the case!

[DirkSteele]

Very nice write up Alan. I am about to give my new 4.5mm Delos its first run out tonight at my club's next astro meeting. Will either use it with my APM 105 or my TMB 115.

Hopefully clear skies,

[Mike73]

A very nice review Alan and thanks for taking the time and sharing your thoughts.

I recently bought a 3-6mm Nagler zoom for high power use with my Lyra, as much as I love my Delos the price and limited range kept me away from seriously considering the 4.5mm, I'm sure it wont need to much of an excuse for you to use it though.

[alan potts]

Dirk,

Good luck with thw weather, and I am sure either scope will deliver.

Mike,

A point I tried to bring across was it is limited, but my, it's good. For me it was only really for the 115mm.

Alan.

[John]

Thanks for the map john, I looked at a sofeware program and it was showing 'C' and 'B' as being doubles. I was sure I could see the double of 'C' but I didn't notice any stars in the position that are shown for 'E' and 'F'. It may have been the small amount of turbulence that you will get when looking at stars with so much power, I can't be sure.

Alan.

I find my 8mm Ethos does the trick with E & F when used with my ED120. Thats only 112x but the stars are pin sharp with no diffraction / light scatter around them, which is what I find is the key to seeing E & F.

[michael.h.f.wilkinson]

Great report Alan. I might get the 8mm at some point in time (or the 6 for use in the APM F/6).

[Spec-Chum]

Superb as ever Alan!

[alan potts]

Michael,

May be you could do one on the 8mm as I will not buy one with having the Ethos, though the extra eye relief is nice.

Spec Chum,

Thanks for the kind words, how much do I owe you. I said to John earlier I used to write Specification at work now I cant even spell, and my grammer is pants. Too long having people do it for me, I'm very rusty.

Thanks again,

Alan.

[Spec-Chum]

Fiver as usual?

Seriously tho, I thoroughly enjoy reading your posts.

Even if do turn green (pun intended) with envy haha

[Stu]

Very nice, and informative review Alan, thank you.

The Delos make a lot of sense at the shorter focal lengths vs Ethos to me, field of view is less important and it must be nice having the extra eye relief.

I think, in some future life when I have some money ie kids leave school!, I will look at maybe the 3.5mm as a good high power in the 106, and maybe a 4.5 and/or 6mm for some options. I rarely use the 3 to 6 zoom above (or below?) 4 or 3.5 mm anyway, so having a dedicated ep at this level makes some sense to me.

Might have to look into all this Pentax business too, they do seem popular......options....too many options!!!

Stu

[E621Keith]

Thanks for the great review Alan.

I wonder how the Delos compares with the 5mm XW.

[alan potts]

Keith,

A very good question, I was going to buy one until I Powermated the 10mm Delos and came to think , if anything can better that image, I have yet to see it. If a 5mm Nagler comes along then I will get one, the 5mm XW is over 300 pounds for me here. These Delos are really good, I started on the 10mm last night then the mount packed up, so I repaired it, I think the 190mm M/N is too big for it.

All I could do is maybe do a head to head with a 4mm Radian or a 5mm Radian, I believe that it is better to compare with another company, for me the Delos 4.5 and the ExSc 4.7mm would be good.

Thanks for the kind words,

Alan

[Mike73]

Just popped in for a quick cuppa after viewing Juipter for the last 1 1/2 hours with my Lyra.

I've been viewing at x220 with a 3-6mm Nagler zoom (@5mm) and a x2 barlowed 10mm XW and at the moment the XW comes out on top. Its the contrast (and maybe a little sharper) on NEB/SEB/STB which wins it not by much at all but to be honest I'm quite surprised.

I've always noticed my XW's have better contrast than my TV's but have never really noticed it on planets before.

I wish I had your Delos right now Alan!

[Damo636]

Mike

I often barlow the 10mm XW down to 6.25mm with the Antares 1.6x & it works flawlessly. I would go as far as to say the 10 XW is the best ep in my box!

[alan potts]

Mike,

To be honest, I would always expect a high quality eyepiece like the Pentax to beat a zoom, Barlowed or not, even a Telvue zoom. I don't find a Powermate has any effect on the image at all. I have done things like PM and 20mm Nagler against the Delos 10mm and there realiy is so little difference and I am sure that is only due to the optical design.

I would like to see a match againt 10mm XW and the 10mm Delos, that would be a good one. To me it would be a, do you like Kerrygold or Lurpack?

I wish I liked a bit closer I would lend you it.

Alan.

