Orpington Astronomical Society

Astronomy => Technical => Topic started by: MarkS on Jun 02, 2008, 10:39:13

Title: Modding a Canon EOS 300D
Post by: MarkS on Jun 02, 2008, 10:39:13

Does anyone know where can I get a replacement IR filter for my Canon EOS 300D?  I've become increasingly frustrated over the lack of H-alpha sensitivity and so I've decided to go down the DIY modding route ...
Title: Re: Modding a Canon EOS 300D
Post by: Ian on Jun 02, 2008, 11:27:36
no, but good luck :)

If you want to borrow my large hammer let me know. I doubt you'll need a blowtorch.

Unless something needs cleaning, of course.
Title: Re: Modding a Canon EOS 300D
Post by: Mike on Jun 02, 2008, 12:03:23
Ooh sounds risky. Fingers crossed.
Title: Re: Modding a Canon EOS 300D
Post by: Ian on Jun 02, 2008, 12:06:55
Mike,

have you ever tried to do delicate technical things with crossed fingers? I tried once, I flicked the screwdriver right across the room...
Title: Re: Modding a Canon EOS 300D
Post by: mickw on Jun 02, 2008, 12:18:49
Is this what you're looking for ?
Astronomik clip filters
http://www.modernastronomy.com/
http://www.modernastronomy.com/filtersAstronomik.htm#aCls

Various filters to fit EOS.
Title: Re: Modding a Canon EOS 300D
Post by: Fay on Jun 02, 2008, 13:50:57
Mark,

//www.maxmax.com/aXNiteFilters.htm

I think filter CC1.

This info is given on the Astronomiser site.

Title: Re: Modding a Canon EOS 300D
Post by: Fay on Jun 02, 2008, 13:51:37
Sorry Mark but the CC1 filter is the one to make the camera work normally after a mod.
Title: Re: Modding a Canon EOS 300D
Post by: MarkS on Jun 02, 2008, 16:17:45

Thanks Mick but unfortunately they're not the filters I'm after.  It's the internal IR filter in front of the CCD that I want to replace and it requires disassembly of half the camera (with or without my fingers crossed!) to get at it.

I've now found 2 potential suppliers of the required Baader replacement filter:
David Hinds (Celestron UK)
Telescope Service (Germany)

But the item is on back order at both suppliers.  Probably available in 1-2 weeks.

So put some observing sessions in your diary - whilst my camera is out of action there'll be guaranteed clear skies with  perfect seeing and transparency.
Title: Re: Modding a Canon EOS 300D
Post by: JohnP on Jun 02, 2008, 16:42:16
Mark - for some reason I have Edmund Scientific or Edmund Optical in my head.... don't know if either of these can help?

John
Title: Re: Modding a Canon EOS 300D
Post by: MarkS on Jun 20, 2008, 01:35:57

Thanks John

I gave up waiting for the Baader replacement IR filter so I ordered some plain glass from Edmund Optics.  It arrived today (I ordered it only yesterday), so tonight I modded my EOS300:

Partway through the procedure:

(http://homepage.ntlworld.com/the_shelleys/photos/mod1.jpg)

The sensor is now exposed:

(http://homepage.ntlworld.com/the_shelleys/photos/mod2.jpg)

The sensor removed:

(http://homepage.ntlworld.com/the_shelleys/photos/mod3.jpg)

The Edmunds optics glass now had to be cut to size to replace the Canon glass

Procedure completed.  First (infra-red) light from the TV remote control!

(http://homepage.ntlworld.com/the_shelleys/photos/mod4.jpg)

All in all it took 3.5 hours.  Now I just need another clear night to do the Dumbbell Nebula again - this time in glorious Hydrogen Alpha ...

Title: Re: Modding a Canon EOS 300D
Post by: JohnP on Jun 20, 2008, 07:06:24
Wow Mark - I'm very impressed - no messing.  3.5hrs is very impressive especially seeing its your first time to do it... What was the Baader filter going to offer?? How did you cut the glass to size?

John
Title: Re: Modding a Canon EOS 300D
Post by: Fay on Jun 20, 2008, 08:03:20
Mark, you are very clever to have done that mod, just like that.

I went outside with mine, again, last night, but  I have not got what I would call a normal looking image yet, as the sky is so light. They are very light pink, at 30secs @ ISO 400. There were a lot of thin white clouds going past all the time as well. I tried different ISO's & exposure times, but think I will have to wait until it gets a bit darker.

Fay 
Title: Re: Modding a Canon EOS 300D
Post by: MarkS on Jun 20, 2008, 08:28:42

John,

Once I removed the old IR cut filter I used a glazier's glass scoring tool to score and break the new glass to the same size. 

All the instructions are on this site: http://ghonis2.ho8.com/rebelmod.html

The filter that Baader provide (already cut to size!) is a UV/IR cut filter.  Since I used glass instead, I'll now have to use an external IR cut filter or a CLS filter.

However it does mean that I can use the camera for IR photography now (if I get an IR pass filter).

Mark
Title: Re: Modding a Canon EOS 300D
Post by: MarkS on Jun 20, 2008, 08:37:09
Fay,

Do you know what they replaced your filter with?  Is it another IR filter or just plain glass?

Mark


Title: Re: Modding a Canon EOS 300D
Post by: Ian on Jun 20, 2008, 08:41:35
Nice one Mark. I see on the last photo you hadn't cleared away the most important tool when pulling the guts out of sensitive electronic equipment...
Title: Re: Modding a Canon EOS 300D
Post by: Fay on Jun 20, 2008, 09:04:25
Mark, is has a Baader UV IR filter in place.
Title: Re: Modding a Canon EOS 300D
Post by: MarkS on Jun 20, 2008, 09:20:31

You're right Ian.  Never attempt jobs like that whilst sober!