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19-04-2010, 07:00 PM
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Registered User
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Join Date: Aug 2005
Location: Hahndorf, South Australia
Posts: 4,302
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Phil - thanks for addressing many of my (unwritten!) concerns in your 2 posts, specifically those issues associated with mounting lenses on the CCD camera.
I hadn't assumed there would be any great difficulty in getting an adapter for my 2 Canon EF L lenses, but I was worried about the focussing distance with the same QHY9/CFW setup that you have (this is the mono setup I had been considering)
Also, I image solely from my backyard so transport convenience isn't an issue and I suppose by even considering this route from DSLR to CCD, I am chasing the best possible results from my imaging!
So my question is...Is the 16bit dynamic range afforded by CCDs noticeably superior to the 14bit Cooled DSLRs in widefield imaging?
Cheers
Doug
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19-04-2010, 07:22 PM
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Registered User
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Join Date: Jan 2007
Location: Mount Glasgow (central Vic)
Posts: 1,091
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Quote:
Originally Posted by dugnsuz
Phil - thanks for addressing many of my (unwritten!) concerns in your 2 posts, specifically those issues associated with mounting lenses on the CCD camera.
I hadn't assumed there would be any great difficulty in getting an adapter for my 2 Canon EF L lenses, but I was worried about the focussing distance with the same QHY9/CFW setup that you have (this is the mono setup I had been considering)
Also, I image solely from my backyard so transport convenience isn't an issue and I suppose by even considering this route from DSLR to CCD, I am chasing the best possible results from my imaging!
So my question is...Is the 16bit dynamic range afforded by CCDs noticeably superior to the 14bit Cooled DSLRs in widefield imaging?
Cheers
Doug
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The M54 thread on the QHY filter wheel is not that common.. I certainly could not find an adaptor to do the job and had to get one custom made (as well as reducing the thickness of the camera-filter wheel connector).
I'm not sure that 16 or 14 bits is the thing to worry about - a lot of other factors are more important. I've got some test shots that give a direct comparison.. will try to finish processing and post soon..
After a few months with both, I'm very impressed with the performance of the cooled DSLR for widefield work. But the h-alpha shots with the QHY9 are also appealing..
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19-04-2010, 07:38 PM
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Registered User
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Join Date: Aug 2005
Location: Hahndorf, South Australia
Posts: 4,302
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Quote:
Originally Posted by philiphart
The M54 thread on the QHY filter wheel is not that common.. I certainly could not find an adaptor to do the job and had to get one custom made (as well as reducing the thickness of the camera-filter wheel connector).
I'm not sure that 16 or 14 bits is the thing to worry about - a lot of other factors are more important. I've got some test shots that give a direct comparison.. will try to finish processing and post soon..
After a few months with both, I'm very impressed with the performance of the cooled DSLR for widefield work. But the h-alpha shots with the QHY9 are also appealing..
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I've been using Astronomik 12nm Ha and OIII EOS clip-in filters with the 40D recently and have blended their results with my RGB's or made synthetic RGBs - I'm quite happy with the results. Here's a Synthetic RGB I did of the Tarantula region (Ha=R,OIIIG=G,OIIIB=B)...
http://s327.photobucket.com/albums/k...current=27.jpg
Though the colours may not be everyone's cup of tea - I love the drama of the results!!!
Although the DSLR isn't firing on all cylinders with regard to NB response/sensitivity, I don't think it lives up to the bad press some have given it.
Your praise for the Cooled DSLR has give me some Hart (pun intended)
Doug
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19-04-2010, 09:40 PM
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Moderator
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Join Date: Apr 2005
Location: NEWCASTLE NSW Australia
Posts: 33,205
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Thanks Phil for your input - thats why i like the cooled DSLR
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22-06-2010, 01:41 PM
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Hard to soar like eagles.
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Join Date: Feb 2010
Location: Adelaide
Posts: 401
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A quick question - are the modded cameras still 100% usable in daylight for general photography or are screw on filters etc required?
