Eyepieces for 12 inch Lightbridge...

Greetings all,
I wanted to get some opinions on this:

Basically, I've got a chance to buy a 12 inch light bridge in about a month or so. I should be good and sell one eyepiece, since I've got only $500 in my astro account. Although I'll point my scope at most anything in the sky, my primary love is deep sky objects. I'll still use my 8 inch as a grab and go setup when at my apartment. "The Night Sky Observers Guide" seems to recommend 100-125x for most deep sky objects. I've been playing around with eyepieces. But with my 8 inch, I always pull out the 24pan first and look a while, then drop to the 13 T6, and then will pull out the 7T1 when called for. Honestly, I'm perfectly content to use those 3 only 90% of the time on my 8 inch. Occasionally I will pull out the 40mm wide field for amazing 2 degree TFoV views. I've also got a 9 T1, but haven't had a reason to pull it out of the case since I bought the 7mm about 3 months ago. So, considering both scopes, magnification, TFoV, exit pupal, etc... which would you sell to finance the purchase? Other suggestions? Basically I'm wondering how different 12 inch f/5 will be from 8 inch f/6. I've only looked though sct's in the 11 to 12 inch range.



Thanks for taking time to read all of this...

Brian

Brian:

With the longer focal length of the 12 inch you will be operating at somewhat higher magnifications so that is something to be considered...

What should you do... Since it is your least favorite eyepiece, I would sell the 9mm T-1. But since a 9mm is an important eyepiece, a -2mm exit pupil in an F/5, I would purchase a used Synta 9mm Widefield. I have measured the effective AFoV at about 70.5 degrees and they are surprising sharp right up to the edge. I used mine for maybe 5 years and for most of the years it sat next to a 7mm Nagler... It was only when a deal on a 9mm T-6 showed up locally that I finally replaced it.

These normally go for around $30-$35 here on Astromart and go by a number of names, Orion Expanse, Antares 8.6mm W-70 as well as various others...

Best inexpensive widefield I have ever used, very similar in design to the Burgess/TMB Planetary eyepieces but with a significantly wider field of view.

Jon

Brian--
I know you like it, but how about selling the 7mm T1 and getting a 2x TV barlow? (You'd net about $75.) Then you'd have a fair spread of powers (115, 170, 230, 340 from the 13mm and 9mm alone). And I would say the barlowed 13 T6 is actually a superior eyepiece to the 7 T1. Only drawbacks would be the 9T1 is a bit awkward in the barlow, and you limit yourself in powers in the 8".
You could also get by without the 40mm (it will be less fun at f/5, but still useful for finding things), as the 24 pan would be giving you over a degree in the new scope.
If your significant other (I'm assuming that's the main spending bottleneck) would let you have your cake and eat it for a couple of months, my suggestion would be to try out the eyepieces in the new scope before deciding which to cut loose.
By the way, the 12" will be a real eye-opener after the 8".
--geo

Don't sell anything, don't buy anything, just use what you have. By the autumn it all will be clear to you.

Dmitri

Thank you guys so much for your input. At this piont, I'm leaning towards parting with the 9... In a perfect world, I'd get the scope and try everything out. Perhaps I can somehow manage to put a Seibert 2.5x amplifier onto the bridal gift registery...

I have this history of "trying" equipment then never getting around to selling the stuff that I had planned on to "finance" the new equipment. :S So as I said, the plan is to part with the 9 for the time being, then get the amplifier at somepoint in the future...