I have mixed feelings about my 10” dob…

[michael.h.f.wilkinson]

2 hours ago, Victor Boesen said:

A maksutov seems like a very portable solution. Since you mention the Celestron C OTA's, do you know how their SCT design would compared to the maksutov with regards to cool down, sharpness and etc?? The Celestron C5 looks to be the same weight as the skymax 127, but it has a shorter focal length.

EDIT: Doing a little reading myself, it doesn't seem like the Celestron C5 would be a better option than the skymax 127.

The C5 has a larger central obstruction than the Skymax 127. However, the C8, at the same weight as the Skymax 150 can get more detail on planets. I used to have a 6" F/8 Newtonian, which had very good mirrors and a small CO, but the C8 definitely gave more detail on planets, even if contrast at the same exit pupil was a shade less. 

[Victor Boesen]

Thank you all for your great advice with regards to my decision with the dob and any other replacement for it!!

@johninderby Your comparison with the three scopes is very useful to know! If the difference between them is so small then I'd say the Skymax 127 is still the best choice for me.

@Wiu-Wiu Thanks for pointing out the disadvantages of the SCT;))

@Nik271 Great to know that cool down time isn't a big problem with the mak!! This was something I feared would ruin the grab and go part of it;)

34 minutes ago, PEMS said:

The idea of a 100ED seems good, have you seen one?

I haven't seen one in person actually, but I'd imagine that the tube length would be comparable to the length of my dob? I know someone not far from me who owns one, so I might ask him if I could swing by him and have a look at it/through it before I make my final decision. I would probably end up buying another tripod no matter what, but I would imagine a steel tripod with a sturdy alt/az head would do the job? I'm also really a fan of the 100ED because , 1: It's a refractor and I know somewhat what to expect based on my 72ED, 2: The focal length doesn't limit me to only observing doubles and high power views of the moon and planets compared to the Bresser/Skywatcher maks which have a lot longer focal lengths. Since the 100ED is also supplied with a case I'm very confident I could still grab the scope, eyepieces in the case and a mount all in one go. Compared to my dob this is not possible at all.

Thanks again for your replies! I am more confident that selling the dob is the right decision, but I still have to take a couple days to actually sell it

Victor

[Victor Boesen]

25 minutes ago, michael.h.f.wilkinson said:

The C5 has a larger central obstruction than the Skymax 127. However, the C8, at the same weight as the Skymax 150 can get more detail on planets. I used to have a 6" F/8 Newtonian, which had very good mirrors and a small CO, but the C8 definitely gave more detail on planets, even if contrast at the same exit pupil was a shade less. 

Would the larger central osbtruction result in worse performance under bad conditions(and less contrast in general) compared to a mak with a smaller obstruction or a refractor without an obstruction?

Victor

Edited September 20, 2020 by Victor Boesen

[Alan White]

Victor, having read your initial question and then the developing one, I get the feeling you had already decided to sell the Dobson anyway and wanted confirmation of this decision made.

Changing scopes about for many is part of the hobby, it’s actually fun trying differing scopes anyway, so sell one buy one is very common, but does cost money.

I have been observing for decades and churned scopes and kit to suit my situation and finances over the years, but have settled to one refractor and one reflector. 

My home setting differs from you as I have a garden and I also have a car to go to dark sites with, so this allows the scope choices made.

I think your idea of a refractor and larger but portable reflector makes great sense, but do not get hung up on planets and lunar only, it’s a great but limited target list, dso of the brighter kind in light pollution as well star clusters and doubles should be on your observing list.

Sell the 250 and move on, it’s a journey of discovery, so enjoy the trip.

[michael.h.f.wilkinson]

1 hour ago, Victor Boesen said:

Would the larger central osbtruction result in worse performance under bad conditions(and less contrast in general) compared to a mak with a smaller obstruction or a refractor without an obstruction?

