Gordon Laing wrote:
Bob, are you getting cold feet over your possible 40D...?!
In every way bar one
it's my perfect camera but as you know my long term goal is FF.
In my thread Features of the Canon EOS 40D for scientific photography
I reported some of the new features of the 40D which I think will significantly improve the experience of using a DSLR at the telescope. Whether it is available as early as November or as late as February I have to believe the putative 5D MkII will include the same features as they are essentially firmware driven. In other words, without wanting to get involved in "wish-list speculation", the 5D MkII may well effectively be a 40D with a full frame sensor, albeit with a slower burst rate.
Thank you to you and your astrophotography friend for taking the trouble to compile the list of factors regarding the 5D's suitability for astro work. I guess all those factors are likely to be true for the MkII as well. The H alpha response is encouraging for grabbing the occasional nebula. Is he using the camera at the prime focus for this work?
The amplifier noise referred to would be a concern to me except that the MkII will have a new sensor so, hopefully, that issue will have been corrected. With ISO 3200 being usable I have to conclude that going FF doesn't mean any inherent increase in thermal noise over a cropped sensor.
To summarise, the 5D MkII is likely to give the same or better IQ for "normal" photography as the 5D does and do as good a job as any DSLR can when photographing the stars.
If my speculations on the 5D MkII are correct that makes it my perfect camera, period. The one sure thing is that I will have to make my decision to ask if I can "convert" my 40D pre-order into one for the 5D MkII before that camera is even announced! My timetable for replacing the 400D was initially determined by my intended good home for that camera but there are ways around that if the motivation is great enough and, even though it doesn't officially exist, the 5D MkII is beginning to provide that motivation.
Going straight to full-frame without the intermediate step of the 40D is a very big decision but one thing is for sure - if I go for it I can never
again make the excuse that I could take better pictures if I had a better camera.
Thanks again for your help.