How to Set Up The ZWO EAF

In this video, we go over how to set up the ZWO EAF (Electronic Auto Focuser). Focusing is easy but some things can cause you to lose focus throughout the night. Adding in the Autofocuser keeps your stars sharp!
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[@wdavis6814]

I didn't mind focusing until I started doing narrowband, and after a few botched narrow band stacks, I got the EAF. Can't wait to use it.

[@Noncenx]

This was really helpful. While not exactly like my Apertura 75Q, it as close enough that it made attaching the EAF super easy. Thanks for taking the time make and post the video.

[@bridgeforth]

Thanks for the video, it helped me set up my ZWO EAF. An update on manual control, QHY now has their own EAF and they built in a knob that allows you to control the unit manually if you want. The price is really well placed too for that EAF. For those not dependent on the ASIair ecosystem it is definitely worth looking into.

[@AstroEscape]

That is awesome, thank you for sharing that bit about the QHY EAF.

[@robb7342]

I've decided to pull the trigger and get the EAF, so the entire video was of great value as your approach is always straight forward and easy to follow. Thanks!

[@AstroEscape]

Awesome! In the months since this comment, how has it been for you? What have you imaged?

[@robb7342]

@@AstroEscapeOverall problem free, the EAF just works. With limited clear skies I've still managed to get out to shoot several DSO's like LDN1266, Tadpole, Rosette, Iris etc.

[@karlfortner887]

RASA HD8, EAF and ASIAIR+; are two of the best options I've purchased. Makes setup, focus, polar alignment and finding the target super easy.

[@AstroEscape]

Very nice! One day a RASA will be added to my inventory..... The AIR is makes it super simple.

[@mikehardy8247]

You asked if viewers were going to get the ZWO EAF? I didn't think $200+ was necessary, but... During NEAF, ZWO, and HIGHPOINT, had the 20% sale. I bought one, and external temp sensor. Finally figured out how to mount it, thanks to this video! A little confusing getting it to work. Was like. My question to you when I first got my ZWO 533MC Pro. How to get close enough for EAF to not be lost. ASTROWORKZ answered that. Go out at twilight, turn gain low, and exposure time fast, and tap manual buttons, or if you bought the hand controller, adjust with that printing at a distant object to get focus as good as possible. A day later, and I couldn't be happier. Imaged M101+SN last night for about an hour. Tonight I got 3 hours in. Temperature dropped, an holy crap! It stopped the imaging, and adjusted focus several times! Glad I got it. Now when I have everything broken down, I've got good reference numbers if it moves, and can be confident that critical focus is achievable.

[@AstroEscape]

Well, it isn't _necessary_ , but it is worth it! It's a game changer for sure in making sure everything stays sharp!

[@mikehardy8247]

@@AstroEscape Face it, we love our toy's ! I'm thinking of trying it with Rokinon 135, where it might be WAY more useful. I find that lens less than easy to focus.

[@meibergstrmandersen9181]

This was really helpful, thank you ! I just installed the ZWO EAF on my Altair Wave 115 EDT-X scope. First time astronomer 🙂

[@AstroEscape]

Awesome! I hope you got some great images since then!

[@CeresIsAwesome]

THANK YOU! I could not for the life of me figure out the guide for how to remove that thermometer knob. Stand-still pictures do not explain enough ... you have to ROTATE the knob with the wrench in to find the screw inserts. Man, I thought I was just insane. This works on the new RedCat 61 as well, so this is much appreciated.

[@AstroEscape]

Awesome man, glad it helped!

[@jonrobinson1026]

Great help,thanks. Does it work without the ASI? Eg..in NINA. Can't afford both EAF and ASI 😢

[@Mainuh]

Waiting for me EAF to arrive and put on my new ZWO FF65. Very helpful video! Thank you!

[@AstroEscape]

Hope you have gotten it by now and given it a run! It does change the game for sure 😀

[@danielburdick8213]

As always wonderful video! I feel like I learn something new each and every time you post something! Keep up the good work!

[@AstroEscape]

Thank you Dan!

[@robertgrenader858]

In setting up the EAF on my RedCat51, I had to do a manual focus before installing the EAF and make sure the EAF is in the roughly center position. This prevents a lot of lock-to-lock flopping around as the algorithm finds focus the first time. The benefit is, you don't drift out of focus each time the scope is set up, which makes refocusing a lot easier.