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22-06-2010, 02:04 PM
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Moderator
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Join Date: Apr 2005
Location: NEWCASTLE NSW Australia
Posts: 33,205
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filter required
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22-06-2010, 02:16 PM
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Buddhist Astronomer
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Join Date: Aug 2009
Location: Phillip Island,VIC, Australia
Posts: 4,073
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Ha the only option missing was not owning a DSLR yet
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22-06-2010, 02:40 PM
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IIS Member #671
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Join Date: Dec 2005
Location: Canberra
Posts: 11,159
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Wayne,
You can use a UV/IR modified camera perfectly well for terrestrial use.
What you will need to do, however, is correctly white balance in post processing. This is a simple matter of either using a white balance card/disc and making sure you've got a photograph of it in the lighting conditions that you'll be shooting in so you can simply click on the card in post processing and use it to set your white point. With Canon's, you can ensure the card fills your centre spot in the viewfinder, take an image, and set custom white balance (Nikon's require the full frame to be filled with the card), or, lastly, you can just simply click on something which is white (neutral grey) in post processing to set your white balance.
I have found, in general, whilst using expensive white balance cards, gets your colours spot on, it leaves your images looking rather clinical and academic.
For a studio situation, this would be perfect, however, when you're trying to balance multiple light sources of differing types.
H
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22-06-2010, 05:57 PM
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Bust Duster
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Join Date: Nov 2008
Location: Brisbane, Australia
Posts: 4,846
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I bought one of the filters that were supposed to bring the WB on modded cameras back to what an unmodded one is. Rubbish. Still had to custom WB everything so you're better off just using no filter and doing the same.
After a little experimenting I found the custom WB settings (tint and temperature) to set the camera at that gives a pretty pleasing results without editing. Doesn't really mean anything because I shoot RAW, but means that if you chimp the images on the camera LCD they don't have that pinkish tinge, they're pretty close to what you want.
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22-06-2010, 06:38 PM
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Registered User
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Join Date: Aug 2005
Location: Hahndorf, South Australia
Posts: 4,302
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Quote:
Originally Posted by Adelastro1
A quick question - are the modded cameras still 100% usable in daylight for general photography or are screw on filters etc required?
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Agree with what H and Troy have said regarding white balance issues, but if you're talking about using a cooled/modded DSLR for terrestrial use then I've heard there can be gradient issues. I recall Paul Haese commenting on this problem with his cooled 40D.
Paging Paul!!!!
Cheers
Doug
EDIT...found the reference
http://paulhaese.net/40Dreview.html
Paragraph under "Working"
Last edited by dugnsuz; 22-06-2010 at 07:38 PM.
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25-07-2010, 07:09 PM
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Registered User
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Join Date: Jan 2007
Location: Gateshead
Posts: 2,205
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My 40D is neither cooled or modded.
Looks very easy to cool a DSLR if you think there is real benefit that can be gained over ICNR.
http://ghonis2.ho8.com/rebelmod450d16c.html
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01-08-2010, 12:08 AM
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Registered User
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Join Date: Jan 2009
Location: Adelaide
Posts: 9,966
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Sorry just found this thread Doug.
I had some slight trouble doing darks with my 40D during daylight hours. I found I was getting a gradient near the bottom of the image. As it turned out it was caused from a slight light leak brought about by the cooling modification. The camera cannot be used for terrestrial use as a result but it does fine work at night. Not really an issue for me but if you only own one camera it may be cause for concern.
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26-11-2010, 02:19 PM
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Registered User
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Join Date: Nov 2010
Location: Ormeau Gold Coast
Posts: 2,067
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Someone said to me that you can use a stored different shade whitebalance to restore daylight function, but I'm sure that they'd have incorpporated that into the camera if they could do it just with that. it may however improve the situation
Adding an IR filter would restore the situation no doubt though.
I voted that I had an unadulterated DSLR - but I haven't actually got it to hand, though it is paid for, should arrive quite soon.
