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My old Win 7 box has died. It used lazyfocus.dll to drive the motorized focusser. The new box has Win 10 Pro and most everything (TheSky, MaximDL, LesveDome, SX cameras, etc) now works after some re-installation and re-configuration. The focusser steadfastly refuses to be driven by software. The Moonlite PRO ASCOM driver supposedly works as a LazyFocus driver but doesn't. Everything I have tried so far to install the old DLL has failed. Has anyone managed to get LazyFocus to work under Win 10? If so, how? Otherwise it looks like new hardware will have to be bought and got working. Thanks for any help. Paul

I believe I've landed in stump-land with a new imaging setup I'm putting together. In a nutshell: dialling in proper backfocus for my reducer causes the focuser to lose inward travel. In depth: I used the classic "look at the stars in the corners and add shims until they no longer radiate" and I'm very close to getting it perfect (<1mm). Trouble is, as I've increased the distance between sensor and reducer, the focuser (situated between scope and reducer) has had to move ever more inward to achieve focus. This to the point that I now have no more inward travel available and cannot achieve proper focus. I'd massively appreciate any ideas, thoughts, opinions or guidance. _ Image train is: FS-60CB ⇢ CAA (TKA21200) ⇢ Reducer (TKA20580B) ⇢ Adapter to M48 ⇢ OAG ⇢ Filter Slider ⇢ Shims ⇢ Camera

Hello everyone. Bit of a niche request for my first post, but is anyone using the ZWO EAF focuser on the standard Crayford type 150/750 Sky-Watcher Newtonian? The focuser is stated as being compatible only with Sky-Watcher's astrophotography OTAs with their dual-speed focuser, but I can't see why that is except perhaps that ZWO assume you wouldn't do imaging with the standard tube - whereas it works fine with my Nikon D750. I'm intending to get one but seeking reassurance it will work. I've seen this video: it's on a bigger OTA by the looks of it, but the focuser looks the same as mine (in French, but very clear even if you don't speak it):

Hello stargazers, I am using a Newtonian telescope (114mm/900mm) that has a 0.965" (24.5mm) focuser. My eyepieces are all 1.25" (31.8mm), so I use an adapter to make them fit. Yet, because the adapter adds distance between the eyepiece and the primary objective, does using an eyepiece adapter affect the way that my focuser works? Thank you for your advice.

Hi! Have anyone tried to make a DIY version of hand controller for zwo eaf focuser? Or tried measuring what is the output of the controller? I want to print a hand controller +battery case all in one but unfortunately do not have the controller to check what needs to be outputted thru connector. I assume it will be pretty basic like shortening contact but maybe someone has already checked Thanks for looking!

Hi, I have changed the focuser on my newtonian but its too short. I realise that I can just add an extension tube to it but I’m not sure if that is the best solution. I also seem to have have a stray light problem (I’m getting a hazy image on a 5mm eyepiece). A third problem is that I find it quite cumbersome that the focuser has to stick out so far (155mm+eyepiece). I wonder if I might solve the stay light problem by extending the main telescope tube instead of the focuser and therefore getting the eyepiece closer to the secondary. And also maintain more precision in the focuser by not extending it. As it stands the focuser would have to come out 265mm from the centre of the secondary mirror in order to focus. The secondary is 50mm wide. From primary to secondary is 950mm approx.. The primary is 200mm Thanks for reading. Any advice will be much appreciated.

