How to Image on a shoestring budget

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How to Image on a shoestring budget
Posted by johnjohnson on Friday, June 19, 2009 7:46 PM

 

I have been imaging now for a while with a 120mm Orion EON ED refractor. I had an old Orion 6" ST F5 750mm reflector sitting in the corner of the garage. Knowing that many reflectors won't come to focus with DSLR cameras I had not given it a try. Just out of curiosity though, I decided to give it a shot one night. I noticed that the upper part of the focuser could be removed and a T-Ring could be screwed directly on to the adapter on the silver part of the focuser tube.

 

This is another view of the whole rig. This is the mount I used for imaging here on this thread and is also my quick grab and go mount. I used an EQ 5 clone. I will modify it for guiding later in this thread.

The night I tested the rig to see if it would come to focus the Moon was out and a little past half. I decided to use it as a target. Low and behold the thing actually came to focus with room to spare. It makes a great wide field imaging scope at 750mm. The Moon image came out sharp and well focused with no chromatic aberration. I also shot the Dumb Bell nebula with it but can't seem to find the image any more. Here is the Moon shot though. It has been cropped as I could probably get 3 Moons in the field of view.

I picked this scope up used for $150 for a grab and go. It does do a fine job for what it is. The only draw back is with the upper part of the focuser removed, you can't use a barlow to up the magnification (Focal Length). In this configuration it can only be used at F5 750mm. I don't think there is enough in travel left on the focuser to use a reducer. Those on a tight imaging budget might consider looking for one of these used.

JJ

 

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by galactic_photog on Saturday, June 20, 2009 6:46 PM

johnjohnson
Low and behold the thing actually came to focus with room to spare.

Newts, at least properly configured newts, make great imaging scopes. I've been using a newt (originally an 8", followed by a 10") for galaxy imaging. The 10" newt focus point is 5-6" out of the tube, no problem for the mono ccd plus filter wheel (with the Baader coma corrector inside the focuser.

A primary mirror move (and upsize of the secondary) would easily allow for a Wynn reducer/corrector to be used in place of the simple coma corrector (the approach used on the expensive ASA and Orion Optics f/2.8 to f/3.8 newt astrographs). Don't discount the newt, it can work well for photography.

Robert

SPX250 or Mewlon250 on MI-250 TMB92SS or ED80 on CGE H9+FLI wheel or Skynyx2-0+Truetech wheel Astronomiks filters in both wheels 10 X 42 IS binos for visual
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Posted by tkerr on Sunday, June 21, 2009 10:06 AM
That's interesting to know that you can thread the draw tube directly to the T-Ring. Essentially it's the same as using a lower profile focuser with a zero profile T-Adapter. Certainly a lot easier than modifying the tube to move the primary mirror.

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Equipment: Orion XT10 Classic, Celestron C6 R-GT (CG5 GT mount), C80ED Canon EOS 350D, Canon EOS 50D, Meade DSI II Color CCD, Phillips SPC900NC

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Posted by johnjohnson on Wednesday, June 24, 2009 10:52 PM

tkerr,

Yes the upper inch and a half of the focuser draw tube simply unscrews and the T-ring can be threaded directly to whats left. I also noticed that the secondary is quite large. It's to bad the focuser is only a 1.25 inch model but that is common for apertures less than 8". 

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Thursday, June 25, 2009 6:09 AM

I got a chance to try out the 6" reflector on a DSO. This was taken at 4:00 am so dawn was coming and beginning to wash out the sky.This was 16 images of 10 seconds each at ISO 1600. Canon EOS XSi at prime focus. EQ 5 ( Sky View Pro clone) mount unguided. I used the 10 second self timer to eliminate the shakes. I just wanted to see if the reflector would focus easily and take faily good images. There was some vignetting so I croped it off. Processed with DSS, then GIMP, then PS elements.

This is what the images looked like before processing. I was surprized how the main images came out.

