Posts Made By: Paul Gruener

Hi,
I have a Tak 1.25 prism diagonal and a standard TV 1.25 diagonal. While not an exact match to your question the info may be helpful. I have used both and compared them both on two scopes, an FS102 and a 7" Meade Mak. I have swapped them out back to back and used the same eyepieces. Overall the Tak diagonal is brighter but if I get my eye off axis there is false color. If find my TV provides more contrast and is not as sensitive to the placement of my eye in relation to the optical path. After trying each for a while I have settled on using the TV diagonal.

Good luck,
Paul G.

Thoughts on the Gemini GOTO with GM-8?

I am planning on getting a GM-8 and I find the Gemini an interesting option. I am wondering if anyone has any experience with the system?
Do you like it?
Have you had any problems?
Was it worth the extra money?

I live at the edge of a suburban area. The sky is not always very good where I live. Also, I do not often have a lot of time for observing or I am tired latter in the evening. I find the latter it gets at night the less successful I am at finding objects with my alt / az mount. I want to get a nice GEM mount and I am considering the goto on the GM-8. I have a FS102 refractor.

Thanks in advance for your help. Paul G.

Mounting a C 9.25 SCT to a standard GM-8 mount

Hi, I have a GM-8 with the standard saddle plate. How do I mount a Celestron 9.25? SCT OTA to my GM-8? Do I have to get the bigger saddle plate from the G-11 and use the D series components?

Also, I have the 11-pound counter weight (no 7 pound weight). Will I be ok with the 11-pound counter weight? I do not expect to mount anything but the finder, a diagonal, and an eyepiece on the OTA.

Thanks in advance for your help
Paul G.

Hi,
I have been involved with astronomy for a number of years and I am looking for a nice mid-sized scope, something in 5" range for occasional visual observations or a smaller refractor. From my somewhat light polluted skies I like to look at the moon, planets, double stars, clusters and what deep space objects I can muster. I have owned and enjoyed several Maksutovs up to 7" inches. I will not be able to afford another good 4" APO for a while so I have been thinking about the new improved Meade 125 ETX with the metal reinforced mount or a used 70-85mm refractor such as a Televue.

The questions:

When one factors in the central obstruction, will a smaller refractor show as much nebulosity and brightness in say M42 as the obstructed ETX125 or will the bigger mirror of the ETX still pull in more light?
With the addition of the metal reinforcement to the ETX125, is the mount now stable? I know it will not be like using my old GM8, but is the mount OK now for visual use up to say 200x?
Will a TV Pronto hold up to magnifications of 175x for planetary observations, or do you need to move up to the 76 or 85 APO TV scopes?

I am interested in first hand observations and experiences. I have read the reviews on Cloudy Nights and Scope Reviews. Thanks much in advance. Paul G.

Hi,
I have been involved with astronomy for a number of years and I am looking for a nice mid-sized scope, something in 5" range for occasional visual observations. From my somewhat light polluted skies I like to look at the moon, planets, double stars, clusters and what deep space objects I can muster. I have owned and enjoyed several Maksutovs up to 7" inches and a Takahashi FS102. I will not be able to afford another good 4" APO for a while, I am looking for something to hold me over for a while. In another post I outline that I am also considering a small TV refractor or a Meade ETX 125 with the improved mount. The new Meade LXD55 refractors are also an interesting option.

The questions:
I have owned and loved an FS102. The sharpness and contrast were stunning. I have not used an achromat such as the new Meade 5 and 6 inch LXD55s. Will there be a large difference in color correction? Will I hate it? Would I be better off with the 5" Maksutov or a small TV scope for what I like to look at?

Can the LXD55 mount deal well effectively with the 6" OTA or am I better off with the 5"?

I am interested in first hand observations and experiences. I have read the reviews on Cloudy Nights and Scope Reviews. Thanks much in advance. Paul G.

Hi all,
I have been observing for a few years now and I am a little stuck as to what to do next. Short history:
I have owned a 3.5” Mak, an LX-50 7” Mak, an LX-200 7” Mak; a Meade 102 ED “Apo” with an LXD500, a Tak FS102 and a GM8. In each case, I would start with something I could afford and keep upgrading. For example, I started with the ETX 90 and worked my way up to the LX200 7” Mak. On the refractor side, I started with the Meade 4” Apo (semi?) and then had a look through an FS102…

Last year the 7” LX200 and Tak went away when I purchased a fun car.

Santa brought me a nice 5” Mak so I could keep observing.

The 5” Mak has been good. While it does not show deep sky objects like my old 7-inch scopes, it does pretty well and is sharp on the planets and the moon. I like it and plan on keeping it. I was going to get another 7-inch Mak this fall, but then something happened: I had a good look through a 10” and a 13.5” Dob. Yikes! The sky was clear and steady, and we were away from most of the city lights. Objects such as M13, M92, M8, M57, M31, and the Double Cluster took on a completely new dimension. For those of you out there with big reflectors, I would guess this is nothing new.