[DirkSteele]

I thought I would follow up with my thoughts on the Delos 4.5mm. I used mine for the first time at the monthly meeting of the Baker Street Irregular Astronomers in Regents Park on Wednesday night. The event was run in conjunction with BBC Stargazing Live and there were 3-400 people in attendance at the peak. Queues were often 10+ deep for a look through each of the telescopes on offer. I took my smallest scope, the APM-TMB 105 F/6.2 Triplet Apo, mounted on a manual Teleoptic Giro Ercole Alt Az mount.

In the 105, the Delos 4.5mm provides a magnification of 145x and a true field of view 0.49 degrees. The seeing conditions were quite good. The transparency was decent, and higher power work indicated the atmosphere was quite stable.

I agree with Alan, the EP is quite long (quite a bit more so than the 10mm Delos which is one of my favourite EPs). Fortunately all my scopes come with Feathertouch focusers, so the size and weight is not a problem, but it is something to be aware of.

We are somewhat limited by the objects we can view from the centre of London, and like Alan, Jupiter and M42 were the two primary targets when using the 4.5mm. I also used it to view each open cluster in the Perseus Double Cluster in turn (though the view of this object in the 10mm is wonderful as it nicely frames both).

Starting with Jupiter, the image was incredibly sharp with very clean, pure colouration. Some EPs are known to show colour either slightly warm or cold, but here Jupiter looked incredibly natural. Echoing Alan’s experience, no matter where Jupiter was positioned in the field of view, the image was incredibly crisp and showed no degradation what so ever. 3 belts were easily visible (Red Spot was on opposite side of the planet). I allowed the planet to drift out of the field of view, and it was not until the planet was over 75% past the field stop did I detect the smallest amount of violet colour fringing around the trailing edge of the planetary disc. I lost count of the number of “wows” I heard when people looked at Jupiter through my scope, and a good number commented that it was the best view they had all night, despite the 40 or so scopes present. The TMB lens in my scope is truly first rate, but I think the Delos certainly did nothing to negate the scopes ability.

I also had my Nagler 3-6mm Zoom EP and comparing the image using the 4mm and 5mm click stops, I would say the Delos took it. The Nagler Zoom in previous tests we have conducted at the BSIA has more than matched any fixed focal length EP we have thrown at it, but I found the Delos just shaded it. Plus the slightly larger field of view of the Delos meant I could spend more time observing rather than repositioning the telescope to chase Jupiter across the sky. Though I do not wear glasses, the extra eye relief makes it more relaxing EP to use as well.

Moving on to M42, I agree with Alan that this is way more magnification than I would normally use, but to compare experiences I gave it a go. The central region of the nebula around the Trapezium cut through the light pollution of London remarkably well, and it was a pleasing view. The “E” component of the Trapezium was visible but “F” proved to be elusive.

Each component of the Double Cluster was viewed in turn, and allowed to drift from the field of view. The stars were pinpricks of light all the way to the edge with no distortion visible what so ever.

Overall I am very pleased with the performance of this EP and it is hard to say a negative word against it, other than perhaps the size and weight if you have a light weight focuser. Highly recommended.

[Damo636]

I would like to see a match againt 10mm XW and the 10mm Delos, that would be a good one. To me it would be a, do you like Kerrygold or Lurpack?

Alan.

Its Flora Light for me Alan, Christmas has not been kind to the waistline :-)

In my experience, there really is nothing to pick between the 10 Delos & the 10 XW. I sold the first two XWs I owned & replaced them with the 10 & 6mm Delos. Optically I thought they were pretty much as good as it gets, but ended up going back to the XWs, purely because I preferred the ergonomics of the Pentax eps. One thing I was less than impressed with though was the fibre ring on the field lens of the10mm Delos. There have been reports of this falling out and I remember watching it flex with the blast of air from a bulb blower! I think its reasonable considering the cost of these things, that something a bit more secure, maybe a threaded baffle, would have been a better solution here?

[DirkSteele]

One thing I was less than impressed with though was the fibre ring on the field lens of the10mm Delos. There have been reports of this falling out and I remember watching it flex with the blast of air from a bulb blower! I think its reasonable considering the cost of these things, that something a bit more secure, maybe a threaded baffle, would have been a better solution here?

I was concerned about this before I bought the 10mm Delos as well. I spoke to David Nagler about this when he visited London last year and he said that Televue had prepared a number of kits for repairs and so far (this was October 2012) only 3 customers have actually reported the problem. So perhaps there was a bit of an over reaction (certainly on Cloudy Nights), though when spending £300 on an EP, it is fair to assume it will all be first rate materials.

[alan potts]

Dirk,

Nice revoiew, very nice in fact. There were a few thing s there, saw, and wish I had mentioned.

Can't stop, it's my Birthday so off out for a beer.

Alan.

[DirkSteele]

Can't stop, it's my Birthday so off out for a beer.

Happy Birthday! Hope you have a great day.