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Borge
2010-Mar-06, 12:19 AM
Hey guys, I'm very new to astrophotography. Very new. I've got a Canon Rebel XS with a EF-S 55-250mm lens and it just isn't cutting it. Any suggestions for equipment for me? I'm on a limited budget, by the way. Thanks :lol:

PetersCreek
2010-Mar-06, 12:54 AM
Welcome to the BAUT forums, Borge. I hope you enjoy your time here. I'm sure someone (or several someones) will be along soon to answer your question.

Please take some time to familiarize yourself with our rules, linked in my signature line below. You might also give our FAQ a look-see. No worries with your first post, it's just that some things work a bit differently here than on other boards. Again, welcome.

Tinaa
2010-Mar-06, 12:59 AM
Moved to Astronomical Observing, Equipment and Accessories.

slang
2010-Mar-06, 01:04 AM
[...] and it just isn't cutting it.

This might be an obvious question, and it might not be.. It depends on what kind of results you want to get, and why your current equipment does not deliver that. What are you trying to image?

RickJ
2010-Mar-06, 01:10 AM
If you could post or link to an example and what you would like to improve about it, it would give us a starting point. The camera and lens are quite capable of great images. It's how and where they are employed that makes the difference. So as many details as you can provide, even if they seem trivial to you, would be a great help.

Rick

Borge
2010-Mar-06, 03:06 PM
Thank you for replying to my post, here are some examples of what I would like to shoot.
http://goo.gl/eZFP
http://goo.gl/2RqJ
http://goo.gl/2KFI

I would also like to be able to photograph distant planets such as this. http://goo.gl/6ngO

I guess this was sort of a blatant question though.

My current equipment doesn't fulfill this right now because I think it's a matter of focal length.

Miscellaneous information/ questions-

Whenever I take a picture of the night sky, the stars seem to have shifted, but I know it's not the fact that the earth is moving because they're in a weird shape, like the tripod had moved.

I typically use a shutter speed of anywhere from 2-8 seconds.

I would like the telescope to be compatible with both Canon and Nikon cameras so that I can let other people use it at my schools photography club.

My camera is 10.2 megapixels.

Hornblower
2010-Mar-06, 09:19 PM
Thank you for replying to my post, here are some examples of what I would like to shoot.
http://goo.gl/eZFP
http://goo.gl/2RqJ
http://goo.gl/2KFI

I would also like to be able to photograph distant planets such as this. http://goo.gl/6ngO

I guess this was sort of a blatant question though.

My current equipment doesn't fulfill this right now because I think it's a matter of focal length.

Miscellaneous information/ questions-

Whenever I take a picture of the night sky, the stars seem to have shifted, but I know it's not the fact that the earth is moving because they're in a weird shape, like the tripod had moved.

I typically use a shutter speed of anywhere from 2-8 seconds.

I would like the telescope to be compatible with both Canon and Nikon cameras so that I can let other people use it at my schools photography club.

My camera is 10.2 megapixels.

This is the first time you have mentioned a telescope. I cannot tell from your words how you had the camera mounted, or if it was being guided in any way to track the stars during the exposure.

I would need to see some of your images to have the foggiest idea what you have recorded so far.

RickJ
2010-Mar-06, 11:24 PM
This doesn't help. Everyone wants to take great pictures. I can't begin to cram 50 years of experience into a simple post. You certainly can't do any of what you show as examples with your equipment. Now you've mentioned a telescope but not what it is or how you tried to attach the camera to the scope. As you have discovered, getting the needed stability is not easy. Note too that standard DSLR cameras have IR filters that blocks the major light from emission nebula. For those you might want to have the Canon modified. Several companies do this.

As for equipment see the images at this forum and Cloudy Nights etc. Those usually show the equipment used. You will find doing it on a budget is very difficult but not impossible. There's a heck of a lot more to it than focal lengh or f ratio! An experienced images can do great work at any combination of these.

Sounds like you don't have the foggiest idea of what you are doing. So I recommend getting a good book on the topic such as Covington's "Astrophotography for the Amateur". Do you have a good knowledge of visual astronomy? If not you really need a year of this before you'll be ready to put to use what you read in the book. Also find a local astronomy club where hands on help will be available, you will need it.

Rick

Borge
2010-Mar-07, 04:18 AM
Alright, I didn't know that those were professional grade photos. I had no idea what to expect, I have no experience with this. What quality pictures would I be able to get with a Canon Rebel XS and this telescope- http://tinyurl.com/yh4dxkc

I know that this a very cheap lens and it probably will not get quality photos like you're used to.

glappkaeft
2010-Mar-07, 06:04 PM
Alright, I didn't know that those were professional grade photos. I had no idea what to expect, I have no experience with this. What quality pictures would I be able to get with a Canon Rebel XS and this telescope- http://tinyurl.com/yh4dxkc

I know that this a very cheap lens and it probably will not get quality photos like you're used to.

