ICEINSPACE
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06-04-2012, 11:57 PM
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Registered User
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Join Date: Jan 2005
Location: Newcastle, NSW, Australia
Posts: 4,112
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What would really interest me is a MONOCHROME sensor equipped Canon camera, I.E. a bog standard EOS DSLR without the colour bayer filter and with no IR cut filter at all. In theory it should be no dearer than a normal camera but its wishful thinking such a camera would be made I think.
Seeing as how the EOS sensors work as well as they do at room temeprature, a monochrome 18 MP cooled EOS camera would blow every dedicated astro camera out of the water as far as dark current noise went.
Then I once used the GRAS (now Itelescope) online scopes, the raw light frames still had some dark current noise, which was easy to subtract as they also sent me a master dark from darks at the same temperature. However when I borrowed Houghys cooled DSLR the noise, or rather lack of it even on the raw light frames was mind boggling. The only thing that stops them from cornering the astro camera market is they are colour not monochrome chips.
Look at what cooling an EOS sensor does. That, in monochrome with accurate temperature control would be absolutely brilliant. You could do 1 hour subs with hardly any noise. Remember as a guide the Central DS 600d "only" cools to 28 deg below ambient yet returns stunningly dark darks that have to be heavily stretched to show noise.
Scott
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07-04-2012, 01:28 AM
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Old Man Yells at Cloud
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Join Date: Jan 2007
Location: Rockingham WA
Posts: 3,435
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Quote:
Originally Posted by rogerg
Locally, PRA have announced you can pre-order it.
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Cheers Roger, looks like I might have to lift my decade long boycott of PRA.
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07-04-2012, 12:39 PM
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Canon collector
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Join Date: Oct 2005
Location: Taylors Lakes Melb
Posts: 1,965
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Dohh!! I only just ordered the 7D last week and had no idea they where releasing this Astro dedicated 60Da but think it's great that they have considered this side of Photography.
Looking forward to reading the reviews and am wondering if it is more than just removing the filter.
Cheers Daniel.
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07-04-2012, 02:05 PM
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Registered User
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Join Date: Jan 2009
Location: Melbourne
Posts: 203
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Quote:
Originally Posted by danielsun
Dohh!! I only just ordered the 7D last week and had no idea they where releasing this Astro dedicated 60Da but think it's great that they have considered this side of Photography.
Looking forward to reading the reviews and am wondering if it is more than just removing the filter.
Cheers Daniel.
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Hi Daniel
If you only just ordered it, you should be able to change the order without any penalty.
Cheers Mark
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07-04-2012, 02:12 PM
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The devil's advocate
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Join Date: Jul 2011
Posts: 816
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Quote:
Originally Posted by tornado33
What would really interest me is a MONOCHROME sensor equipped Canon camera, I.E. a bog standard EOS DSLR without the colour bayer filter and with no IR cut filter at all. In theory it should be no dearer than a normal camera but its wishful thinking such a camera would be made I think.
Seeing as how the EOS sensors work as well as they do at room temeprature, a monochrome 18 MP cooled EOS camera would blow every dedicated astro camera out of the water as far as dark current noise went.
Then I once used the GRAS (now Itelescope) online scopes, the raw light frames still had some dark current noise, which was easy to subtract as they also sent me a master dark from darks at the same temperature. However when I borrowed Houghys cooled DSLR the noise, or rather lack of it even on the raw light frames was mind boggling. The only thing that stops them from cornering the astro camera market is they are colour not monochrome chips.
Look at what cooling an EOS sensor does. That, in monochrome with accurate temperature control would be absolutely brilliant. You could do 1 hour subs with hardly any noise. Remember as a guide the Central DS 600d "only" cools to 28 deg below ambient yet returns stunningly dark darks that have to be heavily stretched to show noise.
Scott
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Will say the tests of this gens sensors are mind blowing, I think next gen even without cooling EOS cameras will give dedicated astro cameras one hell of a run while even un-cooled. Technology is catching up and it won't be long before it gets hard to justify the pricing of of astro cams. With hacked firmware like magic lantern http://http://magiclantern.wikia.com/wiki/Magic_Lantern_Firmware_Wiki , DIY filter modding and cooling its really putting out of reach dedicated astro cams into all peoples hands and its great
I've just done a 1100D filter mod myself and can't wait to play with some cooling Magic lantern is currently in development for 1100D support which will crack the iso limits right open on this baby Hmm will be waiting to see if canon has any firmware changes on the 60Da myself, though i think this will be doubtful, it could open up some a ton of firmware in the AP world. BTW that link to pre-modded cooled cameras is great bud
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07-04-2012, 02:42 PM
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Lost in Namibia
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Join Date: Aug 2005
Location: Albury NSW
Posts: 3,133
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Getting excited
Cheers Petra d.
