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View Full Version here: : 1.25" or 2"?


Scooter
17-08-2009, 12:03 PM
Hi Folks,

OK looking to get some new gear (like a new guide cam/planetary cam – just posted a thread seeking advice as to which on) and was wondering peoples thoughts on if I should go 1.25” or 2” for other accessories?

What I mean is currently I use my DSLR at prime focus in my 12” newt and this is done via a 2”. Now if I get a new cam (as per above – guide/planetary) it is going to be 1.25 (they all seem to be) so lets say I want a powermate (to give me some image scale on the planets) if I go for the 5x as it is only 1.25” I won’t be able to use the DSLR (or can I reducing the connection to 1.25” – that will cause vignetting won’t it?) connection however if I got the 4x powermate I will be able to use both. Same goes if I get an OFG – go 1.25” will limit restrict DSLR use so should I go 2”. Basically should I be looking to go 2” over 1.25” to allow flexibility later and with the DSLR?

That make sense at all?

Does anybody reduce the connection down to 1.25 for their DSLRs? I suppose it only is a question as I would still like to mess around with the DSLR and it has the 2” connection so I guess if I stepped it down to 1.25 (can you and at what cost?) then it becomes an easier choice - seems 1.25’ is a lot cheaper (the 5x powermate is a couple of hundred dollars cheaper than the 4x 2”) so potentially the 1.25 is the better buy.

Thanks in advance

gbeal
17-08-2009, 02:23 PM
Not 100% sure what you are asking here, but my advise is stay with 2" for your DSLR, and use a dedicated lunar/planetary/guide-cam in 1.25". This also means either a 2.5x or a 5x Powermate.
I can't think of why you would want to barlow the DSLR, but you will want to with the lunar and or planetary imaging.
Gary

Scooter
17-08-2009, 05:19 PM
I did ask if it made sense Gary :D

Guess it was about being able to use the DSLR if I wanted to. For example the other night I had the DSLR in a 2x barlow (have to to acheive focus with my newt) and was watching Jupiter magnified on the lappy via liveview etc. The D90 takes avi's as well so I guess I wanted to have a play with that at the increased image scale a 4x powermate would give me thus needing to stay 2"

That make any more sense?