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Posts Made By: David Keller

December 23, 2002 11:59 AM Forum: CCD Imaging and Processing/Solar System

Saturn back on 11/13/2002

Posted By David Keller

Since the weather in Indiana has only cooperated once since the end of October, I thought I'd post this last vestage of good seeing in Indiana from back on 11-13-2002.

This Saturn image was at 6:30 am using a Philips Vesta Pro 690K and a Televue 2.5X Powermate attached to a 12.5" Portaball. Tracking was achieved with a Tom O. single axis platform. Recorded an avi file at full 640X480, 30 fps, 1/33-second exposure, and manual gain of around 70-80% for a total of 1041 frames. Picture is the result of the 492 best frames picked using Avi2Bmp, stacked and processed with dyadic filter in Registax. It was necessary to make four individual stacks; three of 120 frames and one of 132 frames. Each stack then required boosting color saturation in Adobe prior to final stacking in Registax. For some reason, Registax partially negated the color even when color processing mode was used; thus, boosting the color in photoshop on the individual stacks was required. Final processing in Adobe Photoshop 5.0 LE still required more color saturation and a pinch of Gaussian blur to quench graininess from Registax. Sky stability was pretty good for Indiana in order to use this high of a percentage of frames; normally can only use about 20%.

Dave Keller

January 19, 2003 09:55 AM Forum: CCD Imaging and Processing/Solar System

Softwere for Realigning RGB?

Posted By David Keller

Hey gang,

I've been doing planetary and lunar photography with a Philips Vesta Pro for a while and am getting faint blue/blue-green color error along one side of the planetary/lunar disk's limb. The telescopes are Newtonian Reflectors and SCTs so we can't blame this on color abberation from the telescope itself (always properly collimated before use). This problem also happens when I don't use the Televue Powermates so it is not a color error from Barlowing. No eyepiece projection is being used either. My conclusion is that it is an abberation imparted by the camera itself. Some of you have advised in the past that the picture needs to be broken down into it's RGB components and then realigned. I recently saw some examples of "before and after" RGB realignment over on the QCUIAG Yahoo group that matches the exact problem I'm having.

The question is "Which software programs have the ability to break a color image into RGB components and then realign them?"

Do I need one software program to break the image into RGB and then go into something like Astrostack or Registax to realign/restack?

Give me a variety of different programs that can do this. I will eventually move on to using a true Astrophotography CCD camera (SBIG or Starlight Xpress) so I want to plan ahead in terms of handling their requirements as well.

Dave Keller

September 16, 2003 09:29 AM Forum: Insects - Flowers and Other Small Stuff - Photos

Black & Yellow Argiope

Posted By David Keller

Here is a Black & Yellow Argiope Orb Weaving Spider I found by the side of my house. These spiders are often called "banana" or "garden" spiders. It was very difficult to achieve focus in "automatic" mode because the camera was using the bricks, not the spider. Need to learn manual focus mode to zoom in closer and get a sharper image. Camera was a Canon Powershot G2.

Dave Keller

October 10, 2003 03:03 PM Forum: DVDs and Music and Books That You Recommend


Posted By David Keller

Just had to beat Herb to it on claiming Message #200.

Dave Keller

August 10, 2002 12:57 PM Forum: Equipment Talk

Premium Dob or Not?

Posted By David Keller


I've read everybody else's responses before posting and will say that if you are already committed to purchasing a scope, definitely follow the recommendation on visiting the starparties. Look through everything you can and go on several occasions in case seeing conditions aren't good on one or more nights. You will also get to see a greater variety of eyepieces that way (maybe even a binoviewer).

I am not trying to discourage you when saying this but you must determine how much of this hobby you can afford. Raising three kids is extremely expensive. It is probably better to go with a cheaper mass-produced scope first before you get in over your head financially. This hobby can be extremely addicting and the next thing you know, your wife will say "Where did the $5000 in the savings account go" while she's warming up the frying pan on your head .

