The differences between the SBIGs and the DSI are too numerous to list. Everything is different. From the imager, to the cooling, to the integrated guide camera, to the build quality, to the sensitivity, to the resolution, to the color reproduction. There's just no comparison at all.<br /><br />The difference between monochrome and single-shot color is pretty much what it sounds like. With monochrome, you put on a red filter, take a picture. Put on a green filter, take a picture. Put on a blue filter, take a picture. Then you combine them to get color. With a single shot color - that all happens in one step.<br /><br />Doesn't sound like a big deal until you realize that some of my exposures may be over 3hrs long. So instead of taking one 3hr picture, you're taking a 9hr picture. Ooops - not enough night-time!<br /><br />The SBIG is good - the Yankee Robotics is better, imho. If the budget is $10k.<br /><br />Sure, the telescope matters. The optics always matter. But with all things being equal, the imager in the CCD, how it's cooled, and how it shoots comes into play.<br /><br />Personally, I rarely use my home-built cooled CCD. (Similar to the DSI, it's a Sony Hyper HAD, TEC-Cooled, 512 line). I tend to shoot my Canon 20D DSLR instead. I just enjoy it more and feel more comfortable with it.<br /><br />It takes many years to get comfortable in astrophotography. You *must* be experienced with visual astronomy before you even start in astrophotography, imho. That being the case, a lot of the "what about the telescope" questions get pre-answered. <div class="Discussion_UserSignature"> <p>.</p><p><font size="3">bipartisan</font> (<span style="color:blue" class="pointer"><span class="pron"><font face="Lucida Sans Unicode" size="2">bī-pär'tĭ-zən, -sən</font></span></span>) [Adj.] Maintaining the ability to blame republications when your stimulus plan proves to be a devastating failure.</p><p><strong><font color="#ff0000"><font color="#ff0000">IMPE</font><font color="#c0c0c0">ACH</font> <font color="#0000ff"><font color="#c0c0c0">O</font>BAMA</font>!</font></strong></p> </div>