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26-11-2010, 04:40 PM
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daniel
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Join Date: Sep 2007
Location: Macedon shire, Australia
Posts: 3,426
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i still can't see the value in 1500 for the cooling box - i will go looking for a small pelt in one of those cooling drink holders & fashion my own box i think - better yet i'll just shoot in winter
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26-11-2010, 04:44 PM
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Registered User
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Join Date: Nov 2010
Location: Ormeau Gold Coast
Posts: 2,067
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Get a eutectic cell from a cup warmer for the car - the other side is a cooler - which can drop the temp by about 20C below ambient. They have a fan etc
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26-11-2010, 10:04 PM
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Registered User
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Join Date: Aug 2005
Location: Hahndorf, South Australia
Posts: 4,302
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Quote:
Originally Posted by dannat
i still can't see the value in 1500 for the cooling box - i will go looking for a small pelt in one of those cooling drink holders & fashion my own box i think - better yet i'll just shoot in winter
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Quote:
Originally Posted by jenchris
Get a eutectic cell from a cup warmer for the car - the other side is a cooler - which can drop the temp by about 20C below ambient. They have a fan etc
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Those coolers are essentially what I got for $1K in a professionally modified form!!
But try rapidly cooling your sensor with them - the trick is cooling the sensor not the camera chassis, and that's where I see a major part of the value of this type of mod over the 'camera in a coolbox' method.
Granted, guys like Bert (avandonk) have great success with the coolbox method - but his cooler isn't a simple box with peltier cooler attached.
From web research it seems the most efficient methods employ some type of 'cold finger' on the sensor. The most linked to mod on the web (Gary Honis I think!?) using the cool box gear referred to above can achieve a temp drop of around 20ºC as I recall - but will take around 2 hours to get there.The Central DS cooled DSLR will achieve that drop plus more (approx 30ºC for me last night) in a couple of minutes - major plus.
But I'm really probably making excuses for my lack of DIY tech skills too - I don't think I could make an efficient cool box that I would be happy to stick my 40D in.
Other things of value over CCD ,for example, to me are...1.I don't have to radically change the way I have been imaging for years as it suits me, 2.Live View focusing - simple, 3.ability to use all my Canon EF lenses without adapters (custom made - expensive too!) - my imaging passion , 4.ability to frame and compose the image through the viewfinder and 5.compact nature of the Central DS design - I can't have a large heavy insulated box hanging off my lenses.
And, you can still use it as a normal but heavy DSLR - so it gives you an arms workout too!
And that concludes the case for the defence m'lud!
Doug
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30-11-2010, 11:41 AM
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Registered User
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Join Date: Nov 2010
Location: Ormeau Gold Coast
Posts: 2,067
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How hard would it be to direct a stream of cooled air into the cavity of the camera?
If it has been past a cold cell, the humidity would be low so there wouldn't be condensate on the air stream.
a small stream of modulated temperature air across the face of the lens wouldn't be disastrous to the 'view' and the cavity would quickly cool to 20c below ambient.
The air could be returned to the cell for recooling - so the humidity would remain constant.
It could literally be two tiny air tubes attached to the camera and no weight. The cell could be hung onthe tripod!
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01-12-2010, 10:29 PM
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Registered User
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Join Date: Aug 2005
Location: Hahndorf, South Australia
Posts: 4,302
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Quote:
Originally Posted by jenchris
How hard would it be to direct a stream of cooled air into the cavity of the camera?
If it has been past a cold cell, the humidity would be low so there wouldn't be condensate on the air stream.
a small stream of modulated temperature air across the face of the lens wouldn't be disastrous to the 'view' and the cavity would quickly cool to 20c below ambient.
The air could be returned to the cell for recooling - so the humidity would remain constant.
It could literally be two tiny air tubes attached to the camera and no weight. The cell could be hung onthe tripod!
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Time to take the jeweler's screwdrivers to that new 450D and find out Jenny!?
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02-12-2010, 08:29 PM
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Registered User
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Join Date: Jul 2005
Location: maryland newcastle AUSTRALIA
Posts: 1,829
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I got to agree with Doug i went down the path of building a cooler box out of a warmer cooler and found all i could get out of it was a temp drop of about 9 deg and this took about a hour to do so,also by the time you sealed it all up it actually was quite heavy,and if you wanted to change any of the controls on the camera you had to open up the box andthen your temp rose not to mention you do get condensation inside the box water and elec dont go together.i brought mt 40d and had it cooled at central ds its compact and works brilliantlly cools down to-5 in minutes and comes with a external temp gauge.i should have just kept the box for cooling the beers.
AL
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