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Daf1983

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Posts posted by Daf1983

  1. 1 minute ago, KP82 said:

    The dew strips are designed to operate at 12V DC. If you plug them straight in the mains without any transformer, I believe they would just burn out (unless you make your own strips with appropriate wires I suppose). A dew controller can help control the power output so you don't overheat part of the tube causing air current.

    I'd go for a 12V 10A supply instead of 5A just to be sure there is enough power.

    Hi,

    Sorry, what I meant was, straight into the mains via the adapter https://www.amazon.co.uk/Cigarette-Lighter-Adapter-110V-240V-Converter/dp/B07BHNGFGV

    So for 12V 10A, I would need a different controller and adapter?

  2. Hello, and sorry for yet another question. I have a Skywatcher 80Ed on order, and am looing into Dew Prevention measures before it arrives. I will be powering everything from the mains, so I'm a bit confused as to how you power the Dew Strips, which all have cigarette lighter types socket. The only solution I've found is as following:

    Dew strips into Dew controller probably this one from FLO https://www.firstlightoptics.com/dew-prevention/hitecastro-single-channel-dual-port-dew-controller.html

    The plug in the Dew controller cigarette lighter into the mains via this https://www.amazon.co.uk/Cigarette-Lighter-Adapter-110V-240V-Converter/dp/B07BHNGFGV

    I'm assuming this setup would work, but are there any easier alternatives to the above?

    Could I plug the strips straight into the mains and run it on full power, or is the controller a necessity?

     

    Thanks

    Dafydd

  3. 5 minutes ago, KP82 said:

    That 10mm refers to the thickness of a standard T ring. In the case of Canon, the flange distance is 44mm, so with a 10mm thick T ring you will already be at 55mm (ie no extra extension required).

    The 55mm quoted in the product description is most likely for the slower end of the working range. Since your 80ED is f/7.5 which is so close to that f/8 limit, my guess is that you will probably only need 1-2mm extension. Just to be safe I'd suggest a 3mm extension tube + a couple of 1mm and 0.5mm spacer rings. Make sure you get T2/M42x0.75mm extensions rather than M48 because the Lightwave 0.8x has a T thread at the camera end.

    https://www.ebay.co.uk/itm/High-Quality-T-T2-M42X0-75mm-Extension-Tube-3mm-5mm-6mm-10mm-and-20mm-NEW/371113516507?hash=item566816dddb:g:ovEAAOSwDk5T231-

    https://www.harrisontelescopes.co.uk/cgi-bin/bb000001.pl?ACTINIC_REFERRER=https://www.harrisontelescopes.co.uk/cgi-bin/bb000001.pl&PRODUCTPAGE=baader-t-2-adjustment-spacer-ring-set.html#SID=1664

     

     

    Brilliant, I think I've got it now! Thank you👍

  4. 1 hour ago, KP82 said:

    You could always email Nick at Altair to find out if he knows. Considering the high popularity of the 80ED and the compatibility with the Evostars are specifically mentioned in the product description, maybe people at Altair have already got the answers for you.

    You could also start the trial & error from 55mm on your own. Being f/7.5 (so close to the upper end of the working range) I believe you won't be too far off with the 80ED.

    It says on the altair website that you need approx 10mm space for a dslr. Does the this mean that the reducer itself provides about 45mm(sorry if this is a stupid question)? 

     

    If so, is it something like this I need?

    Thanks again

    Screenshot_20210131-182019.png

    Screenshot_20210131-190828.png

  5. 3 minutes ago, KP82 said:

    Assuming this is the one you plan to get:

    https://www.altairastro.com/lightwave-08x-reducer-290-p.asp

    It's a generic reducer for refractors between f/5.5 and f/8, so it will work on the 80ED. But unlike a dedicated unit for which the manufacturer tells you the optimal spacing (usually 55mm) between the reducer and the camera, you will have to work this out yourself for a generic one like the Altair. The rule of thumb is that the spacing is usually shorter (usually about 55mm) near the slower end of the reducer working range (f/8) and longer towards the faster end (f/5.5).

    Great, that makes much more sense now. Hopefully someone who has used the same combo can give their insight, so that I have an idea of the optimal spacing.

    • Like 1
  6. I'm about to order the evostar 80ed, and have decided to pair it with the altair x0.8 reducer.

    I already own a unmodified Canon 600d along with a t ring. 

    This will be my first ap rig, and I'm a bit lost with what I will need to connect everything together and be able to reach focus.

    Will I need any other adapters/spacer etc, or will the above be enough to connect everything and reach focus?

  7. 14 minutes ago, Stub Mandrel said:

    Bear in mind the ED72 will need a flattener as well so if used with the SW flattener the relative lengths remain the same.

    I have no trouble imaging small, faint DSOs at F8, personally I don't find that aperture makes as huge a difference as I would expect, but it's affected a lot by other aspects of your setup too.