The focuser on my SkyWatcher 150i is a basic rack-and-pinion, unsurprising for the price point, but sometimes a bit of a pain to control finely enough. I’m not looking to spend any serious money upgrading it, but I did want to see what I could tweak. The first thing I did was to slacken off (slightly) the screws holding the plate against the spindle, as the operation was very tight when new – that helped a bit (and I think that without doing this first, the “friction fit” approach described below wouldn’t have worked). I will eventually get around to taking it all off as per AstroBaby's tune-up. Improving the fine control without a major change means doing something with the focusing knobs – they’re quite small, so the effective “gearing ratio” when you operate them is on the harsh side. Some folk have described fitting larger diameter replacements, either bought or made, and even using ones with a planetary-style mechanism to achieve a reduction in the ratio. I didn’t fancy this, as I couldn’t see how the existing knobs were attached to the spindle without trying to prise them apart (possibly terminally). The other option is to increase the effective diameter of the existing knobs, for which purpose a clothes peg is apparently quite popular, but I’ve also come across descriptions of chop sticks inserted into holes drilled at intervals into the circumference, and punctured lids from peanut butter jars. I wanted something that was cheap, relatively tidy and non-destructive. The answer seemed to be some sort of thick sleeve that I could fit over the knob. It would need to be a tight fit so as not to slip in use, to be not so large as to foul against either the focuser tube or the main OTA, and to be thick enough that it didn’t flex sideways when grasped. I thought I might find some larger rubber washers that would do the job, but none were thick enough to be rigid in use. However, a bit of searching found these spacers that are apparently used in vehicle shock absorbers. My calipers said the diameter of the focuser knobs was around 29.5mm, and the nearest spacers that were available had an internal hole 30mm and outside diameter 60mm. I ordered one that was 10mm thick, not quite as deep as the knobs, but which allowed a bit more space on the inside edge for free operation. I’d hoped the internal hole might be a but undersized when it arrived but it was spot on, so I wound five or six turns of masking tape around the knob first. To avoid taking the tape off when fitting the spacer, I positioned one side first and stretched it across the face as I pushed. When it’s flush with the knob’s outer face, it’s just clear of the focuser body and OTA. There might be enough room to stick some kind of friction surface around the outside to improve the grip, but I don’t think it’s going to be necessary. I decided to do only the one knob, so I now have a very Noddy “dual speed” affair. Because the clearances around the fitted spacer are quite tight, it’s worth checking the positioning of the spindle in the focuser body first – mine was fractionally off centre, so there was more room one side than the other (assuming you have no preference).

Hi Everyone, Would someone happen to have STL files for a simple printable Crayford/R&P focuser please?

Hi All I am starting this as a baseline to find out Cons and Pros for the difference, between standard focuser and all the way to the electronic top? up to max £3k. I mean : practical : i would like not to worry about rotating and focusing at all., so paying big bucks will give me this reassurance? - i guess? yes? - one focuser for all!!!! I have a short list for all: refractor /reflectors,/newtons Moonlight FT, ASA AAf3", RotoFoc 3, Nitecrawler 3, Optec TFT-53, Integra 85, Finger Lakes Atlas (FLI).. . Esatto (expensive - but complains) i am sure there is more good stuff out there... I am using moonlight 2" on my small triplet and FT 2" on the 2nd one. I was thinking to upgrade and open up to 3" electronic- Integra 85, or - just find out that ASA is still making their AAf3 My tele will be fast APO 100mm and on coming 10-14" barrel... i guess RASA doesn't need one? Please all experience welcome. Kindest Regards Greg

Hi guys, I have made a video of how to mount a Primalucelab Sesto Senso focus motor on a true 3" Feather Touch 3215 focuser. I thought some of you might wonder how to use the extra collar you need to mount the motor on to the bigger versions of the FT focusers, and also how to align the motor shaft. Enjoy

Hello, I recently purchased a sky-watcher focuser for my Celestron C8 (1997) sct together with a focal reducer. The focuser threads on the sct and so does the focal reducer. But how do I use both of them together. What I've found so far is, that one must first attach the focuser to the OTA and then the focal reducer to the focuser . But I can't see how I can attach the focal reducer to the focuser. What kind of adapter would I need? Thanks, AstroRookie

Hi, I recently made a video of how to mount a Sesto Senso focus motor to a Starlight feather touch focuser. I have now also made a video of how to calibrate it and also how to measure the backlash of the rack and pinion gear of the focuser. This method is not limited to a starlight feather touch focuser but could be performed on all kinds of focuser. I hope this video makes it easier for anyone out there having problems with backlash. You can also check out my other videos of the focuser / focus motor here: https://www.youtube.com/channel/UCm50WzpT1YKCwghW13b6k-g?view_as=subscriber

Hi all. I've been pondering over the idea of upgrading the standard focuser on my 200p to a dual speed one. This one: https://www.firstlightoptics.com/skywatcher-focusers/dual-speed-crayford-1252-inch-focuser-for-skywatcher-explorer.html This is primarily due to my frustration when observing the planets, especially when the seeing isn't great. I really need that extra tiny bit of precise focus, and the focuser I currently have just moves that notch too much when I try and fine tune. Do you guys think it's worth going for one of these? Also how easy is it to attach a new focuser? I don't want to go recking my scope by dropping screws onto the mirror 😅 Many thanks, Thomas

