80ED vs 150PDS

[Ags]

the usual recommendation to a newbie imager like me is to start with an ED80, but is that really good advice?

For example, the 150PDS has only slightly longer focal length, while at F5 the newt exposes an image twice as fast as the refractor. So for a given exposure, the newt should show less tracking error. I think even if the 0.8 reducer is added to equation, the newt is still slightly ahead.

Then there is the issue of raw speed: using an uncooled DSLR, exposure times are limited, so you can grab more photons with less noise with the newt.

Regarding resolution, the newt has twice the resolution of the ED80 which must help a bit with DSOs and would help with lunar and planetary imaging.

[Earl]

The 80ed will be easier to guide easier to use as there is no collimation and lighter (not 100% on that however).

So for starting off the 80ED has far less faffing.

but its not really going to be a Planetary and luna imaging scope.

still start off with the 80ED convert the finder into a finder guider, and see how you get on with that first the review your options later.

[Ags]

I don't Initially have a budget for guiding, so being unguided speed is even more important... Also, i have bad light pollution to contend with so I suppose narrowband imaging is the best bet in the longer term, again calling for speed.

When it comes to guiding I already have an ST80 so I would look to using that.

What you're saying is reasonable, but my heart's currently set on a VX6 scope with 1/10 pv... No worries, I'll soon change my mind once more :-(

[RikM]

I thought much the same as you, and wanted to use the scope for visual observation as well. I went with the 150P (no DS version at the time) and for me, that was the right choice. Much cheaper than the 80ED too.

I do find my images are not as sharp and contrasty as seen with refractors. I put this down to me rather than the scope. I don't think I have the collimation quite perfect yet, but a cats eye kit will sort that out.

Starting with a refractor removes this issue and they cool much quicker, have a wider field etc etc. There are a lot of reasons why and ED80 is the best first imaging scope. But it is certainly not the only option if you are willing to put in a little effort.

[Ags]

Rik, you have an impressive set of pics. Thet look sharp to me. Were they all shot with your Canon? I assume you've modded your camera?

[RikM]

Thanks.

All my images were shot with unmodified Canon 1000D or 300D DSLRs. I use APT software to control the camera from my lappy. I was going to get the 1000D modified, but I think I am going to go the CCD route instead.

[Ags]

Those pics are awesome for an unmodded camera.

I think I will go for the VX6. I want it to be the last scope I buy for a couple of years.

[ollypenrice]

Your thinking is not wrong in theory. However, imaging is difficult and small refractors make it easier. It might be the case that, by the time you have the Newt ready to image, you would have had an hour's data in the can from the refractor. Then there's a gust of wind... etc. It's a hard decision and a lot depends on how adept you are at faffing (a wise choice of word from Earl above!)

I would choose the refractor but I'm not blind to the counter argument. With two or three rigs on the go, sometimes, I like NO FAFFING!!!

Olly

[FrankieValley]

Toss a coin! My advice would be to start with the reflector for the reasons you give and then buy a refractor in the future..... or do it the other way round. Either way, you won't be disappointed. They are both great scopes and essentially you cannot make 'a wrong decision' - either is the right decision :-)

[riklaunim]

Short refractor is easier to start with - less fragile to wind, guiding/tracking errors and alike. Fast Newtonians - are fast but require good colimation / focus and are noticeably more fragile to wind, balance...

I made some images with a C8 and C11 and big resolution is usable only to few objects like planetary nebulae. My refractor can kick in and even with small mono I can fit most if not all available DS objects available from my balcony

So it's hard to say which to choose