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sxinias

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Everything posted by sxinias

  1. Hi, probably a little late in responding to your question but just in case others are interested. I do a lot of work with the ST80 and yes I do have the dreaded blue halos around stars. At one time I tried to get rid of the blue but now I pretty much leave it alone as it is part of the process with an inexpensive refractor. Here is a link to my flickr site that has many images made with a ST80 on either a SkyWatcher SynScan AZ goto mount or a 4/5SE mount in the equatorial mode. Joe http://www.flickr.com/photos/59237884@N08/
  2. I had a similar problem with my SkyWatcher AZ goto mount which is similar to your mount. Turned out to be a defective mountthat was replaced by the vendor (Green Witch). The replacement mount worked great out of the box and continues to do so 6 years later.
  3. I once tried a Baader Semi APO filter with a Canon 1000D and an Orion ST80A. I made several images of Vega with and without the filter. The blue fringe was present with or without the filter albeit slightly paler with the filter.
  4. Congratulations on your new telescope and first light report. It's one of the best reports I've read. Enjoy your new baby.
  5. Hi, I have a SW SynScan AZ GOTO mount which is pretty much the same as the SLT mount and has the identical tripod. While I have not had the mount on a pier, I do put it on my CG5 tripod occassionally. The mount undergoes a transformation on the CG5 tripod and should behave similar on a rigid pier. Vibration is not existant and gotos are very accurate. I can even put my 8 inch SCT LX200 OTA on it and obtain accurate gotos. The rigid mount greatly facilitates focusing, needless to say. As far as the tripod goes, there are some simple things that improve it. Tighten up all the nuts and bolts, especially the bolts that attach the tripod leg sockets to the tripod head. Inject superglue or epoxy in the paper thin crack between the upper tripod leg and its upper and lower sockets beiing careful not to get glue on any moving parts. Always have the accessory tray installed and locked in place. Do not extend the extension legs any more than need be. 30 % at the most. You can remove the extendable legs and wrap them to increase their diameter and reduce wobble. The above will not eliminate vibration but does dampen it and reduce decay times.
  6. I think you probably can put your Lyra 4" on the SynScan AZ goto mount with no problem. A little over three years ago, I put my C6S OTA on a SkyWatcher SynScan AZ goto mount and have operated it that way since then .. a home made 6SE in a way. The C6S OTA is at 10 pounds (4.5 kg). So far the mount has held up just fine. The only issues are related to the tripod which is less than stellar and required some modification to stiffen it. I have even attached a focal reducer and a DSLR to the C6S/SkyWatcher AZ mount and photographed some deep space objects. The weight with the camera is 12 pounds (5.4kg). Here is NCG 0253 taken on 9 Nov 2012 with the C6S on the Skywatcher SynScan AZ goto mount (123 frames stacked for a total time of 58 m 40 s, Canon EOS 1000D at 1600 ISO)
