Louis D

4 hours ago, DeP said:

Does the finderscope give me like latitude/longitude, basically if I use the skyportal app and it tells me tonight there object at this location, how can I find it in the finderscope?

I was wondering any cool apps you use? I've got the skyportal app for free as I purchased this product

The terms are right ascension and declination or altitude and azimuth, depending on what coordinate reference you are using.

I know there are some apps out there that attempt to use the sensors in your smartphone to help you find targets.  I have never used any of them, but it is my understanding you lay the phone along the main telescope tube and line it up to be parallel to it.  Because phone sensors are not precise enough to do exact locating, they can only give you a rough idea of where you are pointing at best.  However, if you don't know the skies at all, it's better than nothing I suppose.

I just realized that, at least in the summer, a noisy telescope mount isn't going to be any worse than my neighbor's ailing A/C compressor which is so loud that you have to yell to hold a conversation when standing within 10 feet of it.  I know because I replaced mine 4 years ago, and the installation technicians couldn't talk to each other every time the neighbor's started up, and the two compressors are within 10 feet of each other.

As such, I wouldn't expect any complaints from them about noisy mounts in my backyard being over 30 feet from their house.

2 hours ago, bomberbaz said:

Yes on wednesday I was trying out my 12.5mm Nikon with and without dioptrix to see if I really needed it on a 2.5mm exit pupil and found I definately didn't. The difference was hardly noticeable and certainly didn't detract from the views. M39 being a perfect object to assess this.

If you don't mind disclosing your observing eye prescription, how many diopters of cylinder (astigmatism) correction are you dealing with in that eye?  I've got 2 diopters CYL in my observing eye and notice improvement down to about 1mm, although it is subtle at that point, with eyeglasses.

4 hours ago, bomberbaz said:

Don, I notice the APM has a lip when the eyeguard is removed. What is the diameter of the top with guard removed please?  I am wondering if it is the same size at a panoptic 24mm and therefore compatible with a dioptrix!

Steve

It is an M43 thread for use in digiscoping.  As such, I believe a Dioptrx can be attached to it.

7 hours ago, NGC 1502 said:

Hi Rob. I’ve never had an observatory, however - with regard to electronics surviving extreme temperatures, all cars these days are stuffed with electronic gadgets of many types. Cars are out in all the temperature extremes, exceptionally high inside when in a hot sun, and sub zero in the depths of winter.....

Automotive electronics have an operating temperature from −40 °C to 125 °C which is very close to mil spec of −55 °C to 125 °C.  Consumer electronics have an operating temperature from 0 °C to 70 °C.

Unless otherwise stated by the manufacturer, we have to assume astronomy electronics to be consumer spec rather than automotive spec and treat them accordingly.  This not to say they could not be stored at extremes beyond these operating conditions.  I know that operating electronics under extreme heat conditions that are not designed for it can lead to permanent failure, typically due to electromigration.  Before this happens though, the device typically starts to malfunction.

I think good ventilation is key to avoid massive heat buildup in the summer (at least in Texas and the desert SW of the USA) and dampness buildup in humidity prone areas.

16 hours ago, John said:

Beats me !!!

But I thought this thread had gone into realms beyond practical usage so I thought I'd throw it in

Yeah, this thread has gone a bit off the rails:

Search on Cloudy Nights for some user reports on the ES-62 line.  They are very similar to the older 60 degree Meade 5000 Plossls if you want to dive even deeper.

I would pick up the 5.5mm Meade UWA for basically the same money (at least over here in the states, $99 vs $93).  Wider field, excellent sharpness by all accounts (it's the newest design of all the Meade UWAs), and good eye relief.

7 hours ago, rwilkey said:

Hi Steve, the great advantage in my opinion is that the 24 Pan is a 1.25", whereas the 26 Nag is not, that makes the 24 Pan very easy to use as 2" eps can be unwieldly and heavy, esp. for a smaller, lighter set-up, in other words, so I think it is more versatile.  Like John has intimated in the past, it also quickly became my favourite ep.

If you don't need the eye relief for eyeglasses, the 24mm Pan is probably the lightest option out there at 8.2 oz with good correction.  The 24mm APM UFF is 12.2 oz and the 22mm AT AF70 (2") is 16.8 oz.  Since I use mostly Delos/Pentax XL-XW/Morpheus, I'm already balanced for 12 oz to 16 oz eyepieces, so the latter two are not an issue for me.  It's when I put the ES-92s in that my balance really goes out.

I would concentrate on star clusters, both open and globular, before heading off to hunt down galaxies in light polluted skies.  The only "easy" galaxy in my experience is M31, Andromeda.  Even then, it just looks like a fuzzy cigar with a couple of fuzzy companions nearby because all you can see are the bright cores under light polluted skies.

I detect most galaxies by putting the scope on them with DSCs and then sweeping the area trying to detect a slight brightening of the background glow at higher powers.  It's much the same with comets.  To be honest, there's not much satisfaction in it except to say I "saw" it.

I enjoy sweeping star fields at lower powers now to see what shows up randomly.  It's sort of like getting in your car and going for drive with no particular destination in mind just for the joy of exploration.

