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Post by Deleted on Mar 26, 2014 14:51:21 GMT
I'm a fellow newbie and my current thinking and research is this: 1) Get the most stable and highest weight capacity mount in budget. Mounts retain value well on resale, so its hard to get a great deal, but if you go in a different direction, you can sell it easily. The cost of the mount may even be more than the cost of the telescope.2) Its not just the focal ratio / fastness -- is the combo of the focal length and the specs of your CCD. I leverage this website www.12dstring.me.uk/fov.php to get an idea of objects' scales and the field of view based upon the camera CCD and telescope specs. Not only can you select telescopes and cameras from a list, but you can put in your own specs if necessary. And I like selecting different objects from the menu to get an idea of scale. Have you looked at the VRC6 or AT6RC? Focal length isn't everything... aperture still helps with contrast and details. 80mm is almost half of 152mm. I agree with statement one whole heatedly. As for statement 2, I fall back to statement 1. Wide FOV will compensate for tracking errors, field rotation, and other PEC errors. If you have a good mount and possibly guiding you can go for a slower scope. Slower scope means you need longer integration to pull in the image which exaggerates tracking errors. In no way would a slow scope with a cheap Alt/Az mount be capable for anything other than planetary. However a super fast wide field scope on the same cheap mount may have some success with DSO's. If budget is the concern, never buy a slow scope on a cheap mount. I would buy just as you stated in point #1, buy the best mount you can afford and preferably a GEM. You can put a $100 cheap OTA on a nice GEM and produce wonderful views. But you can not put a nice OTA on a $100 mount and expect anything good. Whatever mount you do end up getting, buy an OTA that will perform with that mount. The cheaper the mount the faster the OTA should be to compensate. The video cameras out now do a good job of pulling in photons fast, but they also have small chips equivalent to a 5-8mm eyepiece. SCT optics are real good but also real slow, focal reducers speed them up to acceptable FOV. But for SCT's I would stick to the high end meade and celestron with quality mounts. The absolute cheapest mount I would ever use for video would be the celestron SE mount, and fast OTA or SCT with heavy focal reduction. But I would recommend for good results a eq5 or better class mount (AVX, Slywatch, Lomsdy, etc) with a fast ED refractor or an SCT with focal reduction. People are also having great success with the Meade LX/LS series and Celestron CPC series fork mounted SCT's. Sorry for the rambling rant, just trying to help newbies before they waste hard earned money. Hemmi
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Post by Rick in NWArk on Mar 27, 2014 2:16:23 GMT
Yep, thanks for the reply Hemmi. I don't want to hijak Cloudyne's thread ... just passing along intel I have come across. I'll post my search in a different thread, as I may have a different situation from Cloudyne.
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Post by Deleted on Nov 14, 2014 21:36:06 GMT
Until I can get a good deal on a 5 or 6SE this is my main choice at the moment. I think I have it all covered to get started. If you think there is something I need to add please let me know. Celestron NexStar 102SLT 102mm Astro Video Systems DSO-S (package) www.astro-video.com/dso-s-entry-level-camera-system.htmlAntares 1.25" 0.5x Focal Reducer EZCAP.TV 116 EzCAPTURE USB 2.0 Video Capture NexStar RS-232 Cable - Item # 93920 Cable, USB to RS-232 Converter - # 18775 AC Adapter For Celestron NexStar SLT The SLT mount's stability is quite good considering it price; however, the tripod can cause several issues. Fortunately they are easily mitigated. The tripod can actually lean and follow the mount around in azimuth. You can't see the leaning with your eye but a good bubble level will show it. The leaning can be sufficient to prevent a successful alignment. The fix is to simply tighten the bolts that hold the upper tripod leg sockets to the tripod head. The tripod is the source of what many consider excessive vibration. The problem is the very soft plastic used for the upper tripod leg's upper and lower leg sockets. The tripod legs are attached to the leg sockets with two inline rivets. These rivets allow a considerable amount of torsional movement. The solution is to inject super glue or epoxy into the very tiny almost microscopic gap between the tripod legs and the leg sockets. This will stiffen the tripod considerably; just don't get super glue on any moving parts. Always install and lock the accessory tray and if at all possible don't extend the extension legs. I'm just getting started with video astronomy and don't know how a video camera reacts to a fringe filter use to reduce chromatic aberration with a refractor. I do know how a DSLR reacts and the result is not worth the price of the filter... the fringe is still there but slightly reduced. You mentioned you were not planing to carry your kit with you when you move to Germany. You ought to be able to hand carry a 102SLT (OTA and SLT mount). The tripod can be taken apart and stuffed in your luggage. I've carried telescopes as carry-on between Europe and the USA several times with no issues. If you want an economical 80mm short tube f/5 refractor on a fair GOTO mount take a look as the iOptron Cube E R80 (just don't extend the extension legs): www.ioptron.com/index.cfm?select=productdetails&phid=6810848b-bd0b-4048-a7c9-f79bbdb13767 If I were doing what you are doing, I would spend as little money possible on a mount and telescope. You can get good telescopes and mounts in Europe albeit for a few more dollars than in the USA. The same is not true for video equipment; get the best video camera and equipment you can get while you are in the USA and don't forget the NTSC/PAL standard differences between the USA and Europe.
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Post by scopesnc on Nov 14, 2014 22:27:06 GMT
I would go with what Lee said. Don't go cheap or you will wish you had not later. Save up. Make no rush about this. Take your time and get there right the first time. Just my 0.0002 cents worth.
Jim
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Post by davy on Nov 14, 2014 23:20:57 GMT
I would not worry too much on what system you can get camera wise pal/ntsc your video grabber will convert It to a digital signal on your computer. .scope wise if your worried about c/a go for a doublet I could not afford one at first and got the sky watcher st102 c/a is murder, I came into some cash soon after and bought the skywatcher ed80 brilliant scope. .highly recommended..
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Post by Dragon Man on Nov 15, 2014 10:53:54 GMT
I totally agree with Davy. The little ED80 is a remarkable scope. Especially for Video because these cameras make the ED80 work like it's a ED150. I do 99% of all my Video Astronomy with my ED80 and I have a large choice of scopes to use. It just simply does it better than all the others. Here's what I have to pick from and I still chosse to use my ED80:
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Post by scopesnc on Nov 15, 2014 11:47:13 GMT
UH just a guess , but would lazy have anything to do with not carrying out the larger scopes to use ? Some of us do know you Ken. LOL
Nah just joking. I have seen Ken work his magic with that ED80. It is a wonderful OTA for video, there is no doubt about it. There are certain OTA's that just seem to work well for video and that little ED80 is one of them.
ScopesNC
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