  7. Lovely. I do admire your patience ... 7 hours. Congratulations.
  8. Nice shot. The wide angle star field adds a lot.
  9. My first DSO was the Sagittarius Star Cloud M24 taken piggyback (Canon 1000D, an old 55mm f/2.2 SLR lens, SkyWatcher AZ GOTO mount, 1600ISO, 20 seconds). Six months later I captured M1 (total exposure of 17 minutes, C6S with CG5 mount and 6.3 focal reducer, Canon 1000D at 1600 ISO. This was also my first shot using a polar aligned equatorial mount ) One year later M8 (Canon 1000D, 1600 ISO. Total exposure time 30 minutes and 56 seconds, C6S OTA with a f6.3 focal reducer using a SkyWatcher SynScan AZ GOTO mount and tripod). My favorite M45, Pleiades Rising, piggy back taken 3 months after I started (30 second esposure, 800 ISO; 55 mm f/2.2 lens, Canon EOS 1000D camera, SkyWatcher SynScan AZ GOTO Mount)
  10. Thanks for the roses. Photography with a SkyWatcher AZ GOTO mount and its shaky tripod is a challenge. Basically I am curious at what can be done with mounts like it. Last year about this time, I was just starting down the road of astrophotography. I decided to see what a beginner, photography wise, can do with mounts like the SkyWatcher AZ goto, SLT, DS2000, and 4SE. At the time it seemed like a good project to pursue ... and still does as I am having a ball of fun doing it. My C6S or 2045LX3 OTA (4 inch SCT) on my CG5 is where I will end up eventually. In the mean time I am learning a lot of techniques, etc. that I can use. I will also have the capability of "grab and go astrophotography" so to speak using lightweight, portable equipment. There are a lot of limitations and issues using entry level az mounts for astrophotography. It will never compete with digital images taken with traditional equipment. However, I think that it can be very competitive with the film guys. At the moment, I trying to use the 4SE mount in the equatorial mode. The mount has one serious design deficiency .... there is no practical way to make fine adjustments in azimuth and altitude needed to do a precise polar align. I've modified the wedge to provide a way to do a fine altitude adjustment but azimuth still requires actual mount movement; a hit and miss proposition. I obtained three minute unguided exposures with it on one occassion but have not been able to repeat or even come close to that time since. Too bad I didn't use that luck on a loto ticket instead. Typical unguided times range from 30 seconds (easy) to one minute (not so often) dependent upon the luck of the polar alignment. The only advantage I see with the 4SE mount in the equatorial mode is that you can do short exposure astrophotography within 30 degrees of the zenith and not worry about field rotation. This in itself is a great advantage over azimuth photography as it does give you the capability to photograph anywhere in the night sky and to photograph where the atmosphere is the thinnest. The 4SE in the Azimuth mode is better than the Skywatcher AZ GOTO (SLT) mount as it has far less vibration issues from tracking and from the tripod with field rotation being the governing factor for most of the sky. I have also tried Meade's DS2000 mount with a Meade 2045LX3 OTA (4" SCT). I was not able to do anything with it due to the way the mount tracks objects. Hopefully someday I can beg, borrow, or steal a SkyWatcher EQ3 goto and see what it can do. The Celestron SLT mount is so similar to the SkyWatcher SynScan AZ goto mount that I think, but don't know for sure, that the charateristics of the two are the same. Dark skies, don't I wish. I'm located on the edge of Athens' urban area. However, the sea is to the south of me and when the humidity is low and the moon is not around, this the summer I can some details of the Milky Way as well as a couple of Messier objects in the star cloud with my eyes. After objects pass the meridian, forget it as the light glow from Athens drowns everything except the brightest stars. One good fallout from Greece's economic crises is the local government does not have money to replace street lights when they burn out ........ A year ago, taking any photos from my home would have been impossible due to the street lights and forget about seeing the Milky Way. The vignetting problem is most likely from the Hirsch 6.3 focal reducer as I don't seem to have the problem when I don't use it. This could be an exposure issue though. However with 16-20 second exposure times, I need as fast a scope as I can get. I'm fairly new at photography and, other than using dark frames, have not yet ventured into other corrections. That's on the list and thanks for the recommendations. I'll certainly look into them. At the moment trying to figure out the mysteries of CS5 is keeping me occupied. Yes, the exposures were 16 seconds. Statistically 16-20 seconds is about the longest exposure time I can obtain with the SkyWatcher AZ goto mount and have a 80% or so probability of getting a good shot without vibration from tracking gears, wind, dangling camera strap, breathing too hard, etc. I also wanted to reduce field rotation as much as possible. At my latitude, if I stay about 30 degrees away from the zenith, I can get 30 seconds or more exposures with 0.10 degrees field rotation. Unfortunately, this removes a big piece of the sky where the atmosphere is thin for photography. My camera is a stock Canon EOS 1000D as it came out of the box. One thing I have learned; 100, 16 second shots stacked are not the same as 10, 160 second shots stacked. 16 to 20 seconds is not much time to capture a lot of photons and the exposures are chronically underexposed. I use 1600 ISO even though it adds noise. I had hopped the 6.3 focal reducer would allow me to go down to 800 ISO but 1600 even with the focal reducer seems to do better. I do cull out poor exposures during stacking as they only tend to add noise. AZ photography with a tracking dob. The wind is an enemy. A lot of sail area to catch the wind. Back focus could also be an issue. However, if you have a DSLR, you are only risking the price of a t ring and adapter. I've seen some shots on one of the forums, I forget which one, where a guy got some neat photographs of some Messier objects with a DOB photographing through the eyepiece. Here's my M20. Photograph taken on 27 June 2011 with a Canon EOS Rebel XSi (1000D), 1600 ISO. Total exposure time 41 minutes and 7 seconds. Telescope was a Celestron C6S Schmidt Cassegrain Optical Tube Assembly with a f6.3 focal reducer using a SkyWatcher SynScan AZ GOTO mount. I'm thinking about going back and processing it again.