Victor

Larger CO reduces contrast regardless of conditions. Dependence on seeing is largely a function of aperture, mainly because larger apertures can only show more detail than smaller ones if sering allows. I don't ever recall conditions where my C8 showed less detail than my APM 80 mm F/6 triplet. At the same magnification, the image in the C8 was always much brighter and crisper. 

[Victor Boesen]

2 hours ago, Alan White said:

Sell the 250 and move on, it’s a journey of discovery, so enjoy the trip.

Thanks for confirming my decision:)) With regards to getting hung up on planets and lunar, I think this has to do with the light pollution level where I currently live... I usually do some deep sky observing at my grandparents house either with my Helios Apollo binoculars or my small Evopstar 72 since it's  a Bortle class 4 location:))

[Nik271]

6 minutes ago, Victor Boesen said:

Thanks for confirming my decision:)) With regards to getting hung up on planets and lunar, I think this has to do with the light pollution level where I currently live... I usually do some deep sky observing at my grandparents house either with my Helios Apollo binoculars or my small Evopstar 72 since it's  a Bortle class 4 location:))

Light pollution is also my reason to go for long focal length scopes and concentrate on solar system stuff and double stars.

My personal gear path was: Astromaster 130 EQ, then Skymax 127 and now I'm using a Skymax 180 which stays cool in a shed in the garden. 

Also don't forget the planetary nebulae, some of the small ones are quite resistant to light pollution.

Clear skies!

 

[Highburymark]

There’s also the C6 Victor. Very portable and flexible scope, which will show more detail than the smaller Mak - though the Mak will win on sharpness. However, I’d be tempted to for a larger refractor - 100ED. Whatever your decision, good luck.

[Alan White]

2 hours ago, Victor Boesen said:

Thanks for confirming my decision:)) With regards to getting hung up on planets and lunar, I think this has to do with the light pollution level where I currently live... I usually do some deep sky observing at my grandparents house either with my Helios Apollo binoculars or my small Evopstar 72 since it's  a Bortle class 4 location:))

Victor, could you perhaps negotiate the Dob living with your Grandparents?
 

[Victor Boesen]

49 minutes ago, Highburymark said:

There’s also the C6 Victor. Very portable and flexible scope, which will show more detail than the smaller Mak - though the Mak will win on sharpness. However, I’d be tempted to for a larger refractor - 100ED. Whatever your decision, good luck.

Thank you very much. I'm leaning towards a larger refractor and more specifically the Evostar 100ED DS-Pro, but I think I'll try to do some more research with regards to its size and perhaps even try to see one in person before buying.

[Victor Boesen]

42 minutes ago, Alan White said:

Victor, could you perhaps negotiate the Dob living with your Grandparents?
 

That's definitely not a bad idea!! It'd be good to have a "permanent" scope at their house, but I have mixed feelings about having my dob stored in their house with regards to space and etc. After all they're both above 70 and, not to discriminate anyone with the same age on here, not at their same physical shape as they've been before. I will think about this since it's definitely not a bad idea!

Victor

[R26 oldtimer]

I have left my 10" dob at my in-laws, who live at a very dark mountain village. Sometimes I take my astrophotography setup there and use the dob while imaging, or travel light just to find a ready to go dob with a couple of eyepieces already there. They do take their glimpse of the universe occasionally, even though they knew nothing about astronomy.

[Victor Boesen]

1 minute ago, R26 oldtimer said:

I have left my 10" dob at my in-laws, who live at a very dark mountain village. Sometimes I take my astrophotography setup there and use the dob while imaging, or travel light just to find a ready to go dob with a couple of eyepieces already there. They do take their glimpse of the universe occasionally, even though they knew nothing about astronomy.

It'd mean that I would never have to bring a telescope when visiting, unless I want to do imaging or something else as you say yourself, and that would be nice.