Honestly you can't do anything but take snapshots of the moon and maybe the planets with that combination. For serious astrophoto you'd need something like a sturdy motorized equatorial mount, a larger telescope and preferably a guide scope (+ guide camera and computer). This costs a lot and to make all this come together you need a lot of experiance and dedication.

If your camera comes with a decent lens you could build/buy a barndoor tracker and take widefield images but most kit-lenses are borderline at best.

RickJ
2010-Mar-07, 10:13 PM
Actually I've seen some good astro shots with the lens he mentions. Far better than that scope would offer. It's fine for a kid starting out in astronomy but not at all what is needed an adult let alone imaging. You won't find anything remotely like it listed in the details on the astrophoto pages.

Yes that camera and lens at 55mm would take nice star field shots in 10 minutes with a barn door tracker. i used a 2 hinge one driven by a wind up alarm clock for several years back in the 50's. But you do need to know basic astronomy just to polar align it, something I doubt Borge has.

The scope you show is totally unsuited to the task and optical quality is NOT one of the many reasons. Again, your lack of basic astronomy knowledge is the problem. It isn't equatorially monted, has no drive, doesn't have the stability or mecanical accuracy needed. Light baffling is lousy. I could go on but you get the idea. Actually the lens itself quite good I would expect. It's everything else that's the problem. Also I've NEVER seen a usable imaging scope sold on Amazon. That's for the asto illiterate about to be fleeced user. Deal with a reputable dealer like Astronomics, OPT and others. if you are not in the US a local club can tell you the good ones, I can't. You can't go by brand alone. Most major companies sell junk to Amazon and other mass marketers and usable stuff to telescope dealers. i imagine they make far more off the junk scopes as they sell so many of them. They get used once or twice then sit in a closet for years only to be passed on at a yard sale. You won't find much at all that's really cheap at the top telescope dealers but really cheap can't do what you want so that's good.

Think rock solid when imaging. If you touch it and see it move it is far too flimsy. If you grab it and it moves it is too flimsy. If you kick it and it doesn't move you are in the ballpark. If you are imaging at say 60x (I hate the term but will use it anyway) any motion is magnified 60 times. So even a movement you can't see would be fatal Sounds like from your first post that you can't even get the camera and its lens to hold steady at 1x. Not surprising, most if not all of today's inexpensive tripods aren't up to the task without modification. Now imagine how much harder this is with a telescope. The eye can tollerate small motions but not the camera.

Astro imaging scopes aren't cheap. Actually the scope can be only $400 but the mounting is that kills the wallet. it must track for hours precisely following the earth's rotation to about the same accuracy as following a rolling quater a half mile away! (Mine will do a dime at 2 miles) That's using a telescope for the lens. Just using the 55 mm lens on your camera you don't need that accuracy so a barn door tracker, properly aligned can track for 10 minutes with the needed accuracy. You don't buy these you make them. Internet has many pages of plans for single or double hinge types. Double hinge is better for your camera but it must be rock solid. Mine weighed in at 20 lb and could guide your lens at its full focal length but I had several years of astronomy experience with polar aligned scopes when I built it. You really need this before starting in.

Find a local astronomy club and attend a few star parties. There you will learn what equipment is needed. Also buy that book I mentioned. Both are required to accomplish what you want.

We experienced imagers make it look very easy. Years of experience go into making it look easy. It isn't. With an f/5 system you will need to hit focus to within about 55 microns. No way a cheap focuser on a cheap scope like you show could possibly do this. While my focuser is beyond your needs it alone cost 20 times what that entire scope you show costs! Doing astro imaging well isn't cheap if you go commercial. If you have the mechanical skills to make the gear it can be very inexpensive but will take hundreds of hours in the shop. Pay in time or money, I do a bit of both.

The book will show you what and how to get results that should please you at a rather low cost but some work will be required. No matter how much money you pour into it, without the needed skills and mindset you can't get much done. Richard Berry, then editor of Astronomy magazine coined the term "90 day wonders" for those that thought money could substitute for experience and learned the expensive lesson that it can't. You first must know the basics of amateur astronomy, this takes a year minimum with the help of a good club. Only then will you understand what is needed for the type of imaging you want to do. Each type has its own requirements and skill set. This is far from a one size fits all situation. I've spent over 50 years in it and have only become sort of proficient at a few of them. I've seen some do it in 6 years for their area of expertise. You aren't going to climb El Captian as a beginner and live. Same goes for trying to image say the Witch's Head in your second example. I'm yet to get a good one of it in fact. But that's not one of the areas I've really learned either.