  11. M 8, The Lagoon Nebula located in the Constellation Sagittarius taken on 26 June 2011 Equipment: 1. SkyWatcher SynScan AZ GOTO mount and tripod 2. Celestron C6S OTA with a Hirsch 6.3 focal reducer 3. Canon EOS 1000D DSLR Image 1. 116 exposures 2. 30 minutes 56 seconds total exposure time 3. 1600 ISO Software 1. Deep Sky Stacker 2. PhotoShop CS5
  12. What can you do with 30 second exposures? 30 seconds is not a lot of time but you can do many DSOs. I attempting to do the Messier List using an azimuth mount and am limited to 20 to 30 second shots. The dimmest objects I have captured to date are M51, M57, and M104. One thing to keep in mind, unless you have a computer controlling your camera, sitting out at night with a remote shutter switch in your hand taking a two or three hundred 30 second exposures is not very exciting. Also noise is a problem as 20 to 30 seconds is not a lot of time for a camera to capture information.
  13. Congratulations on your new telescope. You have a good one. If your mount still works in azimuth, then you probably did not damage anything. Even though the manual says you can manually move the mount in Altitude, I never do as I figure there are only so many such movement in the life of a clutch. macavity's suggestions are excellent. Minimizing tripod wobble. Tripod wobble is a common source of goto error for the SkyWatcher AZ GOTO mount as well as its sibling, the Celestron SLT mount. Fortunately it is easy to fix. Simply tighten all the nuts and bolts on the tripod keeping in mind the soft plastic fittings and low quality steel. Next, do not extend the tripod legs more than about 25%. Be careful tightening the leg clamps. It is easy to over tighten them and pull the brass threaded insert out of the soft plastic leg fittings. Balance. Use a round object like a pencil. Take the scope off the mount. With the diagonal, finder, and 25mm eyepiece attached, place the telescope on a table resting on its dovetail. Place the round object under the dovetail and find the spot where the scope balances. Mark the balance point on the dovetail ( a small dot made by white fingernail polish works fine) when you put the scope back on the mount, have the balance point in the center of the mount's dovetail saddle. The balance point will move a little as you change eyepieces but is not enough to worry about unless you are attaching a camera, etc. Level. your eye is good enough. The mount on the Skywatcher 127 SynScan is very rugged and accurate. It is capable of carrying a 5.5 kg load with no difficulty as long as the load is balanced. I've read reports of people placing 6.8 kg loads but have never done so myself. At present I am running an 8 inch LX200 OTA on my SkyWatcher SynScan AZ goto mount. The mount has no problems with it but the tripod does so I am using a CG5 tripod. In fairness, the mount and tripod are going on their third year of service. You can only tighten tripod nuts and bolts so many times before the soft plastic fittings woller out, etc. The mount is also suitable for photographing, not only the moon and planets, but the brighter DSOs as well. You take multiple exposures then stack. While you can not do as well as the people do with more suitable mounts, you can get fairly decent photographs that compete very well with the film guys as long as you stay about 30 degrees from the zenith. you are limited to 20 to 30 second exposures due to field rotation, mount induced motion, and tripod vibration. see: http://www.flickr.com/photos/59237884@N08/
  14. Tyr, Hi, I did nothing to the SkyWatcher AZ mount. Firmly but not overly tightening the mounting bolt seems more than enough to hold it firmly on the tripod. Currently, I'm in my photography configuration. My C6S is back on the CG5 mount and my 8 inch SCT OTA is on the SkyWatcher mount and SkyWatcher tripod. The SkyWatcher mount and tripod are going into their third year of service now. The mount is as strong as new but the tripod is showing wear .... its soft plastic fittings are the problem as you can tighten metal bolts so much before they pull through, screw holes enlarge, etc. The impact of this is I can no longer control tripod flexure and my goto accuracy with the 8 inch SCT using the SkyWatcher tripod is not as good as it once was. I often have closetos.. just out of view in a 32 mm eyepiece. However, it's still good enough for my needs. I know that the tripod is the problem because the mount's accuracy on the CG5 tripod remains outstanding. I use the C6S for photography because the way I've attached a dovetail to the Meade LX200 OTA is not adequate for photography (one screw on either end). This causes a light rotational movement which is difficult to correct and not good for a photograph but is something that you will never notice visually. The C6S is a pound or so lighter and that also helps. The other night, just for the heck of it, I used the SkyWatcher mount and tripod with the 8 inch SCT attached for a photograph of M57. I think it came out fairly well considering the mount and tripod used. I took a half hour total of exposures but only 6 minutes worth were good enough for DeepSky Stacker to process. edit: I just noticed you have the Celestron SLT mount. I think that anything mechanically that applies to the SkyWatcher AZ mount and tripod will apply to the Celestron SLT mount and tripod as they are essentially clones of each other.
