jetstream

On 29/08/2019 at 06:16, Rob Sellent said:

A Vixen FL102 f 8.8 arrived safely yesterday morning.

Very nice scope!

The Nagler 3-6mm is an indispensable tool here, that being said as aperture increases it loses out in sharpness over Delos, orthos a bit. Seeing has to be excellent to notice it.

The Delos is so much easier to use compared to orthos- and I love orthos, even in the 24".

What scope is it for exactly?

1 hour ago, JCAZ said:

I put my order in for the 8mm Ethos

Congrats!

Excellent choice, and I regret selling my Ethos and Delos- my 10E was superb.

1 hour ago, GavStar said:

Gerry,

Does this nv pic of the bubble help? There does seem to be an arc close by...

Hey Gavin, good to see you posting-great image- I wonder how big the brightest seen is? I also wonder how much Hb and OIII add to it if any.

2 hours ago, PeterW said:

0.8degree “bubble”, could be the lobster claw sh157 that is not too far away and sort of loops round?

PEter

There is so much nebulosity in the area... I have focused on the Bubble neb itself and am now getting hints of a short section of the actual Bubble. I thought the same thing Peter or that close by LBN but no. Can't wait for my clearest skies Peter, and to nail down the needed eyepiece for this one, I may up the mag a hair, f4 is so flexible. The 17.3 Delos is a strong contender, I might pick one up.

Thoughts? Does NV show surrounding nebulosity around the Bubble itself?

My former 10E was a very high contrast eyepiece as was my 8mmDelos- the Delos was sharper (planetary/lunar) and deeper with similar nebula contrast. To my eyes the Ethos/Delos/Nikon HW out contrast the Nagler/ES series of eyepieces.

Sounds like you need an Ethos or Delos...

Mine open to at least 6.6mm or thereabout.

More from Mel...

One limiting factor for f7ish refractors (or others) is the lack of Ethos quality hyperwide eyepieces in the 35mm-40mm range IMHO. There is a noticeable increase in contrast when using Ethos over Nagler/ES eyepieces, at least to my eyes. This is in respect to nebula.

52 minutes ago, Davey-T said:

Well only those of us with wives 😂

Dave

Yeah, I was sure fasting dancin when I told the wife the 24" was ready to be picked up

On 03/09/2019 at 04:11, Cosmic Geoff said:

Excuse my ignorance, but I have still not grasped the justification for this project.

None of us needs to justify our telescopes or projects IMHO- this looks like a fantastic telescope in the making.

1 hour ago, Littleguy80 said:

When I did looked at the numbers on an eyepiece around 40mm I was put off by the low mag but I guess that’s probably what you want for something as big as the loop? 

The Loop is huge!

I can follow it from top to bottom under my best skies. The first thing to look for is the shade edge just off M78, the brightest section, one side brighter than the other. The 30ES in the f7 kills the Loop, the 42mm brings it out (for me). The 42mm not only gives more eye illumination but more FOV which is also needed. Before buying the 42mm LVW ask around- some don't like it, but I find it meets my needs. The big Pan might be better,not sure.

21 minutes ago, Littleguy80 said:

I haven’t tried anything at that focal length. Big exit pupil makes sense though. It’s worked well for me with the dob. The Equinox 80 is a little faster than F7 though. Would that be an issue?

Whats your f ratio? What the highest fl eyepiece you have?

Forget all what youve heard about too big exit pupil Neil IMHO...I was stuck on that for years until a member here told how he had used very large ones with success. These days I just try everything on objects to see what works. The 30ES 82 works good for me at f3.8 for instance.

5 minutes ago, Littleguy80 said:

Would the widefield frac be the better choice for this over the dob? 

It depends... in my experience the refractor used matters, for some unknown reason. My 90mm SV triplet shows it but the SW120ED is much better eventhough a smaller FOV.My VX10 does a nice job on it and the TSA120 is good on everything.

Try them all Neil!

ps the f7ish fracs love the 42mm LVW on Barnards Loop..exit pupil deal.

3 hours ago, wesdon1 said:

Would you say this is a wise decision or could you please suggest 2 eyepieces, one for low power and one for mid-high power?

Question: do you want future proof eyepieces? many buy/sell quite a lot which is fine but costly IMHO.

Used is an excellent idea!

Heres a few widefields, good ones that your F6 will like :30mm APM UFF, 30mm ES 82, 28mm ES 68, 24mm ES 82, all 2".

in 1.25": 24mm TV Pan, 24mm ES 68

The Q Barlow will give you a multitude of mags with one eyepiece... as its 1.3x and 2.25x... a 12.5mm ortho will give: 12.5mm/9.6mm/5.55mm selection.

                                                                                                                                                 the 18mm                           18mm/13.8mm/8mm selection

So, a 24mm-30mm 2" widefield and a 12.5mm-18mm ortho with Q barlow. Used Circle T volcano top orthos are very high on this list as is the Baader 18mm.

Many like BST's too.

