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ronin

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About ronin

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  1. Few years back on CN they said the 80mm refractor was likely the best all round scope. May not have the biggest aperture nor the greatest magnifications but they deliver sufficent light collection and sufficent magnification for 90% or more of what people actually require. They are easy to transport, views are good, they image and with a solar filter or herschel wedge they do solar well. The ED version is not too costly either, being only a doublet (ggod one), also that reduces the weight. Always seems almost a crime that when anyone asks "Which scope?" the 80mm's are generally ignored and something large is suggested, especially when it is a persons first scope. For a first sacope an 80mm (or there abouts) seems the ideal do everything option.
  2. WO seem to always go for claiming n.9 refractors. They seem to operate of the idea that people like to see "fast" refractors, appeals toi imagers more. There is a new Astro Tech that came out the same time as the WO 61, same glass same focal length but AT have said it is 60mm dia so that make it an f/6 scope not an f/5.9. The ZS61 is another example and I think even the older Megrez 90 was the same, cannot recall the GT81 but would half suspect that to be another that was an f/n.9 scope. Willing to bet the WO and the AT are exactly the same. When everyone brought out a 100 degree eyepiece I recall one manufacturer designated theirs as 101 degrees - may have been WO or Meade. If you look at the link to the melt frequency then FPL-53 is fairly low whereas FPL-51 is one of the highest melt frequency they do. So I would doubt that FPL-51 may be phased out. FPL-55 is now more frequent then FPL-53. Isn't Schott FCD-100 an almost direct replacement for FPL-53 now. Which may be why ES use it and not FPL-53, if there are concerns that FPL-53 may slowly get removed.
  3. Evostar 90, and a couple of plossl eyepieces. Not sure about a mount as they are generally on a manual one. Often people want a motorised mount if nothing else just to track an object. So in many respects the mount is more a problem then a scope. But the Evostar 90 will show Jupiter and Saturn, Saturn needs around 120x to 125x as a minimum. Do not go getting a small focal length eyepiece like a 4mm plossl - they are a waste of time. An 8mm is likely as small as makes sense. There are 7mm Celeston X-Cel LS eyepieces which may operform but was you get smaller the cut off in performance is sudden. Maybe consider a moubt upgrade later when he is familiar with the scope and both he and you has a bit more experience to work with. But the Evostar 90 is a good option. Alternatives may be the Bresser range, they have a similar 90mm but I think a 102mm get the long version, I have the short version and good for wide not ideal for highish magnification for Saturm. Not sure which is available in NZ. The 102 Bresser is likely more attractive to your son.
  4. Sorry not gong to happen with an ETX-90. Owing to the diameter and the general magnification(s) I would doubt that even M42 under dark skies would deliver any colour. Equally you are Australia but I am not aware of anything that would be brighter in your skies. Photographing objects will be difficult. The ETX is really not built to have someone attach 3/4Kg DSLR to the rear. Which in many respects puts DSO long exposure imaging out of it. You could attach a webcam and get images of planets. You get a video of these then select and stack in something like Registax or AS2. For more idea ask again. IF you bought something like the ZWO cameras they take video and long exposure and are small. So then DOS imaging to some extent may occur. Only MAY. For this you would need to put the ETX on an EQ "mount" - did it come with a Meade Tripod ? Then you set the mount type in the ETX menu to Equatorial. Then aim the scope mount (the 2 fork arms" at True South (for you). And do the alignment. (Think that strictly this may be unnecessary owing to the Eq setup but do it mainly for the goto feature). After all this you have an Equatorial tracking scope, and a small camera capable of say 15 second exposures (the scope is likely not going to track accurate enough for longer). Bit involved and not the best but that is about it. Guess yo do not have many problems with light pollution.
  5. Going to say a it borderline. I sent a 6" SCT scope to M1 some years ago and there started the arguement. I was 60% sure that there was a faint something in view, the other person said I was imagining it all. Agreed your scope is bigger but I suspect you could be in a similar position. On all the faint ones (which can be the majority) getting them in view and actuall "seeing" them does not always correlate. Finding M31 by eye is another people cannot see it until it is pointed out and they have done it a couple of times. In yours I guess the first thing is keep the magnification down, a reasonable 32mm or 40mm plossl eyepiece. TV or Vixen comes to mind. The next is get to M1 via a close by star. Maybe Aldebaren centered then a short hop to M1. Use the PAE or Sync feature. Reason for this is simple the scope may have a view of say 1 degree but that is actually +/- 0.5. If M1 were 0.7 degrees off of center then it is not in view. Have fun, if you really want to "not see it" then take a 6 year old with you, their eyes work better. Gets annoying when oine announces "That looks great!" and you are wondering what they are talking about.
  6. Star Atlas

    Do you mean a Star Atlas or an Astronomy Guide, as in a guide to the constellations etc. Something a bit less intense/serious? Ask this as I have a couple of the Star Atlas's and to me at least they can be a bit much. My "Constellation" guide is The Monthly Sky Guide by Ridpath and Tirion. However I guess this may be of limited use to you as the book it based around the 50N Latitude. For a PC use Stellarium or Carte du Ciel (CdC) and set your location. Owing to you being in Malaysia be a little careful of recommended books as most of us here will be familiar with the Northern latitudes and some may be non-applicable to you.
  7. Shouldn't Sedna be a Planet?

    It may well be a part of the Oort cloud in whch case it will not have cleared it's orbit, and likely never will be able to as it will pass outside of it in its orbit, the Oort cloud bodies will "refill" the orbital path and the next time round either the path is filled or it takes a different path (most probable) and ploughs through more Oort cloud bodies. In effect its orbital mpath is not cleared. So it fails.
  8. Please Help Me Upgrade My Mount...

