New Feather Touch .

[brian nordstrom]

:D Hi all , I finally got around to fitting my new FT 10-1 micro focuser onto my sweet C9.25 .
Its typical FT quality that is , smooth , weighty , so very well made and sexy .

I have only had it out once so far the other night , but what I found was that its a beautiful bit of kit and at 150x I could not see any image shift when viewing Jupiter turning the fine knob a few turns in and out either side of perfect focus .
On that when in perfect focus using the fine knob this C9.25 performs brilliantly , I am a happy camper .

Brian.

[Amaranthus]

Nice Brian! I've been thinking of getting one of these for my 8SE - was it easy to fit? Where did you get it?

[Larryp]

Nice, Brian!

[Steffen]

Congrats, a fine-focus knob seems like a worthwhile upgrade, especially a well-made one.

However, I didn't think image shift in Cassegrains is to blame on the focus knob? I thought that was an unavoidable consequence of moving the primary mirror for focussing, and tilting it slightly in the process.

Cheers
Steffen.

[FlashDrive]

Nice addition there Brian .. ever so smooth aren't they. :thumbsup:

Col ..

[traveller]

Nice one Brian,
Is there a focus lock or similar function? Or does the focuser simply holds the focus?
The reason I am asking is I am thinking of getting one for my C8 and wonder if I should get that or the moonlite unit.
Thanks!
Bo

[The_bluester]

I have one on my 925 as well and it is beautifully smooth. It still shows just sniff of image shift. I think the reduction is because you can move the focus much more slowly so the friction on the system (the grease ironically enough) is less of an issue.

No focus lock involved but it does not seem inclined to move. Fitment was really easy, 5 minutes territory.

My only gripe is that it seems that you can induce image shift by pushing sideways on the FT assembly, but I never did do the same test on the original focus knob. Not a big issue.

[brian nordstrom]

:thanx: Paul you covered the questions well and they are a great scope . aint they ? .

Barry , I got this one 2nd hand , brand new from a fellow IIS'r for $150 , yes a steal .

Laurie , thanks mate .

Stefan , I found that my scope has basically zero image shift , its a good one and there are lots of good sites on the web detailing how to improve the standard focusing mechanism , its not a big job , but as I say mine is a very nice OTA .

Brian.

[brian nordstrom]

:thumbsup: You bet , old mate .
Brian.

[Camelopardalis]

Congrats Brian, they are a quality piece for sure :thumbsup:

For those that do suffer some mirror shift during focussing, the "trick" to it is always focussing against gravity, i.e. so that your final move of the focus knob is pushing the mirror up...on Celestron SCTs, this is anti-clockwise. The micro focuser doesn't eliminate that per se, it just allows you to get closer to perfect focus with the first movement :)

[The_bluester]

That is what I found. I always try to come to focus against gravity. I am pretty sure that the reduction in visible image shift I have seen in my scope (Which is really not very noticeable in the first case, it only becomes obvious at high magnifications) really is because you can much more easily make the last focus movements very slowly.

It may even relate to the sideways pressure issue I mentioned. trying to get the focus "Just so" at high power with the original focus knob was a matter of pinching the knob between two fingers to try to move it very small amounts, which would make it quite easy to apply a little sideways pressure at the same time without meaning to. with the FT on there you can easily dial it in with a more relaxed hand.

Now I just need to find some more time in post fire recovery to actually get it out under the sky! My weekend are pretty busy and I am pretty worn out by the end of the day most times.