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About Howie_Oz

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  1. new mask for you to try .... https://www.youtube.com/watch?v=IeUs7pFwMJw
  2. Thanks Martin, wonderful find! Also thanks for adding all the coords etc to your image. ;)
  3. Unfortunately my desire to get out and use it / test it out has been stuffed by the almost total cloud tonight. As soon as it clears I'll give it a try.
  4. Yes, I've downloaded it on Windows 64 bit and due bad weather just played with it during daytime and last night around 11pm pointing out the window down the street (due 100% cloud cover). Tonight is forecast to be clear'ish with around 30-60% cloud between 6pm and 9pm and socked in after that. Hopefully I can use the ASILive component to do live stacks of short exposure and see for myself. CN forum has a thread where several folk have tried the same component (ASILive) and found the controls very simple yet the final stacked result very similar to SharpCap's stacked result. They posted images comparing both. I've also watched a few live NSN "astro at-the-scope-using-it broadcasts" and it looks very simple to operate. So it bodes well ... but the proofs in the pudding, so hopefully will try it out tonight. Will post up my results. I love HD desktop video captures so will try to get a few to post links to. A PRO feature is that it is has versions for Linux Ubuntu, Mac OSX and Windoze (32 and 64 bit versions). It's the Mac part which is interesting for me! All my astro so far I've done on a bootcamped Macbook Pro - due to the software I've needed being Windows only. I hope today to download the Mac version in readiness for tonight. The big issue for many will be it only works with ZWO cameras, ZWO e focusers, ZWO e filter wheels, ZWO guiders. Anyhoo, hopefully will test tonight. [edit] .... BTW I downloaded it from the official ZWO website under their Support ---- Software webpage. ZWO website is astronomy-imaging-camera.com Cheers
  5. Have fun ... you already own the Canon so give it a shot. If you hate it, or struggle with it, then like I said ... the ASI224 has been for a long time the go-to starter cam for the high sensitivity needed for very short exposure Alt Az EEVA. Many forums could propose other cameras ... up to you to wade through all the suggestions and advice re those options. There are some new cams which people love. I'm biased because of personal experience and maybe how I adjust the SharpCap software .... I try other club members cams, and friends with other cams, and for me ... I keep coming back to the 224 or 183 (or even 185 but its very close to the 224 FOV and with more read noise than the 224). BTW you've experience the learning curve with StarTools ... so you know finding info on a workflow which makes sense to you, and which when you try it with your images .... takes a bit of effort! When you try out your DSLR with, or without AT (thats AstroToaster), you are going to have that same steep learning curve with AT software. It will take effort and in the end the use may not suit the way you think. Ditto buying a true EEVA modern cam like the 224 using SC (thats SharpCap)! Learning how to use it takes time, and may or may not suit the way you think. Some hate AT and love SC saying it is soooooo easy. The way my brain works I found AT very simple to use and struggled with SC! LOL! Bottom line .... dont underestimate the software and its learning curve and length of time before you get a good result. Re 224 sensitivity vs GP Cam sensitivity vs SCB sensitivity? ... Are you near to any places where there's an astro club? Ask members if anyone has a 224 to attend a club meeting so you can try it out? Ditto is anyone has a 0.5x 1-1/4" reducer. Actually, you should probably get a reducer to speed up the exposure time as even with your GP Cam and also the SCB, you'd get big benefit from that You may find that a reducer is all you need! The 1-1/4" 0.5x GSO brand reducer (and all brands who sell a rebadged GSO 0.5) will let you get the same image brightness in a quarter (to at worse half) the exposure time required at your full F ratio of your ED72. Very short (but still bright) images are good to find and frame stuff, as well as plain fun to watch ala those video links. But think about it ... let's say without a reducer on your ED72 that your Camera shots on a particular target are 15 seconds before you start to see field rotation blurry stars appearing in each frame. So with a 0.5x reducer on you'd get the same image brightness with just 4 second frames .... but it doesnt mean you have to shoot at 4 seconds! As you can clearly go to 15 seconds before you get field rotation. So with the 0.5x mounted, turn down the gain and increase the exposure back up to 15 seconds .... you will get more details at 15 seconds and at less gain and hence much less noise - so your stacking will yield better results. Cheers and hope it goes well for you.
