Another TV...

[Naemeth]

I did it again, ordered another TV plossl, this time it's the 20mm. The seller of the 11mm on ABS hasn't emailed me back, so when an opportunity came to get one I snapped it up. In comparison to the LV 18mm, it gives 3x less magnification and a slightly wider view (1.54 degrees vs 1.38), but those short FL gaps will come in handy when I upgrade to a scope with more FL. It should also be interesting to compare the two, but I suspect performance will be very close indeed.

Now I just have the 11mm, 15mm, 25mm and 32mm to add of the TV plossls and my 'collection' will be complete (not going to bother with the 40mm, and the 55mm is 2").

[John]

Nice Jonathan

I would not worry about the 40mm - it's not par-focal with the others and, like all 1.25" 40mm's is limited to a 43 degree AFoV. You don't see any more sky really than with the 32mm.

If you get a 2.5x Powermate you will also have 4.4mm, 6mm, 8mm, 10mm and 12.8mm TV plossls as well - a very comprehensive and capable eyepiece set that could last a lifetime.

[Naemeth]

As it turns out, John, I'll be adding another two very soon: the 15mm and the 32mm .

I wasn't aware that the 1.25" TV plossls were par-focal, but it certainly sounds like something useful to have! They do seem to need quite a lot of out-focus, a good bit more than the LVs which are already quite far out.

I'm not sure about a powermate, I didn't particularly like using my Tal x2 barlow. I might give the barlow a second chance though.

[John]

The Powermates are expensive but, apart from the magnification, you just don't know they are there. The TAL 2x is a decent budget barlow but the Powermates are in a different league to be honest.

[Pig]

I will invest in aX2 powermate after my next purchase, that should set me up for quite a while

[DaveJFT]

I will invest in aX2 powermate after my next purchase, that should set me up for quite a while

I've got one if you'd like to try it out next time we meet.

Dave

Sent from my ASUS Transformer Pad TF700T using Tapatalk HD

[Pig]

Dave that would be great I would like to give it a go , According to the met office this Saturday is going to be clear, I might go over to the dark site. Is that an option for you ? or even somewhere more local.

[DaveJFT]

If I can I'd certainly like to try out my new mount, though I think I may have a problem with it - http://stargazerslounge.com/index.php?/topic/189177-Celestron-SLT-mount-slew-limit-setup#entry1973887.

Even if I can't make it, you're welcome to pick the TV up on your way by to try it out.

Sent from my Nexus 4 using Tapatalk 2

[AlexB67]

I will invest in aX2 powermate after my next purchase, that should set me up for quite a while

I would like one of those ... at some stage. So far all I could find in the powermates is the 2.5 times in 1.25 ", does a 2x exist ? I see they do 2x for a 2 inch, but not sure for my Heritage a heavy mounting with lots of adapter is a good plan, even if that is possible.

Anyhow with the 2.5 times it is not as if the gaps would fill in that badly, but I had better decide and plan appropriately before I start buying extras, so far I had not really considered it and always kept the 2x figure in my head.

On the other hand by the time I buy such a an expensive addon, the bigger DOB may well be a priority before then anyway. Plan so far is that probably I'll buy one or two eyepieces more at most, and buy them in such a way that they'll work well out nicely across the range in an 8 inch DOB. Or should I really be thinking a 10 inch and wait and save a bit more .... decisions, decisions, decisions ...

[Naemeth]

I would like one of those ... at some stage. So far all I could find in the powermates is the 2.5 times in 1.25 ", does a 2x exist ? I see they do 2x for a 2 inch, but not sure for my Heritage a heavy mounting with lots of adapter is a good plan, even if that is possible.

Anyhow with the 2.5 times it is not as if the gaps would fill in that badly, but I had better decide and plan appropriately before I start buying extras, so far I had not really considered it and always kept the 2x figure in my head.

On the other hand by the time I buy such a an expensive addon, the bigger DOB may well be a priority before then anyway. Plan so far is that probably I'll buy one or two eyepieces more at most, and buy them in such a way that they'll work well out nicely across the range in an 8 inch DOB. Or should I really be thinking a 10 inch and wait and save a bit more .... decisions, decisions, decisions ...