    Going to ask Why? Unless the imaging intention is to use the Edge HD 800 more the other 2 scopes are well within the capibilities of the HEQ5. Which leads to the question of how easy do you find hauling the Edge HD on and off a mount - assumes it is not to be permanently mounted. If it is then what are the others to be used on? Might build a pier for the mount and not use the Edge HD a lot however it seems you could be considering a fair outlay on a mount for one scope that may not get a great deal of use.
  9. So what longer focal length scope are you thinking of ?
  10. 60% seems the accepted normal. Wonder if like me people see an item, fair cost but it is outside the area and so decide not to go further. Have seen a few bits that if I could drive to them easily I would consider. Also I have just about all I need. Yes a Super Mega Wide eyepiece sounds nice but I do question if I would really care. Astro equipment is getting costly now and in some instances 60% of the present cost manages to get close to the original cost. Just been a bit gobsmacked to see the present cost of TV plossl's. And even 60% of the present cost seems a fair chunk - close to £85, and I suppose like John says uncertainty is a big factor.
  11. We're going back... it's official!

    I would also say that returning to the moon actually has little relevance to a Mars mission. Moon is a fairly short 3 day trip, Mars is a long term duration. If going to Mars then a stop off at the moon is very negative - moon could be useful for a gravitation slingshot I suppose but a return to the moon is irrelevant to that.
  12. I would say that the "normal" 30/32mm plossl would be the best option. You might find that a 40mm plossl will give a fraction more, but it will be so small as to be kind of insignificant. When I got my 105 Mak I recall that I worked out that the 40mm managed a fraction more. I bought the 40 therefore. I suspect that a 2" eyepiece is not an option of the Skymax. Problem is some say 30mm some 32mm and then comes the FoV which can be 50 or 52 degrees according to whichever manufacturer. And to be honest I am not sure how true/accurate each claim actually is. I have seen identical looking plossl's with fractionally different claims. If you consider say a 30mm and 50 degree plossl (both nice round values) then the numbers work out an identical field of view to you as the BST Starguider. It all can become a bit involved for what could be little return. Looking at TV plossl's the 32mm will give a field of 1.28 deg, the 40mm will give 1.376 deg. Sort of 0.1 of a degree, which was about what I found the first time round. Didn't realise TV Plossl at 32 and 40 were that costly now.
  13. The Sky at Night

    Bit agree with GrahamF, not so disappointing but seemed a bit "odd". First I have seen fro a whole - the snooker finished early. Did seem that it had not topic to focus on. Getting people "interested" is a little irrelevant. If they have no interest they are not suddenly going to go andd buy a scope and take the hobby up. Better to nurture an interest that sort of exists. Greenwich Obs is well lit up with light pollution. Not sure the explanation of the Aurora was fully correct, I was losing interest. I have noticed that explanations are not fully detailed the light comes from electron in atoms dropping energy levels. You can get the idea that particals just entering at the magnetic field boundries create it. They may be the cause but not the actual method. Maybe they need to realise that people who watch something like this may actually have an idea of what is going on. Another event was doing the same, I asked as things seemed a bit simple" and was told well they are just public visitors, I pointed out that some of these public visitors had travelled 20+ miles and all had come more then 2 miles so most or all would have an interest and so likely some knowledge otherwise they wouldn't be sat there. Noticed it started with Chris and Pete Lawrence.
  14. Wrong scope. You are thinking in Visual terms for what is AP. Mount HEQ5 will do, but the scope will be smaller anything like the WO Star 71 would do. NOTE the "71" not "250". 80mm is common in AP. So may I suggest a slight rethink. The best approach is to seperate visual from AP completely. To use a 10" for AP you will need something like an EQ8 or better a permanent observatory and permanent pier. Say this as I know someone that does use a 10" and that is their set up and even that tends to be a little "unstable". They are planning on a better mount. Last I knew up in the £5K to £8K area. You can share a mount between AP and Visual, but it need some thought. Not easy to share a scope. A WO GT-81 is good for AP but limited (maybe) for visual.
  15. For the basic intention then the Nikon is fine. The basic beinng that you take say 20 exposures of say 20 seconds each then head off and stack them in DSS. Might be a little simplistic but Canon were recommended initially as Canon supplied software for their cameras whereas others did not. How much you will or might use this software is a question. Assuming no use then no great difference. One internal difference is the IR filter, on a Canon their filter will pass about 23% of the incoming Ha and on a Nikon it is lower at around 15-18% - the curves I have are a bit out of date. Main reason for problems is likely to be settings on the Nikon. The whole thing needs to be in Manual, so you set the exposure length, the ISO and the focus. You also have to turn off the Noise Reduction. Sure they is something else in there that needs doing. Assuming you have an intervalometer (you will need one) then you need to set the Mode to "B" for Bulb (old photography term that got carried over), then the exposure length is determined by the intervalometer and after the exposure set a Wait time to allow the DSLR to perform all the required post exposure functions. Do not just get on taking the next exposure, there needs to be a time period for things like writing the data to the memory card. One thing to remember is that a DSLR was not intended for AP the exposures are too long and this causes problems, also AP tends to go for RAW files which are big. They will manage AP to an extent but you have to work with them. For stacking you will need say 20 or 30 good exposures and if possible 10-15 (say half as many) darks. Darks are "easy" same setting as the exposures, set the number of exposures to say half as many and press the Go button on the intervalometer then put the whole lot in a fridge and close the door, Make a coffee and at the end you will have Darks. Stick with just those for the early stages. If I recall DSS will stack jpegs so you could just collect standard images initially to get going and learn what is involved with the DSS options. It is a bit less involved at the start. You will have to track down all the setting for manual operation, they do tend to hide the things and occasionally in odd places.
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