What is the BEST 200-300mm telescope / lens?

[rorymultistorey]

Thx  for taking the time to read this post. I'm trying to figure out what wide field 200 - 300 mm scope to get...  I want the best possible although I'm not very keen - who is - on breaking through the £1000 barrier. I actually have one 255mm scope that I'm very happy with. A tak fs60cb paired with a borg 0.7x 7870  reducer bringing it to a nice F4.1 But I want another for dual rig imaging. I tried dual rig imaging out last saturday  from a field nr Basingstoke with the Farnham nights crew  - it was fun - results below. I used the Tak for luminance  and a Tokina 300mm f2.8 lens for RGB. While the Tokina performs as well as any 300mm lens (its as good as the canon 300mm L series I once owned) for astrophotography the stars are still a bit too bloaty and the CA is a bit of an issue. So I want to replace the Tokina with something else... Maybe a Borg?  If so which one? Are there any other options?

Below are images from last saturday... I'm also experimenting with intagrams tiltshift filter - please let me know if you hate the tiltshift before I post on astrobin !!!!

[vlaiv]

Would 360mm be ok?

TS 80mm F/6 paired with Riccardi x0.75 FF/FR should give you pin point stars and run at F/4.5 for 360mm FL

Then there is this:

https://www.teleskop-express.de/shop/product_info.php/info/p9249_TS-Optics-Photoline-72-mm-f-5-5-FPL53-Apo---2--R-P-Focuser.html

Can't say about quality of it since I neither seen one nor read about it. Again pair it with Riccardi FF/FR and you will have very fast F/4.16 300mm imaging scope.

Do however pay attention that Riccardi FF/FR needs quite a bit of backfocus. I think that TS80 F/6 with 2.5" focuser can handle it (170mm back focus), but not sure about second option.

[rorymultistorey]

Thank you.  Much appreciated.  I'd not thought of using the riccardi reducer I'll look into it right now.  Excellent.