  15. Deep Sky Stacker requires stars to align frames. Your shots of Saturn may not have any. Under advanced in the register setup. Adjust the sensitivity until you are getting 10 to 20 stars. If you have to go down below 4% to do this, either you have no stars or your frames my be not exposed sufficiently for the computer program to register them. With a Canon 1000D, why are you trying to stack photos of Saturn? It's capable of capturing Saturn without the need to stack.
  16. It just depends upon what you are photographing. You can take numerous short exposures, digitally combine them into the equivalent of one single long exposure equal to the total time of the short exposures using a process called stacking. Ten 10 second exposures stacked are the same as one 100 second exposure. Several computer programs are available to do this... one of the better being freeware ... Deep Sky Stacker. There is a limit to the lower duration of the short exposures as too short may be insufficiently exposed for the computer program to register the shot. These computer programs can also remove noise, adjust for the earth rotation, and other attributes. This process, multiple short exposures stacked into one long exposure, allows owners of azimuth mounts to photograph deep space objects as exposure times with an azimuth mount are around 30 seconds before field rotation becomes a factor. It even allows people with inexpensive mounts and tripods to capture deep space objects as they can discard the numerous exposures that are not up to par and only use the exposures that are good.
  17. A lot of excellent suggestions and a few that don't apply to the SynScan AZ mount. MOST IMPORTANT: The tripod is a major source of goto error. Watch your bubble level and do a 360 degree azimuth slew. If the bubble follows the tube then your tripod is flexing. Even though the bubble may stay near and inside the centering circle the flexure is sufficient to mess up the alignment and gotos. Tighten all the nuts and bolts on the tripod. The other source of movement on the tripod is rotational movement of the tripod legs in the tripod head leg sockets. This movement is very slight but gets magnified. Solution ... I epoxied my legs to the sockets but before that slipped some toothpicks in the very tiny crack between the legs and sockets. Shirt collar stays will work too. Always install the eyepiece tray on the leg braces to increase rigidity. The mount is not really fussy about being level ... eyeball will do just fine. Also, as stated in the manual, the orientation of the telescope at power-on is not important regarding alignment but .... on the other hand as someone said, it eases the process. People have their own ways for aligning the mount. I like to park my scope after using it. The next usage I eyeball level the scope and point it north when I power up and by pass alignment. I then do a goto to Polaris, switch to the alignment mode and use it as the first alignment star. Any other star would work, I just use Polaris. Makes the alignment process a little easier. I've never had any success with the SynScan bright star align and use the two star alignment Polaris makes an excellent first alignment star; stars near the zenith are poor choices as alignment stars Centering the alignment stars is important ... defocus and use a higher power eyepiece than a 25 mm ... 9 to 12 mm works Overall time for the alignment: Don't know but often wondered. Weight. Not a problem with the SkyWatcher AZ mount. It is a rugged workhorse of a mount and can carry 12 pound (5.5kg) loads all night with no problem. I use mine for my 8 inch LX200 OTA and a C6S OTA with a Canon DSLR attached with no difficulties at all. The trick is to keep everything balanced. Been doing this for over two years now. My only issue with the 8 inch SCT is tube strike at altitude greater than 82 degrees. Direction of the last azimuth and altitude slews during the alignment process. I find that the gear slop in the NexStar 4/5 SE mount is an order of magnitude greater than that in the SkyWatcher SynScan AZ mount. The direction of the last azimuth and altitude movement with the SE mount is important because of this gear slop. I have never noticed the number, direction, or order of slews made to align a star to be a factor with the SynScan AZ mount. The altitude clutch on the SynScan AZ mount is much stronger than the SE mount. I have never attempted to put the loads on my SE mount that I put on my SynScan AZ mount as I don't think the SE mount can handle them.
