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CCD Misc. Topics --Page 3

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CCD Topics on  CCD Page 4


 Subject: SBIG ST4 vs. Pictor 201XT   Top

From: Gene Horr <>

Dick Krick wrote:
> My funds are rather limited so I have been thinking about either
> the Pictor 201XT or the SBIG ST4.

Dick: I own both. The ST-4 is substantially better than the 201xt.

ST-4 Advantages:

(1) It is cooled -> lower "noise" -> can guide on dimmer stars
(2) The SBIG algorithms can track on poorer star images than the 201, making it more useful for off axis guiding
(3) The computer gives more information and has many more functions
(4) True mechanical relays. It can be used on just about any mount made
(5) High quality in design & manufacturing
(6) Great customer service

201XT Advantages:

(1) Much smaller/lighter
(2) Lower current requirements
(3) Solid state "relays" should give less problems in the long run than mechanical
(4) Cheaper

You can use the 201XT, especially since you are planning on using a guide scope, but the ST-4 is worth substantially more than the price difference.


Subject: Webpage with Tips for Autoguiding a Classic LX200 with ST-4

From: Matt Considine <> Date: Dec 2002

I finally got around to putting up a webpage with some things I've done to make autoguiding a Classic LX200 with a ST-4 a bit easier. It can be found at:


Subject: AO-7 Benefits --part 1 of 2

From: Mark de Regt <> Date: June 2002

> Then I read in this thread that the AO-7 will basically compensate for the
> problems in a standard LX200 mount, such that high-accuracy imaging would be
> pretty easy? This almost sounds too good to be it?

I belong to the SBIG yahoogroup, and I am consistently impressed with the improvement in quality people are getting with the AO-7, particularly when attached to an LX200. It certainly is the next thing on my wish list.

No question--if you have the bucks, go for the best you can buy. Matt used to image with a 10" LX200 and ST-7E; he is now getting excellent results from his FSQ-106/ST-10E/AP400 (his excellent image processing skills do not hurt, either). Note, however, that, with software, he has something like $15,000 sunk into that platform.

I certainly don't pretend that the LX200/ST-7E is anything like the "ultimate" platform; if I could afford it, I would buy the best equipment out there.. However, if they had "cost classes" in imaging, like they have weight classes in wrestling, I believe that the 10" LX200 would be the champion in the $3000 class, for OTA/mount/tripod. When you add the AO-7, it would be a real champion in the $4000 class, and, in the right hands, it would rival setups costing several times as much.


Subject: AO-7 Benefits --part 2 of 2

From: Ted Agos <>

Just a thought to add to this thread, I've run some tests with the AO-7 configuration and much to my suprise I found that for a fixed reducer spacing 118mm for the AO-7 there is a stricking difference between the spacing with various focusers, results indicate that the further you are from the backplane of the scope the worse the vigneting and optical edge distortion is.

I'm not sure, but I would think that your setup should come to focus as it now stands. you can easily check this out by moving the camera filter wheel 75mm (AO-7 added spacing) further back from the back of the focuser, and if you can come to focus then your OK. Will be posting a more detailed comments on my web site soon. <>


Subject: LX200 7" Mak and Large CCD Chips --part 1 of 3  Top

From: Mark de Regt <> Date: Nov 2003

-----Original Message-----
From: Gordon Mandell
Subject: [M]: LX200 Mak and Large CCD Chips
I am contemplating ordering one of the new SBIG Research line CCD cameras to use with my 7" Maksutov LX200GPS. With the SBIG 11000XM chip as large as a frame of 35mm film, should I expect problems with field flatness? If so, is there a solution that has worked for others perhaps using 35mm film, or should I look into another CCD camera?
-----End of Original Message-----

I assume that you intend to do deep sky work (else why a large chip?). The Mak is a wonderful scope, but its very slow focal ratio of f/15 and relatively small aperture will make it a challenging platform with which to image. I doubt very much whether its flat field is large enough for such a huge chip; I think your best bet, if you want such a large chip, would be to get an RC or an APO refractor with a flattener.


