orenabah
member
Reged: 05/21/08
Posts: 88
Loc: Connecticut
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So the other day I decided to take a shot at working my DSI pro. I took the advice that many people give - photograph a terrestrial object first to help with focus and whatnot.
So, I get a few focused pictures (link). Then, last night, I took it out for the real deal, and decided to try something bright first - Jupiter.
Here's where the problem came in-- moving the focusing tube of my scope inward is the way to focus the DSI, but, the tube doesn't move in enough to get perfect focus/it's as far in as it can go. (This is what Jupiter looked like)
So what do I do now, to get this to focus?
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Celestron NexStar 130 SLT
Celestron NexImage
Zhumell 20x80 binos
Meade DSI pro
Panasonic DMC-TZ3
Edited by orenabah (07/27/08 03:39 PM)
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nofxrx
Pooh-Bah
Reged: 07/12/05
Posts: 1465
Loc: palm bay,florida
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What kind of scope are you using?
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Brent Oliver
3 Wonderful dogs: Sadie, Kara and Ozzie
Celestron C10-N///C9.25///Orion 80ED///WO ZS66SD White
Celestron CI-700 & ASGT Eq. Mounts
Nikon D40Xa///SBIG ST-402ME/Class 1/CFW///DSI-PRO...
My Gallery
Ohh yeah,and a VERY undersanding wife!! 
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orenabah
member
Reged: 05/21/08
Posts: 88
Loc: Connecticut
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A Celestron NexStar 130 SLT, f/5 and a 650mm focal length.
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Celestron NexStar 130 SLT
Celestron NexImage
Zhumell 20x80 binos
Meade DSI pro
Panasonic DMC-TZ3
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fishmagnet
sage
Reged: 12/11/07
Posts: 268
Loc: Satellite Beach Fla
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I'm no expert but from your image it looks to me like you need back focus. This means your camera needs to be farther from the lens or mirror of your scope. Place your camera in a diagnonal the next time you try to focus on Jupiter and see if it will focus. If it does come to focus this means you need the extension tube.
*****John
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Vixen ED 103S refractor
Celestron C8 SCT
Takahashi EM 11 Temma II Jr
Astro-Tech AT66ED
SBIG ST-10E CFW-8
Meade DSI Pro II monochrome CCD
Atik filter wheel
JMI Robofocus
Philips PCVC 740K ToUcam
Registax 4.0
Photoshop CS3
MaxIm DL4
The Sky 6
Astro-Lab Roxy
Member Brevard Astronomical Society
"Starin' at the stars in a distant galaxy; wonderin' if there's someone out there starin' back at me!"
Fountains of Wayne
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lernerda
sage
Reged: 01/21/07
Posts: 353
Loc: New Jersey 40.0 N 74.9 W
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Also, while the DSI pro can do planetary,it is most defiantly a DSO camera (as we have been discussing in another thread)
I suggest a relatively easy DSO target, such as M13 or M57. Also DO NOT save in jpg (or even bmp) Try tiff, or even better one of the fits formats if you know how to use that(with jpg & bmp, WYSIWYG.. you cannot adjust the levels beyond the image you see in envisage)
If, you save in jpg, or bmp, it is not a tragedy, but you are limited in how much processing you can do with the image with programs such as PS or GIMP. Tiff would be good for now.
Also, your focus looked a little soft. Try some focsing techniques such as using a hartman mask.
Don't worry, you'll get there... here is my first using the DSI pro First m42
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David
www.seeingafterdark.com
Meade LX90GPS 8" SCT, Meade ETX 90, 10" f6 Dobsonian
Meade DSI-C, Meade DSI Pro II with IRGB filter set, Philips SPC900NC Webcam
Televue 3X Barlow, Meade 6.3 FR, 3.3FR
Meade 4000 set, ranging from 6.4 to 40mm, Planetary, LP, UHC, and Ha Filters
25x100 Busnell, 20X80 Konus Binocs, and homemade P-mount
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orenabah
member
Reged: 05/21/08
Posts: 88
Loc: Connecticut
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Well, yes, I'm aware of the DSI being a better DSO than planetary camera. The night before last, I had tried it on a bunch of stars in Cygnus (just because my alignment REFUSED to cooperate and take me to any decent DSOs) and I had the same problem.
