Skylight F13 First Light

[Marki]

I recently took delivery of a Skylight F13 made by Richard Day - I had set it up once to have a look at the moon a few days ago, but tonight was its first real test.

This 4" long focus achromat owes a lot to the Victorian and Edwardian classical refractors, with its beautifully finished black tube, with brass dewshield (I know some may prefer the classic white tubes...I know I did with my TALs, until now). The scope is based around a quality Japanese (Carton f13 100mm) objective, and is complemented by a Baader steeltrack focusser. It is fitted with a brass bodied finder as well - and this is quite sharp and has a cross-hair reticule). At approximately 1.45m long (once I've put my Williams Optics dialetric 2" diagonal in it), its about as long as I can comfortable manage. For the present it is mounted on a Skywatcher EQ5 with 16" extention pillar - if anything this is slightly undermounted, and there is a little vibration when using the focusser. Following advice from several experienced members here, I'm looking into getting 2" steel tripod legs, and spacing the tube rings further apart, on a wider dovetail plate to increase stability. A more arcane suggestion is to make/fit a Hargreaves strut, although this may tax my very limited (read non-existant) practical skills .

Conditions tonight - a relatively clear sky, with reasonable seeing but increasingly washed out by the waning three-quarters moon. Clouding over now, hence me coming in to write this little report .

Fitted a 1.25" 20mm wideangle (Teleskop Service GSO clone), my first target was Mizar/Alcor at a gentle x65 - the system split cleanly and sharply as you'd expect. Switched to Albireo - gorgeous colours, but regretfully it was soon lost to view behind my house. I then headed up to Lyra and the double double, intending to switch to a higher magnification for a split, but I was stunned to see that both systems split with the fitted ep! Very tight admittedly, but nevertheless separated at x65! This is considerably better than I have managed the split before (x76 is my previous best). Perhaps the seeing was steadier than I had orginally thought, maybe I'm "getting my eye in" with practice, or maybe the Carton objective really is that good. Had a quick peep at M57 (partly to see if I could remember where it is - its one of those objects that I find elusive - no idea why ). A little grey smoke ring as always, but pretty washed out by the increasing moonlight.

The moon was well above the trees by now, so I decided to skip any more fuzzies. Indeed the moon was so bright now that I could barely make out the Pleiades with the naked eye. So, on to Vega, and I whacked up the magnification to an optimistic x260 (Baader Genuine Ortho 5mm) to star test the collimation (not that I needed to from what I'd seen so far). So far as I can tell, and given my limited experience, its pretty much spot on, with near perfect diffraction rings inside and outside of focus. Richard Day prefers to deliver his telescopes personally, rather than trust a courier, and I am glad he does - the telescope clearly hasn't suffered in transit !

Next I decided to head for Jupiter. Back to the 20mm - the planet is beautiful and clear with well defined brownish bands and four moons strung out in a line to one side. The 5mm was way too much for the conditions, so I decided to get out my Hyperion MkIII zoom, with the 2" fitting. I had pleasingly crisp and detailed views of Jupiter down to about 12mm (x108) but when I went to 8mm (x162), the resolution just dropped.

Finally on to the moon. So bright...forgot to add a filter, and I can still see the after images :eek: ! But stunning, crisp high resolution images on the terminater and on the main body. I need to do some moon research to learn what features I was seeing, but the detail was great down to 8mm with the zoom. So good, I switched in the 1.25" adaptor and whacked in the 5mm again (x260). Blown away by the resolution. I have never seen the moon like this before, and I confess to getting a wee bit emotional and peppering the air with a few expletives in delight .

So, impressions? The scope is beautifully finished and its quality in workmanship speaks for itself. Some may find the brass dewshield (which is functional as well as decorative) and trim a little excessive, but I think it is cool . It is gorgeous to look at and to look through. The optics are excellent (as I suppose we'd expect for the Carton objective) indeed, with clear crisp images with lovely colour and great light transmission. It holds focus really well, and has the good focal range/depth that a longer focus refractor provides (noticeably different from the f10 TAL100RS). The focusser is really smooth, and I never felt it would slip, even with the Hyperion in it (sometime that seems a wee bit heavy for the TAL crayford, if I use the 2" diagonal and I have to make sure its well screwed it). As for the dreaded CA? Virtually negligible - barely noticeable on Vega, and a very limited trace on the moon (if I looked for it) and nothing on Jupiter that I could see (a bit hard to judge on this target given the general Moonlight pollution ;-)).