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Thursday, June 25, 2009 6:56 AM

I found the image of the Dumb Bell M 27 nebula that I took with this scope. It was on the EQ 5 clone mount unguided. I don't recall the spec's for ISO or number of images stacked as it was a while back. The stars are a little elongated but a perfect image was not my goal that night. I did not do a very good polar alignment either so the stars are probably elongated in Declination. I just wanted to see how well it would wide field image.

 

JJ

 

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Sunday, June 28, 2009 1:50 PM

Last night 6/ 27/09 I had another excellent chance to try out this rig. I imaged M56. This is 256 images of 20 seconds each. This was done from down town Sioux Falls SD. Images stacked using DSS, and processed with Gimp and PS elements. I am real pleased with it as I modified my Apogee EQ 5 clone mount with dual axis drives to have an ST4 input  and guided it with an Orion SSAG. Not to bad for one of the crummiest mounts in history! The mount cost $150 brand new!

 

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Saturday, July 04, 2009 1:53 PM

Modifying an Orion dual axis hand controller for an ST4 guide port. This is a real easy mod to do and guides very well at short focal lengths. The hand control has to be used in the 2X sidereal mode for guiding. The mod was described on the Shoe String Astronomy web site. This mod can apply for the EQ 5 mounts. using dual axis controllers. The clone mounts can be found on Ebay by typing in the following search description.

CG-5 type Dual Motor Equatorial Telescope EQ Mount

http://www.store.shoestringastronomy.com/eq_mod.pdf

 

This is the modified hand control and all parts were bought at Ace hardware. A six line phone line and coupler. Make sure to use the end that gives the straight through connections to keep the color coding correct. This works perfect with the Orion Star Shoot Auto guider and it's cable.

 

JJ

 

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Thursday, December 03, 2009 8:32 PM

Got another chance to test out this rig. Shot from backyard in town. 60 images of 45 seconds each. Canon XSi at prime focus, ISO 800. Guided with SSAG and PHD through a 60mm Celestron refractor. 6" Orion short tube reflector. No flats, No darks. processing was DSS, Gimp. PS.

 

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Thursday, December 03, 2009 8:50 PM

Back in June I took an image of the Sun and spot group 1019. Single shot With XSi. Image cropped to show group. processed with PS elements 6. False color added to enhance spots.

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by Kevin Bozard on Thursday, December 03, 2009 10:30 PM

 pretty cool shots JJ. I've always wanted to use one of my reflectors with my DSLR, but focusing remains a problem. I even purchased a zero profile adapter, which didn't help.  I thought about maybe adding a low profile focuser, but didn't want to spend the money when there's a chance it won't help either. So I just keep using the refractors for imaging. With the skies the way they've been this year, there hasn't been much imaging going on anyway!

"Good friends are like stars, you don't always see them, but you know they're always there."

kevinbozard.com

Equipment (so far): C6R-GT, C 80ED, Orion XT8, Orion XT10, Coronado PST, Zhumell 20x80 Binos

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Posted by johnjohnson on Friday, December 04, 2009 4:22 AM

Kevin

Have you tried Barlowing your reflector? When imaging with my refractor, which has graduations on the draw tube, I all ways right down the settings for the different optics. I found that at prime focus and barlowed, there was a difference of 3 cm of out travel provided by the barlow. This could quite make the difference you need to focus.

I have done FOV indicators in The Sky 6 and my Canon XSi has a very equivalent FOV to a 27mm Panoptic. I therefore use the Pan to center and adjust my field. That is the equivalent to a low power EP. We know that Barlows extend the eye relief of low power EPs, so it should do the same for the camera. I have not tested this on a reflector but it could be true.

JJ  

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnm on Friday, December 04, 2009 8:16 AM

 JJ,

You didn't need the Shoestring interface box with the Orion SSAG, right? The SSAG can conect directly to the RG cable from the hand controler and to the computer USB?