Go slow, learn telescopes and basic astronomy, then you can undertake star field imaging with your camera and lens as you'll know what it can and can't image and what it takes to get an image.

By mounting it on a really good tripod or even a rock (most tables and the like aren't stable enough) and sand bag would work. Then trigger an exposure with a remote release. At 55mm for 15 seconds at ASA 800 or so that Canon should pick up some nice stars IF you are far from city lights and there's no moon. Use stacking software to align and stack a dozen or more of these to remove the earth's rotation and you should have a usable image. Try that with the constellation of Orion though the summer Milky Way will make a better target it isn't available right now. Good imaging requires good software as well as good equipment and knowledge how to use both. While free software is there it is limited. As i don't do DSLR I can't advise on software. It's in the book and there are likely DSLR users in a local club that can advise. Most beginners can't appreciate how vital a good local club can be. Even if you drive several hours to go it is well worth it. You will waste far more time not doing this.

Rick

Borge
2010-Mar-07, 11:12 PM
Thank you so much for clearing this up, I think I will buy that book you mentioned very soon. And I agree with you when you say that I need an understanding of astronomy before I can go into astrophotography. I think before I buy a telescope I will keep using the 55-250mm lens I'm using now. I live a good 6.4 miles as the crow flies from the nearest city, and it isn't that large. My property is also the second highest in our county, the highest is our neighbor. Also, what is a barn door tracker? I Googled it and from what I've found, it is something that turns the angle of your camera as the picture is being taken so that the stars don't make streaks across the image. Is that right? How would I go about hooking my camera up to a sand bag to stabilize it?

Borge
2010-Mar-07, 11:16 PM
Forgot to post this part.
Do you have a recommendation for tracking software?

RickJ
2010-Mar-08, 05:11 AM
Being well away from city lights is a great first step. I'm over 100 miles from a town over 8,000 population. Nearest town is 12 miles and has a population of 2. My township of 36 square miles had a population of 31 until a few days ago when twins entered the world a few miles from me. I doubt they'll be adding much light for a while.

Yes you found the barn door tracker. You watch a watch and turn a screw every 15 seconds or sooner by a certain amount depending on design. Boring but it gets the job done. I modified an antique alarm clock to turn the screw for me.

The idea of the sand back is to stabilize the camera you just set it in a bag of loosly packed sand. You want it to plop into the bag. With that on a rock the camera is far more stable than on any tripod costing less than several hundred dollars. Pushing the sand around in the bag can tilt the camera any way you want.

By tracking software I think you mean software that will align and then stack the 15 second images to remove the earth's rotation. I don't use a DSLR so am not up on that but it will be in the book. There's a DSLR forum at Cloudy Nights that could likely answer your question. Yahoo groups likely has one as well. DSLR takes RAW images (you don't want any lossy compression to be used or the artifacts will kill you) while a CCD like I use takes FITS files. They aren't compatible. I use pure FITS software. There are some out there that do both but I don't know them. A quck Google tells me Deep Sky Stacker will handle RAW images and is free. I've heard it is slow but at that price does it matter? Looks like it would do the job just fine.

The barn door platform requires a very solid and stable platform that is adjustable in both azimuth and elevation so you can align it precisely north and tilted to your latitude. I used the sandbag approach for that as well. Took a larger bag. My tracker was already built to my latitude as long as I imaged from one location. The base had a level and compass. I knew my magnetic offset. Since metal in a tripod head could ruin the compass pointing I use a sand bag. That was placed on a huge rock at my viewing site. I then pushed and proded the platform until it was level and the compass said I was true north. I made sure the spring was wound, engaged the "drive" to the screw with a one inch O ring stretched really tight and was ready to image. A ball camera mount allowed me to point the camera about anywhere. This is what I meant by building a lot of it in my early, poor days. You do a lot of designing. You have to know the needs of astronomy before you know what to design! No internet to help. Found the one and two hinge designs in an astronomy magazine over 50 years ago. I started with the one hinge but quickly outgrew it and came up with the 2 hinge alarm clock version It even had an adjustable 40mm 20x scope with cross hair eyepiece I could lock on a star before starting. You want one in the image field. I could check that to see if it was tracking properly. Later I devised a way to move the camera and guide scope to make corrections. Then i could use it up to 400mm focal length for 30 minutes. All for a few bucks and destorying an antique alarm clock that probably would have been worth a fortune in todays antique market. Or not.

Rick

galacticphoto
2010-Mar-10, 10:06 PM
While you're waiting for your copy of Covington's book (you did order one?), do a little Goggling, try "amateur astrophotography", or any of a number of related search phrases. You may also want to search with phrases including "camera lens". You'll be able to take a look at the type of equipment & software that various amateurs are using. You'll also see their photos (decide whether you like them or not).

Robert