Subject: LX200 Mak and Large CCD Chips --part 2

From: Doc G

My sentiments exactly. A MAK which is slow and already has problems with field size is a poor scope for deep space. After all, with a $9000 camera, you should get an appropriate lens (scope). I suggest you consider a Petzval design refractor which is designed for large flat field. The new TeleVue NP127 would be nice. There are also several 5" Williams or Takahashi scopes that would be good. Even a fairly high line scope will be less money than the camera. You would have to go to an RC of at least 12 inch size to cover the camera chip you are considering. The RC at least has a reasonably flat field.

You choice of camera it way out of the class of the little MAK.


Subject: LX200 Mak and Large CCD Chips --part 3 of 3  Top

From: Peter Erdman <>

I think Mark's comments are quite correct. A similar discussion has taken place on the SBIG user group about the use of these very large arrays. I believe that only a few instruments are capable of utilizing them, and I doubt that the Meade Maksutov is one of them. Most instruments are designed for visual use with available eyepieces and 2" connections (at the largest). All of these will greatly limit illumination at the corners of a 35mm frame, and generally with less than acceptable optical quality. Film has hidden many optical sins over the years, but a small pixel CCD will certainly reveal them.

For a simple experiment, you could connect any 35mm film camera to your telescope and try imaging a bright star field. Look at the variation in spot size across the frame and realize that the CCD will be less forgiving--but at a lot more money. The high f/ratio Maksutov is primarily designed as a visual instrument giving reasonable magnifications with a relatively long focal length eyepiece. I have seen few images with it, but that does not mean it will not perform very nicely. The angular FOV will be small, but I would guess that something like the ST8 detector size should be very successful--with appropriate attention to tracking problems.


Subject: : LX200 & Starlight Xpress CCD Camera    Top

From: Chris Frye <>

>I use a flip-mirror directly attached to the MX5-C and a T-adopter to attach
>the combination to the back of the LX200. There is no way that the
>camera will clear the forks, my maximum altitude is about 65 degrees. I
>use no focusing aids other than the flip-mirror and the supplied software.
>Now this would drive me crazy. How do you stop the unit from slew through
>the zenith and knocking itself out of alignment?

I use a program on my laptop called "TheSky" by Software Bisque, this software allows you to set altitude limits and also displays them on the screen. The scope will NOT violate those limits, it will stop slewing and issue you a "Limits Exceeded" warning. If you are using the Meade keypad to slew, you can press the GoTo key to stop the slew at any time you sense danger, watch the scope carefully.

>Also, I was surprised at the MX5C raw images lack
>of color, and how sharp it appears after processing.

The MX5-C creates 2 files when you take a picture. The 1st file contains the Luminance data, the Black & White detail. The 2nd file contains the chrominance data, the color data. The "raw" image only shows the Luminance data and it is "corrupted" by the Chrominance data (seen as a crosshatch pattern superimposed in the raw image). As soon as you tell the software to generate the combined color image, the world opens up and a beautiful image appears.

> I understand the MX5C has half the sensitivity of the
>monochrome units. Has this caused any problems (overly long exposures, etc).

You are correct, the color version of the camera is half as sensitive as the B&W version. On guided long exposures, like nebula, it doesn't it can be a pain (1 sec on Jupiter Vs .5 sec at f/35) because atmospheric turbulence has twice as long to ruin your image. However, on the Moon .01 second works just fine on the color version with the Optec f/3.3 focal reducer, you would need a neutral density filter with the B&W version in order not to over-expose. By the way the Optec f/3.3 is great, but you can't use a flip-mirror with it.

>Do you have the port accelerator, and how long to download an image
>and how long between focus images? (mine seems awfully slow in this area).