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07-04-2012, 03:07 PM
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Tech Guru
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Join Date: Dec 2005
Location: Sydney
Posts: 2,846
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Should have looked in this forum first! From my read its an Astronomik IR filter. I've send many letters to Canon research for DSLRs over the past few years, refering them to Badder, Hutech and Astronomik IR filters. Slightly surprised they went the Astronomik route, I'll see if I can find out why.
The other idea I suggested was a user specified Liveview and Remote Live view settings for 1/10 sec up to 30 seconds. I think it was software locked to 3 frames per seconds, but there was no reason why a user couldn't verfiy this for hobby shots that required more signal from loner exposures. Wonder if Canon handled this?
Meanwhile just delighted this model has turned up!
Last edited by g__day; 07-04-2012 at 03:32 PM.
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07-04-2012, 03:51 PM
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Canon collector
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Join Date: Oct 2005
Location: Taylors Lakes Melb
Posts: 1,965
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Quote:
Originally Posted by trek1701
Hi Daniel
If you only just ordered it, you should be able to change the order without any penalty.
Cheers Mark
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Bought it on the net. Checked with them on Thursday, payment has gone through and it's well on it's way but that's ok, still very happy with the features of the 7D . Will wait and checkout the reviews of the 60Da and may end up also getting one down the track.
Cheers Daniel.
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07-04-2012, 05:00 PM
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Country living & viewing
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Join Date: Mar 2006
Location: Armidale
Posts: 2,790
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Quote:
Originally Posted by Octane
Things have come a long way since the 20Da in terms of sensor and high ISO characteristics.
Where you would be loathe to push past ISO-800 on the 40D, you can comfortably image at ISO-1600 on this newer camera, halving your exposure time.
In today's crappy weather, this is a windfall.
H
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For astro imaging, why does a high ISO make any difference?
All it does is change the in camera amplification ie the gain of the CCD. This potentially reduces the dynamic range of your image. All astro photos should really be taken as RAW and amplified if needed afterwards anyway.
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07-04-2012, 05:06 PM
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Certified Village Idiot
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Join Date: Jul 2006
Location: Mexico city (Melb), Australia
Posts: 2,341
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Jeezz...maybe a cooled spectrum modded camera from central DS is a better option.... 1100D or 600D.
Of course this in the price territory of an KAF 8300 OSC...although more pixels.
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07-04-2012, 05:18 PM
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The devil's advocate
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Join Date: Jul 2011
Posts: 816
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Quote:
Originally Posted by g__day
Should have looked in this forum first! From my read its an Astronomik IR filter. I've send many letters to Canon research for DSLRs over the past few years, refering them to Badder, Hutech and Astronomik IR filters. Slightly surprised they went the Astronomik route, I'll see if I can find out why.
The other idea I suggested was a user specified Liveview and Remote Live view settings for 1/10 sec up to 30 seconds. I think it was software locked to 3 frames per seconds, but there was no reason why a user couldn't verfiy this for hobby shots that required more signal from loner exposures. Wonder if Canon handled this?
Meanwhile just delighted this model has turned up!
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Well there own in house Low pass filter does a better job then any IR cut in the digi 4's from my reading and first hand experience. It wouldn't surprise me if there just using a astronomik MC clear, as the LP is an IR cut and gives a better spectrum then any of these filters. If they have gone for astronomik it will be for price and being able to fill there demand. Anyhow this if from what I know and understand, I could be total wrong
Umm liveview vai EOS utils works fine here for my 1100D's on whatever is set it for, maybe you should try updating EOS utils from canon. From the camera try updating the firmware from canon, if not flash with magic lantern which I would have done when i got the thing, canons firmware is n00b locked
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07-04-2012, 10:37 PM
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Tech Guru
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Join Date: Dec 2005
Location: Sydney
Posts: 2,846
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2Stroke - I don't have any Canon's with LiveView, I merely fired some questions to Canon Research (CiSRA) to ask if LiveView frame per second was alterable to make really long duration shots in low light - and was told no, it didn't go below 3 frames per second (user configurable). I explained how for astrophotography this option might be a boon when framing shots.
Are you saying there are utilities (Canon or 3rd party) that will allow you to determine how long each frame in Remote LiveView may be (and /or to up their gain / gamma)?
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07-04-2012, 11:00 PM
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Registered User
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Join Date: Feb 2005
Location: Brisbane
Posts: 942
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Quote:
Originally Posted by tornado33
What would really interest me is a MONOCHROME sensor equipped Canon camera, I.E. a bog standard EOS DSLR without the colour bayer filter and with no IR cut filter at all. In theory it should be no dearer than a normal camera but its wishful thinking such a camera would be made I think.
Seeing as how the EOS sensors work as well as they do at room temeprature, a monochrome 18 MP cooled EOS camera would blow every dedicated astro camera out of the water as far as dark current noise went.
Then I once used the GRAS (now Itelescope) online scopes, the raw light frames still had some dark current noise, which was easy to subtract as they also sent me a master dark from darks at the same temperature. However when I borrowed Houghys cooled DSLR the noise, or rather lack of it even on the raw light frames was mind boggling. The only thing that stops them from cornering the astro camera market is they are colour not monochrome chips.
