Canon 5D3 astro mod

[Photosbykev]

Good morning folks,

I've been shooting with a stock 5D MkIV attached to the back of a WOZ61 with Flat61A flattener and IDAS-D2 filter. Very pleased with the results I'm getting but I have a spare Canon 5D MkIII which i want to get modified to grab more Ha.

Bearing in mind I would like to use the modded camera with standard DLSR prime lenses as well is the best modification just to remove the UV/IR and Colour correction filter on the sensor leaving the AntiAliasing/UV/IR cut filter in place or remove both and replace with a clear glass filter? I suspect the standard Canon AA/UV/IR filter cutoff is a bit too close to the Ha band so I will lose some Ha data if the AA/UV/IR cut filter is left in place?

If I go down the clear glass filter route I think this means I would need to use a UV/IR filter when shooting with the standard DSLR lenses to avoid bloating and focus problems.

Are there any negatives if I leave the AA/UV/IR cut filter on the sensor for astrophotography with the refractor or with standard DSLR lenses or should I just get the full spectrum modification and then install a Astronomik CLS CCD XL clip-in filter into the 5D3 body and remove the IDAS-D2 filter from the refractor?

best regards

Kev

Edited September 26, 2019 by Photosbykev

[michael8554]

A few points. 

Removing the #LPF1 filter, you loose the cleaning function. 

Correct Autofocus and the ability to manually focus to infinity can be achieved by repositioning the sensor, often included by professional modding services. 

It's not clear to me how much more Ha you get by removing both filters. 

Michael 

[Merlin66]

There’s no further increase of the Ha sensitivity when the front filter element is removed. It does allow recording from Uv to NIR for spectroscopy.

I have the full FULL Canon mod and had to add a clip in clear filter to allow focusing with camera lenses.

 

[Photosbykev]

Thank you folks, sounds like just the rear filter needs to come out to take advantage of normal DSLR lens as well as the refractor. I'm not too bother about AF as the camera will be dedicated to astro work so all manual anyway but obviously reaching infinity with dslr lenses is pretty important

 

Now all I need is just one modification company to reply to my email. 3 companies emailed in the UK and not one reply so far

 

Kev

Edited September 27, 2019 by Photosbykev