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Posts Made By: John Theodossy

July 17, 2002 02:01 PM Forum: Equipment Talk

LX200 GPS 7"Mak-Cass vs 8"SCT

Posted By John Theodossy

I know this topic has come up before but couldn't find the string. I am interested in your opinions on the PRACTICAL differences between these 2 scopes.

Is the light grasp close or is the 8" clearly better?
Is the contrast close or is the 7" clearly better?
Does the net result of the above 2 differences make them the same at the eyepiece, or is one clearly superior in real life?
Is the cool down time of the 7" Mak really excessive relative to the SCT?
Is collimation a significant problem with the SCT?
Does the f14 of the Mak make it usless for photography?

And any other PRACTICAL, "at the eyepiece" differences you can think of?

Thanks
John

August 26, 2002 08:31 AM Forum: Off Topic Discussions

How do I post a picture on an Ad?

Posted By John Theodossy

How do I post a photo of an item I want to sell in the classified area? I did not see a way to do it from the "place ad link".

Thanks
John

December 23, 2002 11:50 PM Forum: CCD Imaging and Processing/Solar System

Saturn Season

Posted By John Theodossy

My best to date. Thanks to all for the inspiration and Merry Christmas.

Any comments appreciated

Acquisition: Canon ZR50 DV camera coupled afocally to 8" Meade LX200GPS. 20mm Meade series 4000 eyepiece. Optical zoom to desired image scale. 25s @ 30fps, shutter speed @ 1/60. 12/22/02, 0700 UT

Processing:
1. AVI downloaded and converted to BMP with AVI2BMP.
2. BMP loaded into Registax. Registered, aligned and stacked in Registax (best 296 frames out of 750 stacked).
3. Wavelet processing to my eye in Registax.
4. Curves adjusted to darken midtones, despeckle filter and slight unsharp mask in Photoshop. No color adjustments were made.

John

January 13, 2003 12:07 AM Forum: Equipment Talk

Re: Public observing and expensive equipment

Posted By John Theodossy

In my opinion the fault is 100% with the parents. As the father of a 6 year old boy, I can attest to the somewhat spastic nature Dan desribed. However, I leave my scopes setup in the "public" areas of the house and he was taught not to touch any parts unless Dad is there and said it's OK. When he comes out to view with me (whether in the backyard or at a public session) I watch him very closely to avoid any mishaps. Young kids do forget and get excited so I make sure I am extra alert to "help" him do the right thing.

The signed statement may be overkill, but a general comment (or sign at the entrance or parking area) to guest attendees of a public viewing reminding everyone of the "rules" may be enough keep less attentive parents a little more on guard. Something simple like, "No running, yelling, or touching equipment without permission" will probably be good enough for most.

Hopefully your "little rebels" will not return.

John

January 30, 2003 01:35 PM Forum: CCD Imaging and Processing/Solar System

Question on bit depth

Posted By John Theodossy

I understand the meaning of bit depth but am having trouble visualizing the effects on an image and have a couple of questions.

1. Can you obtain a greater bit depth by combining images of different lengths? For example if I use an 8 bit camera (e.g. SAC8) and combine 2 exposures of say 30 and 60 seconds will I have the equivalent of a single 16 bit image?

2. Is the "dynamic range" of an imaging device synonomous with its bit depth, or are there other factors that play into the dynamic range.

In the background of these questions is that I am contemplating several entry level devices and do not want to save a few bucks now only to find out that I want more out of the device after a few uses. I am thinking about the SAC 8 and Starlight xpress cameras (5 and 7 series). Any thoughts on these is also appreciated.

Thanks everyone.

John

February 17, 2003 10:40 AM Forum: Pictures of Me and My Telescope and........

Future amateur astronomer.

Posted By John Theodossy

Here's one of my son checking out jupiter a few nights ago.

John

March 11, 2003 05:18 PM Forum: Equipment Talk

Meade 4504 tripod/mount?

Posted By John Theodossy

Can anyone tell me anything about the 4504 mount? Is it roughly the
equivalent of an EQ1, or EQ2 or what.

Here is why I ask. Considering moving my ETX125 from the fork mount
to a GEM, but am trying to maintain Autostar usability. I would also
then be able to use my ST80 on the same mount. I am familiar with
the DIY mods on the web, but thought it would be easiier to get an
already compatible mount if available. I do not want to get a mount
that is not sufficient or only marginal to support the ETX125. I
know the LXD55 is far superior, but also way more costly. I have
occasionaly seen the 4504 on e-bay for less than $200.

Any thoughts, insights appreciated.

Thanks.

John

March 22, 2003 11:30 AM Forum: Equipment Talk

Mid-level refractors question

Posted By John Theodossy

I am looking at upgrading a generic ST80 to a mid-level short focal length refractor. I want to stay in the $3-600 range and also want to keep the scope fairly small to allow piggy-backing on an 8"LX200 as well as a quickie scope. I am interested in knowing what everyone thinks of the following compared to one another:

1. Stellarvue A1010 (Nighthawk)
2. WO Megrez 80
3. Televue Pronto/Ranger/76

The Televue option I am hesitant about as the aperature is less and am concerned about paying for a "label" without any real/practical performance edge.

So can anyone who has used any or multiple of these scopes give me some pointers? Also are there other options in this class of scope I have overlooked?

Intended use for the scope is as a quicke grab and go as well as wide field viewing piggy-backed on the LX200. I am also just starting to venture into imaging and this will likely be the initial scope I use with the imager.

Thanks all.

John

April 13, 2003 01:02 AM Forum: Equipment Talk

Adapter plate for EQ3, where?

Posted By John Theodossy

Want to mount an ST80 to an EQ3/Astroview mount. However, the spacing of the holes in the mount are farther apart than the ST80 tube is long. I know the mount is designed to have the tube rings directly couple to the mount rather than using a saddle plate/dovetail, but I don't see how this will happen given the situation. Orion used to sell Adapter plates for these mounts that had a 1/4-20 screw to allow mounting a camera, but these are no longer on their website (this would work as the ST80 has a mounting block).

Any ideas on where to get an adaptor plate, or other suggestions; or am I going to have to get out my tools and rig something?

Thanks
John

April 27, 2003 10:36 PM Forum: Film Astrophotography - Imaging and Processing

Suggestions for medium format film

Posted By John Theodossy

I am borrowing my brother-in-law's Yashica TLR for a camping trip next month and am looking for what kind of 120 film folks are using. For 35mm I have mostly used Kodak Max 800 and Royal Gold 400 (depending on what I could find and my mood). What do you medium format gurus suggest?

Thanks
John