I want to do that to a Vixen DD1 and Shoestring shows a picture of the solder points for that controller.

Equipment: Some telescopes 

WRSO

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Posted by johnjohnson on Friday, December 04, 2009 11:40 AM

 Johnm

That's correct. The SSAG cable hooks Directly up to the new port just as if you were connecting it to the guide port on any other mount. You will have to set your hand box directional slew speed to it's lowest value, in my case 2X. I found it to be a very easy mod. You will have to work on your mount to get as much backlash out of it as you can.The motors themselves have plenty of built in backlash! I would not want to image with this mount at much over F5 or 750mm due to the backlash.

Good luck on you mod.

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnm on Friday, December 04, 2009 12:21 PM

 That's what I thought. One of the reasons I got the SSAG was because of the opto-electronic circuit. My split ring uses a Losmandy G11 controller and they need the SBIG relay or an isolated circuit in the guide camera. I'm using Vixen MT1 motors on a CG-5 mount because it has a little more capacity than my old Vixen GP, be nice to hook up an auto guider to it.

Equipment: Some telescopes 

WRSO

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Posted by johnjohnson on Saturday, December 05, 2009 1:49 PM

Here I really put the scope and mount to the test. I wanted to see if I could image a very faint object from town with moderate light pollution. I did not use any filters. I chose NGC 6960 or the West side of the Veil nebula. Would a 6" reflector do any thing from town? Would the clone mount guide good enough to get any resolution? Well it sure surprised me. This is a cropped image to cut out the vignetting. 120 images of 30 seconds each. Canon XSi ISO 800. Guided with SSAG through 60mm Celestron refractor and PHD. Processed with DSS, Gimp, and PS6.

JJ 

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Monday, March 15, 2010 5:04 PM

Latest upgrade to this system was to replace the tripod with a steadier mount. This kinda happened by accident. One of our club members built a portable pier for his CG5 GT and didn't need the tripod anymore. It has the 2" diameter stainless steel legs and a leg spreader. My old tripod had no spreader and was shaky especially in the torsional axis. This was a direct bolt on exchange to my clone mount. I traded him and old gateway laptop for it. It is solid as a rock now and I expect to be able to guide even better now. Cost = $0.0 as the gateway laptop had been moth balled anyway.

Old tripod in front of new one.

 

The rig now.

 

JJ 

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Monday, March 15, 2010 6:26 PM

I took the wide field image of M56 and zoomed way in to check the old mount and tripod's rigidity. The SSAG did a good job of guiding as the stars are not trailed but they are not quite perfectly round. I lay blame on that to the old tripod and a bit of a breeze on the night I imaged M56. I will have to do another zoom on a star field with the new tripod and see if it helps or if it is that the SSAG just can't guide this chepo mount as good as could be.

Wide field full frame.

 Zoom and cropped.

 

Still not too bad for a chepo mount on flimsy legs and guiding at 2X sidereal rate!

JJ 

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Friday, April 01, 2011 9:58 AM

Well after about a year in hiatus from astro imaging due to a home burglary, I just purchased a new Canon T1i. I gave it a quick and dirty first light on this telescope system because of it's easy set up and convenience. The Moon was waxing gibbous and seeing was a 6.5 out of 10. I did a very rough polar alignment. I did not have the guiding scope set up and did not have my lap top either. This is a single 30 second shot at  ISO 800, using the 10 second self timer and mirror locked up. This scope mount and camera combination still surprises me as the whole package is less than $1000.

 

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by tkerr on Friday, April 01, 2011 10:18 AM

Nice Thumbs Up

Just imagine what a whole bunch of those 30 second exposure would do.  Or with Guiding if you pushed the exposure to 45 or 60 seconds each.  

I've been seeing some great images taken with that camera.  
If you're interested in participating in forum discussion with people that also use Canon EOS DSLR check out the Photography On The Net Forums.  You'll probably recognize a few names there.