I bought the port accelerator and I am very glad I did. I bought my laptop in Jan. 1996, an IBM "Thinkpad 760CD" using a Pentium running at 90MHz. I paid $7,800.00 it back then. (Please don't laugh, I feel bad enough).
It's probably worth about $700.00 now. Anyway, with the port accelerator, I get a picture download time of about 11 sec on my 90MHz, but that's not important, what is important is that I get a focus-mode update about every 3 secs. It is hard enough to focus the LX200 through the eyepiece, with it's image shift, dead zone on reverse focus etc. Try it when you can only see the image every 3 seconds!!! (Without the port accelerator it would be every 6 seconds). It's a MUST-Have!!!

>I have no way to guide at the moment, but will work on this. My next goals
>are an Optec 3.3, a guidescope, a Meade focuser and eventually an
>autoguider. I'm hoping I can get any/all of this to clear the fork, and use
>the scope remote in the cold weather. We'll see.

I have the Meade focuser, I don't recommend it, it focuses the main mirror, with all the inherent problems associated with this procedure, (focus slack zones, image shift etc.). If I could do it again I would recommend the Van Slike (sp) focuser. Go with Losmandy mounting plate and rings for your guide scope (very rigid). As far as an autoguider is concerned, there is simply no option. If you are using a small aperture guide scope (60 - 90mm) you will need a Peltier cooled CCD guide camera such as the SBIG ST-4. If you are using a large, and heavier, guide scope such as the C5 (125mm) then you might get away with the un-cooled Meade 201; however, I would HIGHLY recommend the SBIG ST-4 as the only option for guiding, it is still used by most professional observatories world-wide. Think about it, it cost $599 and the pros can afford just about anything they desire but they still choose this very humble, but reliable guide camera.


Subject: Experiences with the Starlight Xpress CCD cameras --part 1 of 2    Top

From: David Moody, Date: Dec 2002

-----Original Message-----
Wondering if anyone could comment on Starlight Xpress CCD cameras. Their new MX7C seems pretty intriguing to me, with single shot color and self-tracking. Are they too good to be true, and if so, what's the catch? If the technology works, why don't other cameras start offering single shot color? Herb Reiher ------end of quote-------

Generally speaking, the Starlight Xpress Cameras, especially the newer models such as the MX716 and HX916 are very good cameras that are up there with the competition, especially with comparable or better specs at a much lower price (I use the MX716 on a 10" LX50). Their biggest weaknesses, so far as I can tell, are:

  1. The software that comes with the cameras is lacking in many respects, and I think they realize this, too. Terry Platt has commented recently that they are working on those problems. Having said that, I use and have used MaximDL/CCD for quite a while now and would recommend that software for camera control regardless of what make or model of camera you are using, and I think most of the user base of Maxim would probably agree. I have used Maxim with two cameras now and I consider that one of the best overall investments I have made.
  2. Their product documentation is weak. I gain more from the yahoo groups and my own experience than from their documentation.

I have noticed from the Starlight Xpress Yahoo Group threads and inspection of images from the MX7C (one shot color), that color balancing can be a real problem with that camera, partly because of its built in CMY filters. Generally, you will get pretty decent color images, but if you ever want to calibrate the colors, it could be problematical. In the long run, you will get far better images, both in color and B&W using a good monochrome imager and filters. Because of the built in filters used in color image CCD's, there are just too many compromises that have to be made for astronomical imaging. This is why the competition has generally not gone into one shot color imagers. Apogee pre-announced a one shot color camera a couple of years ago or so, but they finally decided not to release it (apparently).

The STAR 2000 autoguiding system is a great system. I had some problems getting properly started with it because of problem 2) above, which was also a problem with MaximDL/CCD in this particular case. Once I got it all working, though, it has been wonderful. With proper polar alignment, I have tracked for hours on my LX50, just shooting away 5-10 minute exposures at a time, but letting the autoguider just run continuously. Using dark frames, I haven't had problems with the amplifier glow at all. It is absolutely wonderful to guide on just about any object in the CCD FOV and not have to worry about hopefully finding some obscure object near the edge or re aiming your camera to get a guide star included.