  6. Disclaimer .... My fav cams for use as EEVA are actually Canon DSLR's combined with AstroToaster. With 7 years of experience using them, I reckon 4 frames of 15 sec at ISO1600 with your modded Canon 450D would easily get M27 (and have better detail and with nice sharp pinpoint stars) when used with AstroToaster out in the field at night next to the scope. I've done M27 with single 15 second at a dark site using Canon 650d and AstroToaster. BTW Your Sony Alpha may be even better with it's higher ISO's ... but the Sony's dont lend themselves as easily to in-the-field EEVA processing and stacking. Sony's need both a remote to control the camera exposure and ISO and intervalometer and also need a wifi SanDisk card to send images wirelessly to a laptop folder where you can tell AstroToaster to auto find and stretch them etc. But it is doable using a Sony ... just a bit of faffing around. However, you're chasing REALLY sensitive cam! OK ......... lets get onto that! The ZWO ASI224 has been regarded for several years as being very sensitive and so has been one of the most highly regarded cams for EEVA. The ASI183 also is sensitive and well regarded for very short EEVA. Both have small sensors and so will magnify heaps on any scope they are put onto. TIP: A 5mm sensor will produce a FOV like a 5mm Eyepiece on any particular scope. A 23mm sensor will produce a FOV like a 23mm EP. And so on. However, a small sensor is better for EEVA (IMHO) as they will work with most reducers (even heavy reduction) without vignetting, and this has a HUGE benefit ... it reduces the F ratio for the camera. This lower F ratio allows much faster exposures compared to using them unreduced. And for AltAz you need very short exposures! It's a testiment to especially the ASI224 but also to the ASI120 and ASI183 cameras that I've owned, that when I've sold them for one reason or another, I've ended up repurchasing another one to replace them down the track! LOL. I keep rebuying (especially) the 224, as I find more and more uses. Such as .... I am using my Star Adventurer and camera lens for REALLY widefield with them. They also (due to the sensitivity) make EXCELLENT e-finderscopes! If you load ASCOM and platesolving then you actually dont need a finderscope at all ... find target in stellarium, click to slew to it, then tell Sharpcap to platesolve using the main OTA cam and to slew from there to your target object and if it wasn't centered (or even in the FOV) then it will make the correction based on the platesolve and slew to it correctly. But ... when starting out you dont need to load all this stuff! I'm just giving you reasons why despite me favouring DSLR's for very good EEVA, I still buy very sensitive ASI cams for all the reasons in this paragraph. BTW most times I dont bother with platesolving anyway ... I run an ASI224 with a 55mm Canon lens as an e-finder and centre using it ... as it will show colour and faint stuff very quickly. Once centered I setup the DSLR in the main OTA confident it is then centered. This method allows me to use the very sensitive 224 e-finder to do my Skywatcher mounts star alignment and PA. Or (back when I had one, my Nexstar mounts alignments). Anyhow .... here's a link to a video down below showing a bloke using the ASI224 live ... does couple of globs first then moves to M57, and M27 ... you'll see the stars slew past as he slews to the objects and even when framing the object with the movement buttons you'll see it is live. His M27 is 4 second exposure! OK at 4 second for one exposure it is missing details .... but key to using that sensitivity is the software he is using (SharpCap) allows stacking. He doesnt show it, but when you can see a half decent single exposure image (like his 4 second M27) then how you stack is you click the Stacking button visible in that video on the top menu bar of that software and sit back watching the image get better and better. All while out there in the field next to the scope. Or as many do, with wifi and long cables sit inside in the warmth controlling the scope and cam outside. Or, down-under where I'm from, sitting inside in AC and away from the insects. Link to video is ... https://www.youtube.com/watch?v=O6n2z6rj_98 And this next one he is operating at F2 using hyperstar reducer so just 1 sec frames .... https://www.youtube.com/watch?v=iTgVT_WGThM
  7. Extremely nice shots Steve! Thanks, as I've been looking at the combo of 294mc pro and tri-filter for a while. Sorry, as I might have missed it in the first post, but what (Bortle etc) skies were you in?
  8. Great result ... makes me want to get the old Mallincam VSS+ out again! One question ... what is AS!3 ???
  9. Decisions, decisions! LOL. And .... if you raised the OBS one or even two metres off the ground all the above would change again! LOL All the best mate. Can't wait to see where you decide. Post up photos as you build ... cheers
  10. Thank you Martin for all your work doing that. Interesting read too that PointSources pdf.
  11. Out of all those specs Martin, how does one work out the sensitivity for one vs another camera? It's often stated to use a "more sensitive" camera if on Alt Az for instance, due the shorter exposure times due field rotation effects. So sure with a less sensitive camera/sensor you can just stack more and eventually get nice bright(er) image. But you have to wait longer for the stack as you are doing more. But if doing outreach, or 'true' VA (not really caring too much for quality and just want to see lots of stuff during the night) then you want something more sensitive (so you don't have to stack much to 'see'). So, can you work out 'sensitivity' for those cameras from the info in the table?