21 hours ago, Don Pensack said:

One odd thing I would note: the APM seems to have a dead-flat field of view, like looking at a map.  The Tele Vue has a sharp field to the edge, but seems to be a bit "bowl-shaped"

as if the field is a tad curved--this is noted as the scope is panned while looking through the eyepiece.

I attribute this to about a 5.5% field distortion on the Panoptic compared to 0.27% in the APM..  The ES was ~4.7%

I measure the APM UFF 24mm to have a 63 degree AFOV using projection.  I measured the effective field stop to be 27.5mm, but it fuzzes out a bit, so it's hard to nail down exactly.  It's above the shoulder.  The effective AFOV (eAFOV) works out to be 66 degrees if you want to calculate the TFOV from the magnification times the AFOV.  Here's an image comparing the view through the 24mm APM UFF to others in that range.

And a diagram of the internal lenses (second from right):

The field stop is physically 30.2mm, but due to the Smyth lens, it works out to about 27.5mm as I said above.

It's a nice lens and all, providing the maximum field possible in a 1.25" eyepiece, but I still prefer the 22mm AT AF70 if I have a 2" focuser handy.  The fields are about the same (28.4mm FS for the AF70), but there is none of the fuzzing out at the edge like in the UFF due to the design pushing things a bit too far.  Both are equally easy to use with eyeglasses.

5 hours ago, JTEC said:

Another not trivial consideration is that the Pentaxes are a lot less expensive than the Delos.

Right now, only $53 difference in the states, so not that big of a deal.  The XWs only recently dropped in price here.  There used to be little to choose between them on price.  Tele Vue does put their stuff on sale once in a while here bringing the two closer.

There's a very recent thread on CN comparing the Paradigm/Starguiders to the TMB/UWA Planetaries.  The Meade HD-60s also snuck into the discussion.

13 hours ago, CCD-Freak said:

 

 

That definitely does not look like Whitesboro, TX. 😉

11 hours ago, CCD-Freak said:

I see you are also in Texas....where ya at?

 

John Love
CCD-Freak
WD5IKX

Central Texas.

2 hours ago, CCD-Freak said:

It is a little "over mounted" in the picture.  (^8

Ya think?  🤣

When traveling by car, I try to keep my telescope equipment in padded duffel bags in case the car is broken into in the parking lot.  Pelican and flight cases positively scream "STEAL ME!".  My camera equipment comes into the hotel room each night because I keep it in dedicated camera bags for easy on-the-go access.  That, and I have to recharge batteries and make backups each night.

Come to think of it, if you want a rigid case, I would get a hard-sided cooler, bubble wrap your scope, and put it in the cooler and the cooler in your car.  It will be well protected and won't be an obvious theft target.

On 12/04/2020 at 08:53, johninderby said:

The Svbony helical focuser arrived. Now have proper fine focusing. 👍🏻👍🏻👍🏻

Monuted on the Baader prism as didn’t want the weight of the diagonal and eyepiece pressing down on the side of the focuser. Focuser is quite smooth.

23 hours ago, johninderby said:

The addition of the 1.25” crayford makes a real improvement but is small and lightweight and suits the little 127 mak.👍🏻👍🏻

So, did you ditch Svbony helical focuser in favor of the Crayford focuser over the last month?  Was the helical focuser not to your liking?  How much does either extend your focal length?

I've found the Orion/Celestron/Bresser 127 Mak focuser to be fine enough for me, and pretty much backlash free, that I've never felt a desire to add a Crayford focuser to either of the two versions I've used.

I tried a 1.25" to 2" helical focuser on my Dob 20 years ago and never took a liking to it.  Much too slow to see when the image popped into best focus.  It needed a more aggressive thread pitch.

My biggest problem with plossls in fast, undriven scopes is that the image is super sharp for only a moment before the object passes back out of the center and into the not so well corrected area.  That, and you have to nudge things much more often due to the narrower field of view.  Premium, well corrected wide field eyepieces keep things sharp for a much longer dwell time between nudges.  If you're using a driven scope, then plossls work pretty well for small objects.

2 hours ago, Supernova74 said:

The advantage of being Argon purged apart from being waterproof yes basically thay don,t dew over is definitely an added bonus 

Like dielectric mirror coatings, it's a solution consumers didn't know they needed until companies started marketing them to us as essential.

I've read of observers using narrow field eyepieces to observe dim objects such as the Horsehead nebula located near bright stars.  It helps to block the stray starlight from ever entering the field of view to improve contrast.

On 13/05/2020 at 15:31, FLO said:

There are times when stellar communication and the patience of a saint are necessary to achieve a positive outcome.

Well that rules me out.  There's multiple reasons I've never been in a customer facing job, and lack of patience would be high among them. 😁

There's also the Caldwell catalog which was compiled by Sir Patrick Alfred Caldwell-Moore for amateur astronomers to highlight many showpiece objects not listed in the Messier catalog.

I take mine off each time I'm done and bring it in the house with the scope.  If I leave it on the scope while bringing it inside, I tend to whack the finder on the door frame because it sticks out so far and I forget it's there.  Luckily, it's plastic-spring loaded, so it just pops off unharmed.

I'm still on the original button cell from 20 years ago when I bought it, so it lasts a long time if you just flip it on and off long enough to get the scope on target.