350D Mod

[Fay]

Well I am thinking of having my Canon 350D modded. I have a Nikon Coolpix 4500, which is compact & takes really nice pictures. Although you cannot see very well what you are taking due to small view on back.

What views has anyone got on this?   Would it be worthwhile?

[MarkS]

Fay, there's only one reason to mod the Canon and that is to improve the hydrogen-alpha sensitivity. 

But I'm thinking seriously of modding my 300D or getting a second hand 350D and modding that.   It will then allow 4x as much H-alpha to come through - and I'll finally get a decent image of the Horsehead!!  I'm beginning to find the lack of H-alpha sensitivity a real frustration.

Remember that after modding, all your conventional photography will have far too much red and you'll have to RGB blance every conventional photo you take (unless you buy a special filter to go over the lens).

[Fay]

Well, I would get the special filter, as long as when it is on, the normal pictures come out the same as before. It is a bit scary to have paid a lot for one of these camera's & messing it about.

There is a lot of difference in the deep sky objects you could get, especially with the large chip. Would the camera be ok with heat, noise etc, Would  you have to let it cook down or anything after taking say 10 minute exposures? 

[Fay]

Mark, would you have to buy a selection of 2" filters for modded camera?

[MarkS]

Fay,

On the noise front, with an outside temperature of 15C or more I begin to notice much more thermal noise. But in the Winter, it's great.  I've never really noticed a problem with the sensor "cooking" i.e. I generally find that the noise characteristics of the 1st sub are very similar to the final sub even with no cooling down time between subs.  It's the outside temperature that has a much greater impact on noise.

Not sure what you mean about a selection of 2" filters.  Yes, any filters you use should be 2" because of the large size of the sensor but the camera is still one-shot colour so you don't need RGB fulters.  But a light pollution filter is useful and there is possibly an argument for an H-alpha narrowband filter.

Throughout the Summer thermal noise will definitely start to become noticeable so I'd love to get a cooled monochrome CCD with a few Megapixels.  But the cost is huge!

[Ian]

Fay, bear in mind the autofocus might go a bit squiffy. Not sure if it applies to the Canon but I'm fairly sure the Nikons don't focus properly once the filter in front of the CCD is removed. I have a feeling you can get filters that fit inside the body rather than screw on the front that make that problem go away, but again I'm not sure.

[MarkS]

Ian, I was assuming that the mod would be a filter replacement rather than simply a filter removal.  Otherwise you are absolutely right - the focussing would be incorrect.

[Fay]

Yes, Astronomiser offers the service of filter change or filter removal.
I have a light pollution filter. It was the thought that if you had to buy even a couple of 2" filters, it would put at least £200 on the price.