Best flattener for my TS 80/480mm F/6 Triplet APO Refractor

[Astronut1982]

I've just managed to pick up one of these beauties S/H & I'm looking for a bit of advice with regards to which flattener I should buy to achieve a perfectly flat field.

I understand that the flattener has to be a certain distance from the camera sensor but I'm not sure at all how this is worked out & wondered if anyone here would be able to advise me on how to do this?

Also, which flattener is best to buy, the two that I was looking at were these:-

http://www.365astronomy.com/ts-universal-2inch-field-flattener-for-refractors-from-f5-to-f8-p-3080.html

http://www.firstlightoptics.com/reducersflatteners/hotech-sca-field-flattener.html

Would anyone be able to advise which of these would be best or if there is another out there which would suit me better, my budget would be around the £200 - £250 mark.

Thanks in advance,

Jeff

[Andyfx]

I have the TS IND70 which is F6 and 420mm FL. I have tried so many flatteners trying to get a perfectly flat field with my Canon 1100D and only one did the trick....

I found the TS Flattener absolute rubbish with dslr and colour correction was pants for me. Honestly the one I'd recommend and that works for me is the TeleVue TRF2008, but you must get the spacing right!

Here's one of my uncropped subs so you can see the FOV.