[@robertgrenader858]

@tradde11 For a RedCat 52 or 71, get the Black Cat device from ProAstro Gear (Agena Astro) to mount the EAF, ASI AIR, and your guide scope. I' post a link, but I thank that is forbidden on KZbin?

[@AstroEscape]

Nice tip, Robert! Good to know for those using a scope with that style focuser.

[@juliand2107]

mine does an autocalibration first, to find the endpoints to prevent that.

[@robertgrenader858]

@@juliand2107 So does the EAF on my RedCat, but only after a manual focus (the only time I"ve used the integral Bathinov mask). This prevents excessive faffing about when the EAF attempts to focus in a production mode. Right now, it takes about 2 minutes to achieve autofocus.

[@dadwhitsett]

Well, after 8 months of imaging with my Esprit 120 mm I decided to get the EAF. I have been surpised how much the temperature changes affect the focus. Haven't had a chance to image with the EAF yet but am hopeful. I appreciate the video muchly!

[@AstroEscape]

Thanks for watching! Yes, it can really mess with things if there's a big temperature swing. Have you used it since?

[@Si-fp2ij]

Great point about the manual focus, setup a new scope only to realise i was miles off of focus to begin and had to take it off again.

[@AstroEscape]

Yeah I really wish that, well, all manufacturers would include a way for manual focus.

[@Vventimiglia1984]

Great Video! Do you think these steps would also apply to the new Redcat 71 WIFD?

[@robertsipes7391]

Just ordered the new EAF from AgenaAstro. I've been putting it off, but this video pushed me over the top. I hope I'm not diappointed. I think I WILL like the autofocus feature.

[@AstroEscape]

It's been great since I started using it. I'm glad my fumbling in this video could help you haha!

[@Chorge1972]

Superb!!! Thanks so much

[@uvb7675]

Thanks for Video. Is it not necessary to determine the backlash before?

[@AstroEscape]

It's probably a good idea..... but I haven't had any problems so far skipping that.

[@astrodad656]

Regarding the inability to manually focus...I am sure to write down in my notebook for each scope rig the focus location [when markings are availabl,le]. If no markers I will precisly measure [such as on my SCTs]. It takes a loooong time to find focus with the EAF when it is way out of focus!

[@AstroEscape]

Awesome tip, thanks for that man!

[@thejaguarGamer]

Great video! I didn't see anything about calibrating the focuser for maximum in/out. I bought and EAF and will be installing it on a EdgeHD8. I currently have a Celestron Electronic focuser and it had a calibration routine which ran the first time. I tried using the Celestron focuser first but every time I try to focus it disconnects the ASIair from my AVX. So I bought a EAF to see if that will be better. But I am looking for information on calibration. Thanks!

[@amp2amp800]

Another great vid, thanks! Yeah. I never wanted one on my "all-rounder" rig because of that last point you made. No clutch, no hand focus option, no good. End of story. Also my definition for an all-rounder rig is that it needs to be able to do everything, and needs to stay usable no matter what happens. I designed my 130 APO on EQ6 rig to be able to deliver a push to visual experience if all else fails. I have a crosswire finder in the eyepiece bag and a hundred objects in my biological target database. I usually use it for deepsky or moon/planet photography, but I love eyeballing too. It has triple fallback (asiair, synscan, push-to) so fun is guaranteed if skies are clear. An EAF without a clutch compromises that concept. You always need power, cables, EAF & ASIair or it's a wash out. All that being said, I *did* buy an EAF for the widefield grab and go that I'm currently building. There I made specialization choices that incidentally lock me into using an ASIair anyway, so in that case why not EAF too?

[@AstroEscape]

A clutch is one thing I REALLY hope they add to a future version. That's a good design with your all-rounder! On your last point there..... yeah, you have a point there!

[@larrycable984]

@@AstroEscape @amp2amp800 why not use the optional hand controller?