1 hour ago, Nyctimene said:

Observing faint DSO's, or details in brighter ones, is mainly a thing of contrast, i.e. a high signal-to-noise (S/N) ratio. A certain aperture given, the signal strength (amount of photons entering the eye) cannot be increased. So it all comes down to decrease the noise. There are external sources of optical noise, that can be eliminated (observing hood/eyepatch, as you, Neil, already mentioned; observing late, in dark sky areas etc.). But there are also internal ones -the need of small muscular correction movements, when observing standing, contributes to the amount of neuronal "noise" in the brain. Therefore, observing seated is to be preferred. Alcohol increases via raising sympathetic nerve arousal neuronal noise in the same way; sleep reduces it.

But in the sensors (=retina) and the processor (=brain) a certain level of "noise" is always present. There are several complex neuronal mechanisms, based on a combination of activating and inhibiting ("lateral inhibition") properties, that enhance contrast perception within the retina and the brain.

Practice is also crucial; repeated activation of neurons in the visual system leads to the forming and growth of synaptic connections ("neurons that fire together wire together"), thus increasing the S/N ratio.

In August 1997 I observed, together with the very experienced comet hunter, Otto Guthier, the comet C/1997 J2 Meunier-Dupouy through his 16". With a visual mag of 12.2 and 3 arc min coma diameter, we both could make out the comet easily, constant in AV, sometimes directly. Another experienced observer (but not so much in DSO's) tried it again and again, without avail. I learned a lot about the importance of experience that night.

Stephan

Excellent and informative post Stephan.

17 hours ago, Littleguy80 said:

I don’t really understand how the eye and mind are working together to make this happen

Its a combination of things that add up to seeing deep, including object recognition. After being seen once objects become easier for me even threshold ones. Along the same line, when trying to go for faint galaxies forget nebula viewing first and vice versa.

Another hugely important thing to do is find the objects exact spot and then stare...trying to find very faint things panning is more difficult IMHO. The Sky Commander is helping a lot in my case.

I've read some reports under lightish skies describing some faint objects as "easy" or bright"- I think setting realistic goals for the conditions is important regards of some of the reporting...

One more- when trying a galaxy for instance, knowing its size and magnitude will help visualize what your trying to see instead of searching for a larger brighter object potentially.

1 minute ago, JCAZ said:

OMG - too funny.  I am on their website right now.  I think I can send them an e-mail and try to place on order, right.  They have the Nikon, but not the Doctor?

THX again, 

john

 

Not sure about the Docter, which is now called Noblex but they offer the Nikons and are excellent to deal with.

27 minutes ago, JCAZ said:

I thought about the direct from Japan approach but haven't had any luck.  Either I can't find it on some of the websites discussed or the pages are in Japanese and are finicky.  So for example, I tried Amazon Japan, but I think you need to create an account (my U.S. version doesn't work).  Also, the Japanese Amazon keeps reverting back to Japanese and will not translate as you go deeper into the purchasing process and get towards checking out.

https://www.kyoei-osaka.jp/SHOP/165261/165262/list.html

9 hours ago, JCAZ said:

Compared to the Nikon the Doctor is a steal, but the Nikon is two eyepieces in one.  I think it is logical however, to assume the difference in focal length between the Doctor and the Nikon is having an impact.

Youre welcome John and yes it is logical to assume this. I base my opinion on comparisons with 2 very good zooms- the Zeiss 25.1-6.7mm and the Leica Asph- at the 14mm setting the Nikon "14"/EIC goes no deeper than these 2 excellent zooms to my eyes.

The Docter is deeper than both zooms.... and my 12.5mm Tak ortho. Yes eye placement is a bit awkward.

However, for some objects such as the Eagle and Swan nebs the Nikon 17/14 has no peer, at least in comparison to the EP's I own, mind you the Docter is pretty fri cken good here too lol!

Have you considered a direct from Japan purchase?

4 hours ago, JCAZ said:

Anyone tried the NAV 12.5/10.  Pricey, but two eyepieces in one.

I have the Docter 12.5mm UWA which is my deepest widefield, it surpassed my Ethos and is an orthoscopic widefield IMHO. My 17 HW/14 Nikon does not go as deep as the Docter- some will say its because of the mag difference but no its just not as deep. Delos are VG and deep but the Docter was a bit sharper on lunar/planetary.

My deepest eyepiece believe it or not is the Baader 10mm BCO with and without the VIP barlow.

On 09/09/2019 at 08:54, Mr niall said:

maybe they've made some changes over the last couple of years.

2 hours ago, johninderby said:

You can just see the 9 point primary mirror supports. 

This cell also looks excellent, I'm wondering if all the nylon tips are supposed to contact the mirror, I see one, maybe two that aren't but they could be for something else? I had an OOUK that had some tips not contacting.

Bresser put some thought into this scope IMHO.

On 30/08/2019 at 07:27, johninderby said:

Just took delivery of a new Bresser Meesier 10” dob

This scope looks excellent- the bearings in particular and the focuser looks vg too. Nice scope

11 hours ago, domstar said:

I'm afraid I disagree with the wisdom of buying the best at the beginning.

It sure can get expensive too! and then you realize the "best" we just bought is not exactly what you want and the pursuit continues. Also, sometimes the best is not expensive- my copy of the 10mmBCO is top tier being sharper with more color and transmission than eyepiece 6x more expensive..