When I first took the shots of the stars / Jupiter, they were in FITS but you can't really post that online can you? :P
Edited by orenabah (07/27/08 04:36 PM)
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Jerry3672
Vendor - Quantum Astronomy Products
Reged: 01/20/08
Posts: 295
Loc: Lexington NC
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I had the same problem with my DSI pro. My meade SN8 had an extension on the focuser. After I removed the focuser extension, I was fine.
I have replaced the Focuser with a William-Optics Low profile Crayford. You may have to get a focuser if you don't have any extensions on the stock rack and pinion focuser. I downloaded the manual for your scope, and didn't see an extension.
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Meade LXD75-SN-8
C11
DSI Pro
Sony H7
Canon XSi 450D unmod
www.spike-a.com
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orenabah
member
Reged: 05/21/08
Posts: 88
Loc: Connecticut
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No, the closest thing I have to an extension is the 2" to 1.25" reducer on the focusing tube...
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Celestron NexStar 130 SLT
Celestron NexImage
Zhumell 20x80 binos
Meade DSI pro
Panasonic DMC-TZ3
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RandallK
professor emeritus
Reged: 11/10/06
Posts: 730
Loc: Nanaimo, B. C. Canada
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My Orion Starshoot would not focus with my 5" Newtonian with the camera nosepiece affixed. Removing the nosepice and threading the camera on the end of the focusing tube solved my probelm of the needed inward focus. Can you remove the nosepiece from your Meade and thread it to your focuser tube directly?
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Scopes: Meade SC-8AT w UHTC
SkyWatcher 5" F/5 Reflector
SkyWatcher 127mm MAK
Mount: HEQ5 Pro
Cameras: Orion Starshoot DS Colour Imager V.1
Imaging Source Webcam DMK21AU04.AS
Palm TX PDA w Astromist and Bluetooth wireles control.
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jgraham
Postmaster
Reged: 12/02/04
Posts: 5386
Loc: Dayton, Ohio
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If the focus is close you could try moving the primary mirror forward just a tad; sometimes screwing the adjustment screws in a bit is enough. Plan B would be to replace the adjustment screws with longer ones. Plan C; if you're only going to use the Pro as a monochrome imager you can replace the filter slide with a low profile face plate from ScopeStuff. This will move the CCD array about 15mm closer to the focus. (I've removed the slides from both of my Pro's.)
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-John
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Homebuilt scopes from 4.25-16.5"
Meade LXD75-N6/SN6/SC8, DSX-90, ETX-60BB, ETX-125PE, DS-2130
Orion StarBlast, BinoViewers, Coronado PST
Rebel XT/XTi, DSI Pro (I & II), DSI, LPI, Electronic Eyepiece, Phillips SPC900NC
Tasco 60mm Refractors
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Jerry3672
Vendor - Quantum Astronomy Products
Reged: 01/20/08
Posts: 295
Loc: Lexington NC
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If you choose the low profile plate, you can still do RGB photos. You then remove the camera between colors and add the Red, Green, and Blue filters to the end of the IR filter.
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Meade LXD75-SN-8
C11
DSI Pro
Sony H7
Canon XSi 450D unmod
www.spike-a.com
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orenabah
member
Reged: 05/21/08
Posts: 88
Loc: Connecticut
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@RandallK: I could try but I don't think that'd help..the camera's nosepiece just fits into the tube. Maybe I'm wrong here but screwing it directly onto the focusing tube doesn't seem like it'd make much difference.