Have A Nice ...
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Equipment: Orion XT10 Classic, Celestron C6 R-GT (CG5 GT mount), C80ED Canon EOS 350D, Canon EOS 50D, Meade DSI II Color CCD, Phillips SPC900NC

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Posted by shstar56 on Saturday, April 23, 2011 12:09 PM

Do you do any deep sky imaging on a shoestring budget?  I've given myself a few years to collect all I need to do this, and hopefully, I'll be able to afford my hobby then.  Can you suggest any where online where I can scout around for used equipment?

Thanks!   NICE shot of the moon, BTW.

DONNA

Nextar SE 8

Neximage

Eye Pieces: Celstron PLOSSL 2X barlow, 6 8 13 17 25 32 Orion 20mm Illuminated Centering Eyepiece

 Meade F 6.3 focal reducer

Filters O-III moon 21 56 58 80A 12 25 

Meade DSI II Color Imager

 

 


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Posted by johnjohnson on Saturday, April 23, 2011 2:53 PM

Yes I set that system up about once a month now that the snow is gone and temps are rising. Look for more images in the future.

A good place to look for used equipment is on Cloudy Nights Classifieds.

Cloudy Nights Classifieds

Good luck in your searches.

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Monday, April 25, 2011 1:22 PM

On Easter Sunday 4/24/11  I got a chance to do some solar imaging with this setup. I used a Canon A495 point and shoot set to auto and used the 10 second timer to reduce the shakes. After viewing spot group 1195 and 1193 I began my imaging session.

This first shot was taken of the entire solar orb and spot group 1196 is discernible in the image but I did not notice it visually. Image was taken A Focal through a 26mm Orion Highlight plossel EP with my PVC adapter. See this link : A Focal Point & Shoot

I used the Badder solar filter for my 6". The original hue was bluish but I used PS elements to ghange the hue to a more pleasing color.

This next shot was of spot group 1195 up close. I still used the 26mm Plossel but added my 2X Orion Shorty plus barlow, and set the cameras zoom to max. Once again I changed the hue to a more natural color. Focus may have been a bit soft as the camera does this itself. Due to the heat waves and atmospheric scintillation the camera was chasing focus quite a bit.

I also used a modified Logitech C300 web cam to image SOL. After taking several AVI files and stacking them with Registacks I was not pleased with the out comes. The skies were just not steady enough for stacking and the images looked very averaged and soft.

 

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by BAZ PEARCE on Tuesday, April 26, 2011 3:31 PM

I managed to get this image done of the same region on Sunday 24/04/11 using the scp880nc webcam that arrived Saturday.

Prime focus, with Baader full aperture homebuilt filter, 1.25" medium reach adapter with barlow X2, and moon filter, which made focussing easier. Registax used to stack 40 seconds or so of video, using layering to sharpen the image, then lowering saturation and lightness to improve the contrast. Recorded in mono since its only white on black. 

Not too bad for my 1st go at photography. Seeing was clear but it was breezy enough to affect the atmosphere, but not to shake the scope about on my balcony.

51729495

Baz.

PS. Hope this link works ok. first time i've attempted this too. Whistling

British weather don't half suck!

Celestron Astromaster 130 EQ, 80mm utilityscope.

6mm K, Celestron 10mm, 15mm OMNI, 12, 20, 25mm Meade MA EPs. APO 3 speed Barlow lens.

Solar, Light pollution, 11, 12, 23A ,82A Baader ir/uv cut filters.

Philips SPC880NC webam with 1.25" adapter, 0.6 reducer 10X50, 12X50 (BAK-4) sports bino

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Posted by tower3 on Tuesday, April 26, 2011 4:44 PM

Good for you! I wouldn't have thought it could be done with that scope and tripod, You have much more patience than me.

