Canon 450D astro mod

[Coastliner]

Hi, I am considering going for modding my camera, it seems I have a choice whether or not to have a Baader filter fitted. I would like to know if the Baader reduces the quality of the astro images? I would like to have the Baader so that I can use the camera in daytime but not at the expense of astro quality.

Thanks,

Neil.

[barkis]

The reason for the Baader  ,  is to permit the Ha response,  but also to allow normal terrestrial photography.     I molded my 1000D camera using the Baader replacement, and it performs well on both   Sky and normal AP.  Set the White Balance  for earth based photography.      Cleanliness during the mod.  Is vital to keep the sensor free from contamination.  Use non volatile silicon adhesive,  get some medical forceps.  They will help with the removal and reinstallation of the various ribbon cables,  get a pill box to  place all the small screws in,  and label the sections in the various steps in the procedure. Can't be too careful.     Good Luck

 

[SkyBound]

14 minutes ago, barkis said:

The reason for the Baader  ,  is to permit the Ha response,  but also to allow normal terrestrial photography.     I molded my 1000D camera using the Baader replacement, and it performs well on both   Sky and normal AP.  Set the White Balance  for earth based photography. 

Hmmmm,

I though the reason for the Baader was not to permit Ha response, the reason for the removal of the filter in the first place is for that, after removing the filter the autofocus is usually a bit out, when used with a normal camera lens,  so by putting another filter in place of the removed one, it brings auto focus back again with a lens fitted, but the filter that is put back must allow the Ha light to pass through or it would be counter productive.

also after the filter removal, all images look very red...which is normal, so by putting the Baader filter in it corrects the colour balance, so the camera can then be used for night and day imaging, without having a red cast on the images.

If you choose not to fit the Baader and just leave out the filter, (which I and many others have done) it will work perfectly for Astro work, but not so good for daytime without using a custom white balance to correct the red cast, and the autofocus will be slightly off if you want to use with a lens.

hope,that helps a bit

 

Edited September 18, 2016 by SkyBound

[Jokehoba]

58 minutes ago, SkyBound said:

I though the reason for the Baader was not to permit Ha response, the reason for the removal of the filter in the first place is for that, after removing the filter the autofocus is usually a bit out, when used with a normal camera lens,  so by putting another filter in place of the removed one, it brings auto focus back again with a lens fitted, but the filter that is put back must allow the Ha light to pass through or it would be counter productive.

also after the filter removal, all images look very red...which is normal, so by putting the Baader filter in it corrects the colour balance, so the camera can then be used for night and day imaging, without having a red cast on the images.

If you choose not to fit the Baader and just leave out the filter, (which I and many others have done) it will work perfectly for Astro work, but not so good for daytime without using a custom white balance to correct the red cast, and the autofocus will be slightly off if you want to use with a lens.

The Baader filter is designed to extend the IR range enough to allow transmission of Ha while still blocking UV/IR at the extremes. @barkis is correct.

Simply removing the stock filter without putting another in it's place would be a 'full-spectrum' mod and would require an external filter to block unwanted UV/IR. 

Edited September 18, 2016 by Jokehoba

[John78]

I'm going through this decision making process myself, if I simply remove the filter I thought too much IR would get through and give you fuzzy images as the focus would be off for the IR although on nebulous images it might not be noticeable.

Astronomik make a clip filter with the same band pass as the baader so you can put it in front of the mirror, or the CLS which blocks the sodium from street lights.  So many decisions, I'm confident I could take it apart, remove the filter and rebuild the camera - less confident about fitting the baader in its place ?

[barkis]

Mmm! seems I got my wires crossed a bit. Apologies If I misled the OP.
I should have gone over my own notes before jumping in. 

[SkyBound]

These Canon cameras have two filters in place, LP1 and LP2 and removing just one (normal Astro mod) is NOT a full spectrum mod, you have to remove both for it to be a full spectrum mod, as then the full spectrum of light can pass through to the sensor.

so the second filter is left in place, and this is because this filter has very good IR cut, but does not stop the Ha signal, so it can be left in place.

so to simplify.....

two filters both cut IR but one also cuts Ha, so just remove the one that cuts both, and leave the other so you get IR cut, which is what you need for digital Imaging, if you do remove both (full spectrum mod) then you would then need an IR filter fitted somewhere in the imaging train, especially if using a frac.

 

again, I hope that clears a few thing up

[SkyBound]

9 hours ago, Jokehoba said:

The Baader filter is designed to extend the IR range enough to allow transmission of Ha while still blocking UV/IR at the extremes. @barkis is correct.

Simply removing the stock filter without putting another in it's place would be a 'full-spectrum' mod and would require an external filter to block unwanted UV/IR. 

You would have to remove BOTH filter in these cameras for it to be a full spectrum mod, as the second filter is left in place to give IR cut....that is the normal Astro mod

1 filter just cuts IR (left in place) and the second one cuts IR and Ha so is removed.....

[SkyBound]

4 hours ago, John78 said:

I'm going through this decision making process myself, if I simply remove the filter I thought too much IR would get through and give you fuzzy images as the focus would be off for the IR although on nebulous images it might not be noticeable.

Astronomik make a clip filter with the same band pass as the baader so you can put it in front of the mirror, or the CLS which blocks the sodium from street lights.  So many decisions, I'm confident I could take it apart, remove the filter and rebuild the camera - less confident about fitting the baader in its place ?

Please see my posts above..

[Coastliner]

Thanks all, your passing on of knowledge is appreciated. So, I have newbie question off the back of this (sorry, I'm of an age now where monosyllabic answers are required :-) ) - getting the nice red nebulosity around images is not down to IR/UV but is down to Ha? And therefore we have decided that we need to continue blocking IR but let Ha through?  LP1 and LP2 - which one of these should be removed, and is it the one nearest the sensor or the furthest away?  Where are the best instructions I can find for doing this myself?

