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Starlight Instruments FeatherTouch Focuser

Posted by Paul Atkinson   05/27/2004 07:00AM

Starlight Instruments FeatherTouch Focuser
FeatherTouch Focusers
By
Paul Atkinson

It seems these days that critical focus plays such an important role in astronomy. From visual work, to photo, to CCD, getting accurate focus has become a major goal of everyone. There is nothing as annoying as tweaking a poorly designed focus knob back and forth trying to find that “sweet” spot for the application you are working on, only to be frustrated time and time again.

In the old days there was basically only one option. That was the focuser or focus mechanism that came with the scope. Some were rather crude. Others only slightly better. After a while somebody noticed a need for alternative ways to achieve good focus. With the boom in amateur astronomy a number of after market products slowly began to appear. Companies such as JMI paved the way with their NGF series focusers. Another major factor was the advent of the internet. It seems almost overnight this medium provided inventive amateurs a cost effective avenue of bringing their product to market. Now a multitude of options are available from manual crayford style focusers on up to high tech temperature compensating computer driven models. So which one is best. Well I can’t answer that but I can tell you about my experience using one particular model, the Starlight Instruments Feather Touch. During my review I may refer to it as the “FT” so that I don’t have to continually write Feather Touch or focuser.

I have a C14 and got tired of using the focus knob never quite obtaining the focus I’d want. If you are familiar with SCT’s you know that using this method focus is achieved the mirror moving forward and back slightly each time your rotate the knob in either direction. Does it work? Yes. Is it best method? No. The next thing was to try a very popular after market Crayford style focuser that was motorized. I found this to be better but still not quite right. The problem was that I found that pushing the buttons I would sometimes run buy optimum focus and overshoot the desired stopping point. After using that for a while, I opted for one of the “newer” manual Crayford being offered a few of the dealers out there. Although they work rather well I was not overly impressed by the design, or the workmanship, which I will explain more about later.

Owning several high end refractors I craved the smooth focus that models such as the Televue, Takahashi, AP’s and TMB‘s offer, only on my C14. If you have ever used one of those scopes you know what I mean. They have a buttery smooth feel when you turn the focus wheel.. There is no jerking or tightness. It allows you to manually obtain an outstanding focus with instantaneous response in each direction without any image shift or degradation. Then I started hearing about a new focuser on the market called the FeatherTouch and decided to order one.

The Feather Touch model comes standard in anodized black. At one time, I believe you could get it in specialized colors but according to Werner Schmidt, the inventor, that option is no longer available. Several models and adapters are available for all types of scopes from Dobs to SCT’s, however, the combinations are too numerous to mention here. Many of the known dealers such as Anacortes offer most of the variations you‘ll need depending on your scope and you can find information on their websites. Thus began the odyssey of actually getting my hands on one.

Here is probably the only real complaint of my review. Several months earlier I had actually contemplated ordering a Feather Touch. However, when I contacted every online dealer that sold them (6 that I could find in my search), not one had them in stock! Being impatient in our “want it now“ world, I opted to try a new SCT crayford that was being advertised by William Optics and Apogee. Heck, I figured I’d save some money to boot. Both of these worked very well for the price but also seemed rather cheap in some respects. Having tried the Feather Touch on various scopes that other people owned, I just couldn‘t get it out of my mind. After a couple of months with the “other” model I decide to make the switch. Guess what? When I checked this time, it was exactly the same thing. NOBODY had them in stock. I found this to be very frustrating and a little annoying. Of course they all indicated they could order one but it would be several weeks before they had it. Instead, I decided to go right to Starlight Instruments and contacted them directly. Werner Schmidt, the owner, took time to answer all my questions and never seem impatient with my ramblings. He was a very pleasant person to chat with. However, when I went to order I found out that he did not take credit cards or Paypal. Again, a high level of frustration arose from this as now I had to get a check out and mail it. Mr. Schmidt also told me that it would be 1-2 weeks before it would be ready. I guess not even Starlight keeps them in stock. In any event, I figured this would still be quicker than a dealer. Note - This was several months ago and the situation could have changed.

The Feather Touch I ordered was $300 plus I needed a $45 adapter to make it work with my scope. Add shipping and I was looking at $355.00 total. Many out there may be gasping at that price but you shouldn’t be. Right out of the box you know the Feather Touch is special. Most in our hobby can instantly recognize quality machining and careful attention to detail. That is what I saw, a finely crafted accessory that reeked of high quality workmanship. It’s weight felt substantial in the hands. This made me feel very good. This made in the USA unit uses all hardened stainless steel, brass, and anodized aluminum. I felt like I was holding and looking at something worth the price I paid for it. Considering the glut of mass produced Asian products flooding our hobby, this can’t always be said anymore. In addition, having some machined products of my own on the market, I can honestly say that prices charged actually seem VERY reasonable for the product you are getting.