I have a Skywatcher 200p Dobsonian and wanted to use my 600D to get some better shots of the moon and planets than I can with my long lens. I have bought the T and SLR Ring which I have then plugged straight into the 1.25inch in place of the eyepiece. However, I can't focus on any objects in the sky, Jupiter and Saturn just looked like fuzzy doughnuts last night. Perfectly circular which is a start but still completely out of focus. This afternoon I thought I'd have another go in daylight and pointed at some trees approx 100-120ft away and the leaves were in focus with the focusser wound all the way in. With it all the way out I could focus on leaves on a shrub about 60ft away. I assume therefore that I need to get the camera closer to the tube but how? And how much? The tube that is screwed into the part that fits into the 2inch eyepiece holder is about 1.25 inches long but can I replace this? Does anyone have any ideas please? I can focus using normal eyepieces so don't want to resort to moving primary mirrors which was mentioned in another thread. As this is primarily being used for viewing not photography. Thanks very much for your help in this matter. Steve

Now I’ve managed to sort out control of my EQ6-R Pro using Stellarium via EQASCOM, I’m working my way through the other equipment I want to control from my Windows 7 laptop. I’m stuck trying to get my Celestron focuser to be recognised. This is what I’ve done so far: Downloaded the Celestron Focuser Utility Program (.exe file) from here: https://www.celestron.com/pages/manuals-software Also downloaded the December 2019 USB ASCOM driver set up from above. I ran the ASCOM driver set up and restarted the laptop. Connected focuser direct to laptop via USB. The focuser’s power light shows red and in Windows control panel it recognises the device as ‘Celestron Focuser’ but indicates no driver present. Ran the Celestron focuser utility program hoping it would connect and install the right driver so I could calibrate, but it can’t detect the focuser at all. Finally, ran APT to see if I could connect by choosing the ASCOM driver under ‘Gear’ but this doesn’t work either. Stuck now. I’m guessing I need to somehow ‘tell’ Windows where the driver is...? Any thoughts? Thanks everyone 🙂 EDIT: I have previously had this focuser working correctly both with StarSense handset and via ASCOM (Celestron unified driver) through the aux on my old Evolution mount. However, now I’ve changed to a Sky-Watcher mount, I need it to function direct through USB.

Especially to those among us that do unguided imaging a new and free software-tool I recently created may be of interest: FITSalize. When doing unguided imaging stability of the set-up is of the essence. Question is how one can properly assess the stability of a tripod or an observatory and distinguish flexure in the imaging train from deformation of the basis of the set-up. From the images themselves it is impossible to assess whether elongated stars are the result of tracking errors or due to stability issues. FITSalize is a command-line tool that runs under JAVA and uses ASTAP to plate-solve the images taken and to determine their SQM values. It is built to analyse FITS-files from a stationary scope (i.e. a scope firmly attached to the pier or base of the mount and pointing in a fixed direction) and to convert the images to accurate alt/azi coordinates. Being taken with a stationary scope the alt/azi coordinates should remain unaltered during the imaging period. Any deviation may indicate issues with the stability of the set-up. As these plate-solves result in J2000 RA/DEC coordinates they cannot be directly used to analyse stability. FITSalize corrects for precession to produce mean JNOW RA/DEC coordinates from the J2000 RA/DEC, then corrects for the effect of nutation in longitude and obliquity of the ecliptic and for the effect of annual aberration to find the apparent JNOW RA/DEC. These are then converted to alt/azi and stored (with all intermediate results) in a .csv-file. The algorithms in FITSalize are based on J. Meeus, Astronomical Algorithms, (Richmond (VA), 2005) and have been compared to results from the SOFA-library (many thanks to Massimiliano Chersich for testing this, he also initiated this type of measurements last year at the 10Micron forum) and with the algorithms in Han Kleijn's ASTAP and Stellarium (only Stellarium does not apply annual aberration to the calculations). Using your favourite spreadsheet (examples are provided) graphs can be produced to visualise the stability: Above example shows the stability of InFINNity Deck (my observatory) over a period of approximately six hours. Deformation in altitude was less than 4 arc-seconds, in azimuth less than 2 arc-seconds. In addition to deformation measurements FITSalize can also be used to plot SQM-values against alt/azi. For this regular FITS that were acquired to image a target are analysed: In this example light pollution affects the SQM-values in the north-east of the observatory. From those same FITS the focuser gradient and intercept can be calculated: For more info and download of the software see the FITSalize-page on my web-site. Nicolàs

Hello all! I want to upgrade the focuser on my Skywatcher 8" truss dobsonian. I want a dual focuser that's a direct fit to my Skywatcher. Any suggstions ?

