New CCD

[Charles Dunlop]

http://www.optcorp.com/product.aspx?pid=319-320-1542-15881

What you guys think of this? I could scoop it up right now, with a rotator and be super ready to roll and guide off axis. Thoguhts?

[Russ Ruggles]

Sounds good - I'll be in touch with the info.

[Greg Marshall]

Russ, I'm developing this as a product and only have a prototype at this point. It will probably be production ready about a month from now. In the mean time, I will need to know the outside diameter of the front of your OTA (that is, including any trim) to custom cut the aperture. This (and a little black felt) provides a more-or-less light-tight fit so that you can use it without bothering your astro neighbors.

BTW, I'm still getting quotes from vendors, so the $45 price might not be the final list price, but I'll honor it for anyone on AstroGab.

[Russ Ruggles]

I'll take you up on the EL panel if you're serious.

[Greg Marshall]

OK, lots of rebuttal:
1. Dew does not form on the filters. They are very well thermally isolated from the cooled sensor. The sensor cover glass is where dew forms in most cameras, but this has never happened with my QSI583, despite operation in some really awful conditions.
2. Yes, download speed is annoying when doing flats, but what does that have to do with sky flats? During the day you have lots of time, so what is the problem?
3. I'd be happy to sell you a nice EL panel for $45 (up to 6" OD). In my setup it takes 15 seconds for an H-alpha flat. Less than 1 second for LRGB filters.
4. Yes, the focal ratio is somewhat limited. I shoot at f/5.6 with no problem. I also use camera lenses as fast as f/2.8 with no problem. But a hyperstar is not feasible with 1.25" filters.
5. I shoot at -15C in the summer and -25C in the winter. And the new 683 does even better cooling.

In summary, for some applications the 1.25" filters will not work and you can use either 2" or 36mm filters in the QSI. Otherwise, I see no merit in your argument and take offense at your assertion that QSI users are "not thinking clearly". I know that you use FLI and I'm sure they are fine cameras - if one can afford them. I note that you are quoted on their web site, so I have to wonder about your objectivity here. At the price point, I don't think you can beat the QSI 583 and, obviously, lots of other people agree. Likewise, at a much lower price the SBIG and other models are a good choice - just not quite as good as the QSI.

[Richard Crisp]

lots of comments in greg's post: let's analyze one by one
1) the use of the smaller diameter filters is only enabled by putting the sensor close to the filter which means close to the camera window. Be prepared to give up cooling to prevent dewing/icing.. that's the tradeoff
2) with the 20+ second downloads, the true irritation is taking flats not download speed during an imaging session. How can you take sky flats? You can't... is the answer.. so you have to
a) use something less than optimal like an EL panel that can give terrible results with some types of sensors
b) using an EL panel have to accept 90+ second flats for narrowband, which will require 90+ second darks to calibrate
c) have to pay back some of that 'savings' from the smaller filters by paying for an EL panel that may cost as much as $500

and bear in mind that the use of the 1.25" filters is only feasible up to a certain focal ratio: any faster and you need the larger filters.,

you are in this for the long haul, buy the 2" filters and be done with it... you can buy perfectly nice filters and not pay a king's ransom for it by using your head instead of following the crowd and playing monkey-see, monkey do...

and with the QSI what do you do in the summer when it is hot? you run at -5C or -10C, that;s what you do....

in my view it is the worst value proposition offered and anyone that buys one isn't thinking clearly

[Greg Marshall]

Charles, when I was looking at the various cameras built around the 8300 sensor it was pointed out to me that QSI's models were the only ones that allow you to use 1.25" filters and if you use narrowband filters the savings in these smaller filters more than pays the premium for the camera. I don't know if that's still true today. I haven't seen any reports on the SE, but I'd bet that the QSIs have lower read noise. Of course, that's partly because they read REALLY SLOW, but when you're doing 15 minute subs 20 seconds to download doesn't seem like much.

[Richard Crisp]

if I was a distributor and was dealing with SBIG, I'd only do COD orders: no way I'd give them cash in advance....

[Richard Crisp]

and they took on an additonal $1M SGD of bank debt too...,

[Charles Dunlop]

Lol Richard.

[Richard Crisp]

that's a great idea Charlie... I bet it is cheaper now than it was when AVI-Tech bought it for about $2.3M

they are hemmoraging money it appears and have run up additional debt... looks like they added at most $1M SGD of gross revenue but added over $3M in additional administrative expenses....

Looks like "washington progress" to me