johnrt

Thank you for all the comments!

The truly amazing thing about thing about the 6"RC is that it doesn't get more exposure as an imaging scope and not more people have caught on, perhaps Chris is right and the 8" version is preferred. I have thought about upgrading to the 8" RC but then what would be the point, especially after the weather since the end of May in the UK has been terrible ???

I have the latter part of last year and all of this year so far honing my LRGB skills, which is a dark art all in itself, but as they say with capturing the data - rubbish in, rubbish out!

PS. I last collimated this scope in Summer 2014 and it's still bang on!

Good luck Ian, looking forward to seeing some images from the RC.

Interesting thoughts to consider ideed Olly, you've just left me wondering where to mount my 2" IDAS if I remove the CCDT67 (it currently screws in to the front of it). I do see where you are coming from, but I also admit that I do like the slightly wider framing in the shots above, there's a background fuzzy just creeping in to the edge of the frame in nearly all of them  

BUT! I would be fibbing if I said I hadn't checked out numerous targets and rejected them as I didn't quite have the focal length to do them justice, these are the ones that got through!

John do you ever use your system at native FL or always with the CCDT67?

Always with the reducer Steve, f/9 would be sooooooo slooooooooooowwwwwww!!!!

Thanks Ian, so long as you’re prepared you won’t regret buying either the 6 or 8” RC.

Just on the subject of focus drift - I used to have a carbon 80mm triplet refractor and found that the scope contracted a large amount moving the focus point as the temp dropped, it is as Sara says, a problem if you are manual focusing. However with the metal tube of the 6” RC I find there is no focus adjustment needed at all, just focus at the start of the night and forget about it. Perhaps this is due to the carbon body that just expands and contracts more than the standard metal tube?

The reducer that is commonly used with the 6, 8 & 10” RC’s is the Astrophysics CCDT67, it works brilliantly. I’ll also agree with Sara that the feathertouch is a must have.

Have you now sold your 8” RC Sara?

This thread is rather old as hasn’t got any recent pics from the 6” RC in it, so here’s a couple from galaxy season earlier this year (before the light nights ruined the fun).

John.

What about periscope for smart phone users?

What can I say about this? I just don't know. I really don't. Stupidly good. Absolutely ridiculously good.

johnrt & kirkster501 - I see that you're both using the Atik 460. Aside from the 2" IDAS filter, are your other filters 1.25"?

Do you find any issues with vignetting on the CCD image using the 1.25" filters?

I have a similar setup, but I use a DSLR at the moment; I'm seriously considering upgrading to the Atik. With the DSLR, all filters are 2" to avoid vignetting, but it is my understanding this is less of an issue with the smaller chips of CCDs such as the 460.

Thanks,

joe

The 460ex is fine with 1.25" filters. You can even get away with them on the larger 383l if they are kept close to the camera chip.

very interesting thread.

John - I see on your website that you're currently using an IDAS LP2 filter. Have you placed this in your filter wheel? (or is it placed ahead of the filter wheel and therefore used in all images?)

Thanks,

joe

I have the 2" IDAS which sits infront of the filter wheel and I leave in place permanently - even for narrowband. The IDAS has over 95% transmission for Ha so I'm only missing out on an insignificant amount of photons by leaving it on all the time.

Doug, I agree the 6"RC is a great scope, if you're prepared to get stuck in to it. My latest upgrade for it is in the post from that America - a Losmandy dovetail for mounting the OTA to my AZEQ6. http://www.deepspaceproducts.com/d-series-dovetail-plate-astro-tech-orion-rc-6-quot-_8_4234_8580.html

There have been many images with this scope since I last updated this thread, and rather than re-post them all here as many were posted individually in DSO imaging section, you can find them all on my webpage if your interested  https://cloudedout.squarespace.com/blog/

I have nothing to say about this other than stupidly good. You can get lost amongst the dust and clusters in there for hours.

I leave mine in all the time, in front of LRGB, Ha and OIII. Makes not a jot of difference.

I've emailed FLO to ask if they will consider adding them as they already stock Astrozap dew shields.

One of these might help too, but I can't seem to find anywhere that sells them in the UK

https://www.astronomics.com/astrozap-flexible-black-plastic-6-inch-astro-tech-at6rc_p19266.aspx

To be honest I haven't found dew to be an issue with my RC. I have used it on some pretty damp and cold evenings, and while my ST80 is fogged up the RC stays nice and clear. I would suggest a quick blast from a hair drier if you don't want to install the secondary mirror heater (which looks rather nifty btw) would be good enough to keep it all clear.

John

By the way where abouts in Kent are you Magnum?

I can give you a full list of the equipment I use, but that does not make a definitive list and price. You might get items 2nd hand where I purchased new, you could opt for a different camera, a DSLR for example instead of a mono CCD and filters, Just because I did it this way doesn't make it right, there's more than one way to skin a cat.

Here is a list and approximate cost of the gear I use.

Mount : HEQ5 Pro Synscan £760

Imaging Scope : Altair Astro 6" RC £400

Guide Scope : Skywatcher ST80 £90

Imaging camera : Atik 314l+ £1100

Guide camera : QHY5 £199

Light Pollution filter : IDAS LP2 £170

Reducer : CCDT67 telecompressor £180

Filterwheel & LRGB filters : £300

Pixinsight software : £180

PHD software : FREEEE!!!!

And more recently I've also upgraded to a 3nm Ha filter too - £359

So was this by removing the rear mirror cell from the OTA leaving the front spider assembly with the secondary still within the scope?

No I removed both, the mirror cells are pretty sturdy things even out of the OTA.

Whats is like to collimate after having the thing in bits?

Very easy, primary needed no adjustment whatsoever and the secondary just a tweak.

Wonder if these issues are unique to the 6" version John? My Carbon Fibre RC8 *seems* OK. That said, I have not been as exactlng as you (yet)......

Only one way to find out!

I also found the primary mirror had a bevelled edge to it, cut at about 45 degrees, and with a textured silver & shiny finish, there were also fines of silver material floating about. I took this opportunity of having the scope in bits to get rid of the excess material and blacken the bevelled edge with a sharpie. Reflective surfaces inside the OTA bar the face of the primary and secondary aren't going to help anything.

So it would seem there is also a third area to check if you choose a 6" RC on top of the primary mirror & focuser.

I had the OTA in bits again the other day as I still saw some (although much reduced) drift in the fov over time, despite the tightening up of the primary mirror. I removed the front cell and discovered that the secondary mirror also needs checking as it was loose in it's holder, it is again a simple fix, just tighten up the compression ring, re-assemble and check the collimation.

Why don't you have a read through this thread, it is my experiences of owning a 6" RC and quite a few of the images I have have produced with it.

John

Has anyone thought about replacing the metal tube with a carbon one on this 6" RC?

What is your reasoning for this, minimise weight, stiffen tube?

Damn those pics make me want to get into AP...

It's a dark and slippery road, and one that is guaranteed to make you poor!

Some good info there, and some stunning images...... Has anyone tried one of these 6" RC's with a DSLR yet? I will soon be buying another imaging scope and quite like the look of these.

Gaz

Hi Gary,

Yes there are quite a few using it with a DSLR, it's the same scope as the GSO and Astro Tech 6" RC so you can turn up quite a few images with a google search.

Would you think this scope can perform well enough under light polluted skies?

Yes, with the reducer it it f/6, not the fastest in the world but useable. My imaging location is certainly not what I would call dark, but I would see no reason it would still not perform well even under poor skies.