Yep it sure is. I bought it around a year ago for terrestrial photography, then after a couple of viewing sessions with David (Prickly) and his Vixen/EQ6 set up we got the idea of piggybacking the 350D/70-200 f2.8 on the scope. Had our first try of it a few nights ago and it seemed like a lot of fun.
Can't wait to get my 40D and 70-200mm f/2.8 L IS .
How have you mounted the lens + camera on the EQ6 ?
I am thinking of an arrangement that used both the lens mount and the camera mount, to keep lens and camera as rigid as possible.
Also wondering if a teleconverter (1.4x L style) is worth getting ?
excellent image with 2 of my favorite objects! Nice focus too, looks near on perfect... now mod that 350D
Ian: I too can not wait to get a 70-200 f/2.8L for my canon (which Im getting friday, modding hopefully by next week..)
I will say this on Teleconverters. Whilst they do increase your focal length by the amount specified... they will also lower your max aperture. I cant remember the exact amount, but I think its something like with a 2x teleconverter a 2.8 becomes 5.3~5.6 not exactly sure..
Be sure to remember that on a 1.6 crop camera (300/350/400/450/10/20/30/40 D series cameras) the 70-200 lens is effectively a 112-320 or there abouts... the extra focal length provided by a 1.4 or 2x TC is nice.. but relatively unnecessary
If I remember how they work , a 1.4x will add one extra stop , or double the exposure required.
I don't mind that as sometimes I may want to have a tighter view of something (like a comet , a particularly nice nebula or cluster , a person , a bit of scenary somewhere ). And at only about $300 ish extra , that bit extra versatility seems handy, beats lugging about another zoom.
Thanks for all the , David and I just took a peek into the void that is Imaging, how deep does it go?
Ok guys, here are a couple more taken on the same night, with the same set up.
Antares Region, only 4 mins of data before the batteries gave up Plus we were off with the alignment a little so most of the interesting stuff is out of the frame. There is always next time.
You asked how we mounted the lens - we used a fairly heavy duty manfrotto ball and socket screwed into a bit of wood. The wood was screwed this into the top of the tube rings. Its a bit rough and ready but fairly low tech and it works. It seemed quite well suited to Michael's lens which sat pretty securely.
I have had a C90 mounted on the platform with the ball and socket as an autoguider when imaging through the main refractor and that worked ok too.
David and I just took a peek into the void that is Imaging, how deep does it go?
Answer: He He He He Heeee... (insert menacing grin here..) From what I've gathered after my few weeks of falling and not hitting the bottom.. It goes DEEEEP!!!
Can't wait to get my 40D and 70-200mm f/2.8 L IS .
How have you mounted the lens + camera on the EQ6 ?
I am thinking of an arrangement that used both the lens mount and the camera mount, to keep lens and camera as rigid as possible.
Also wondering if a teleconverter (1.4x L style) is worth getting ?
Hi Ian,
You may not need to mount both lens and camera.
As I recall the f2.8 comes with a sturdy tripod ring adapter.
I attach my f4 lens/tripod ring to the mount with this handy dovetail bar... https://www.bintelshop.com.au/Images/Stock/7734X.jpg
(about $30 from bintel)
Combination is rock solid.
I use the EF 1.4x extender with my 70-200mm f4L and it's great.
This Eta pic was taken at 280mm FL, with lens + extender... http://s231.photobucket.com/albums/e...A-POST-MOD.jpg
Stars are still points out to the edges of the frame, gotta love that!!!!
Drops f ratio one stop, but I wouldn't say that you needed to double exposure times though.
1.4x gets a good rep, but the 2x isn't as highly regarded I've read.
Cheers
Doug
The dovetail bar is a great option for mounting the camera Doug
I'd like to eventually get the 1.4x teleconverter to go with the 70-200, as Doug mentioned it only drops it by one f-stop, I believe the 2x version reduces the effective aperture by 2 stops.
David recently revealed to me that he has a Tamron F2.8 with a fixed focal length of 300mm, might put the Canon back into the camera bag for the next imaging session.
As Michael says - thanks for the idea with the dovetail plate. What a handy piece of kit! I can see that being helpful for the 300 f2.8.
Oh dear - more to add to the wish list!
Cheers
David
No Worries,
Luckily it's not too expensive!
I bought one of the generic "for Canon" tripod rings off ebay and found that the screw on the dovetail bar was too long and that the tripod ring was loose. A couple of small washers on the underside of the dovetail bar rectified this and the bar still fit snugly in the dovetail...does that make sense to you!!
Plus we were off with the alignment a little so most of the interesting stuff is out of the frame. There is always next time.