[@amp2amp800]

@@larrycable984 Yes, I'm planning to check out the EAF on the big APO with HC for planet/moon photography and visual (and I already bought the HC with these use cases in mind). But its an Orion 130ED and *NOT* in the list of supported equipment. It looks as if it will be easy to make it fit... but I already had trouble with simple four-screw mounting of a losmandy dovetail to the Orion tube rings, and it *seemed* to me like Orion use non-metric threads. So I'm anticipating some downtime while I source small items or find a way round similar obstacles. I don't want to be swapping back and forth so IF the EAF transfers successfully from the grab and go, it will stay put. I'll buy a new one for the FF80 as soon as I'm confortable about committing to the purchase. Now its just a case of watching out for a good moment (with some evening planets).

[@andrewsalotti7257]

I have the same scope. But, after fitting the EAF I found that it interfered with my HEQ5 mount. The solution was to rotate my scope so it is now 'upside down' on my mount, the focuser is on top. Cheers

[@AstroEscape]

I haven't put it back on the HEQ-5 since I got the AM5... I'll have to do that. How did it interfere?

[@andrewsalotti7257]

@@AstroEscape from memory I think the L bracket for the EAF didn't clear the mount base.

[@peeb2896]

@@andrewsalotti7257 Same here...I have the EQ6 and same thing, focuser housing buts against the dovetail securing rail knobs and you Andrew....have answered my question!

[@andrewsalotti7257]

@@peeb2896 cheers mate I'm glad I could help out.

[@2badger2]

Good video! I have a Williams Optics 120mm (780mm focal length) and have been thinking about this auto focuser. Did you add any counter weight on the other side to offset the weight of the focuser? Better balancing? Thanks

[@AstroEscape]

Nope! Works fine without adding any extra weight :)

[@jonathanritter7364]

Do you roughly polar align...then auto focus before polar aligning? Get focus...then true polar align....then move to your target? And also now that focus knobs are being messed with..after roughly polar aligning...if focus is out..and you cant adjust it due to the knobs being locked up from the EAF...will the EAF still find focus even if you are NO WHERE CLOSE at set up?

[@mariospenard5125]

Useful information. Thank you!

[@AstroEscape]

You're welcome Mario!

[@BriggsBrian-on9nb]

What guide scope and camera are you using?

[@michaelclancy7874]

I had my ZWO EAF on my Redcat. Moved it to a new scope, Skywatcher Esprit 100 ED. And I have the same issue about adjusting focus to start. Would be great to disengage the EAF somehow. Wonderful tutorial. Thanks, Mike

[@AstroEscape]

An unlock would be the best next addition to all brands that put out an EAF.

[@1clancym]

@@AstroEscape one with around is to buy the ZWO remote for the eaf. No clutch but you can easily run the focuser

[@dannyfurdon]

@@1clancym SO i do have the remote and I'm going to be installing on a Celestron EDGE 8 I haven't had any chances to focus it on much deep star objects manually and fairly new to this. my question is can i go ahead and install the EAF then use the remote to get into focus then concentrate on the settings for the EAF? Thanks in advance

[@refetastro]

Excellent video Question I used apo z81 and focusing actin like flip flap mirror on sct when I use fine focusing by hand no auto focus Do you think was damaged when they has auto focuser ?

[@AstroEscape]

Did you put the focuser on yourself? My other question is, do you have problems when it is focusing with the EAF or just manually?

[@refetastro]

@@AstroEscape No i didn’t ad any focuser im assuming the ine who had the scope before me maybe they did it . The flip flop I get it as I use manually focusing by hand Thanks

[@3_Gold_Coins]

I just installed this on a WO Gt81 wifd. I pre set my focuser to the mid range. I also have the hand controller.

[@AstroEscape]

Nice! It'll be a game changer for you for sure. Now you can focus first thing!

[@3_Gold_Coins]

I was able to focus during the day on a distant mountain peak. I need to focus the guide scope. I’m not sure how to do this with the asiair. Any suggestions?

[@mickymaggots]

Hi, you never mentioned adjusting for backlash, quite essential. Mine is fitted to William Optics Zenithstar 73.

[@AstroEscape]

Good catch, I didn't think of that when putting it together. I'll keep that in mind for a future video on the EAF.

[@videoscrapheap]

Try unplugging the EAF and see if you can manually focus. Servo motors require power to hold position so unplugging it will remove power and allow the motor to turn.

[@AstroEscape]

I will definitely give that a shot and let you know!