The newer Sony CCD chips that Starlight Xpress uses are superior in many respects (not all necessarily) to the Kodak counterparts used by SBIG and FLI. The Sony interline design is what makes the STAR2000 autoguiding system possible. That, SX's patent on STAR2000, and because a lot of the higher end cameras and imaging use external guiding chips or cameras (I do myself on occasion) is why you won't find it used by its competition.

Starlight Xpress, by the way, has just come out with a new camera that has an optional attached external autoguider camera, the SXV-H9. This is a megapixel camera (1392x1040 pixels) with some very nice specs (nice QE and very low dark current). It is also STAR2000 compatible from what I understand. It has built in 2.0 USB that is 1.1 compatible with a built in autoguider output and additional serial/parallel socket for focuser/telescope control. It will be interesting to see how this imager works out. This is clearly a big evolutionary step for them and I understand that the pricing for this rig will undersell the competition in terms of dollars per features, as does their other cameras.


Subject: Experiences with the Starlight Xpress CCD cameras --part 2 of 2    Top

From: Rob Bensko

I have an MX7C with Star 2000, which I use with both my 8" and 12" LX200's, and love it. The setup really does work as advertised and represents quite a bargain for the money. I'd be happy to send you some images I've taken with it, or if you'd like to see some *really* nice images, a friend of mine here in Florida, Alan Chen, has done some wonderful work with an MX7C and 12" LX200. His web site is

However, I do generally second David's excellent comments about the MX7C with regard to documentation, software and color balance. As for documentation, it could be better, but it's not bad and the Yahoo Group is a fantastic resource. Plus, Terry Platt of Starlight XPress is great about promptly answering emails about issues that come up. (Try emailing Bill Gates for advice on a Windows issue! :-) ) As for software, David suggests MaximDL, which by all accounts is a great program. Many Starlight XPress users, however, use Astroart, which offers great support for both the MX7C and LX200. At just $150, Astroart is also a great bargain and you can try out the demo for free first. As for color balance, yes it can be a little tricky sometimes but really not all that bad, especially in Astroart. You will get better color using a monochrome imager and a color filter wheel, but you might not want to mess with a color filter wheel.


Subject: LX and Starlight Connection --part 1 of 7    Top

From: Joe Shuster <> Date: Sep 2003

-----Original Message-----
From: Darren Carlisle
Just received a new Starlight MX716 camera and I notice that I have to plug the
Star 2000 lead into the RS232 port not the guider port. If this is the case does
this mean that I cannot use SkyMap and APC to control the scope now? What do
other Starlight Express users do?

Darren, you have two (more really) choices:

1) Use the flat cable to connect the CCD port on the LX-200 to the "Standard" port on the Star2000 interface box. This uses the Star2000 like a "standard" ST-4 guider. You can use your original serial cable to connect to the LX-200 RS232 port. (Of course you'd need two serial ports.)

2) Use the flat cable to connect the RS232 port on the LX-200 to the "LX-200" port on the Star2000 interface box. At this point the Star2000 is just another cable from the telescope to the computer and you can send multiple LX200 commands (not just guiding commands), but only one program will be able to control the serial port at a time.

There are more complicated scenario's, but those are the main two options. I think most folks use option 1 so they can have planetarium program control AND guiding simultaneously.


Subject: LX and Starlight Connection --part 2

From: Mike Smith <>

Here is another way. If you use the LX200 serial port for guiding, you only need one serial port. Guiding this way certainly works on the LX200 Classic but not on the LX200 GPS. Basically, the solution is to disconnect one program in software while the other is using the serial port. I use the Star2000 box connected to my laptop (which has 1 serial port) and the flat cable connected to the LX200 serial port. The Star2000 box basically passes the serial signals straight through in this configuration. I suspect it is also possible to connect the other output port on the Star2000 to the CCD input at the same time but this needs another cable. I use AstroArt 3 for the camera control and SkyMap Pro for the atlas as follows:

  1. Start AA3 and SkyMap together
  2. Use Telescope->Open connection to connect to the scope and then slew to the object to image.
  3. Click Telescope->Close connection when the scope has finished slewing.
  4. Go to AA3, set up to start guiding and click 'Connect' on the guiding window. AA3 at this point has control of the scope.
  5. After taking the guided image, unclick 'Connect' on the guiding window.
  6. Go back to SkyMap Pro and reconnect to the scope again to go to the next object.

