Awesomelenny
Post Laureate
Reged: 05/02/04
Posts: 3787
Loc: Long: 81.42 W Lat: 41.21 N
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Hi,
Tell me, I have a Lumicon Ha filter and a Canon 10D camera. I know if I have the IR filter removed I could do Ha imaging with this camera. I have several questions though...
 will the exposures be significantly longer if the IR supplied on the camera in front of its chip?
Is it pretty much a waste of time to do this?
Should I just stick with my Lumicon OIII and do regular long exposures at say ISO 800?
If I can do Ha with my camera as it is, is there a way of capturing it in monochrome mode? I don't seem to find such an option in the manual.
Lotsa questions, huh?
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Len
WO Zenithstar 66
Takahashi FSQ 106N
A. Jaegers 6" f/5 RFT
A. Jaegers 6" f/10 refractor
Meade 8" f/10 LX200 SCT OTA
Atlas EQ-G Equatorial Mount
AP1200 GTO-CP3
A "Backyard Observatory"
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Rammysherriff
Carpal Tunnel
Reged: 03/26/04
Posts: 1967
Loc: Lancs, UK.
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Len,
with unmodified 350D it is possible to catch Ha but the only target I found worth doing was M42 because it is so bright. The Horsehead/Flame was beyond me. However with enough exposures of course it can be done but it seemed not worth it to me.
I don't think there is a monochrome mode as such on your camera or mine so you'll have to do this at post processing stage either by using astro software to extract a luminance image, or normal software usually lets you convert to a greyscale image.
M42 in Ha with 350D
Flame/Hrosehead in Ha with 350D
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Simon.
One man and his shed: http://s211.photobucket.com/albums/bb288/Astroshed/
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thelittleman
Vendor (Peter's Actions)
Reged: 05/21/05
Posts: 4079
Loc: Hampshire, UK
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Len - I think it can be done but as Simon says (lol) your exposures will have to be significantly longer to capture the amount as you would with a modded camera (obviously).
However, it would be an interesting experiment. It depends how long you think you can go without any trailing. I know if I have a decent guidestar I can exceed 10 minutes. I plan to image M42 some time this month and hopefully get a couple of hours worth of 10 minute exposures so it would be interesting to see how much stuff I got with that, without a filter and with an unmodded camera.
Simon - how long were your exposures? They don't look all that long, but if they were then you have basically just tried and tested my experiment...
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Clear Skies,
Peter
Photoshop Tutorials and Actions! New actions now added 
Preprocessing in Iris Tutorial
http://peter-morris.magix.net/
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Duncan Kitchin
Pooh-Bah
Reged: 12/16/04
Posts: 1278
Loc: Beaverton, OR, USA
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don't know, but I'm planning to try just as soon as I get a clear night  .
I have recently acquired (as in, late December...) an Astronomik H-alpha filter, which I'm planning to use with my unmodded 300D. I'll see what happens, and then look at modding my camera or buying a used 300/350D body used on eBay to mod or something...
My expectation is that I'm going to need much longer exposures to get anything, but that's ok; right now, from my back yard, the limit on my exposure time is sky fog by a factor of at least 5. I'm planning on, say, 15 minute exposures and I'll see what happens. Absent narrow band filtering, I can't do much more that 3 minutes.
Regards
Duncan
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QSI 583wsg / StarShoot Autoguider
Takahashi FSQ106ED
Astro-Physics Mach1
Celestron EdgeHD 11 / 0.7x reducer (new arrival)
150mm f/5 Newtonian, Baader MPCC
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Home Page
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Duncan Kitchin
Pooh-Bah
Reged: 12/16/04
Posts: 1278
Loc: Beaverton, OR, USA
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oh, and no, I don't think there's a way of capturing in monochrome mode. If there was, you probably wouldn't want it, because it would necessarily work by combining all of the pixel outputs in some way. As a result, you'd be getting what you want (the red channel) plus a contribution from the green and blue channels containing nothing but dark current (with associated noise).
Much better method is to capture in RAW, and separate the channels later. Then you can use the red layer by itself as a luminance channel.
