From: Mark Gaffney <markgaffney@me.com>

Date: February 5, 2010 4:46:49 PM MST

To: Astro_IIDC@yahoogroups.com

Subject: Re: [Astro_IIDC] Re: new filter wheel...!

Hi Milton,

My TIS camera is a .AS one & as you`ve said I`ve been able to go to ..At up to 1FPM to... 30 FPM upon plugging it in. I wasn`t aware of this before!

Taking into account what you were saying about the Scorpion`s sensitivity previously, I`ve been looking at M 83 The Southern Pinwheel Galaxy as a case in point & at 0.63x reduction (I`m unsure if the galaxy`d fit in the FOV-different readings on different apps.) & Sky Tools (which is the only gauge-exposure calculator I have), is proposing at 1628 x 1236 pixels & a SNR of 7 (described as detectable).. 2 x 60 minute exposures for an IR cut Luminance filter & 8 exposures of 60 minutes for Red or 10 of 60 minutes for Green... but for Blue I think it said 87 exposures of 60 minutes! If I turn the SNR down to 3 (marginally detectable) for Blue there`s only 16 (!) 60 minute exposures. These readings are similar with a ROI of 814 x 618. If this is right, photographing this object would be the work of many, many nights!?

The Flea 2`s now on it`s way back to Canada to be fixed on warranty. I have one of the 6 pin to 4 pin FW adapters in the mail (it may have even arrived at the post office already-supposed to be delivered overnight!). I don`t need it though to run the Scorpion from the iBook & will test (probably on M 42) when this cloudy weather goes away..

Mark.

On 06/02/2010, at 5:19 AM, milton_aupperle wrote:

Mark;

Nice wheel and rig.

If it's an .AS TIS camera, you can do exposures up to 60 minutes without needing the trigger pin setup that PGR use. The "normal" TIS camera other cameras were either 30 or 60 second exposures (I forget now) and don't support bulb trigger, so that's the max exposure they can do.

And the only difference between TIS "normal" and .AS cameras is the Firmware load, they are exactly the same camera physically.

I have been asking PGR for 3 years now to implement something like that in their own firmware, but my requests and suggestions fall on deaf ears. TIS got it right the first time.

If PGR had done that, I could have put together a schematic for a Hirose connector so that you could hook it up to either a RS232 serial port or possibly even an ST-4 port. The camera could directly talk to your mount and you would not need a USB to Serial or a GPUSB for guiding.

TTYL..

Milton Aupperle

--- In Astro_IIDC@yahoogroups.com, Mark Gaffney <markgaffney@...> wrote:
>
> By the way Alberto,
> I was wondering how you got by the "time exposure" problem with your
> TIS cameras. Don`t you have to open the shutter for an extended time
> when doing your pictures of DSO`s? PGR cameras have this option but I
> thought TIS ones didn`t..?
>
> Mark.