This is the system I have used so far. One day I'll try an extra cable and plug it into the CCD input since guiding via this method apparently guides better. AA3 can guide using LX200 commands or special control codes which are picked up by the Star2000 box.

I suspect this procedure will work with other atlas software and camera software.


Subject: LX and Starlight Connection --part 3

From: Joe Shuster

Mike, I think what you suggest wouldn't work. The software that talks to the serial port on the computer (and to the S2K interface box) has to decide whether it's sending LX200 commands or ST-4 like guiding commands. (In AA, you need to pick one style.) I don't think it can intersperse the two. There's no way to connect a second serial cable to the S2k interface box.


Subject: LX and Starlight Connection --part 4

From: Mike Smith

Hello Joe, I think you misunderstand what I meant. One serial port is used on the laptop, but the Star2000 has one RS232 connector for the PC and two output sockets - the CCD output and the LX200 output. The LX200 connector is in fact just a feed through of the RS232 lead using a different cable and this would be connected to the LX200 RS232 socket. By connecting both Star2000 outputs to the LX200, the laptop RS232 output is permanently connected the LX200 RS232 input.

By selecting between ST-4 commands or LX200 commands for guiding, you can choose to guide using the CCD input or the LX200 commands without changing the connections. The only thing I don't know is how the LX200 will respond to ST-4 guiding commands - either get confused or ignore them. As far as I know, I have not seen anyone try this.

By alternately connecting the star atlas program and the camera software, one serial port allows two programs to cooperate and allow 2 types of guiding control.


Subject: LX and Starlight Connection --part 5

From: Joe Shuster

Hello Joe, I think you misunderstand what I meant.

JS>Always a strong possibility.

One serial port is used on the laptop, but the Star2000 has one RS232 connector for the PC and two output sockets - the CCD output and the LX200 output. The LX200 connector is in fact just a feed through of the RS232 lead using a different cable and this would be connected to the LX200 RS232 socket.

JS>Up to here, I'm with you.

By connecting both Star2000 outputs to the LX200, the laptop RS232 output is permanently connected the LX200 RS232 input.

JS>I doubt this was considered in the design, but it might not hurt anything.

By selecting between ST-4 commands or LX200 commands for guiding, you can choose to guide using the CCD input or the LX200 commands without changing the connections. The only thing I don't know is how the LX200 will respond to ST-4 guiding commands - either get confused or ignore them. As far as I know, I have not seen anyone try this.

JS>Me too.

By alternately connecting the star atlas program and the camera software, one serial port allows two programs to cooperate and allow 2 types of guiding control.

JS>I see. You would have to periodically disconnect and connect the software because only one would control the single PC serial port. Whether this works or not would depend on the amount of smarts in the Star2K box. If it can decipher guiding commands from LX-200 commands and exclusively channel them on the correct output patch, it could work.

JS>It's probably not a major sacrifice to give up telescope control from the planetarium program during guiding an imaging session nor vice versa. You might want to run that idea up the Starlight Xpress group flagpole and see if Terry Platt salutes it.


Subject: LX and Starlight Connection --part 6

From: John Mahony <>

The RS232 port on the scope actually has two separate serial connections. See the Topical Archives for details. So you could run one to the computer and the other to the quider. You might have to make a custom cable to do that, though.


Subject: LX and Starlight Connection --part 7 of 7     Top

From: Andy Heath <>

Question: Do I use the other port on the interface (not the LX200 connector)

Answer: Yes, use the ST4 port on the S2K interface.