I can't wait to give this telescope a more thorough outing and try some tighter doubles, or see how it fares with globular clusters. Based on the two hours I had tonight, this thing is easily the best 4" I have yet had the pleasure of looking through. Admittedly that is a small selection so far, but it beats my TAL100RS hands down, and tramples allover the Starwave 102 ED (an f7 "semi-apo" with FPL51 glass) I had earlier this year. I'd like to mount it side by side with my TAL125r and see how they compare...if I find a mount able to deal with that .

I may have finally found the scope I've been looking for ... (until someone gives me a view through the 6" F15 version.. ).

[John]

What a super looking scope Mark

Sounds a good performer too from your report.

You can check the collimation using a simple cheshire eyepiece if you want to but it sounds on the money from your star test.

I look forward to more pics of it and more reports soon !

[Jem7]

Even the finder scope matches, what a stunning scope!.......A very enjoyable report too.

[johninderby]

Glad to see you are impressed by the new scope. Very good report. The Carton 100 is something special all right. Mine would beat my old WO FLT98 for sharpness and contrast.

I use mine on a Skytee 2 which doesn't even notice the load, very solid.

John

[Scott]

Great read Mark. Thanks

Scott

[nightfisher]

Excellent Mark, glad you finally got first light, its a lovely looking refractor with super sharp optics

[AndyH]

Mark - Truly thou art a refractor-o-holic

My 60mm Carton lens is awesome. Can't begin to believe how good the 100mm must be.

The more I look through my toothpick and the more I read about other Cartons, I'm starting to understand why TeleVue used them for bits n pieces in their early days.

Andy.

[VigdisVZ]

Thank you for this nice report. And congratulations on your very steampunky scope!

[Marki]

Nice one Carl - steampunk is exactly the word my wife used when she saw it .

[Marki]

I had another nice session tonight, notwithstanding the firework haze and some high thin cloud earlier. Main target, Jupiter (and why not...?). 15mm BST ed explorer and televue 2.5x powermate for x216 first in the tube. The image this produced was ok but not as sharp or contrasty as it might be. Better definition with a 20mm TS branded GSO wideangle (rapidly becomming one of my fav eps - really versatile) in the powermate...lovely crisp planet with the four moons strung out, three behind and one ahead. I really enjoyed the excellent focussing the two speed baader steeltrack gives - the planet really does "snap" to focus! Generally roamed around Cassiopeia and Andromeda (double double lovely, M31 too big to see and its too hazy for much definition of what you can see). Had a quick look at Castor (alpha geminorum) - clean split at x65. Finished on m42, and got the trapezium nicely at x162 (with a hint of one of the smaller stars on the right hand side). Nebulosity pretty vague, even with averted vision, but that I think is due to the moisture freezing out of the air, and the moonlight.

I tried all of these targets on Saturday night with my TAL125r and with the same ep combos (albeit with the tal 1.25" diagonal as opposed to the WO 2" on the Skylight). I wanted to see if the Carton 100mm f13 objective's longer focal length and excellent quality would make up for the inch in aperture the Skylight concedes to the 125. I was particualy intersted in this given that the Skylight seemed so effortlessly better than the TAL100rs. Allowing for the conditions, I'd have to say the TAL edges it - that extra 25mm really does make a difference, especially when at low and medium magnifications. The Skylight appears to be better colour corrected though (a function of the longer focal length I guess). The Skylight performs better at higher magnification too, but I still have a problem with the TAL at over x120-x140ish - once that is resolved, I think the TAL would clearly regain the superiority that the extra aperture should give it. Having said that, the Skylight is clearly superior in fit, finish, workmanship and quality of materials, and this is especially noticeable in the focusser - the Baader steeltrack is simply way better quality than the standard crayford that the TAL sports.