  12. There's probably some smart way to calculate it all. But being not smart enough for that, I made up a jig. Imagine a plank of wood on top of two saw-horses down by the bay near where I live. The whole xx12 tube lay on top horizonally and pointing across the bay towards the port facility on the other side of the bay about 5 km away. The camera was inserted into the focuser (along with its 2" Baader MPCC Canon fitment) and (importantly) with the focuser wound out about a two centimeters to allow for any possible adjustment around the focus point later on. But ... the Orion struts were not holding the primary and secondary tube assemblies apart on that "jig"! The primary and secondary tube assemblies were resting in a 'bay' created by two lengths of straight timber screwed onto the plank. Thus gravity held the primary and secondary tube assemblies hard against the horizontal plank/timber guides, which being straight still held the optical alignment between primary and secondary mirror cells. I simply moved the secondary mirror assembly containing the focuser/camera slowly towards the primary cell until I got focus. Then I measured the distance between primary and secondary assemblies. Back home I reassembled the xx12gt using the proper struts and checked that measurement to find I needed to drill those second holes exactly 40mm towards the primary mirror to work for my Canon 700D. So the four attachment plates on the struts where the struts attach to the secondary mirror cell, needed a second hole drilled 40mm closer to the end pointing to the primary mirror. I took the struts to a local machine shop where they had proper drill presses, to guarantee each hole was the same distance from, but still aligned with the centre of the original holes. They were so intrigued with it all, and in disbelief that an amateur telescope could be THAT big, that they didn't even charge me for it! LOL. Note that it was not required to perfectly optically align the primary and secondary cells in the "bay" on the plank. As long as the camera showed focus, and the focuser knobs allowed me to wind up to then past the point where the camera got the best focus on that 'rig', that's all that was needed. For once the struts were drilled mm perfect at the machine shop, and I then did a collimation, the focuser would look after that last absolute perfect slight adjustment to bring it properly to focus out there in the dark. Leastwise, it worked out well for me. Cheers
  13. I've got the same GoTo DOB as you ... XX12GT. I drilled a second hole in the strut secondary are as per the photo's ... brings my Canon DSLR APS/C camera to focus nicely. If I used EP's init to do alignment or visual I simply stick a small 2" extension tube in and EP's will also then come to focus. EAA with the APS/C sized sensor worked a treat with EOS Utilities controlling camera ISO and exposure times. Setup EOS Utilities to save images to a folder monitored by Astrotoaster on a bootcamped Macbook. Astrotoaster uses DSS in the background to do the stacking (if necessary) and Toaster to do the AP-like stretches so it made the EAA image happen. None of my EAA shots from that DOB available unfortunately, as when Photobucket went to a cash-to-use model I declined. And those buggers simply wiped the account photos and all. However, my example inspired a friend of mine in New Zealand to do the same. Link to his shots below using DSLR on Skywatcher DOB for years with all sorts of scopes piggyback on it. Being adjustable struts he did not have to drill any holes but simply adjusted the length via the adjustable set-point knobs. He rigged a counterweight system on a adjustable rail so the Alt motor could see the load as balanced ... and so would still work in Alt. He carried ED80 + a second DSLR for widefield, and whole bunch of piggybacked scopes as per the photos of his rig down in the link below. The APS/C sized sensor gives a good 1.2 degree FOV on the 1500mm DOB. A great view of most Messiers. The stacking capability of toaster allows much more SNR in the final stacked image which allows some very good shots from the combo. BTW. You can also get bigger primary mirror bolts to "push" the primary mirror into the OTA more thus pushing the focal point further out the tube (instead of modding the XX12GT struts). My photos showing how I moved the focal point further outside the tube thus allowing the DSLR to come to focus. https://flic.kr/s/aHskZvmNDE Very long video when I first tested that the shortening of my struts had worked nicely. It had reached focus and was amazingly sharp ... live HD desktop capture of Moon surface at Canon EOS Utilities 5x sensor zoom. Dont watch it all as its 15 minutes! https://youtu.be/LQJ9WyE2nmA Friend in NZ showing his amazing balanced DOB using moveable counterweight system ... https://flic.kr/s/aHsksGCqYM His amazing DSLR images using that setup ... https://flic.kr/s/aHskGspbb6
  14. Ditto on everything stash_old says! I've had Samsung SCB2000, various Mallincams, various ZWO's and IMO nothing beats the simplicity and very sharp almost AP results using DSLR on f/5 and lower OTA's. Link to flickr album below ... 3 partial nights viewing using 9 x 60 sec frames ... all screengrabs showing the image on screen in-field at time scope is slewed onto targets and like stash says ... you see the image right from the first frame and then watch it better over the subsequent shots. Usually I set toaster to single shot processing and take single iso12600 frames of around 5 seconds in order to find/frame the object nicely. Then when its framed nicely I set toaster to stack and set the dslr to shoot 9 x iso800 or iso1600 30 to 60 sec exposures. I adjust a few toaster color adjustments and expand gradients after the first shot comes in. Then I sit back for 10 minutes and watch it get better and better with each passing image. https://flic.kr/s/aHsm9Ld4SC
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