Subject: LX200 Classic Dual Serial Ports -- part 1 of 2      Top

From: Greg Smith

>I saw a posting regarding the serial port of the LX200 wherein it stated
>that you could split the 6 pin into two serial channels and potentially have
>two separate software programs accessing the scope at the same time.

Yes, I have done this and it works fine, This is how I did it. You of course must have 2 serial ports on your computer. What you need to do is wire one cable just like the LX200 manual says to do. For the next one, wire the computer end up just like the first one, on the scope end, you need to use pins 6 on the scope for the serial in and pin 2 for serial out. This is what I have done and I use Skymap Pro 5 and Pictor. I am able to use auto focus and GoTo in Pictor and the slewing feature in Skymap. The one odd thing I have seen is that when I auto focus I need to close the connection to Skymap, if I don't, the location cursor jumps a little and the scope does not want to slew properly. This is no big deal, because to connect or disconnect through Skymap only takes a click of the mouse. Make sure you have all of your serial port settings right (address, IRQ, etc.).


Subject: LX200 Classic Dual Serial Ports-- part 2 of 2    Top

Marc Castel <> Date: Feb., 1999

Following up on a thread - I got "both" LX200 serial ports providing info to the computer under two different comports and various programs (I tried combos of Bob Denny's ACP, TheSky and DOS Basic Prgs). It worked very nicely.
Pinouts are as follows:

First Channel (as according to LX200 manual)
LX200                   Computer DB9
Pin 3 (pc transmit) Pin 3 Pin 4 (Ground) Pin 5
Pin 5 (pc receive) Pin 2
Second Channel
Pin 2 (misc serial out) Pin 2 Pin 4 (Ground) Pin 5
Pin 6 (misc serial in) Pin 3

I plugged a 6 wire phone wire into the LX200 then branched it with a 6 wire splitter (I purchased both at Radio Shack) and then used two 6 wire mini wires to plug in to the two separate RJ11 to DB9 connectors (which I got with my software prgs free- note software Bisque uses a non-inverting phone cable so I had to rearrange the pins in the RJ11 to DP9 connector I got from them). Make sure you get the wires right or you could blow the LX200 fuse.

I use the setup to track my LX200 Alt/Azm so that my computer can adjust the dome opening angle accordingly - this eliminates the need for any infrared or other mechanical tracking system -- I had no problems with software glitches.


Subject: FOV/Plate Scale Calculator-- freeware     Top

From: Cary Chleborad

Since I'm immersed in telescope mechanics / optical specifications etc, on a daily basis I wrote a quick and very dirty Field Of View / Plate Scale Calculator to help think about things. If any one is interested in playing with it you can grab it from


Note: should open a new browser window over this one.

You just plug in your optical and detector specs and it generates the field of view across the detector dimensions and shows the plate scale. There are a couple of pull down menus with selections that drop in the numbers for a given camera or detector. There are currently 12 cameras and 12 detectors to choose from. If a particular item is not available you can just manually plug the info into the edit boxes.

Keep in mind that this thing isn't perfect - there is no error handling so you can get it to generate some windows error messages (nothing serious) and it assumes that the detector pixels are square (read  I've fudged some of the detector specs). None the less, I find it quite handy - it lets you rapidly flip through telescope and detector combinations to see what your up against. One thing fun to note is the Texas Instruments TC-211 chip (SBIG companion autoguider). Plug it into your optical system and see what kind of pointing accuracy you need to put a star on the chip.


Subject: CCD -- Minimum Sampling Calculation     Top

From: Gene Horr <>

Dave Curtis wrote:

> The new ST-9E has 20x20 micron pixels which maybe more suited at f10
> than say 9 micron pixels (without binning).
> Would using a f6.3 focal reducer (75 inch focal length system) with
> 20mu pixels be acceptable with average seeing.
> A focal reducer at f3.3 would need
> a smaller pixel camera - is this correct?

This all comes from a pervasive myth that needs to be wiped out. A 20u pixel camera at 2m FL (~12" f/6.3) will be horrendously undersampled unless you have 7 or 8 arc-second seeing. A 9u pixel at this FL is perfect for fair to average seeing (2" - 3").