Look at what cooling an EOS sensor does. That, in monochrome with accurate temperature control would be absolutely brilliant. You could do 1 hour subs with hardly any noise. Remember as a guide the Central DS 600d "only" cools to 28 deg below ambient yet returns stunningly dark darks that have to be heavily stretched to show noise.
Scott
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Hi Scott,
A monochrome option already exists - there are a number of Kodak 8300 CCD cameras available and now the Sony 694 Exview II sensors. I have seen some of these go for very good prices here on IIS.
Terry
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08-04-2012, 02:38 AM
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The devil's advocate
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Join Date: Jul 2011
Posts: 816
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Quote:
Originally Posted by g__day
2Stroke - I don't have any Canon's with LiveView, I merely fired some questions to Canon Research (CiSRA) to ask if LiveView frame per second was alterable to make really long duration shots in low light - and was told no, it didn't go below 3 frames per second (user configurable). I explained how for astrophotography this option might be a boon when framing shots.
Are you saying there are utilities (Canon or 3rd party) that will allow you to determine how long each frame in Remote LiveView may be (and /or to up their gain / gamma)?
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hmm think your right on that one just tinkering now and exposure is doing squat :/ Lol i've never noticed , ill keep playing when i get a chance. I just up the iso to 400 when in live veiw.
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08-04-2012, 03:10 AM
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Registered User
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Join Date: Jun 2010
Posts: 438
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Quote:
Originally Posted by Terry B
For astro imaging, why does a high ISO make any difference?
All it does is change the in camera amplification ie the gain of the CCD. This potentially reduces the dynamic range of your image. All astro photos should really be taken as RAW and amplified if needed afterwards anyway.
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The Signal to Noise ratio improves as you increase the ISO. This is because the sensor read noise is not amplified as the signal is.
So as long as the dynamic range is enough you should shoot at the highest possible ISO for a given exposure time.
For most DSLRs this stops making sense beyond ISO1600 but up to 1600 the higher the better.
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08-04-2012, 09:13 AM
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Country living & viewing
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Join Date: Mar 2006
Location: Armidale
Posts: 2,790
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Quote:
Originally Posted by luigi
The Signal to Noise ratio improves as you increase the ISO. This is because the sensor read noise is not amplified as the signal is.
So as long as the dynamic range is enough you should shoot at the highest possible ISO for a given exposure time.
For most DSLRs this stops making sense beyond ISO1600 but up to 1600 the higher the better.
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I would have thought that astro photos all have a very high dynamic range. The difference in brightness of stars compared to DSO objects is very high. As long as you are happy losing almost all of the colour data for stars then I suppose this is ok.
I'm also curious about the read noise.
When is the gain (or ISP amplification) applied?
I thought that the order was that each line of the ccd is read then the gain is applied. This would mean that the read noise is also affected by the gain.
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08-04-2012, 01:28 PM
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Registered User
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Join Date: Jan 2009
Location: Melbourne
Posts: 203
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I’ve been told that you should use Liveview at least as possible (even though you need it to achieve actuate focus) because it increases noise, is this info correct???
Cheers Mark
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08-04-2012, 02:27 PM
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Registered User
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Join Date: Jun 2010
Posts: 438
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Quote:
Originally Posted by Terry B
I would have thought that astro photos all have a very high dynamic range. The difference in brightness of stars compared to DSO objects is very high. As long as you are happy losing almost all of the colour data for stars then I suppose this is ok.
I'm also curious about the read noise.
When is the gain (or ISP amplification) applied?
I thought that the order was that each line of the ccd is read then the gain is applied. This would mean that the read noise is also affected by the gain.
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The DSLRs use CMOS not CCD
You have a wonderful explanation here:
http://theory.uchicago.edu/~ejm/pix/...ise/#readnoise
Quote:
Originally Posted by trek1701
I’ve been told that you should use Liveview at least as possible (even though you need it to achieve actuate focus) because it increases noise, is this info correct???
Cheers Mark
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This is true, live-view increases thermal noise. So I use it to focus, frame and then turn it off for the rest of the night.
After about 1 minute of live-view you need 8 minutes off for the sensor to be back at the temperature it started.
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08-04-2012, 02:32 PM
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Registered User
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Join Date: Jan 2009
Location: Glenhaven
Posts: 4,161
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Quote:
Originally Posted by luigi
The DSLRs use CMOS not CCD
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Not quite true Luigi. For example my Sony has a CCD, and other manufacturers use the same Sony chip.
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08-04-2012, 08:18 PM
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Registered User
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Join Date: Jun 2010
Posts: 438
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Quote:
Originally Posted by mithrandir
Not quite true Luigi. For example my Sony has a CCD, and other manufacturers use the same Sony chip.
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Yup but we are talking about the 60d here.
My stellar was not very writing but the sensor CMOS 60da is a
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