What have you seen in a 5" Refractor, that you've not seen in an 8" newt?

[Mr Spock]

Seeing the pup is all about seeing conditions. If you can get Sirius as an airy disk without fuzziness or twinkling then your chances of seeing the pup increase. I find smaller scopes better as Sirius is too bright in larger ones and more prone to fuzziness. My best views have been with the 100mm.

[Space Hopper]

@Flame Nebula Did you say you were near Notts ? I'm in Derby so a similar latitude, and its always going to be difficult to see something like this at 53ºNorth with out dodgy seeing conditions sadly

[Flame Nebula]

1 hour ago, Space Hopper said:

@Flame Nebula Did you say you were near Notts ? I'm in Derby so a similar latitude, and its always going to be difficult to see something like this at 53ºNorth with out dodgy seeing conditions sadly

Hi, yes near Nottingham. 

Indeed, my previous attempts were like looking at a flare. But, I'm up for a challenge. After all it's the closest example of a white dwarf. 

[Flame Nebula]

1 hour ago, Mr Spock said:

Seeing the pup is all about seeing conditions. If you can get Sirius as an airy disk without fuzziness or twinkling then your chances of seeing the pup increase. I find smaller scopes better as Sirius is too bright in larger ones and more prone to fuzziness. My best views have been with the 100mm.

Indeed, part of the reason I'd like a 5" frac in the armoury. Might be worth the sub aperture approach too. 

[wesdon1]

17 hours ago, Flame Nebula said:

Thanks Wes, 

I'll probably get the mount new, as it really is critically important there are no issues with it, as I intend to also do DSO AP, which will need very accurate tracking, especially if I move up from frac to newt. But, if I see a used 200pds which has been modded, and I know many people do, and it's cheaper than new, it would be hard to resist. The only pain is travelling several hundred miles, only to find the mirror has, shall we say, seen better days. 

However, I think for the frac, you're totally right. In fact I bought my 80ed for £330 off Ebay and it's perfect! Same with the 127mm mak, £120 off Ebay. Nothing wrong with it. However, I would not buy more expensive stuff from there. I did see a £700 frac being sold near where my parents live in Wales, but not ready to buy yet. But, it shows they're out there at that price. 

With gear like the asiair, being electronic and again absolutely critical part of dso AP, I'd probably buy new. 

But, case by case I think. 👍

@Flame Nebula yes I totally see your reasoning my friend. I look forward to seeing how you get on with AP in coming months! I'm only 15'ish months into AP so I still have lots to learn. I have done visual astro for some 7-8 years I think. I absolutely love the hobby! I just wish our UK weather would be kinder to us all! LOL

[Piero]

“What have you seen in a 5" Refractor, that you've not seen in an 8" newt?”

 

I would do solar observing with a refractor.

Apart from that, imagination..

[Mr Spock]

I would add to that - my 120mm achro with continuum filter is incredibly sharp on the sun. Knocks the spots (groan) off the 4" by a considerable margin. I don't really fancy a reflector with solar film, I don't believe its going to be sharp enough.

[John]

11 minutes ago, Mr Spock said:

I would add to that - my 120mm achro with continuum filter is incredibly sharp on the sun. Knocks the spots (groan) off the 4" by a considerable margin. I don't really fancy a reflector with solar film, I don't believe its going to be sharp enough.

Yours sounds a good 120. Many (most ?) of the chinese achromats have varying degrees of spherical aberration which scrubs the edge of their higher resolution performance. The Chromacor correctors were about correcting that SA as much as they were about correcting CA in such scopes.

The Chromacors were aimed at the 120 F/8.3 and 150 F/8 chinese doublets produced by Synta. 

 

 

[Mr Spock]

5 minutes ago, John said:

Yours sounds a good 120. Many (most ?) of the chinese achromats have varying degrees of spherical aberration which scrubs the edge of their higher resolution performance. The Chromacor correctors were about correcting that SA as much as they were about correcting CA in such scopes.

The Chromacors were aimed at the 120 F/8.3 and 150 F/8 chinese doublets produced by Synta.

I always wanted a Chromacor for it. It's a fine, well corrected, scope. Pretty good on doubles with minimal CA. Very noticeable on planets though. The continuum is such a narrow band it removes all of that and just leaves a clean, sharp image. It's one of the original Helios scopes - can't remember how long I've had it.

[John]

1 hour ago, Mr Spock said:

I always wanted a Chromacor for it. It's a fine, well corrected, scope. Pretty good on doubles with minimal CA. Very noticeable on planets though. The continuum is such a narrow band it removes all of that and just leaves a clean, sharp image. It's one of the original Helios scopes - can't remember how long I've had it.

I wonder if those older ones are slightly better than the more recent ones ?

I've owned 4 of the 150 F/8's, 2 Skywatcher ones, 1 Konus (yellow !) and 1 Helios. I recall the older ones, the Helios and the Konus, were the best optically.