Get a 200P . It really isn't worth getting a 2" to 1.25" to use the powermate on the Heritage, that combination alone would sag the plastic connecting the focuser to the cage at the top, let alone putting an eyepiece in .

Edit: Just looked up the figures, the TV 2.5x powermate is 204g. I've worked out about the maximum the Heritage focuser can take is about 160g-170g.

[AlexB67]

Thx, My gut feeling was as you said it, and to be spending a lot more on the eyepieces and add-ons in general. I've always had that plan to invest in more aperture instead as a higher priority before that anyway, seeing my interest in DSO hunting.

[Naemeth]

Thx, My gut feeling was as you said it, and to be spending a lot more on the eyepieces and add-ons in general. I've always had that plan to invest in more aperture instead as a higher priority before that anyway, seeing my interest in DSO hunting.

I'm going the other way - getting my good quality (and light eyepieces) now, getting a smaller imaging scope / travel scope (ED80), then going for an increase in aperture (C8 / C9.25), then some imaging (HEQ-5 mount ).

[michael.h.f.wilkinson]

That a nice collection of black and green you are building up.

[Naemeth]

That a nice collection of black and green you are building up.

I'm seriously thinking I'll need another case soon. There are 13 eyepieces in it at the moment :Envy:.

[michael.h.f.wilkinson]

Maybe first get rid of the unused ones

[Naemeth]

Maybe first get rid of the unused ones

Good point

[AlexB67]

I'm going the other way - getting my good quality (and light eyepieces) now, getting a smaller imaging scope / travel scope (ED80), then going for an increase in aperture (C8 / C9.25), then some imaging (HEQ-5 mount ).

I can see that from you sig but yep, I can see arguments for both in a way. It particularly struck me that eyepieces can start eating up cash very quickly. Before I started this hobby my guess would have been that the telescope would be the main cost, but now I know this is not the case.

When I consider how much quality eyepiece I get per pound versus DOB aperture per pound, and the fact that eyepieces are not going to run away that I already have, so yeah, at the moment my aperture temptation seems a stronger one to go for sooner rather than later.

That being said, I love the heritage for its grab and go nature and quick setup, so now that I have it I will not part with it when I buy a bigger DOB, it is more a question of 8 or 10 inch as a decent upgrade next time. There is still so much to see and do, so much joy to be had with the heritage. The bigger dob can wait anyway. so I'll save for that. I don't see it arriving until well into next year. In the back of my mind the 10 inch is a tempter even if it means waiting and saving a bit longer, as it is not as important to be a grab and go as well, seeing I already got myself a nice grab and go

[Moonshane]

The TV plossls are superb value for money. They are really as good as anything else I have tried other then field of view and with the shorter ones, eye relief. They are light, well built and optically brilliant. I also have a collection of them (11m, 15mm, 20mm, 25mm and 32mm) and have not paid more than £60 for any of them and some substantially less. this despite having a 26mm nagler and 13mm ethos.

[Mr Bond]

I have a couple of 32mm TV Plossls. Superb. Great for use in a binoviewer, but the field stop is just fuzzy. Very nearly full field.

Razor sharp though.

[John]

Theres a lot of used Radians about at the moment, presumably as folks decide to step up to Delos with the 15% discount.

Great eyepieces for around £100 apiece I reckon

[michael.h.f.wilkinson]

I have seen the glut of Radians on ABS-UK too. Very good deals to be had, methinks

[Naemeth]

I had considered the Radians, but I think they are far too heavy for this scope at about 330g.

A lot of thought had to go into eyepiece choices for this scope, and let this be a warning to anyone else wanting to upgrade their eyepieces in this scope. In terms of premium EPs, you are limited to Plossls, NLVs / LVs, Monocentrics and Abbe-Orthos - anything less than about 180g.

[John]

Thats a very good point Jonathan. No point in putting too much strain on the focuser.

[Naemeth]

Thats a very good point Jonathan. No point in putting too much strain on the focuser.

I wish that whole area had been redesigned . It's only a small bit of plastic that holds the helical focuser at the right distance and directly in line with the secondary mirror. With a heavy eyepiece, this plastic sags, so it would result in the optical path being misaligned.