DSLR Mod success - which filter then ?

[Vox45]

Hi all!

I followed Gary Honis excellent tutorial to mod my Canon 1000D

Fortunatly, after a lot of planning, all went well... It was actually quite easy to do with the help of:

- the right tools

- this tutorial

- this youtube video

- this screw sheet (!)

The fact that I prepared may explain why it went so smoothly

So I removed LPF2 (low pass filter 2 - color limiting filter) and left the LPF1 (IR/UV) filter in place.

Question is: do I need to add an UV/IR filter when using a 80ED with FR/FF in the imaging train ? will an APO/ED show star bloating or is this only an issue for Achro refractor ?

[MarsG76]

Well done on the successful self mod of your DSLR.

I'd say leave your camera full spectrum and just use the appropriate filters during imaging. Use UV/IR or neodymium filter during RGB captures or a NB filter when narrowband imaging.

Even after removing the LPF there is still another piece of glass over the sensor so your sensor is safe, alternatively just put optical clear glass in place of the LPF.

This approach works well for me.

[Traveller]

Well done on your first camera mod. To answer your question, yes, you will need a UV/IR filter to combat star bloat when using a refractor. (I was told it is not needed on reflectors). I have a modded 1100D and use that with my ED80 and have a EOS Clip in Uv/IR filter.

[laser_jock99]

Ditch the refractor and buy a reflector- no IR/UV filters required!

[Dave_D]

Ditch the refractor and buy a reflector- no IR/UV filters required!

Someone's spoiling for a fight

[Vox45]

Remember that the LPF1 filter IS an UV/IR filter, so there is IR filtering if LPF1 is left intact. Although LPF1 is not as effective as a Baader filter (it still lets some IR pass through as demonstrated in this video by Gary Honis)

I read that the star bloating is only an issue for Achromatic refractor and Apo should be fine... Anyone can confirm that ?

[Vox45]

Some pics

[Astroboffin]

You don't need another IR filter as you left one in the camera, the filter you left in the camera has excellent IR cut, that is one of the main reasons that it is left in the camera during this mod

AB

[Vox45]

You don't need another IR filter as you left one in the camera, the filter you left in the camera has excellent IR cut, that is one of the main reasons that it is left in the camera during this mod

AB

Yes that was my first thought, why add an IR filter when there is still one inside (LPF1) but then I saw this

Now, I am not saying that this will be an issue for me, maybe I won't even see a difference It may depend on the sort of setup people use (reflector vs refractor Apo vs Achro) and DSO targets. So I am not sure if the definitive answer is that I (in my particular case) don't need an IR filter.

[astromerlin]

I've done this mod myself after reading up all the howto's. I left the ir/uv filter in place but if I had to do it again I would remove both filters. The ir/uv filter is also an anti-aliasing filter to prevent moire effects, it also softens the focus somewhat. I dont know by how much but imho I'd ditch both and use an astro ir filter in the imaging chain or cut one to fit the filter shroud before rebuild.

The reflector/refractor debate is a moot point as after doing the mod you will be requiring a nice flat field on your images captured from your reflector so will be using a coma-corrector ie: some glass in the imaging chain.

[Vox45]

Yes, I should have removed both I think there was something about errors with the auto-cleaning element that prevented me to do that, but now I've learned that it only clean LPF1 anyway and you can get rid of the error as explained here:

============================================================================================================

the self clean element, when removed, *on most models* still operates fine(meaning, obviously the self clean element is no longer there, so NOTHING HAPPENS, BUT, the camera WILL go through the self clean routine and not throw up any errors). On other models, you will get an error when you first turn the camera on. Err 70 IIRC. you simply go into the menu and disable the self cleaning routine, and you will be shooting in seconds.

============================================================================================================

I know that most people will be fine with only LPF2 removed, and that removing both filter might be overkill, but going full spectrum and adding a good UV/IR block may improve the image (no anti aliasing and better IR cut as shown in the video I posted above)

Of course, in my case it's a dedicated astro camera, so I do not care about autofocus ability.

There's a good post in CN from a vendor about removing both filters

Now I just sit and wait for expert opinions to contradict all that I just wrote