Another reason to "go cheaper" on the first scope is to find out if it survives the child destruction factor. I personally don't have any kids but one day, my older sister brought her ~ 3 year old son over to the apartment. I had lived there about 4 years and this kid managed to lay down as much damage in one day as I had in the whole four years. Given that kind of scenario, I would never buy a premium scope of any kind only to see it get trashed in one day.

Dave Keller

August 26, 2002 06:05 AM Forum: Equipment Talk

6 inch f/5 problems

Posted By David Keller

I'd have to see the star test "live in color" to be certain but it sounds like your mirror has either a turned-down edge (TDE) or severe spherical abberation (maybe both?). Make a mask with a 5" o.d. hole in it and place that over the front of your scope. Rerun star collimation and star testing after the scope has reached thermal equilibrium. If the star test cleans-up, the problem is TDE. If the star test remains cruddy, it's probably severe spherical abberation. You will likely need to replace the mirror if I'm correct. It's not worth the money to refigure a 6" mirror.


September 24, 2002 09:49 PM Forum: Equipment Talk

Too Many Telescopes

Posted By David Keller

Well, I did see in the rest of the thread that you like to do Lunar and Planetary viewing. The difficult part for us in making recommendations is that there are always subtle issues that attract us to the scopes we collect/use.

I'll put the choice like this: If the above collection were all mine and I was a Lunar and Planetary buff, I'd sell everything. The Questar is probably best suited for Lunar and Planetary but it is a well known fact that these scopes almost never reach thermal equilibrium (probably will change with the new Titanium Questar unit). Take the money reaped from the sales and get a Portaball 8" and 12.5". The 8" does superb planetary work, touches on deep space, and you can always sit down and be comfortable with it. The 12.5" is even better on Planetary and goes a good step deeper into deep space at the same time. If I had to go with only one of the Portaballs, it would be the 8" for sit-down purposes.


September 29, 2002 08:36 AM Forum: Celestron

C-14 or Meade 14" with UHTC Group???

Posted By David Keller

Jeff and Bruce already pointed-out that the Meade 14" is not available yet. Bruce pointed out the Fastar option on the Celestron as being a plus.

The only other advice I can give is that you should not be "first in-line" to buy a new product. Celestron had their bugs with the Nexstar GPS line. I think everything has been resolved except for the software/hardware being ~ 15° off on pointing to the first alignment star. Meade still has a way to go in ironing out the LX200GPS system. Thus, let everybody else be the beta tester and wait for their reports. At the same time, see if anybody else buys the Meade 14" and lives near you. Try to get a view before purchasing. About the only way you might be able to do a side-by-side comparison is at a large starparty some time next year.


October 1, 2002 07:17 AM Forum: Celestron

Is Celestron the dumbest company around?

Posted By David Keller

Well, Celestron probably doesn't take credit cards in order to avoid paying the credit card transaction fee (something like 3.5% of total sale value?). I do agree that in this day and age, this choice is not customer friendly and probably has had a negative impact on sales.

As for the leg spreader replacement, have you considered the Star Tek 3-N-1 Leg Spreader/Accessory Tray? I have one of these on my Meade field tripod and it is excellent. The tray is made of aluminum and when you fold the tripod up, there is a handle built into the tray which makes carrying easier. Astromart sells these trays. The Celestron version is Part# ST0003 and goes for $124.00.


November 15, 2002 06:09 AM Forum: Equipment Talk

Buy New 24mm Panoptic?

Posted By David Keller

It's been too cloudy here in Indianapolis to do thorough testing but brief gaps in the clouds indicated this is an excellent eyepiece. Eye relief didn't seem much different than the 19 mm Panoptic but again, viewing was too brief to concentrate on that issue.

One guy in our local astronomy club brought his Nexstar 11GPS. Brief testing with the factory 1.25" prism diagonal caused noticeable vignetting (probably narrowed to ~ 60°). Thus, you may need to pay careful attention to the diagonal used with this eyepiece. I haven't tested this eyepiece on my SCTs or refractors yet to determine if a 1.25" mirror diagonal such as the Televue Everbrite doesn't cause vignetting.