[@gptravel531]

Thanks! .. Thanks! .. Thanks! Followed along and installed mine tonight on my Z-61. You wanna swap your red for my blue? Please! 😁

[@AstroEscape]

Hahahaha I'm sorry but I'm partial to the red, it goes well with the ASI AIR :P Glad it helped.

[@jurgen77emmen]

Excellent video!

[@AstroEscape]

Thank you very much!

[@VikramHarinath]

When using Focus mode in the ASIAIR App to run the Autofocus routine - do you need to have tracking turned on for the mount? Should you do a PA routine first to allow for the ASIAIR to track and platesolve properly?

[@AstroEscape]

There are a couple of ways to do that. If you know where focus generally is on your scope (such as a refractor), you can manually set the focus to near there so the air can make out the stars for PA. Or, once you have it focused, store it that way if at all possible. I would say yes, have it tracking so it can accurately focus. So, manually get close to focus -> PA -> focus -> PA again (optional) -> go to object.

[@AllanDer]

I just got the ZWO EAF and I noticed that the ASIAIR+ automatically turns ON tracking on the EAF. I was trying to focus on an LED light at a distance and it kept drifting away. I was able to turn off tracking with the mount hand controller as soon as the tracking came on.

[@TelfordO]

Planning getting one.

[@AstroEscape]

It's a game changer! Swing back by when you get one and let me know how your first image turned out, please. :D

[@perry3928]

I'm getting one for my 8se. I want to fully automate so not to freeze in the winter or get eaten up in the summer.

[@AstroEscape]

Good call! It should work out pretty well for you!

[@MrTyroneweaver]

I had to do a little fabrication to put it on an ST80

[@bronco_fv]

Bought one straight away along with my Esprit 100ED.

[@AstroEscape]

That's the 'Esprit'! Sorry for the bad joke. That combo will be awesome for you.

[@bronco_fv]

@@AstroEscape well it is indeed. I’m less enthousiastic about this EAF on my EdgeHD 925. I feel something like an Esatto fron Primalucelab would work better.

[@incubus442]

Can you mount a guide scope to the bracket for he EAF? I have a SvBony SV106 guide scope and I am wondering if the EAF will get in the way of it?

[@AstroEscape]

If you mount the telescope upside down so the bracket is on top.... maybe. You'd still need a dovetail base to put it in, and at that point you could just put it where the visual finder scope goes.

[@markhehir7253]

@Astro Escape I have tried that. The problem is that my guide scope gets in the way of the focus wheel. So, earlier today, I ordered a new riser and a new vixen dovetail, which is longer than the one that came with my scope.

[@mikehardy8247]

I'm in a "catch 22", kind of loop. Until now I've been using a DSLR. Focus is real time in live mode. Now with ZWO 533, asiair, and an OTA, everything is delayed on Tablet screen. Making manual focus a royal pain, at least for me. To plate solve you need focus. To find a star to do focus, that star has to be in focus. I tried in semi cloudy skies to aim on the moon, to achieve focus. It's so touchy, with gain, exposure time etc. I never got moon in focus before clouds overwhelmed the sky. I'm dizzy! Next day i got a lam post a half block away in focus. Will EAF at this point confuse more, or help? I'm juggling all new stuff. Maybe too much at once. DSLR, lens, tracker before. Now asiair, ZWO camera, SA GTI, so tracker, guidescope. Virtually no clear nights, bitter cold and snow. I know this "right of passage" is nothing new to most everyone. I guess my rant is all to ask if the EAF will help or hinder? Your a great teacher! How I got through asiair setup.

[@AstroEscape]

For the 533 it'll help. You didn't mention the specific scope you use. But, what you could do is attach the DSLR, get that focused with live view, and take note of where it is in focus on the scope. It'll be slightly different for the 533, but close to the same point. Make sure you have the correct spacers on the 533 as well. From there, when you set up you can get it to that point where it's close to focus and you should be able to make out stars, even if they are blobs, to get polar aligned. With the EAF attached, you can have it sit on your pole and focus for PA, then redo focus on something further from the pole afterwards.

[@mikehardy8247]

@@AstroEscape Wow, I didn't think DSLR and 533 would be similar enough backspacing to work. OTA is Apertura 60mm FPL-53 Doublet Refractor and 2" Field Flattener. Modest Doublet. Light enough to not stress 11 pound payload of SA GTI. HIGHPOINT Signature brand. There's a site "HYPERSPACE" run by Jack Napier, where the creator basically tells you everything about setup of all I have. I bought first, and found site after. Spacing is correct for 533. Like I said, I've got it close. Next chance, I'll try again. Thanks for speedy response!