Speaking of Asian products. There are currently two models of SCT crayford (that I am aware of) being offered which are being made overseas. Without naming companies, I’d like to say that although both of them work fairly well, they are miles behind the Feather Touch in overall quality. Of course, they are also cheaper in price. With many this is a valid consideration in an already expensive hobby. However, I think the old adage you get what you pay for comes to mind.

As mentioned earlier the FT comes in a variety of configurations. The model I ordered has the 1.5” drawtube. This was the recommended model for SCT’s. There are shorter (0.8”) and longer (2.5”) depending on your need or the application you will be using it for. In addition, I needed a special adapter to allow me to use it in my scopes present configuration. Both elements weigh in at just under a total of 2 pounds. I believe it was about 21 oz. Based on a digital mail scale in my office. This is something to consider as it will factor into the balance of your scope once you ad a diagonal, ccd camera, or one of today’s larger EP designs. Although not overly heavy, it may impact a scope on a German Equatorial Mount or a DOB. Of course, the SCT model is slightly different, not needing the additional base plate that DOB’s and other scopes will need. I could not find a resource for this weight.

Once I attached to the scope I loved the look. This thing is just so cool. But what makes the FT so unique is the focus mechanism. It is actually designed to allow two different speeds with a 10:1 reduction. So what does that mean? What it means is that there is a larger course adjustment knob for making large shifts in focus, and an awesome second, smaller knob, that allows for very fine focus. The fine focus is travel is 0.070” per revolution. Small indeed. This is very desirable especially during visual work where you may be changing out several EP’s or achieving critical focus with a ccd camera. Currently each unit can hold a decent 5 pounds of gear, be it diagonal and EP or CCD camera’s. A small drawback to me was that the FT uses two screws to hold your diagonal in place instead of the new compression style design using the brass tension ring. In any event, at least both screws are nylon tipped to prevent marring of your diagonal or other surface.

How does it work? Well let me just say that it is the finest focus mechanism that I have ever used including the afore mentioned refractor designs. It is not buttery smooth, it is SILKY smooth which is even better. I can basically leave my C14 focus knob alone. Thus, I hardly ever have to actually move the mirror, something you must do to focus a SCT with its own focus mechanism. This is very important with an SCT for two reason. One, the less you move the mirror the longer an SCT is prevented from getting dreaded mirror flop. This happens when the spring inside an SCT that the mirror “rides” on begins to loose its, well, spring. Kind of like a shock on your car going bad. Thus the mirror starts to shift a little when the telescope is moved or pointed at a new object. This results in the constant need to refocus. Second, by leaving the mirror in place you achieve a much finer focus by the moving only the EP without moving anything else. Anyone that has ever had an SCT knows what I am talking about.

When focusing the thing I found I liked the most is that I could set the tension so that I could achieve focus with minimal effort. What I mean by this is that I barely have to turn the knob to get results. This ability to use a very gentle touch also means that the scope shakes less allowing you to see the object better. I found I got a razor sharp image time after time. I have used a Feather Touch on a Dob with equally impressive results.

Newer models of the FT have an internal brake. This internal brake is a screw on the bottom of the FT that you can tighten or loosen to get the desired amount of tension you want. Thus, depending on load, you can make sure that your diagonal, or ccd camera stays in place. There is no slippage that some of the other models, such as the cheaper Asian model I used, will allow. What I mean by that is that on the “other” model if I had my 31mm Nagler and 2” Everbrite in place and pointed the scope towards the zenith gravity tended to pull it out even with their version of a brake. This is where the term slippage comes from in this regards. This slippage would result in a loss of focus and frustration. This does not happen with the Feather Touch.

There are very few negatives. However, I’d like point out a couple of things I think would make it just a little better. I think an awesome addition would be a camera rotator adapter like many top end refractors have. This feature would allow you to change the position of your camera or EP without having to “loosen” the diagonal or accessory. Thus, there is less potential for dropping something in the dark, like your prized diagonal and EP, and it also makes for more enjoyable night not always having to move everything each time you change the OTA’s position. I also would like to see the carry weight increased. I think that 5 pounds, although adequate, is a little low. A Televue/AP 2” Diagonal and a Nagler 31 get close to that by themselves. Lastly, Starlight should incorporate the newer compression method of holding diagonals vs. the old screw method. Other than that… I’d have to think REAL hard to find anything to improve on.

In closing, I would highly recommend this accessory for ANY type of scope, including many refractors. This is something that I believe you can do, or that several APO makers such as AP and TMB are now offering as options. If you want the best there is, at a reasonable price, this is it.

Click here for more about the Starlight Instruments Feathertouch Focuser (there is more than one model), -Ed.