EASY DUDE, THERE WILL BE ANOTHER WAVE

From San Diego, Zhumell Z10 (Bubba is for all around observing)Telrad, Vixen VMC110L on a Porta Mount II,  Bushnell 10x50 (for beach) Garrett 10x50 classics (for Sylvia), Zhumell 80x20 on their Pro tripod(cuz they were cheap and sylvia digs 'em),  1.75 readers (so I can find the other stuff)

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Posted by shstar56 on Thursday, April 28, 2011 8:25 AM

Hey JJ,

I just saw this post....what set up is it you mention that cost less than 1K?

DONNA

Nextar SE 8

Neximage

Eye Pieces: Celstron PLOSSL 2X barlow, 6 8 13 17 25 32 Orion 20mm Illuminated Centering Eyepiece

 Meade F 6.3 focal reducer

Filters O-III moon 21 56 58 80A 12 25 

Meade DSI II Color Imager

 

 


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Posted by johnjohnson on Thursday, April 28, 2011 8:55 AM

 

Donna

That would be the telescope and mount that this thread is all about. Got to the very beginning of this thread for images and explanations of the steps I took to evolve this economical system. It is in no way the greatest system for AP but it can get a person out under the stars and taking images. The major expense in this system is going to be the DSLR and laptop. The telescope / mount/ guide system cost right about $1K buying and using used equipment.

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by johnjohnson on Thursday, April 28, 2011 9:10 AM

BAZ PEARCE

Not too bad for my 1st go at photography.

BAZ

Indeed not. Very good first attempt. Isn't it great the rewards of imaging for one's self. To keep with the subject of this thread, how much do you think you have invested in your imaging system. Explain the system setup, equipment used and the camera settings and any processing involved. This is to help others who are first timers and to promote the fact that you don't have to spend alot of money to have some imaging fun and descent results.

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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Posted by Poppa Chris on Thursday, April 28, 2011 1:51 PM

The solar shots are pretty darned good.  I'm suitably impressed.

I have been thinking of getting a solar filter for my 11" SCT but they are pretty pricey at that size.  So I also have the idea of getting a smaller one that would fit the 55mm-250mm Zoom lens that came with my DSLR.  Any comments on how this would work out?  I can't think of a reason as to why it wouldn't work, but I'm not sure of what the outcome would be.  Or if it would be worth the effort.

 

 

---Poppa Chris---

Denham Springs, Louisiana USA

"Second star to the right - Then straight on until morning!" - Peter Pan

Celestron CPC1100GPS (XLT) - 279mm aperature, 2800mm Focal length. (f10) Celestron Ultima LX (70deg AFOV) Eyepieces 32mm thru 5mm, Canon EOS Rebel T2i DSLR, Backyard EOS imaging software, Orion Star Shoot Planetary Imager IV, Celestron Skymaster 15x70 binoculars

 

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Posted by johnjohnson on Thursday, April 28, 2011 3:20 PM

Poppa

I just did a FOV indicator in the Sky 6 and it looks like with the 250mm zoomed all the way out, you will get a image that covers over half the chip of the T2i. I used the Chip size of 22.3 X 14.9mm and 5184 X 3456 pixels to determine a pixel size of 4.3 X 4.3 microns. Then using the lens data of F5.6 at 250mm = aperture of 44.6mm. A filter for it would certainly be far less expensive than the 11". I think it should be worth the effort. At 18MP a person can also crop the image down to 6 or 8MP and still have a very detailed image. Just my opinion but I think it would work just fine.

Another way to check to see how the Sun will fit in the FOV is to go out on a full Moon night and zoom on it with the camera and 250mm lens. The Sun and Moon cover the same arc minutes of sky. If the Moon frames well at 250mm then the Sun will also.

JJ

20" F5 Obsession, OMI mirror .987 Strehl. 10" F4.7 reflector. 6" F5 ST reflector. 120mm F7.5 EON. 80mm F11.3 guide scope. SkyWatcher EQ-6 Hyper Tuned.   Flicker Astro Site   More Astro Images

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