Reflector Telescope for Astrophotography

[PeterBolt]

I was just wondering if there is anyone else who is using a reflector telescope for astrophotography?

[Carastro]

I have used one in the past.  I have used Skywatcher 200PDS, 150P and 130PDS Newtonians.  They were great but I found the 200PDS too big, and the 130PDS was great for a long time until I messed up the collimation good and proper and decided to go back to a refractor. 

Carole 

[DaveS]

I briefly used a 130P-DS a few years ago, sold it and bought a TS Photoline 130mm f/7 triplet apo.

Currently getting a 12" ODK into service, which is a little bit bigger than a 130P-DS.

Will report when I get first light.

[Gina]

I have a Skywatcher MN190 but not used it recently.

[philjdowns]

I've got an Orion Astrograph 200mm, just the one scope, almost got everything I'll need ?  
Got the primary out at the moment, building a dew heater.

[PeterBolt]

Looks great, do you use a coma corrector?  Any recommendations for an F5?

[philjdowns]

@petedevon Hi, yes I have a "SkyWatcher F4 Aplanatic Super Coma Corrector" it's optimised for f4 which matches my OTA.

Getting started I thought I could get by without for a while but even before I had my imaging train fully completed, I was seeing some truly horrible coma which was also causing me problems focussing, and only the centre 1/5 of the image was even passable. So jumped straight for the Aplanatic. There are cheaper ones out there but you get what you pay for. Stars are now nice little points so it's doing it's job well, as far as I can tell at this stage.

It was a bit of a pain getting the correct back focus (the distance from the camera side of the corrector and the imaging sensor) taking into account that you need to add approximately 1/3 the thickness of any optical elements in between (all my filters are 2mm so I needed 25.66mm) I've managed to get to 25.7mm so only 0.04mm out.

I've only got an f4 and don't know what other issues you'd get if you used this on an f5, but there are f5 coma correctors out there. There doesn't seem to be many of us Newt people on here at the moment, but if anyone else has any thoughts please chip in.

Phil.       

[PeterBolt]

 

Thank you for the helpful information. I have seen the skywatcher 0.9x corrector that is within my budget and seems to suggest will work well with F5.  I might give it a go when it is back in stock. Do you think the issue in the attached photo is coma or could there be any other issue? I have the standard rack and pinion focuser which I find hard to collimate due to the play in the mechanism.  I am looking to upgrade this to a crayford style in future again when they are back in stock...

[DaveS]

Photo of my ODK12 in the obsy, now waiting for PA and first light.

This is set up for galaxies, as the FoV is a bit tight for most emission nebulae, even with the G3 16200 camera.

[Stub Mandrel]

It's hard not to recommend the 130P-DS, used with a coma corrector it is awesome.

[Jkulin]

Hi Pete, I use a 10" RC reflector and love it, I do really like good sharp refraction spikes, no need for a Coma corrector with an RC or a reducer, I am just organiser a 10" Newt to be rebuilt as well.

I do have some refractors, but too busy going close up over the last couple of years.

[TerryMcK]

I’ve heard a lot of good reports and seen some wonderful images taken with the Skywatcher 130PDS.

Fairly light in mass, well made, reasonably priced and not a boat sail in the wind. I prefer to use refractors myself but if was on a budget would try the 130PDS for sure.

[PeterBolt]

I am stil using my 8" Helios which I believe changed into Skywatcher.  I am very attached to it so I can't see myself changing anytime soon ? I have ordered a new focuser and coma corrector but not sure when it will arrive!  Still something to look forward to trying.  

[paulgrover68]

I use a Skywatcher 200PDS with the f5 coma corrector. I love it. Good sharp stars right across the frame. Focuser is great too.  It is bulky and hard to balance.

More recently I have been using my 72EDF - mainly because I'm pointing at bigger things. I do intend to point the 200 at M42 and the Horsehead once I complete my wider field images.

I can see myself using a longer focal length refractor at some point in future - but I'll probably still use my 200 from time to time, because I like it.

[PeterBolt]

@paulgrover68

That's great, do you have the skywatcher coma corrector? 

I think the PDS has the focuser that I have also ordered so it's good hear that you rate it highly

[paulgrover68]

@petedevon Yeah - I have skywatcher one. It reduces the focal length by 0.9 so you gain a litte more field. Baader also which does not reduce FL. I can vouch for the Skywatcher one and have have heard good things about the Baader.

[PeterBolt]

@paulgrover68 that's great thanks I think I will wait for the skywatcher?