  18. Does light pollution impact your seeing? Yes ... in addition to the impact upon your telescope, your eye may never truly become dark adapted making the situation even worse. For local light, a hood over your head works nice but can be stuffy on warm nights. Portable light shields work too. For London's skyglow ... difficult to combat. As you magnify your image you increase contrast but you also dim the image ... some people think the trade-off favors viewing ... others differ. I think a light pollution filter is marginal for a 6 inch scope. Viewing off a balcony does have its problems but you have to take what you can get. The thermal impact of balcony or rooftop viewing will make using eyepieces having focal lengths shorter than around 10 to 12 mm difficult. Heading to the country side and darkness once in a while will be a super treat where your 6SE can really show its stuff. Meantime, keep viewing to keep proficient in your viewing skills.
  19. Interesting decision as both have good and bad and people get excellent photographs with either. You can list the pluses and minuses of both types and fill pages writing pros and cons. But in all reality, which of the two types to get probably boils down to which type telescope you personally prefer; an emotional, not a technical, decision.
  20. SCT or MAK? Your questions: Which is likely to weigh less: SCT Which is likely to cool down faster: SCT Which will give the better views: It just depends upon what you are viewing and how well you keep the SCT collimated. The MAK is designed to keep its factory collimation. The SCT must be collimated by the observer from time to time. The Mak will be slightly better for objects benefiting from magnification and the SCT will be slightly better for objects that benefit from a wider field of view. The differences will not be that great and most can be taken up through eyepiece selection. The SCT will be better for photography.
  21. I find my Celestron C6S OTA on a SkyWatcher SynScan AZ goto mount is highly portable. I can pack the OTA, mount, eyepiece case, and other accessories in a large briefcase (will fit underneath the seat in front for air travel). My observation site is about a kilometer up around the mountain side from my house. I can easily carry my telescope, mount, tripod, viewing chair and other accessories to my observation site in one trip.
  22. I used a table top telescope for 20+ years ... a Meade 2045LX3 102mm SCT. You need a very sturdy table or vibration will drive you nuts. You also need something to take with you as sturdy tables are difficult to find in the woods and park rangers seem to put park tables underneath trees. Cheap solution ... by an cheap unfinished wood bar stool with a round seat without any contours for the rear and cut the legs down. A three legged stool is best but difficult to find.
  23. Jonathan, The 8SE uses a Vixen dovetail to attach to its mount. . As long as you purchase an equatorial mount that uses a Vixen Dovetail you will need to do absolutly no modification to your telescope. On a GEM the scope will be rotated 90 degrees from its position on the 8SE mount .... not a big deal at all. I switch my C6S between its CG5 mount and a SkyWatcher SynScan AZ goto mout all the time .... no modifications were needed. The 8 SE mount is not designed to operate in a manual mode.
  24. The ETX 80 will be the most portable, the XT6 will be the best for viewing, the heritage 130 the best compromise between viewing and portability, and the MAK90 left out in the pasture ... the least portable of the bunch. For viewing, the XT6 is the best followed by the 130, the MAK 90 with the ETX 80 in last place. Only the XT6 has sufficient aperture to start showing details of deep space objects, etc. Your concerns about the Heritage 130 are completely without any foundation. The scope is excellent. Get the XT6. It will show you the heavens in details the others can not do and it is easily transported.
  25. Peteuplink has it correct. BTW, humans have actually been exposed to vacuum in and have survived with no ill effects. For details see: http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html
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