Canon 450D mod ??

[icebergahed]

Hi all

I am considering dropping the IR filters out of my DSLR which i never use for anything else but astro.

Ive seen word about Astronomik clip or Badder. Im not quite what this is. Is it something i need to get to replace?????

Thanks

[LightBucket]

Just been chatting about this on another thread...

You have different options, one is to do the “normal” Astro mod when you remove just the LP1 filter and, leave the other in place as that gives really good IR cut, or take them both out and replace one with a Baader glass which gives IR cut...

I personally don’t see the point of the Baader replacement, just take out the one filter and increase the red response.... simples

[LightBucket]

After you have done the mod if you then suffer from LP you could consider the CLS clip filter, of which there are two versions, CLS and CLS CCD, the difference is that the CCD version has IR cut, which you don’t need if you do the normal Astro mod, as the filter left in the camera does this, so just get the cheaper CLS, the CCD version is for CCD cameras or DSLR camera that have had full spectrum mod and both filters removed.. HTH

[icebergahed]

Ok i thought removing the IR filter was the idea ? I assume LP1 stands for light pollution?

What is 'shimming' the chip??? And is this something i need to do? 

[LightBucket]

5 minutes ago, icebergahed said:

Ok i thought removing the IR filter was the idea ? I assume LP1 stands for light pollution?

What is 'shimming' the chip??? And is this something i need to do? 

Both filter cut IR, but one also cuts the red signal too, this is the one you remove...and no it does not stand for light pollution...

leaving the other filter in place means you still have IR cut in the camera, which you need when imaging, especially with a lens or refractor telescope.

Shimming the sensor is so that the autofocus will still work for a camera lens, but really for astro work when using a telescope it is not needed as you will focus the telescope, but if you want to use with a lens for daytime photography then yes it is something you need to consider..

[icebergahed]

I found this image looks there may be 2 LP filters for the 450D that need removing.

[Mick J]

Two other threads modding a 1000d, much the same as the 450d - first - second.

Worth a look over (especially as John may be starting this afternoon and updating later) the same filter picture is discussed in one of those threads.

If you go for it good luck, I think most manage first time,  mark a line on the ribbon cables with a felt tip pen then reset to same depth on reassembly, most problems seem to be badly connected cables.

[Stub Mandrel]

450D you leave the low pass (UV) filter in place and it protects the chip without affecting imaging.

[icebergahed]

4 hours ago, Mick J said:

Two other threads modding a 1000d, much the same as the 450d - first - second.

Worth a look over (especially as John may be starting this afternoon and updating later) the same filter picture is discussed in one of those threads.

If you go for it good luck, I think most manage first time,  mark a line on the ribbon cables with a felt tip pen then reset to same depth on reassembly, most problems seem to be badly connected cables.

Thanks Mick

That was a educational read for me. However John was going with a full spectrum mod. I THINK im aiming to let more red spectrum through. So would i be right in saying i would only be removing LPF-2/IR cut section and leave LPF-1 in?

[Mick J]

It was along time ago when we did ours (my disclaimer), I am not sure what John decided to go for - we shall see.  I can remember having to break the filter out of the plastic surround and breaking the filter, I am pretty sure it was the one marked 'IR Cut Filter' and believe we left the Low Pass Filter -1 alone.

We replaced the filter with an Astrodon filter to help keep focus, if I were to do it again I would not replace, camera is only used for astro.

Hope that's helpful, expect John has taken pictures and will post later.

[SilverAstro]

7 hours ago, Mick J said:

Two other threads modding a 1000d, much the same as the 450d - first - second.

and his third, describing his results is here 

in which he discovers that eye protection is ESSENTIAL ! when removing the glass filter   !!! crikey it could have been much much worse

Quote from John @JohnSadlerAstro  " Fortunately, the glass went right into the corner of my eye, or it could have been quite serious.
Wear safety glasses when dismantling and reassembling the filters.  "

[JohnSadlerAstro]

I am being discussed. 

I went for a "half way house" modification, removing the "IR Cut filter", but not the "Low Pass Filter #1". This apparently eliminates the need for an external filter.

On the subject of breaking glass and eyewear, once you have safety glasses on the easiest way to remove the filter is to break it section by section. (Keeping your fingers *away* of course! ) It is glued down in a way which suggests to me its not meant to be removed.

EDIT: Don't break the filter you want to keep though, it can damage transparency i believe!  

[SilverAstro]

14 minutes ago, JohnSadlerAstro said:

I am being discussed.

it can damage transparency i believe!  

You have been, ! and we are proud of you (and pleased for you   )

I have just been discussing my 60D with the station manageress and it has been agreed that if/when I want to be modified I shall engage the services of Juan ! Or you if you go into business maybe.

ha! yes, indeed and if you want some more humour (black) it helps if one still has an eye with which to appreciate the end result.

Black #2 if not wearing eye protection do it with one eye closed -  to preserve a spare.   hat&coat >>

gosh !!

 

[JohnSadlerAstro]

With that kind of humour going round, the mods will have to keep an eye on you!  

[SilverAstro]

 

[SilverAstro]

With trepidation, looking over shoulder for mods,

@JohnSadlerAstro said " is to break it section by section. (Keeping your fingers *away* of course! "

aw gosh, no prob., I got 7 of those spare, though at times I think they are all thumbs.

sorry sorry I'll shut up now and await your luvverly pics.

Seriously though, well done, really well done.

[Merlin66]

Simplistically, the front (furthest from the chip) is a "combo filter" - Anti Alias and dust shake. This filter also has good UV-IR rejection and can be retained.

The filter nearest the chip is the Colour Correction filter, which also has some IR rejection. This is the filter to be removed to enhance the red response.

To retain Auto focus the removed filter needs to be replaced with either a clear filter or a Baader etc. This is not required for telescope applications.

HTH

 

[Stub Mandrel]

12 hours ago, Merlin66 said:

The filter nearest the chip is the Colour Correction filter, which also has some IR rejection. This is the filter to be removed to enhance the red response.

This filter has a very apparent pale blue-green colour so its impact on red signals is obvious when you see it.

The first filter appears clear.