Deadlake

1 hour ago, Highburymark said:

Wow - I missed that it is a 6”!! That’s a definite ‘no’ from Mrs Highburymark.

Is 900 mm long, not much off your 4”. 😃 

however how well corrected the scope is another question, not sure if they will get close to 0.95 Strehl, for that fast a scope needs a triplet. 

3 hours ago, Highburymark said:

Admittedly, very little. SW Esprit 120mm is 3.6kg heavier for the basic OTA. APM sadly doesn’t do a direct competitor. Otherwise it’s larger Chinese triplets: The TS triplets are 130mm and like the Esprit, over 10kg. Not including the Vixen 115 as it’s a doublet. 

You could look at this:

https://www.cloudynights.com/topic/776901-new-apm-6“-f6-sd-apo-design-need-your-all-input/

A New APM 6“ f/6 SD Apo

The f/6 speed should mean with your NV device very effective when used with hydrogen filters.

About 10 kg in weight, but given the price very attractive. 

23 hours ago, Highburymark said:

Excellent report on a mount that’s had little coverage on SGL. I’ve got the Rainbow RST-135 and so far am also very happy with it. Agree with you about not wanting to push the payload too far. I currently run mine with a 7kg scopes - might go up to 8-9kg in future but not more. Also agree that traditional mounts are the way to go if size and weight aren’t an issue. These mounts are all about compactness and incredible performance - and not having to be too precise with balance.

How do you go about aligning either of these two mounts if you want to use in visual in ALT-Z mode?

Seems a little overkill to have to use a pole master or sharp cap.

In fact I'm not sure why its not built tin to the device??? 

6 minutes ago, mtminnesota said:

Mine is alt-az. 

It works very well with a FC-100, so apparently it would work with the Vixen too.  This video shows how solid the FC-100 is on it.  I would add that I've found it's more solid when the arm is vertical, making it better balanced on the tripod that when it's leaned back.  Of course you won't be able to observe close to the zenith, but the more vertical the better.  

 

The mount is ridiculously easy to align with SkySafari.  Connect to the mount via wifi, type in the IP address, port, etc., then point the scope at a known star, click on it in SkySafari and hit "align".  No need for Polaris or multiple stars.  I assume the mount should be pretty level as well, but it doesn't mention that in the instructions.

Thanks, I already have the Scopetech Zero, hence the interest. I've been using more and more then my SXP2 as so much easier to get setup with. 

Interested to hear you get on with the tracking kit, hopefully will be the most flexible in portable guided mounts. 

47 minutes ago, mtminnesota said:

The tracking kit and a Mount Zero, just out of the box.  The motor cables and connectors are of high quality, reminding me of audiophile equipment.  Everything appears well constructed, but it is a minimalist drive kit so it looks sparse with its exposed motors and wires.  Is this mount worth the $1325 it costs with the drive kit?  Maybe, if you want something unique, compact, and hand made in Japan.  I haven't observed with it yet, but I'm expecting it to perform well and last a long time.   

Do you think would work with a Vixen SD103S scope, same size as a Takahashi FC-100 scope?

Is this the Alt-Z or GEM flavour?

How do you align the mount?

Thanks

11 hours ago, Trentend said:

I came close to getting the tpod (which looks like a work of art) to save a few pounds in weight but have no regrets with the planet: no grating noise when you extend the legs

The t-pod is the only tripod I know of with a built in handle. Should gain some followers here... 😀 Agree on the scope zero, needs some more fine motion controls. I wonder when the AZ50 is coming out???

@ecuador

I don't know if this feature request has been discussed, but if the phone could be attached to the polar scope could it not do plate solving?

 In this way you would not care about the interference to the phones compasses etc?

I think that some of the Celestron apps can do this to guide observers around the sky.

Best wishes,

Martin

2 minutes ago, DaveS said:

ASA make their own optics, up to 2 metre class.

They do but they also use GSO mirrors as well, so their UK dealer tells me....

GSO has a machine for producing mirrors by which all accounts is very good. They supply mirrors to other vendors such as ASA (very high quality)  and CFF as well.

30 minutes ago, JeremyS said:

And?

Waiting, I guess quite a lot of people would have overlap (share a nexus) with the AZ100?

Asked Sergi at astrodevices if there is a digital circle encoder kit. Not the first person who has asked. 🧐

On 04/05/2021 at 21:06, Deadlake said:

Now @FLO

https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/scopetech-goto-controller-for-mount-zero.html

Wonder if it works with a nexus?

No info on weight limit, very portable 

And hopefully a review

https://digiborg.wordpress.com/2021/03/25/scopetech-mount-zero-5/

 

 

The motorised goto mount seems to of been pulled, any ideas why?

12 minutes ago, Stu said:

https://www.firstlightoptics.com/stellamira-telescopes/stellamira-104mm-ed2-triplet-f6-25-apo-refractor-telescope.html
 

??

Is that fabricated by Long Perng? Even so just because it’s the same factory different specs, happens a lot with EP’s and scopes..

Wonder what the back focus is, 96 mm,  very short…

1 hour ago, John said:

The ED102SS weighs around 4kg with tube rings and a diagonal fitted.

Today's nearest equivalent is the 102mm F/7 FPL-53 doublet refractors of which there seem to be versions by Telescope Services, Altair, Technosky etc.

 

This model was also an option

https://www.365astronomy.com/apm-telescopes-super-ed-apo-astrograph-107-700-apochromatic-refractor-telescope-with-3-apm-focuser

is F6.5, it’s been discontinued due to SharpStar quality control issues. However there is a Long Perng 104/650 built model for APM in the pipeline with an optional Starlight FT focuser option. Not LZOS but half the price.

35 minutes ago, John said:

I use either a Skytee II or the Giro Ercole.