     

    <edit> I should make it clear the primary reason for a 'reducer' is its role as a field flattener and improving star shapes - changes in focal length are a 'side effect'.

     

    I was initially thinking of pairing the 72ED with an OVL flattener (which doesn't alter the focal length), but after the advice I've received on here, I'm swaying heavily towards the 80ED. I think I will use it without a flattener/reducer to begin with, and keep an eye out for a second hand reducer while I save some pennies. It's good to know that some imaging can be done at it's native speed of f7.5. 

    I'm not expecting to get amazing results to begin with, so am happy to take the time to get used to the mount, while I save for some guiding equipment and a reducer.

    Thanks again for your advice

  8. 49 minutes ago, KP82 said:

    You will need a dew heater and stripes for these cold winter nights.

    Also I'd recommend guiding which would greatly improve your imaging experience and reduce the amount of wasted subs. The software is readily available and free. Personally I was using guiding from day 1. The only thing that would have stopped me was my budget.

    A mini-PC or RPi or an old laptop which you don't mind leaving outside in the cold would be handy if you're going to image from your backyard. You could wire everything to it and then control the whole rig remotely from another computer in the warmth of your house.

    Hi, this is definitely the plan eventually, however I only have one laptop, and I use it with work, so I'm reluctant to take it outside. When budget allows, I will get a cheapish 2nd hand laptop which I can take outside.

  9. 1 minute ago, 7170 said:

    Can I suggest you consider looking into a 12v 10amp CCTV power adaptor instead. About £15 from a well known online retailer and I have found them to very reliable long term. 2.1mm splitter leads are cheap too and 10amp gives you ample current for future equipment, or DIY/purchased dew bands etc.

    You will probably also need some T2 extension tubes (again cheap online) as you don't want to use the diagonal, and with my ED80 the focus tube is out further than I like with no extension tubes and a camera on the end. I don't use a focal reducer though.

    Thanks for that. The power supply is something that's been bugging me. The lynx power cable seems very expensive for what it is, but coming from a position of zero experience it's difficult to know what alternatives will work

  10. 3 minutes ago, fifeskies said:

    You can select plenty bright targets to get used to the whole process, where the slower scope wont be such a problem.

     

    Orion Nebula , Pleiades , M31 Andromeda , North America Nebula , all should be good starter targets., as well as some globular clusters , and don't forget some Lunar imaging as well.

    Also recommend the free APT software and DSS to stack lots of shorter exposures and so get long "integrated" times.

    Free and there are plenty good tutorials on using them , also free GIMP for stretching the final results to bring out the DSO targets.

     

    I did start with the advantage of the Faster Equinox version of the ED80 and bought it 2nd hand with the 0.8 TV reducer/flattener in the pack , so it was a lucky find for my first imaging scope.

    It's good to now that it's useable without a reducer. I'm being swayed towards getting the 80ed without a reducer to begin with, and keep an eye out for one on the 2nd hand market.

    I've used dss and gimp quite a bit while imaging with dslr and lens, so at least that's one less thing I have to learn!

  11. 5 minutes ago, fifeskies said:

    The TV one suits any scope of 400-600 according to the box , but I had seen it recommended may times for the ED80.

    It is 0.8 so gives a big advantage reducing the ED80 to 400mm (from its 500mm native) and speeds it up to F5.

    Just see what other's think of any reducer you consider.

     

    Don't worry about a reducer at first , you may get some edge coma but when starting out there is a lot to learn before worrying about all the bells and whistles. You can get some nice images (and can crop if you think the edge is bad).

     

    Another ED80 pic below , North America Nebula , also from my unguided days and only 90 sec exposure time.

    Its nice and bright so you don't need as long as with the fainter targets

     

    trf_box.JPG

    North America Nebula 5 nov 2020_TUT-vert_40_micro.jpg

    Thanks again for the input! My only worry with using the 80ed without a focal reducer, is that it would be too slow, especially as I won't be guiding to begin with. 

  12. 1 minute ago, Gerr said:

    I was lucky and bought my ED80 second hand from this forum and it came with a SW Field Flattener.

    My ED80 'speeds' up to f/ 6.37 with this!!

    Unfortunately these are expensive new (just like most things in this hobby).

    However;

    I connect all my stuff through EQMOD / ASCOM / EQDIR cable to Astro Photography Tool (APT). This software is brilliant  and you can control your whole imaging session with it. It works seamlessly with guiding camera (PHD2), HEQ5 mount control, camera functions and sky charts (Cartes du Ciel - is best). It basically converts your telescope and mount into a stand alone and remotely controlled set-up. APT is free (you do have option to pay 18 euros for full fancy version) and so are all the other applications.

    You do need a laptop and connecting cables (especially EQDir to mount).

    I have not looked back since.

    Gerr.

     

     

    This is my plan eventually, but I'm trying to take things one step at a time.

  13. Just now, fifeskies said:

    I bought my Televue reducer flattener second hand (TRF-2008) , they come up fairly often and was a fair bit less than the dedicated one new.