 

[Davey-T]

http://dslrmodifications.com/rebelmod450d17.html

https://www.youtube.com/watch?v=-IIN0-q2WLY

Dave

Edited September 19, 2016 by Davey-T

[SkyBound]

1 minute ago, Coastliner said:

Thanks all, your passing on of knowledge is appreciated. So, I have newbie question off the back of this (sorry, I'm of an age now where monosyllabic answers are required :-) ) - getting the nice red nebulosity around images is not down to IR/UV but is down to Ha? And therefore we have decided that we need to continue blocking IR but let Ha through?  LP1 and LP2 - which one of these should be removed, and is it the one nearest the sensor or the furthest away?  Where are the best instructions I can find for doing this myself?

 

You are correct, you need to let the Ha through to get the nice red images...  not down to IR, that should always really be blocked, unless you are a full spectrum imager,...and that's another topic.....

and yes you still need to block IR because it causes star bloat especially on refractor scopes.

there are two filters, and this may help...it's the rear one next to the sensor you need to remove...

 

 

[Coastliner]

Thanks Skybound, I'm getting more and more tempted to have a go. Looking for instructions now....

[SkyBound]

1 minute ago, Coastliner said:

Thanks Skybound, I'm getting more and more tempted to have a go. Looking for instructions now....

Look at the links that Davey-T posted....above

[John78]

Ah ok - so I'm happy now, rip out the one that's in the YT video only and it'll still block past ~700nm.  Sounds like a job for this weeks cloudfest.

[Davey-T]

1 minute ago, John78 said:

Ah ok - so I'm happy now, rip out the one that's in the YT video only and it'll still block past ~700nm.  Sounds like a job for this weeks cloudfest.

Make sure you've got a set of tiny cross head screwdrivers.

Dave

[Coastliner]

I'm going for it. I'll be removing the IR filter glass nearest the sensor and replacing it with nothing. I have gloves and an anti-static grounding mat, I'm going to see if Argos sells the modelling knife with the chisel blade.

[Jokehoba]

2 hours ago, SkyBound said:

You would have to remove BOTH filter in these cameras for it to be a full spectrum mod, as the second filter is left in place to give IR cut....that is the normal Astro mod

1 filter just cuts IR (left in place) and the second one cuts IR and Ha so is removed.....

OK, I stand corrected wrt full spectrum.  

It was several years ago that I did my Canon mod (as per Gary Honis' guide), and I substituted the stock filter with the Baader ACF. He states that the reason to replace the filter was to restore auto-focus capabilty as well as blocking 'higher infrared wavelengths that cause poor focus and bloated stars with refractor telescopes and camera lenses.'

[SkyBound]

46 minutes ago, Coastliner said:

I'm going for it. I'll be removing the IR filter glass nearest the sensor and replacing it with nothing. I have gloves and an anti-static grounding mat, I'm going to see if Argos sells the modelling knife with the chisel blade.

Yes you must remember if you leave an empty space where the filter is removed from, you will loose autofocus with a lens, but if only to be used on a telescope it's not a problem.

when done by the professionals, like Juan at cheap astrophotography, they shim the sensor so as to keep auto focus working, but I am not exactly sure how they do this...

good luck, see you on the other side, and let us know how you get on, just remember to label all the screws as they are removed, and use a wooden tooth pick or similar to remove the ribbon cables, as this should not damage them....

[SkyBound]

1 hour ago, John78 said:

Ah ok - so I'm happy now, rip out the one that's in the YT video only and it'll still block past ~700nm.  Sounds like a job for this weeks cloudfest.

In a nutshell yes, the filter nearest the sensor is to be removed.....

[Coastliner]

"Wish me luck as you wave me goodbye, cheerio, here I go, on my way...".  I'll be back :-)

 

[Jokehoba]

6 hours ago, Coastliner said:

I'm going for it. I'll be removing the IR filter glass nearest the sensor and replacing it with nothing. I have gloves and an anti-static grounding mat, I'm going to see if Argos sells the modelling knife with the chisel blade.

Best of luck...but I'd still recommend fitting the Baader filter.

[SkyBound]

57 minutes ago, Jokehoba said:

Best of luck...but I'd still recommend fitting the Baader filter.

Makes the mod a lot more expensive though..... ?

[Adam J]

20 hours ago, Jokehoba said:

Best of luck...but I'd still recommend fitting the Baader filter.

Totally depends on the rest of the imaging chain. The front filter in the canons is a little less aggressive then the Baader replacement (750nm cut as opposed to 690nm cut) so it will depend on the quality of your optics with a refractor. However, if like me you are using a Newtonian adding a Baader UV/IR filter in addition to the front filter is a complete waist of time even if you are using a coma corrector. If you have a refractor of suspect quality you could kill two birds with one stone and get a CLS CCD filter as that will cut the IR just as well as the Baader replacement filter and you have a LP filter for the price too.

Edited September 20, 2016 by Adam J
Not sure what a retractor is but my system keeps auto correcting to it from Refractor.

[SkyBound]

17 minutes ago, Adam J said:

Totally depends on the rest of the imaging chain. The front filter in the canons is a little less aggressive then the Baader replacement (750nm cut as opposed to 690nm cut) so it will depend on the quality of your optics with a retractor. However, if like me you are using a Newtonian adding a Baader UV/IR filter in addition to the front filter is a complete waist of time even if you are using a coma corrector. If you have a retractor of suspect quality you could kill two birds with one stone and get a CLS CCD filter as that will cut the IR just as well as the Baader replacement filter and you have a LP filter for the price too.

Excellent advice

exactly what I have done, got the CLS CCD filter