At f/10 the 9u pixel is perfect for slightly better than average (2") seeing. Unless the seeing drops below 4" the 9u is going to still give you a better image.

Remember, the _minimal_ sampling should be pixel FOV = seeing/2. The _optimal_ sampling is closer to pixel FOV = seeing/3.

This is all assuming that you are trying to get good images, which your post implies.

This "large pixels" cr*p basically came from an article in "CCD Astronomy" several years ago. The author really pushed undersampling (basically FOV = seeing) as being great _for_the_ beginner_ as it covers up errors. Which it does. But it also means that (1) you'll be severely hindered in improving your skills as you'll never see your errors, and (2) when you finally do improve your skills to where you want to take good images you have to go out and buy a new camera.

Now, not only is this very bad advice, people read the article up to the point where it says "for the beginner" and ignore that point.

The ST-9 is a camera for the longer FLs (in excess of 3m FL). The C-14s, 16" Meades, 18" and 20" RCs and the like. Buying it for 3m FL is marginal. Buying it for 2m is a big mistake. Assuming one is trying to get good images.


Subject: Second Laptop Serial Port via USB   Top

From: Don Tabbutt <> Date: March, 2000

For information only:
I needed a second serial port for my new Dell laptop so I could run my 208XT and LX200 at the same time. I decided to exploit the laptop's USB port, and ordered the Xircom (formerly Entrega) 9-pin Serial to USB adapter from MicroWarehouse ($65 US, including shipping). This device looks like a small dongle that plugs into the laptop's USB port and has a 9-pin serial connector for your serial device to plug into.

There were some interesting bugaboos I thought I may have to overcome:
  The laptop's "real" serial port was Comm. 1.
  The laptop's IR port was Comm. 2.
  The PC Card (PCMCIA) modem/LAN was Comm. 3.
  The "virtual" IR port (used to communicate with my Palm Vx) was Comm. 4.

As you may know, PictorView only lists Comm. 1-4 as choices for the camera and LX200. I was afraid the adapter would end up as Comm. 5, leaving it unavailable to PictorView. However, the installation program (or maybe Windows) moved the modem to Comm. 5 and put the adapter's port on Comm. 3.

It works as advertised, both with the camera and the LX200, and may be of interest to those looking for a similar solution.


Subject: Macintosh and Pictor 216XT   Top

From: Frank Santore

In a message, <> writes:

I'm attempting to drive a Pictor 216XT from a Macintosh 1400C running Virtual PC. I know the "comm port" on the Mac is live, as I can use it PC emulation mode with Kermit to communicate with Kermit running on another Mac.

In the case of the Pictor setup, I have a number of serial cables using various pin footprints, and sex converters between the Pictor and the Mac. As far as I can tell, everything should be correct, but something is obviously not right.

At the moment, I'm attempting to run the flat black RJ12 cable to the RJ12-DB9 Adapter, both of which came with the Pictor 216. From there, a Male-Male DB9 adapter. From there, to a Female DB9 to Mac serial cable. Yes, I know it's a kludge, and making my own cable is the next obvious step...

Does anyone in the group have experience with this for the configuration I've described... pin out diagrams, etc.

Any help would be appreciated, particularly if you've used a Pictor in conjunction with a serial port on a Mac running Virtual PC!


Brian - I've controlled my Pictor 216 via Powerbooks since it was introduced At the time I was using a Duo 230, a 5300cs, then had a 1400cs for a couple of years, and am currently using a Wallstreet. The serial cable to the Pictor should be identical to a cable used to control the LX200 from a planetarium program such as Starry Night, The Sky, or Voyager SkyPilot.

