Comparison of CCD chips

Any images taken with the colour version?

www.starlight-xpress.co.uk/SXV_M25/m42fullsize.jpg
www.starlight-xpress.co.uk/SXV_M25/m33-fullsize.jpg
www.heavenlyview.com/ngc253sxvm25a.htm
For more images from Alan Chen: www.heavenlyview.com/m25newimages.htm

Cheers,

They're excellent colour shots... Interestingly, the Ha horsehead in mono shows some noise and the imager explains...

It would be a tough choice between the mono and the colour based on those images. Ian King would a good person to ask - and you have the perfect opportunity

Cheers

Dave

The colour shots are excellent.

Another point in the colour side would be better use of the available time, Dave Grennan would be better able to relate his experiance of LRGB to date using a mono imager.

Might be worth email the colour user and asking how much processing he does to get that result.

They look great and would seem to be a good reason to go colour unless he has any horror stories.

Later,

Jed.

Michael, I was just reading an interesting post on Kodak mono and colour CCD's.

I didn't find the KAF-1600C spec sheet either, but usually KAF "C"
and monochrome sensors have exactly the same electrical
characteristics, with the main difference being a filter matrix on
top of the sensor in the C version.

A KAF-1600C chip will be less sensitive than the monochrome version
due to the filter matrix lower light transmission.
The QE plot looks reasonably flat across the visible spectrum, but
it is fairly low at 35%. With the addition of the color filter
matrix, the amount of light reaching individual pixels will be
further cut, often by as much as 66% or more, resulting in much less
light reaching most pixels.

1600C doesn't appear to be very good for deep-sky imaging. It is
also possible that the filter matrix has an IR cutoff filter built- in. If so, the amount of light reaching the pixels will be even
further reduced compared to a monochrome sensor.

Dunno if this helps...

Dave

Dave,

Thanks for the article.

I'm beginning to lean towards the mono chip. Same height as the colour and would be better IMHO for narrowband imaging. The colour is also dearer by a fair bit - most of the price of a filter wheel and RGB filters.
The non chip would take 1.25" filters whilst the colour *may* require a 2" filter wheel and 2" narrowband filters, depending on how close the filter gets to the chip - vignetting etc.
I could get going with the chip in mono for now and get filter and filter wheel at a later date.
It would also keep my options open re doing some science bits. With the colour, this would be very limiting.
The only thing I have against the camera is the level of QE in the red. I would like this to be higher.

Any other cameras one could recommend?

Cheers,

Michael,

Do not be fooled by the maths on this, even though the H16 CAN work with 1.25" filters you will get very obvious vignetting when in use. All starlights come with an T2 adaptor for the front of the camera. In order to get the smallest vignetting the 1.25" filter wheel needs to be very close to the chip. This means you have to take out the starlight supplied T2 and put in a thinner adaptor and then put in enough spacers to achieve focus. I have just moved my filter wheel to the closest possible position but I have had no chance to test it for vignetting. I will let you know how it goes.

PS.The M25C is not the colour version of the H16. The M25C is a Sony chip and the H16 is the first camera produced by Starlight with a Kodak chip.

Kieran