Here is the challenge. There is very little of my yard that is flat. I usually have to adjust at least one tripod leg to get a mount level. The front yard (and darkest part of the sky) has a steep grade. I like having a driven mount so I can study objects; I am not a big fan of nudging a scope. I also like having setting circles to help me locate objects. I prefer GOTO because I think it is great fun and because I do not often have a great deal of time to observe. I would like to be able to take something with me to a darker site from time to time. I am not at all interested in astrophotography. I just love to observe.

What are some 10” reflectors that could work for me?

I have looked at the Orion 10” \ EQ-6 package and I am intrigued. The reviews I have read on the Dob version of this scope seem good, is there anything I am missing with the combination? Are the optics OK? For visual use, would the EQ-6 be OK? I think I would only add GOTO if I could not find things with the SCs and the finder.

I loved the GM-8 but I am guessing this mount would be too light for a 10” OTA. If I am not going to take pictures, could this combination work?

Clear skies!
Paul G.

I have a question about the in focus star image created by my ETX 125. The scope was new this holiday season and has the new UHTC coatings. I understand from reading posts on Weasner's ETX web site that it is not possible to judge the alignment of some Mak optics based on the out of focus star images. I have been concentrating on studying the star images of my scope when they are in focus. I have been looking at stars at or near the zenith on calm nights with stable optics. In each case, I attempt to put the source in the center of view.

In addition, I have been using a few Christmas tree ornaments mounted across the street on a power pole to try to create an artificial star. The results look consistent to me in all the eyepieces and with the different light sources. I have also tried flipping the mirror a few times and rotating the eyepieces to see if there were some other variable(s) affecting the image.

I have been using my:
15 mm TV Plossl 126x
8mm TV Plossl 237x
5mm Takahashi LE ED 380x

What I see is a round tight star image with a bright first diffraction ring. Next, several faint diffraction rings are visible. If the light source is a star, I will see one or two rings. If the source is an artificial star, lit by the bright sun, I see more rings.

Here is where things get interesting… The diffraction rings in focus do not make a complete circle around the star point in the middle. The rings cover about 45% of the area around the point and they are visible across the top half of the star. The bottom 55% of the image has little or no diffraction rings. If rings show up on the bottom half of the image, they are very, very dim.

I see a consistent pattern of incomplete (weak) or non-existent diffraction rings in a sweep clockwise from three o’clock to ten o’clock around the focused star image.

For a practical example, I have been able to split the left pair of stars in the Double-Double, but I struggle to split the right pair very cleanly using my 8 mm TV EP.

Is my in focus image correct for an ETX 125? What do you think?

Many thanks in advance for any analysis you can provide.
Sincerely, Paul G.

Hi,
I am working on building a portable 18 volt DC power supply for my LX200 (classic). My question is this: If I have a 12 volt battery that is rated at 12 amps and if I put it in series with a 6 volt battery that is rated at 4 amps, will the extra draw \ capacity of the 12 volt battery cause any problems for the 6 volt battery?

Thanks in advance for any help or suggestions you are able to provide.

Regards, Paul G.
Wisconsin

Hi everyone,
I have an LX200 Classic 7" Mak. Recently I added a JMI NGF SE to the scope. I have always used a 1.25" diagonal and eyepieces. I would like to add a 2" diagonal to eek out a little more field of view from my f15 optics.
My challenge is space. With the focuser attached to the back of the OTA there is not much space left between the back of the OTA and the fork base. When I take some rough measurements, I find there is 80mm of space with the focuser fully retracted and 65mm of space with the focuser fully extended. I would like to find a nice 2" diagonal that will fit between the focuser and the base when the focuser is fully extended.

Do you have any suggestions?
Thanks in advance, Paul G.
Wisconsin

Hi,
I am the new owner of an Intes Micro 7" f15 Maksutov OTA and a medium sized Losmandy mount (GM100). I have had a little experience with GEMs, my old GM-8 held a 4" f8 refractor. Compared to my current OTA, the 4" refractor had a very wide field and I found it very easy to locate objects.

With the new tripod fully extended and the OTA pointed high in the sky, I find myself in an uncomfortable position and very low to the ground looking through the finder. The combination of the OTA's narrow FOV and the stock 8*50 straight through finder makes locating objects a challenge.

I am going to make a few additions to my telescope. First, I plan to acquire a 2" EP so I can see more then a .6 degree view. Secondly, I would like to get a nice right angle finder.

Please recommend a high quality right angle finder. I would like something about 50mm in diameter that will fit my 60mm finder bracket. Magnification of 8x or 10x is fine.

I have seen a few finders with a prism that project a corrected view. If I purchase a prism finder, will I loose some image brightness making it harder to find dim objects? Does the prism reduce the image quality?

Thanks in advance,
Paul G.