A fun session, but boy am I cold now! This is the first time I've been out and actually had frost on the tube!

EDIT - just reread this post. I think I'll have to give the 100rs another chance...I love that scope so much . Its big sister clearly holds her own still, compared to the Skylight (at least in terms of the advantages the extra aperture brings), so Little sister deserves another light to show off the undoubted quality of her optics, even if her wrappings are more basic. Maybe after a few sessions, I'll be less seduced by the skylight's exotic decadent capitalistic charms, and so can be more objective in my assessment

[nightfisher]

Excellent write up Mark, i wanted to get a scope out but up at silly oclock

[Qualia]

Loving thread, and great write ups, Mark. It's a beautiful looking instrument

[Damo636]

Lovely looking scope Mark, I would sooooo love one of those!

[Duns]

Great report Mark - I love the scope, looks great and appears to tick all the boxes.

[John]

Another good session with your refractors Mark

Any idea why your 125R is not yet quite on song ?.

I'd expect an 100mm F/13 achromat to show noticeably less CA than a F/9 125mm to be honest assuming that these are good examples of both, which they are.

I'd love to compare my Vixen ED102SS F/6.5 to a Carton 100mm F/13. I did manage a quick comparison with one of the Skylight F/15's at an SGL star party but the Skylight was out of collimation so it was not a fair match, unfortunately.

When you get a chance, try your refractors on Eta Orionis. It's easy to find near the higher end of Orions belt and it's a challenging test for 4" - 5" scopes I think.

I'd hold on to your TAL100 if I were you. They are great scopes and very rugged

[Merlin]

Is there enough in-focus for a binoviewer, or do you intend to stick with Cyclopian viewing?

[philj]

Congrats on the scope mark, theyvare nice arent they? Black and brass is the proper colour for a scope imho. Sounds a good performer, I was well impressed with the f15 when I test ran one, if I didnt already have my old f15 I would certainly have a skylight

philj

[AndyH]

Loving thread, and great write ups, Mark. It's a beautiful looking instrument

I 'second', all three points.

Keep the reports coming.

Clear sky's, Mark

Andy.

[Marki]

Thanks for all the support .

I'll definitely try Eta Orionis next time I'm out: thanks John - its up and above the trees for me at just before midnight now.

A few more more images for your delectation... .

Still not happy with the TAL yet...I'll have yet another general "fettle" this weekend to see if I can make any further improvement. I'm also planning to dismount the objective and check it over (had some helpful tips on how to do this from various members now). Failing that, I'll have to get it seen to professionally. I've been in contact with Es Reid at Neil English's suggestion - Es suggested a quick check to ensure the elements are correctly oriented and that the rear element is not reversed or anything; plucking up courage to do this! Anyway, another pic to show size comparison of the 125 with the F13.

Will keep you posted on progress .

[nightfisher]

Nice pics Marki, good luck in getting the tal up to its best, take your time if you choose to "float" the lens out, pm me if you need further help

[F15Rules]

Hi Marki,

Just picked up this thread, very belatedly, but just had to say how much I enjoyed reading your write ups on your beautiful new refractor. Your delight and enthusiasm really come through and as Jules said, it just makes you want to get your own scopes out!

Do keep the reports coming once you have a really dark moonless clear night ...say in about 5 years then!

congratulations on a lovely scope

Dave

[Mike73]

Wow!! Mark that is a seriously beautiful telescope!!

Clear skies.

[SnakeyJ]

Hi Mark,

An absolute stunner - form & function, perfection and full credit to Carlton. How long till you splurge on the 6"?

Lovely prose and a great read - keep it coming.

Jake

[SnakeyJ]

Hi Mark,

An absolute stunner - form & function, perfection and full credit to Carlton. How long till you splurge on the 6"?

Lovely prose and a great read - keep it coming.

Jake

[JamesM]

Thank you for your observations Mark - makes very interesting reading, though I think I'm now getting a little dehydrated with all my dribbling! :grin:

With my new bib tightly secured await further reports.

James