Regards
Duncan
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QSI 583wsg / StarShoot Autoguider
Takahashi FSQ106ED
Astro-Physics Mach1
Celestron EdgeHD 11 / 0.7x reducer (new arrival)
150mm f/5 Newtonian, Baader MPCC
Stellarvue SV70ED
Home Page
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LLEEGE
True Blue
Reged: 03/03/05
Posts: 12767
Loc: Cloud-chester,NY
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You can set the camera to shoot in B/W. I don't know if its the same affect. ??? You can simulate different color filters in camera too....
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A wise man once said........nothing.
A good mount
A few good OTA's
A few good EP's
A decent camera
Crappy skies
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D_talley
Carpal Tunnel
Reged: 07/07/05
Posts: 1750
Loc: Richmond VA
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I currently use an unmodified Canon 10d with my scopes. You can image dso but must understand that objects that are very red will not show much. The attached image is one hour of the rosetta nebula. As you can see, the red is very dim. Several more hours are needed. The second photo, over process somewhat, is of the horsehead. Total of one hour exposure using the same unmodified Canon 10d. Better but not as good as a modified camera.
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Dwight
Antares 105mm F/15
TEC 140 APO #74
Meade LX200 14 OTA
Meade LX200 12 OTA
Intes Mk-67
AT12IN
Orion 12.5 DOB
SBIG ST2000xm
Celestron C8+
Celestron 102AZ
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Losmandy G8 Gemini
Telescope Drive Master TDM
Canon 350D full spectrum mod,Canon T2i full spectrum mod
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D_talley
Carpal Tunnel
Reged: 07/07/05
Posts: 1750
Loc: Richmond VA
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The horsehead for one hour
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Dwight
Antares 105mm F/15
TEC 140 APO #74
Meade LX200 14 OTA
Meade LX200 12 OTA
Intes Mk-67
AT12IN
Orion 12.5 DOB
SBIG ST2000xm
Celestron C8+
Celestron 102AZ
Losmandy G11 Gemini
Losmandy G8 Gemini
Telescope Drive Master TDM
Canon 350D full spectrum mod,Canon T2i full spectrum mod
Hyperstar
QHY5 Guider, ST-4 Guider, STV Guider
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Tonk
Postmaster
Reged: 08/19/04
Posts: 6100
Loc: Leeds, UK, 54N
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I'm a 10D owner and quickly learned that H alpha imaging wasn't worth the effort. There is plenty of stuff out there that is not H alpha. When my 10D gives up the ghost then I'll get a modded camera and try H alpha stuff. Meanwhile I hope to bag a load of stuff that would otherwise be passed over 
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Televue 85/TRF-2008 field flattener, Meade LX200 10", Manfrotto 055SSB tripod/410 geared head/AstroTrac TT320X-AG/056 3D head, GM-8/Gemini, 10 Micron 1000 HPS, Canon 40D (unmodded), Canon 450D (modded w/Astronomiks clip-ins - UV/IR, OWB), Coronado SM60/Lunt B1200/WO diagonal, Baader Herschel Wedge
Leeds Sky Clock Ripon Sky Clock
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jay52
Carpal Tunnel
Reged: 09/26/04
Posts: 2514
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I've often argued that if it takes 10 hours to collect Ha data with an unmodified DSLR, then how great would that image have been should you have taken that 10 hours on the full spectrum? You definitely need a camera sensitive to those wavelengths before you can take advantage of that type of imaging.
As for imaging in grayscale, the camera will still record the same data. It's not as if you've removed the color filter array on the chip when you switched to grayscale mode. Only 1/4 of the pixels will collect some Ha light, regardless of the mode you choose.
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jay
www.allaboutastro.com
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Duncan Kitchin
Pooh-Bah
Reged: 12/16/04
Posts: 1278
Loc: Beaverton, OR, USA
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Jay,
won't the duration of the subexposures make a difference? The problem being that, in very poor light pollution conditions, the image saturates in a couple of minutes for full spectrum, whereas with H-alpha, hopefully the subexposures will be several times the duration.
Regards
Duncan
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QSI 583wsg / StarShoot Autoguider
Takahashi FSQ106ED
Astro-Physics Mach1
Celestron EdgeHD 11 / 0.7x reducer (new arrival)
150mm f/5 Newtonian, Baader MPCC
Stellarvue SV70ED
Home Page
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Shadowalker
Apocaloptimist
Reged: 11/23/04
Posts: 10857
Loc: Carriere, Mississippi, USA
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Lenny,
My opinion is that answer is yes, but it will take about twice as much exposure time to get the same results. This is based on my experience with my unmodified 300D and Hutech modified 350D.
