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Posts Made By: Larry Thaxton

September 29, 2017 09:05 PM Forum: Takahashi

FCT-125 First Light with FC-125

Posted By Larry Thaxton

This summer has been mostly a bust for astronomy due to the huge number of wild fires and subsequent smoke. I was very reluctant to take the scopes out as there was so much ash in the air I feared damaging the optics. But that does not mean things have been stagnant. A friend in Japan contacted me to let me know he had found a very rare scope – a Takahashi FCT-125. I have never seen one, nor heard of anyone using one so it was a huge find.


Two nights back I decided to give it a try so I took the FC-125 off of the HGM-200 and mounted the FCT. Right out of the box, and with essentially no cool-down it was giving great images of the Moon. Very sharp and contrasty. I was actually shocked at how good the image was, though I do not know why. To check for color correction I ran the image in and out of both sides of focus – nothing! Obviously in-focus was totally color free. I also moved the image around the field of view to see if there was significant field curvature- nothing noticeable. What was noticeable was the incredibly shallow depth of focus – at f/5.6 you had to be dead on and the slightest movement of the focus knob meant the difference between in-focus and out of focus. But the big focuser on the FCT is smooth and precise and focusing was a cinch.

Saturn was just below the Moon so I pointed the FCT at it. The image scale was pretty small, but it was a nice image, far better than the 16” R-C at “Hopservatory” we visited a week ago. I tried all the eyepieces I had, but the shortest was a Pentax XW 5mm which ran at 140x. I did not have the HGM tracking which was a mistake. Next time!

Out of curiosity I changed scopes and spent some time with the FC-125 for comparison. The image scale of the longer focal length scope was more pleasing, but sharpness on the Moon was a push. Reaching focus was easier in the FC, but once reached you would be hard pressed to tell any difference. The FC is really well corrected for color - I racked the focuser in and out and could just tease a slight, and I mean slight, fringe of faint yellow/green on one side of focus and faint purple on the other. I had to work to see the colors they were so slight. No color at all in-focus. Nada.

The Moon looked great in everything I threw at it up to the 5mm XW at 200x. The 6mm Delos was very sharp, nearly as sharp as the Pentax . Turning to Saturn I was immediately struck by the sharpness of the image. It would be hard to say it was sharper than the FCT, but the image scale and ease of focusing certainly made it appear more detailed. Cloud belts on the globe, Cassini’s, etc were all clear as was Titan. Titan was also clear in the FCT so, again, a longer test with the mount drives on is in order.

Hercules was nicely placed so I swung the FC to M13. It never ceases to amaze me how the superior contrast of refractors seemed to allow them to perform above their actual aperture – M13 was wonderful! Dim, but clearly a ball of pinpoint start. It looked better than any 8” SCT I have ever seen M13 through. Great image!




March 11, 2018 08:44 PM Forum: How to make AstroMart BETTER!! My idea is.....

Re: NEW ASTROMART - Requires your feedback!

Posted By Larry Thaxton

I took a look and liked it a lot. Clean, simple layout. I looked at one of the classifieds (maybe the only one currently), an article or two and thought everything looked fine. Looking forward to more!

July 7, 2002 06:06 AM Forum: Equipment Talk

Refractor lens recoating

Posted By Larry Thaxton

Hi Gerry,

E-mail Barry at D&G Optical. He should be able to either help or point you to a coating service:

info@dgoptical.com

July 10, 2002 10:03 PM Forum: Equipment Talk

Meade apos

Posted By Larry Thaxton

Hi Ibrahim,

While I can not answer all the questions you have asked, I do have an early Meade 127ED APO on the original 600 series mount. The scope has been a wonderful performer on the moon, planets and the brighter deep sky objects. I am no expert at the star test but I do see a difference inside and outside of focus which appears to be a bit of spherical abberation. I do not notice any degrading of the image however. I have compared it to several scopes: an excellent 6" F/8 newtonian, a superb 4" Showa flourite and a great 6" D&G F/15. The Meade matched or slightly exceeded the 6" newtonian, bested the 4" flourite on planetary detail and lost out in overall detail to the D&G. The Meade exhibited essentially no color while there was a bit in the D&G, the actual images were equally as sharp, the D&G just "out-horsepowered" it. I have been very pleased with the Meade APO and with the goto feature of the mount. I have had the opportunity to view through several highly touted scopes- a 7" APM triplet-APO, 130 and 155 AP's and Tak 4" APOs. The Meade has held it's own against all of them within the limits of it's aperature.

September 4, 2002 10:22 PM Forum: Equipment Talk

Mount for large f/15 refractor

Posted By Larry Thaxton

Hi Morgan,

I had a D&G 6" F/15 on a Meade DS-16 mount with a heavy wood tripod and it was an excellent combination. The mount was on rollers and the 6" was almost a "quick grab scope" as I just rolled the mount out of the garage, dropped the tube into the rings and began observing.

I am planning to mount my 8" F/12 D&G on a Parallax HD150/200 mount. It will be a bit more of a beast to set up but worth it!

September 12, 2002 05:37 AM Forum: Telescope Making

September 24, 2002 07:02 AM Forum: Equipment Talk

October 27, 2002 11:27 AM Forum: Equipment Talk

December 10, 2002 06:47 AM Forum: Equipment Talk

How do I remove a Telrad base?

Posted By Larry Thaxton

Hi David,

If you are near a Lowes or Home Depot buy a bottle of "GOO GONE" made by Magic America Corporation. It is a liquid that dissolves gum, masking tape adhesive, glue, grease and just about anything tacky. I have used it to remove masking tape residue that was untouchable by anything else from an old fiberglas tube as well as two-sided tape residue from a couple of tubes. It did the job easily and there was no damage or discoloration to the tube finish. I do not work for them, I just highly recommend this product.

February 2, 2003 05:34 AM Forum: Equipment Talk

4" refractor to 5" refractor

Posted By Larry Thaxton

Hi Don,

I owned a Meade 5" APO and a C8 at the same time and had a chance to compare them on a number of nights. I also has a 4" Showa flourite with an excellent (documented via optical testing) objective lens. The Meade was an excellent performer and showed more planetary detail than the Showa. It seemed to me that the extra inch of an excellent 5" beats a superb 4" even though the 4" lens was better optically. The 8" had a brighter image on all planetary objects and showed a wealth of detail. The 5" was clearly sharper in rendering the planets (and the 8" was dead on in collimation) but provided less information and a dimmer image.

I own a TAk FC76 which is an amazing little scope. If the FS 128 performs as well, it would be interesting to pit the 5" Meade APO against it. The Tak would have better build quality for sure but performance would likely be quite close. A friend of mine with a ton of experience and a expert "refractor man" told me over the years he owned several 5" Meade APOs and they matched every high 5" APO quite nicely- at a substantially reduced price.

Having said all that, I personally would not give up the two nice scopes you own for one 5" of any manufacturer until I had a chance to look through the 5" and see what it would do. My 5" did not "blow away" the C8 though it was sharper. You have a lot of versatility in the setup you now have.

Take a look at Cloudy nioghts article on the 5" APO shootout (Meade v Tak v AP). If you can not find it, e-mail me and I will send a copy.

Larry

ltha379@aol.com