Hi Guys, I stand confused right now as to what to do next. I just need some advice on my situation as im tempted to get all of them but due to lack of funds and other piorities, i have to stick to only one option
Im kinda leaning towards the DSI 2 if I sell my DSI 1 as im use to the software for it. With a DSLR, I have no experience whatsoever with the settings, software etc so might find it hard to use but the photo quality are fantastic. With the ED80, I feel it will be nice to take widefield shots with the DSI combined.
The ed80 will give you a focal length of 600mm compared to the 800mm of your current scope, so not a big difference in field but much longer exposure time.
The ed80 will give you a focal length of 600mm compared to the 800mm of your current scope, so not a big difference in field but much longer exposure time.
Will the 350D come to focus in your newt?
noobie question: so no big difference in field of view with the DSI on the ED80? not quite sure if the 350D will come to focus in my newt
Exposure time will be nearly double with the ED80 (goes like the f-number and the ED80 is an f7.5).
I believe that the DSLR in the f/4 Newt will give a wider FOV than the DSLR would in the ED80. But coma will probably be an issue with the Newt + DSLR combo. You've got to do a lot more homework to be able to make an informed decision.
All that said I would get the DSLR, just because that's at the top of my own wishlist atm.
IMO get the 350D and keep the DSI as Paul suggested Eric, if you don't have the funds for the 350D then wait, the sky will still be there in a few months; even a year. The price of the 350D will probably drop as well.
I believe that the DSLR in the f/4 Newt will give a wider FOV than the DSLR would in the ED80. But coma will probably be an issue with the Newt + DSLR combo.
No Steve, the determining factors for fov are focal length and chip size only.
This is analogous to focal length and eyepiece aperture stop.
Exposure time vs f-ratio is a constant, so for any given focal length increased aperture gives faster f-ratio enabling shorter exposures.
Im thinking that the DSLR may still give superior images to the DSI in the newt. If you can crop the comatic edges and still have a wider fov and higher resolution than with the DSI you are in front.
Somebody more familiar with the chip sizes and pixel counts may be able to shed light on this.
If this is a goer, at least Ezy can get an incremental benefit, rather than buying an ed80 and going backwards with the DSI.
No Steve, the determining factors for fov are focal length and chip size only. This is analogous to focal length and eyepiece aperture stop.
Yes, I was meant to write DSLR+Newt vs DSI+ED80 - the options Eric is considering. Probably larger FOV from the DSLR+Newt combo, because the DSLR would have a larger chip.
F= Focal length
w= length or width of chip
both units the same, usually mm
There for Fov for newt with 350D = 22.2/800 x57.3 = 1.59 deg wide
by
14.8/800 x 57.3= 1.06 deg
There you go. DSLR has a huge field compared to the DSI! Over 4 times as large. So even if you need to severely crop the image to keep coma under control you'll still have a much bigger FOV (not to mention much better resolution). So go get that 350D! That's an order!!
Will your optex scope carry the weight of the 350D ?
If its a typical chinese r&p focuser it might be advisable to upgrade to a crayford. I've heard that optex are made by gso, so the gso crayford might be a drop in replacement.
![[1ponders]'s Avatar](../vbiis/customavatars/avatar45_9.gif){kind=avatar}
Probably larger FOV from the DSLR+Newt combo, because the DSLR would have a larger chip.