My suggestion is get this working first, then move to the Pictor control. BTW, I used a PC Card on my 1400 for the second serial port to control both the LX200 and Pictor at the same time. The cable can be had from Charles Turner who advertises on Astromart, from Carina Software, or you can build it using the info on the MAPUG-Astronomy Topical Archives. Another source is a very nice former Aussie who markets some good products at


Subject: Pictor 416XT SCSI Error NO Aspi   Top

From: Ralph Pass <> Date: Feb., 2000

Ed Genord wrote:
Here is my problem: I cannot get the 416xt to communicate with the laptop. When I launch the pictor software I get the folowing error message: "SCSI Device Error Adapter Inquiry was unsucessful, No ASPI, so no message tried" and here is my set-up:

Pictor 7.0 software
416xt CCD
Eiger Labs EPX-SS1000 SCSI PC card
Fujitsu 656xt 150mhz pentium laptop
Windows 98

In Pictor.ini I tried both 1 and 0 in the adapter setting and no change in outcome. One thing that should be noted is that in the set-up preferance page in the pictor software Ihave no selection for adapter number is this correct?


1. On the preferences screen, is there a drop down list for the adapter number with 0 and 1 in it? If not, then your scsi adapter(s) are not being seen.

2. Verify that there is the line:
SCSI_LUN = 0 in the SCSI section of the ini files.

3. Is your scsi card a PC Card or a PCMCIA card (that is 16 bits or 32 bits)? My PC Card 'cards' have a gold colored strip on top of the connector end and has eight bumps on the strip. The PCMCIA cards are smooth on both sides.

On second thought, the 'No ASPI' message means that the ASPI dll could not be found, hence was not loaded, hence no communication with the Pictor. See if you can find wnaspi32.dll or winaspi.dll and move it to a directory that is in the windows search path.


Subject: CCD University URL   Top

From: Jan Sandberg, Date: April, 2000

I found this website is very informative regarding CCDs and their selection:
   <> Note: should open a new browser window over this one.


Subject: CCD Unguided Time on a LX200? --part 1 of 3  Top

From: David

I have A ST-237 CCD on a LX200 10" f/10. The scope is setup outside in a roll-off roof shed, I have done drift alignment and PEC training. I think I need to do some more fine adjustment to both. I can get fair pics up to 20 secs. My question is how long of a pic exposure can I get using it unguided before I need to use a guidescope. I'm guessing that a 6.3 or even a 3.3 f/r would expand the amount of time that I could get. I also understand that by adding the guide scope adds weight and other problems. (so if I can stack 30 sec or better pic.s that would cut setup time and the amount of time it takes to learn to use them together.)


Subject: CCD Unguided Time on a LX200? --part 2

From: Gregg Ruppel <ruppelgla_tSLU.EDU>

David, I have the same setup you describe using a Cookbook 245 camera. At f10 about 20-30 seconds is as long as I can integrate unguided. When I add an f6.3 focal reducer the times can be extended to 1-2 minutes. At f3.3 the times can be extended to approximately 4 minutes. It sounds like you have your alignment and PEC optimized about as well as can be expected. Tracking and stacking is the way to go.


Subject: CCD Unguided Time on a LX200? --part 3 of 3  Top

From: Bob Denny <>

After PEC training and a 10-minute drift alignment, I can routinely get 5 minute unguided exposures on my 8" LX200 with the f/6.3 reducer.


Subject: CCD Image Processing Tutorial URL Top

From: Steve Stefanik, Date: Sept., 2000

I am so impressed with Digital Development (DDP) with StellaImage2 that I could not stand to see my shot of M13 (greyscale) on my web page without it so I reprocessed it. I went a step further and put 4 shots of M13 side-by-side for comparison.
  1. the raw image
  2. the image processed with CCDOPS only
  3. the image processed with DDP using StellaImage2 only
  4. the image processed with LR using CCDSharp

If you are interested you can find them below my tutorial on image processing near the bottom of the page at:
   Note: should open a new browser window over this one.


Subject: CCD Photometry Tutorial PDF URL

From: Tim Hager, Date: Sept., 2004

I think this is what you're looking for is here:

<>  Note: should open a new browser window over this one.

The file name is: "wrccd4a.pdff"


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