Ah ha, I just bought a new toy which will give me a 105mm telescope at F2.8 with a completely flat field for my QSI, when it gets here in two weeks I'm going to do some wide field Ha imaging. :-)
Any guesses?
5 elements in 4 groups :-)
widefield eyepiece?
I bet it's a prime focus camera lens and if it is free of aberrations wide open at F2.8 then it must have cost a small fortune.
Mark
Ok, its made in Germany and Japan!
Tak+FR?
Nope, ok I can't keep things quiet, I'm buying a Zork medium format to t-2 adaptor and a couple of pentax 6x7 lenses for 105 & 300mm imaging, F2.8 and F4. Should have an advantage over SLR lenses because the 6x7 is optimal in the 2/3rd image circle.
All in 2xlenses and adaptor £450, going to get the cheaper lens 1st, I thought long and hard about this, if it works well I'll get an APO lens still cheaper than a tak. Will keep you posted.
Chris, you are so funny....can't keep a secret!!!!!!
Been looking at those 6x7's for a while so I'd be very interested to see how you get on with the 105mm especially if you can use it wide open. Some of the shorter f/l lenses are quite inexpensive but as I've recently found out with a supposedly sharp 50mm f1.2 Pentax lens, it's not so impressive if you have to stop it down to f5.6 to get edge sharpness.
btw. I thought the Zork adaptors were quite expensive, did you manage to find a cheap source?