An unscientific comparison...

[Psychobilly]

The sunlight coming throught the bedroom window hit the chamfered edge of the mirror throwing a spectrum onto the bedroom door...

So I quickly grabbed the 3 DSLR's I had to hand and snapped the spectrum with each...

Peter...

[Demonperformer]

Interesting test.

Don't really understand what I am seeing, but obviously the 1000D is giving a completely different result to the other two. As I use a 1000D for my astropics, does this mean I will be getting wrong colours?

Thanks

[blinky]

Yeah, why is the whole response pinkish? I expected the red end to be redder but the whole response?

[brantuk]

Well - I don't know anything about filters really but I just googled the baader bcf and came up with this link:

400D/40D BCF Baader Corrector Filter [baa-45-2459213] - £43.00 : 365Astronomy: Discovery for every day!

Don't know if it explains anything about the phenomenon but I'd be intersted to know what people think.

[Starblazer]

I am guessing that the modifications made to the 1000d in removing the IR /UV filter then replacing it with a clip filter that allows more IR/UV through, is probably what this is showing.

The first 2 images only look right to us as our eye's filter the ir/uv out so we see the spectrum clearer or should I say, more like we would expect to see normally.

Kinda similiar to our atmosphere scattering/filtering blue light more than yellow/red and therefore the sun looks yellow/orange when it's actually yellow/green.

[Psychobilly]

The 1000D has a BCF mod and Astonomik CLS-CCD Clip in fitted (does actually say that onthe pic) the other two are un-filtered...

[Psychobilly]

Ok Try These...

All shot at 50mm FL NO filters on lenses ISO400 Daylight White Balance as Jpegs

The spectra (still not sure what generating it in the bedroom) was reflected onto a sheet of A4 white paper blutacked to the bedroom door...

Nikon D200 (Standard)

Canon 550D (Standard)

Canon 1000D Baader BCF Replacement filter

Canon 1000D Baader BCF Repalcement Filter + Astronomik CLS CCD Clip In

[blinky]

Looking at the last image, it just shows why I find it so hard to get any star colour when using a CLS filter!

[Psychobilly]

Thats where the Hutech IDAS P2 scores....... need to blutack it to the front of the 50mm for comparison .. not today though as its sitting on the FFIII in the 72 at the moment...

It also explains why my GLP Painting didnt work the other night

Peter...

[Psychobilly]

Spoken to SCSAstro (UK Hutech Distributor) the IDAS is now available in what Hutech call "Front Filter" format which is their version of the Clip in System like the Astronomiks use ...

The list price in the US is $249 so waiting for a UK price and delivery... it's also been "improved" to V4...

Peter

[barkis]

Would correcting White Balance Indoors not improve the 1000D Peter?

Like I know what I'm talking about:D.

Ron.

[Psychobilly]

Hi Ron,

The modified 1000D response is ideal for astro... The CLS-CDD is very good but harsh LP filter making it difficult to get any "yellowish stars"...

I much prefer the Hutech IDAS .. so now its available as a clip in ... provided the UK price is right I just got to have one

Peter...