@jgraham: Well, I don't really know how close the focus would have to be for that - in my experience with this scope, where the image was would probably require around a full turn of the knob to put into focus. Would mirror adjustment fix this? I'm also assuming that it wouldn't mess up focus with regular EPs..just maybe change their in-focus area a bit.
I would like to eventually take color photographs, and I suppose I could just screw the filters on one by one..and just bite the bullet and get something like an LPI for the planets.
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Celestron NexStar 130 SLT
Celestron NexImage
Zhumell 20x80 binos
Meade DSI pro
Panasonic DMC-TZ3
Edited by orenabah (07/27/08 10:25 PM)
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jgraham
Postmaster
Reged: 12/02/04
Posts: 5386
Loc: Dayton, Ohio
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One way you can determine exactly how far off you are is to measure the location of the focal plane. Place a piece of thin white paper or wax paper over your telescope's draw tube and focus an image of a distant object on the paper. This marks the location of of the focal plane. The distance the draw tube is out from being fully retractd is the amount of in-focus you have available. With the los proflie face plate you'll need 3-4mm, with the filter slide I believe you'll need about 15-17mm.
Another way to bring the focus out is to use a very mild Barlow; something like a 1.25 or 1.5x. These are often used with binoviewers on Newtonians that don;t have enough in-focus. If you're going to image planets a much stronger Barlow may prove useful.
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-John
================================================
Homebuilt scopes from 4.25-16.5"
Meade LXD75-N6/SN6/SC8, DSX-90, ETX-60BB, ETX-125PE, DS-2130
Orion StarBlast, BinoViewers, Coronado PST
Rebel XT/XTi, DSI Pro (I & II), DSI, LPI, Electronic Eyepiece, Phillips SPC900NC
Tasco 60mm Refractors
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orenabah
member
Reged: 05/21/08
Posts: 88
Loc: Connecticut
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Actually, unless I was very off in viewing anything, both times I tried a Barlow (2x) it made the problem worse. Maybe it was too strong?
It looks like clear skies for tonight, so I'll go and try some of these suggestions that you kind folks have given.
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Celestron NexStar 130 SLT
Celestron NexImage
Zhumell 20x80 binos
Meade DSI pro
Panasonic DMC-TZ3
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Jerry3672
Vendor - Quantum Astronomy Products
Reged: 01/20/08
Posts: 295
Loc: Lexington NC
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Ore- My barlow does the same thing, it moves the focus point down close to the tube
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Meade LXD75-SN-8
C11
DSI Pro
Sony H7
Canon XSi 450D unmod
www.spike-a.com
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orenabah
member
Reged: 05/21/08
Posts: 88
Loc: Connecticut
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Yah, so I tried a few things last night. I grabbed a diagonal and tried it out. It had the reverse effect -- it just made Jupiter so huge it did not fit in the frame. Somehow I expected that  .
My scope seems to not have its own set of adjustment screws - just collimation screws, unless they are one and the same (excuse my n00biness).
But I found something interesting that I think ought to do the trick if I can fix it. Fully extended, my focusing tube measures 7 centimeters with the 2"-1.25" [stock] adapter attached. Without it, it's 5 centimeters. I'm guessing that if I can find one any smaller, it would do the trick.
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Celestron NexStar 130 SLT
Celestron NexImage
Zhumell 20x80 binos
Meade DSI pro
Panasonic DMC-TZ3
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Jerry3672
Vendor - Quantum Astronomy Products
Reged: 01/20/08
Posts: 295
Loc: Lexington NC
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Orenabah- If you can take the 2-1.25 adapter out and just hold it by hand to see if it will focus, then you could take a look at a flush mount adapter. Here is one:
http://starizona.com/acb/Feathertouch-Focuser-Low-Profile-2-125-Adapter-P2516C653.aspx
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Meade LXD75-SN-8
C11
DSI Pro
Sony H7
Canon XSi 450D unmod
www.spike-a.com
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