[RobertI]

I think you've had some great advice there Victor - it sounds like you're closer to your answer. I certainly haven't had the variety of telescopes of many people here, but my recent experience of refractors is that an F7 100mm frac is much easier to use than a F10 equivalent, less wobble in wind, less wobble when focussing at high power, less need to have a really tall tripod becasue the tube is shorter, and easier to get wider fields whilst still allowing high power. I know the SW 100ED is F9 so may not be as bad as F10 but it's still long.  For portable solar system the Mak 127 does sound like a great choice and nice complement to the 72ED, and a modest mount could accomodate both.    

[Victor Boesen]

16 minutes ago, RobertI said:

I think you've had some great advice there Victor - it sounds like you're closer to your answer. I certainly haven't had the variety of telescopes of many people here, but my recent experience of refractors is that an F7 100mm frac is much easier to use than a F10 equivalent, less wobble in wind, less wobble when focussing at high power, less need to have a really tall tripod becasue the tube is shorter, and easier to get wider fields whilst still allowing high power. I know the SW 100ED is F9 so may not be as bad as F10 but it's still long.  For portable solar system the Mak 127 does sound like a great choice and nice complement to the 72ED, and a modest mount could accomodate both.    

I've gotten more than great advice;)) I've started looking at some different scopes that could suit my current situation, and I'm thinking a 100mm f7-f9 refractor could be the final choice:)

[mikeDnight]

As Rob mentioned, an F7 102mm ED would be easier to carry around, especially if it had a retractable dew shield as many do. And they are not too expensive, relatively speaking.  At around F7 you'd have the best of both worlds, with high power planetary and wide rich field deep sky views too. With your ES 24mm 82° eyepiece you'll be in astro heaven with eyes filled with diamond dust as you sweep along the milkyway. While at high power, the spring Moon will leave you speechless!

Edited September 20, 2020 by mikeDnight

[Victor Boesen]

1 minute ago, mikeDnight said:

As Rob mentioned, an F7 102mm ED would be easier to carry around, especially if it had a retractable dew shield as many do. And they are not too expensive, relatively speaking.  At around F7 you'd have the best of both worlds, with high power planetary and wide rich field deep sky views too. With your ES 24mm 82° eyepiece you'll be in astro heaven with eyes filled with diamond dust as you sweep along the milkyway. 

I've seen some people using the Altair Starwave 102mm F7. Seems like a decent choice, but I haven't been able to find many reports/reviews with regards to quality. Someone did mention that it had a sliding dew shield which would add to the portability

[mikeDnight]

Here are a couple of ED's that might be of interest. You'll only need a doublet ED for visual observing, but the two attached use different glasses, with the second being FPL53 coupled with lanthanum, so very close to a true fluorite apo.

[Victor Boesen]

14 minutes ago, mikeDnight said:

Here are a couple of ED's that might be of interest. You'll only need a doublet ED for visual observing, but the two attached use different glasses, with the second being FPL53 coupled with lanthanum, so very close to a true fluorite apo.

They both look very interesting... The one with lanthanum optics is especially interesting, but I'm afraid I might start to push the upper limits of my budget since I will probably also need a new mount and perhaps even a 2" diagonal to replace my current 1.25" Takahashi prism diagonal....

I'll do more research:)) But thank you very much for the recommendations! They're definitely worth considering.

[Victor Boesen]

I'm still leaning towards the Evostar 100 based on its price, included case and proved performance. The competitor is mostly the TS 102mm F7(lanthan optics) or the Altair Starwave 102ED-R which both have perhaps better build quality, better focusers, sliding/removable dewshield and a shorte focal length for a wider FOV, although they're more pricey and no case or accessories are included. I've tried contacting my friend who owns an Evostar 100ED so I can get his opinion on its size, focuser and etc. It'd be sad if the weight of my 2" 24mm 82 degree eyepiece was too much for it!!