I've gotten good images of the Rosette with my unmodifed 300D at 10 minute subframes. Similar images were obtained with my Hutech modified 350D at 5 minute subframes.
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"The truth rarely gets in the way of a good story. ~ R. Woods
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Rammysherriff
Carpal Tunnel
Reged: 03/26/04
Posts: 1967
Loc: Lancs, UK.
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Len/Peter,
I think what we had there for the Horsehead was 5 minute exposures, and an hour's worth of them. My bottom line is the same as Tonk's.
That hour of imaging with a camera suited to the target would have been much better spent - ie if I had done the same with a mono ccd it would have been worth it but with an unmodded DSLR, there are better things to do!
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Simon.
One man and his shed: http://s211.photobucket.com/albums/bb288/Astroshed/
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Awesomelenny
Post Laureate
Reged: 05/02/04
Posts: 3787
Loc: Long: 81.42 W Lat: 41.21 N
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Wow guys, thanks a whole bunch. You all have put that in very good perspective. Now I have a much clearer understanding of what I will do. For now then, I will image with a IDAS LPS filter because of the bad light pollution I live under and at the same time, I will just watch around the markets to see if I can pick up a used Canon body for cheap and tinker with it by removing the IR glass and replacing it with a clear glass.
I just need to find out where in the world I read up on doing just that procedure. Somebody covered that in great detail along with pictures and all....Could be a really neat winter project to work on during those cloudy, snowy, rainy days which we have more than plenty of!
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Len
WO Zenithstar 66
Takahashi FSQ 106N
A. Jaegers 6" f/5 RFT
A. Jaegers 6" f/10 refractor
Meade 8" f/10 LX200 SCT OTA
Atlas EQ-G Equatorial Mount
AP1200 GTO-CP3
A "Backyard Observatory"
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Awesomelenny
Post Laureate
Reged: 05/02/04
Posts: 3787
Loc: Long: 81.42 W Lat: 41.21 N
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Rammysherriff,
I tinkered with your Ha image of the Horsehead. I used Images Plus to split the image into its RGB components and then just working with the red file, I tweaked the digital development to stretch the image somewhat and then applied sharpening to it. Then using NeatImage, I tweaked the roughness of the nebula to make this composite. I kinda like it...
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Len
WO Zenithstar 66
Takahashi FSQ 106N
A. Jaegers 6" f/5 RFT
A. Jaegers 6" f/10 refractor
Meade 8" f/10 LX200 SCT OTA
Atlas EQ-G Equatorial Mount
AP1200 GTO-CP3
A "Backyard Observatory"
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Rammysherriff
Carpal Tunnel
Reged: 03/26/04
Posts: 1967
Loc: Lancs, UK.
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Gary Honis' instructions for 300D and 350D filter removal:
web page
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Simon.
One man and his shed: http://s211.photobucket.com/albums/bb288/Astroshed/
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Awesomelenny
Post Laureate
Reged: 05/02/04
Posts: 3787
Loc: Long: 81.42 W Lat: 41.21 N
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Simon,
That's it! Great! I bookmarked it!
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Len
WO Zenithstar 66
Takahashi FSQ 106N
A. Jaegers 6" f/5 RFT
A. Jaegers 6" f/10 refractor
Meade 8" f/10 LX200 SCT OTA
Atlas EQ-G Equatorial Mount
AP1200 GTO-CP3
A "Backyard Observatory"
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jay52
Carpal Tunnel
Reged: 09/26/04
Posts: 2514
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Duncan:
Yeah, there's truth to that, assuming that LP really shortens your subexposure times. But in that case, I'm not sure anything is gonna help you. A certain amount of dark skies is kinda a prerequisite to this hobby, regardless of the camera. I'd almost rather fight the LP with the full power of the camera rather than try to syphon off a few photons over hours. When a camera has sub 1% PE at 656.3nm, I just think your time is better spent another way. Now, modify that camera for a good 5% to 10% PE, then we can accomplish something.
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jay
www.allaboutastro.com
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