The Ercole needs the axis lock to be used when switching heavy eyepieces. The Skytee II has enough "sticktion" in it's axis to handle the changeover without the need to lock the movement.

 

 

Any idea what the modern day equivalent of the Vixen ED102SS (F/6.5) would be?

I'd imagine the weight would be similar to the SD103S.

On 03/06/2021 at 10:16, John said:

I can bring my Ethos 21 and Nagler 31 to focus with my FC100-DL using a 2 inch diagonal. It's not the optimum wide field scope though because of the focal ratio. I have a Vixen ED102SS (F/6.5) which is my widefield frac. These eyepieces also come to focus in that with around 15mm of inwards focuser travel to spare.

 

What mount do you use with say a Ethos 21 and Vixen ED102SS (F/6.5)?

When I use my SD103S on a ScopeTech Zero with an APM XWA EP the scope will move any time I change an EP due to the larger then usual weight of the EP. 

11 hours ago, jetstream said:

Everyone should have a large aperture dob IMHO, if circumstances allow. A 1/10 wave mirror, .98 Strehl is not needed- just a nice smooth 1/4 wave system is all thats needed. They really do show more of DSO than other scopes, under dark skies espc.

With your dark skies @jetstream you can see quite a lot due to the contrast you have.  Even with your TSA-120. However with portability in mind to get to a dark sky a smaller scope might be the answer. I’d imagine a Mewlon 180 would be very good  which @Fedele already has. Presume that’s not portable enough???

7 hours ago, Space Hopper said:

Yes a Feathertouch. In for a penny, in for a pound.

Yes, the GPC is definitely needed for high power, but not for low. With my 24mm @ 27x i can nicely frame M45 into the field of view.

My scope is the F6.2 version.

 

Interested to hear what the differences are between standard and uprated version. It’s not although I’ll be able to order one anytime soon, given the availability of lens cells…. Next year, however the FT and rube adds a thousand to the price…

In addition what it performs like once barlowed if possible. You can always add focal length but cannot take it away, without cutting the tube. 😃

I know Takahashi Q extender might be an option, works with AP scopes as well.

52 minutes ago, Space Hopper said:

The refractor in question is currently going modification.

Its current 2.5" focuser has a drawtube length of 90mm, and will allow focus with a bino sans GPC.

However, with the 2.6x gpc in place i run out of focus to where the focuser is fully racked out.

I can get it to focus by pulling the whole rig out and unseating it about 10mm or so but this is far from ideal.

I'd imagine a 2" diagonal and big 2" glass would be a similar situation, although i don't currently have any 2" eyepieces to test that.

The focuser on my scope has its limitations, so i'm upgrading it for something more robust ; not just for binoviewing, but for future imaging plans as well.

Are you saying get a FT for it?  😃 GPC aren't hat bad, needed for correcting the prims in the bino originally?

Is it the F6.2 or the F8?

Thanks

30 minutes ago, Stu said:

It’s not really about focal ratio per se, more the actual focal length, although if just talking about a 4” scope then of course it is all related.

The 31mm Nag shows about 3.4 degrees in the Tak FC100DC and about 5 degrees in the Genesis. The Tak is a little tight for the whole Veil at 740mm focal length, 3.6 or 3.8 is more comfortable, but the Genesis is fab for these objects at 500mm focal length. It is a petzval design so has a nice flat field, little or no field curvature.

An NP101 did cross my mind as well..... Genesis no longer available.

An FSQ-106 from RO is around £4000, a little cheaper then the LZOS mark II  and you can actually buy.... 

11 minutes ago, John said:

I can bring my Ethos 21 and Nagler 31 to focus with my FC100-DL using a 2 inch diagonal. It's not the optimum wide field scope though because of the focal ratio. I have a Vixen ED102SS (F/6.5) which is my widefield frac. These eyepieces also come to focus in that with around 15mm of inwards focuser travel to spare.

 

Presume a wide field scope needs a F ratio faster than F7?

@Stu Thats a good idea. Additional requirement is to have 220 mm of focus range to support Bino's as well without a GPC. 

A DF or DZ could do this if FT?

Cheaper then a LZOS, which will not be available until sometime in 2022...

27 minutes ago, Space Hopper said:

Maybe a SW Esprit 100 ?

That should give you the wide field views you are after ?

SW  Esprit 100 has a back focus of 183 mm, not enough.

What about your APM 105? 😃

For portability reasons I'd like a 4" refactor (Doublet or Tripet) that can support 2" eye pieces. I have at present a SD103S that I can use with APM 5, 13 and 17 mm XWA's by using them with a 1.25" fitting to a Baader T2 prism diagonal. However when trying to use the above EP's with a Baader 2" dielectric diagonal there is not enough infocus. A 2" Baader prism diagonal has an optical path of 100 mm, that saves 12 mm over the 2" dielectric optical path of 112 mm. This will not be enough, the issue is the scope.

I'm looking for a scope which will support the 20 mm APM XWA and an APM 30 UFF. These need a 2" diagonal. 

I suspect a Takahashi 100DL would have the same issue of not enough infocus either.

Is this correct?

The only option I've come up with is a LZOS 105 mm/F6.2, focuser will have the range to support the EP.

Any other ideas or options? I'd need to cut the tube for the SD103S to work.

 I like the Vixen SD103S however I like the wide field views more.  

 Interested in 100 mm scope, not smaller or bigger.

Also supported Bino's without a GPC would be good, back focus of around 220 mm.

Thanks

How much wide field viewing would you imagine doing with the scope, e.g. with an Ethos 21 mm or APM 20 XWA? My SD103S does not have enough infocus for either of these EP’s so I need to use another scope and I suspect the 100DZ has the same limitation. The APM 140 will not had the focuser has the range to accommodate these EP’s.