I'll keep this thread updated:)

Victor

[Victor Boesen]

I've eventually come to what seems like could be the final decision... I've had a thought about @Alan White's idea of storing the dob permanently at my grandparents, but come to the conclusion that it would be slightly disrespectful to them because of their age. Instead I've basically decided that I'll go for the 100ED, and I am lucky to have a local vendor in Denmark who, according to their website, still have them in stock. This does mean I pay a little more than on FLO, but I'll have to remember to support the local shops around here;))

Since I know @mikeDnight is a fan of the AZ4 mount I've decided an AZ4 mount on a stainless steel would seem like a good solution. I've given the alt/az gti a thought because of its tracking capability but I worry it won't be able to carry the scope properly and that I won't use the tracking/goto capability much since alignment would also take some time to do, which would ruin the entire "grab and go/short session" setup that I was ideally looking for.
I'm also currently thinking about adding the Baader BBHHS diagonal with a 2" click lock( + 2"-1.25" adapter) and 2" nosepiece to use with both my fracs and sell my current Takahashi 1.25" diagonal.

I'd love if I could enjoy the frac on Mars during this opposition, but I just have to verify things before I purchase everything such as compatibility between my ES 82 degree eyepieces, the diagonal and etc!!

Victor

[Davey-T]

7 minutes ago, Victor Boesen said:

storing the dob permanently at my grandparents, but come to the conclusion that it would be slightly disrespectful to them because of their age

I'm  old but you can store it here I don't mind 😂

Dave

[mikeDnight]

44 minutes ago, Victor Boesen said:

I've eventually come to what seems like could be the final decision... I've had a thought about @Alan White's idea of storing the dob permanently at my grandparents, but come to the conclusion that it would be slightly disrespectful to them because of their age. Instead I've basically decided that I'll go for the 100ED, and I am lucky to have a local vendor in Denmark who, according to their website, still have them in stock. This does mean I pay a little more than on FLO, but I'll have to remember to support the local shops around here;))

Since I know @mikeDnight is a fan of the AZ4 mount I've decided an AZ4 mount on a stainless steel would seem like a good solution. I've given the alt/az gti a thought because of its tracking capability but I worry it won't be able to carry the scope properly and that I won't use the tracking/goto capability much since alignment would also take some time to do, which would ruin the entire "grab and go/short session" setup that I was ideally looking for.
I'm also currently thinking about adding the Baader BBHHS diagonal with a 2" click lock( + 2"-1.25" adapter) and 2" nosepiece to use with both my fracs and sell my current Takahashi 1.25" diagonal.

I'd love if I could enjoy the frac on Mars during this opposition, but I just have to verify things before I purchase everything such as compatibility between my ES 82 degree eyepieces, the diagonal and etc!!

Victor

It all sounds good to me Victor. The 100ED comes with a 2" diagonal I believe, so you might want to try that out first be for buying the Baader. The AZ4 comes with a leaver handle that you probably won't need, but the threaded hole can be used for a second locking bolt for added security.  I'm pretty sure your eyepieces will work well with the SW 100ED but ask your vendor to be certain. You could ask the vendor if they have a price match offer, you never know, they may match the FLO price.

Edited September 21, 2020 by mikeDnight

[Victor Boesen]

1 hour ago, mikeDnight said:

It all sounds good to me Victor. The 100ED comes with a 2" diagonal I believe, so you might want to try that out first be for buying the Baader. The AZ4 comes with a leaver handle that you probably won't need, but the threaded hole can be used for a second locking bolt for added security.  I'm pretty sure your eyepieces will work well with the SW 100ED but ask your vendor to be certain. You could ask the vendor if they have a price match offer, you never know, they may match the FLO price.

You're right about the included diagonal, and perhaps I should save my money now and upgrade it in the future if I find the need to:) I'll try to give my vendor a call tomorrow with regards to the price. Although I don't expect them to sell at the same price as FLO It'd be nice to save some money!!

Very useful information about the AZ4... Thanks for mentioning;)

[johninderby]

One thing to keep in mind is that the focuser on the ED100 is not exactly the best and many upgrade to a better one such as the Baader Steeltrack or Moonlite. Perhaps a used Equinox100 if you could find one could be a good choice. Same optics but much nicer with a better focuser, retractable dewshield etc.