    Thanks for that, I've seen a few people use the altair ff/fr also. Am I right on assuming that any field flattener will work as long as it matches the specs of the scope?

    • Like 1
  14. 1 minute ago, Gerr said:

    Hi Dafydd,

    I am up the Donkey in Holyhead and use a HEQ5 Pro and have an ED80 Refractor.

    Your set-up is similar to mine and it is a great combo for wide field targets such as the North America Nebula and also big galaxies like Andromeda.

    Bright targets like M42 you can achieve unguided but most of my imaging is in the order of minutes (usually 3 or 4) to achieve good results.

    Consider a SW EvoGuide 50ED Refractor scope and ZWO AS1120mm Mini guide camera combo (see FLO site) as a solution for guiding long exposure astrophotography.  

    I do find I can get dew forming on the lens of the scope (even though I store equipment in a cold garage before use). I have made cardboard dew shields as a cheap solution to this.

    I also use light pollution filters to reduce light gradients in my images and a field flattener to eliminate lens field distortion.

    Gerr.

    Thanks, that good to know! Looks like I'll have to invest in some guiding equipment sooner rather than later!

    What field flattener due you use with the 80ed? The main thing that's putting me off is the skywatcher ff/fr is about £180, which makes it a much more expensive option than the 72ed (where you can use the ovl flattener)

  15. 14 minutes ago, Stub Mandrel said:

    ED72 is a much shorter focal length, making the ED80 more of an all-rounder. I suggest using the field of view simulators in Stellarium to look at how they suit different targets.

    Bear in mind though that if you go for a dedicated astro camera in future it will probably have a smaller sensor, especially if you want to stick with 1.25" filters

    I have a scope made with the lens from the obsolete ED66 that is superb as a wide field scope and is same focal length as the ED72 (400mm) there are some hints the ED72 may not be quite as sharp being a faster scope than ED80/ED66, but personally I doubt it's noticeable under most circumstances. The ED66 complements my 130PDS which is similar Fl to the ED80 with the coma corrector (590 vs 600mm).

    I also have a 1200mm scope for small DSOs and planets, and various wider camera lenses.

    Of all of them I think ~600mm (130p-DS/ED80) is a 'sweet spot' in terms of price/performance and flexibility of targets, but that's only my view.

    A good combo might be ED72 and a 130P-DS for not a huge amount more than an 80ED alone.

     

    Would the 80ed not need a focal reducer to make it quick enough for imaging? This would bring the focal length to 510mm (with 0.85 reducer which most use), which is not that much longer than the 72ed. I'm not disagreeing with you by the way, just trying to get my head around both optiins😁

    I've had a play on the field of view simulators, and while the 80ed is probably better for more targets, I felt there wasn't much in it(assuming you use a focal reducer)

  16. 25 minutes ago, Stub Mandrel said:

    I think taking a step at a time is sensible, I feel that in many ways it makes the journey more rewarding.

    But I would go straight to a scope that will serve your needs long term. The ED80 should tack for a minute or longer if you have good PA and the mount is well adjusted.

    The step to guiding is relatively cheap if you already have a suitable laptop, so you pr4obably won't take too long before moving forwards.

    I have to be honest, this has been my major dilemma! Would the 80ed give much better results?

  17. Short subs - I'm assuming as I won't be guiding to begin with, I won't be able to obtain very long subs. But I take your point on needing to guide to get good results, but I want to get used to using a eq mount and polar aligning etc first, before I add an extra layer of complexity which guiding brings (plus I've blown my budget on the mount and telescope😪)

    As you say, the best thing to do is try and see what works. 

    Thanks for your input

  18. Hi, thanks for the reply. I live in bortle 4 skies, so I'll see how I get on before investing in a LP filter. Also, as I won't be guiding to begin with, am I right in saying subs won't be long enough for LP to be an issue?

    I have a laptop. With regards to dew control, I 've had no issues at all with due while imaging with a dslr and lens,. Would a refractor be any more prone to dew than a standard lens?

  19. Hi,

    Having done a fair bit of observing with my dob and imaging with DSLR, lens and the Omegon Minitrack over the past year, I'm ready to invest some money in a more serious astrophotography rig. I've read 'Making every photon count' (twice), and I think I have an idea of what I need to get started. My logic is to start with a fairly simple setup with no guiding, and then build from there. This is what I have in mind:

    1. HEQ5 pro

    2. Evostar 72ED - I decided on this rather than the 80ED to make it easier to track unguided 

    3. OVL field flattener

    4. Astro essential dovetail bar - in order to balance the scope properly

    5. Lynx Astro 12v DC power supply - to power mount from mains supply

    6. DSLR and t ring adapter (which I already have).

    Befoe I pull the trigger, is this a decent starting setup to get into astrophotography, and does anyone have a similar setup? Have I missed anything that I need?

     

    Thanks in advance

    Dafydd

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