Having suffered for some while with broken teeth on my Tracelscope 70s plastic focuser rack; I finally got around to doing something about it. First of all I cut a piece of aluminium (aluminum for our friends across the Pond 🇺🇸) the same size and dimensions as the plastic one on the focuser tube. Using the damaged one on the tube as a template, I marked out the replacement and began to file it down to size. Once this was done I copied across the positions of the valleys between the teeth onto the aluminium replacement. Using a manual mitre saw with a blade suitable for metal I cut the valleys. Some rough filing and the rack was almost complete. A hole was drilled at each end to receive a screw. I then cut off the plastic rack from the focuser tube, filed the cut flat and the glued and screwed the replacement into position. Due to the rough hand marking, cutting and filing it is not 100% smooth running, but at least it gives me full travel. A couple of pics: Broken plastic rack (removed). New aluminium rack glued & screwed in place

Hi All I thought I would share how I fixed my sloppy rack and pinion focuser on Skywatcher 130p. The issue? When using or collimating the slop in the focuser would put the target or centre dot way out of line. With the tube tilted downward I removed the 4 screws/nuts of the focuser to remove it from the OTA. Loosen the lock and 2 adjusting screws, I used a small torx screwdriver as i did't have an allen key small enough. Remove the 4 screws holding the adjuster bar in place, and remove the adjuster. Note: Be careful to avoid the very sticky grease used on the drive! Remove the draw tube assembly, remove the lock/adjusting shim located at the top of the main body. There were 2 plastic shims 1 each side of the drive I removed both of them. Thoroughly clean everything with degreaser and isopropyl alcohol except the drive itself. I cut 2 plastic shims from food packaging, cleaned them, and using 50mm double sided tape I lined out the main focuser body. Be careful to cut to the correct size and shape before installing and don't cover the drive or lock/adjusting shim areas. Next using teflon tape purchased from eBay I covered the draw tube exterior. I then did the same covering the plastic shims in the main body. It was still a little loose so I doubled the teflon tape at the top of the tube either side of the adjusting shim. Next I added a plastic shim onto the adjuster shim and covered with teflon tape. Put it all back together and almost no slack! I can now move the focuser from fully in to fully out without the collomation moving out of the centre ring on the primary. Complete success I think.

Do somebody using Dual-Speed SCT focuser for Cassegrain? Read about it and all of users say the same-it's a huge improvement. Can anyone share your experience with me in case? I found one on FLO - MoonLite CS Dual-Speed SCT Crayford ,looks impressive.

Hi, I have a 3" focuser on my APO 5" telescope. High quality and works very fine, except it could slip sometimes in the friction coupling. Even if I set the force higher with the adjust screw it slip sometimes. When the telescope get wet from moisture the water act as an oilfilm and lubricate the axis and steel plate friction surfaces. Now I must do something about this problem, took the focuser apart yesterday and looked after what was wrong with it. I have as usual documented what I do, for myselfe and all other that maybe have the same problem: http://www.astrofriend.eu/astronomy/projects/project-focus-friction/project-focus-friction.html I will update the page when I have done the first test after my fix. Any smart ideas how to increase the friction? /Lars

With my eye on an Equinox 120 ED, I am wondering if it's focuser can take an Astro Physics diagonal + ES 40mm Maxview total close to 2kg if not more - sort of challenge for any focuser bar imaging kit. The Featherlite is almost half the price of scope again!

Second sunny day in a row so another chance to play with my new Lunt 50 Ha scope. I had read Gary’s post so I knew there was plenty of limb activity on show. The large prom at the 2 o’clock position was fairly easy to spot but I struggled to find the others . I could see there was something there further down the limb but it was very indistinct. I played around with the pressure tuner but to no avail. It then occurred to me it was probably a focussing issue. I replaced the supplied focuser with a Feather Touch focuser. What a difference. Easily spotted the other proms and could make out a fair bit of detail. Although this is only a single action focuser it is very smooth to use and fine focus adjust is easy. Now after a warming coffee I will get back out and try to sketch the proms. Not that I am much good at sketching, but it is fun to try.

Hello all! I just installed this Lacerta 1:10 Micro Transmission focuser on my 8” Skywatcher Dobsonian. It is a direct replacement for the stock focuser and works extremely well. I was surprised at how easy it was to install! Ordered it from 365Astronomy and got fast shipping.