[@mikehardy8247]

@@AstroEscape Should I put DSLR directly on FF, removing 533 and spacers first, I assume?

[@Fred-ox3gq]

Make sure your back focus is correct, or focus might be outside of your focuser's range. Add extension tubes until focus is roughly in the middle of the range. You can do this with a distant object during the day from the comfort of inside, through a window. Also make sure you have a good USB cable. The USB 3.0 cable that came with my ZWO camera gave me frequent errors that showed up in Asiair as "overexposed". I replaced it with an Amazon basics one and had no problems since.

[@mikehardy8247]

@@Fred-ox3gq I've been fortunate enough, over the past week or so to have a few nights nature cooperated! I achieved a rough mechanical polar alignment (with phone compas and digital protractor). My light pole focus was too fuzzy for plate solve, but good enough to refine star focus to point that PA was successful! Found a bright star, achieved pinpoint focus with Batinov mask! I'm off to the races. Was confused when mount rotated on polar axis about 30 degrees, and told me PA was successful. I was of a mindset that scope had to be inline with mounts polar scope. Perpendicular to ground. This revelation is "freeing". Successfully imaged whirlpool galaxy Saturday night. I actually brought scope out, setup and had imaging plan going in under half hour. Monumental breakthrough. THANK YOU everyone. Now to get autoguiider focused, and implemented in workflow.

[@MrMa1981]

Where goes all the check captures raw files to reach the focus during the session?

[@AstroEscape]

I'm sorry, can you please clarify what you mean?

[@MrMa1981]

@@AstroEscape Mmm what the EAF and softwares actually do during the night?

[@cdh79]

I have an EAF on my spacecat (with a 3D-printed adapter and a belt) and I also have a Primalucelab Sesto Senso automatic focuser on my Takahashi FSQ on which I replaced the stock focuser with a feather touch. Also, I think your focuser step is too small with 30.. you're having a U-curve instead of a V-curve, so the difference in FWHM (or whatever it uses to calculate) doesn't change too much between the different takes.. I suggest playing with the values, so you'll actually get a V-curve.

[@AstroEscape]

Thanks for the feedback. I'll change the steps next time it's clear :)

[@alangriffiths1432]

Mine is on Red cat51, and it's work great

[@AstroEscape]

Nice! Bet your pictures are nice and sharp!

[@heraldofsolace]

I stripped one of the grub screws and couldn't take it off lol

[@AstroEscape]

Oof, did you figure it out?

[@bonnietiedt1721]

Mounting on a WO gt81

[@AstroEscape]

Can't go wrong with that! How has it been?

[@WillisReardon-q3q]

Leanne Shore

[@ChelseyCrupe-c9b]

Anderson Common

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Jevon Crossroad

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Schaefer Brook

[@avaliseoldman282]

Zachary Avenue

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Lillian Estate

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Pearline Lakes

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Skye Islands

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Hagenes Dale

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Roberts Centers

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Dietrich Cliff

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Bins Brook

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Carmelo Walk

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Era Port

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Schulist Run

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Wunsch Village

[@MimiKnight-n7u]

Celestine Union

[@fernandoneirapaz]

Why dont you read first de instructions manual man. You dont need to figure out everything you know 😂

[@AstroEscape]

Ahhhh where's the fun in that? Then you can't watch me screw up in the process :P

[@anata5127]

Just don’t. Backlash of that “focuser” will vary from day to day, from target to target. That focuser is Okish for EAA, but not astrophotography.

[@AstroEscape]

Haven't had a problem yet, but it is still fairly new. We'll see how it is after a few years :)

[@anata5127]

@@AstroEscape How do you know that you have no problem. Maybe you do, it is just not noticeable. What are FWHM and eccentricity of your frames? I had very average numbers. I blamed small scope for these numbers. Then, I realized that ZWO focuser doesn’t return into the same spot, and backlash is unique every day. One day 90 steps, another 110 steps. You will not even suspect this if your scope is small and targets are massive.

[@SamanthaMatthews-b8p]

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