Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 01/15/2024 - 10:51

Hello All, 

I'm going to enter into this world, finally after a while. I have to select a camera to start doing my first steps into photometry (I'm reading the AAVSO guides/manuals).

options are:

- KAF 8300 (full well 25Ke, 16 bit, cooled)

- IMX533 (full well 50ke, 14bit, cooled)

- IMX432 (full well 97ke, 12bit, uncooled)

Considering I already have the IMX432, I'm attracted from its large full well, but I also can purchase for around 550USD an Atik383L+ or go to an IMX533 cooled. Which might be the preferred choice between these sensors, considering full well and cooling? Your feedback will be really precious, thanks and have clear skies,

Riccardo

Affiliation
American Association of Variable Star Observers (AAVSO)
Some thoughts

In general I would go for a camera with cooled, 14bit or better, modern mono CMOS sensor with high quantum efficiency, and a sensor size that matches your existing equipment. To do photometry with a mono camera, you will also want to have at least one photometric filter for most applications, better two, and later more.., plus a filter changing thingy, and that needs to be considered for the budget because these filters are not cheap...but filters are a different topic.

It also depends a bit on how long you will want to use this in terms of an investment for the future. The KAF 8300 was released by Kodak around 2005 IIRC, so now the design is already almost two decades old. Since then Kodak sold  the CCD sensor fabrication, and the final buyer ON Semi shut down its production fab in mid 2020. So every "new" KAF 8300 sensor you buy now must have spent *at least* 3.5 years already sitting on some shelf. In the meantime people who were desperate to replace defective KAF 8300 in existing equipment or stock them for warranty claims drained the remaining supply, and I'm not sure the remaining supply now is necessarily the pre-selected best-quality stuff. If you plan to use this camera for, say, 15 years, note that at the end of this period a KAF 8300 will truly be vintage equipment.

No offense to vintage or new-old-stock equipment, tho..but since the early 2000s, image sensor technology has progressed and especially the Quantum Efficiency (QE in datasheets) is significantly higher now, so that the photons hitting the sensor have a higher chance to be registered in your final image, also read-out noise is lower => you need less exposure time to get photometry with the same photometric uncertainty => higher productivity.

Just my 2 €cents 

HBE

Affiliation
American Association of Variable Star Observers (AAVSO)
Hi, 

your 2 cents were…

Hi, 

your 2 cents were extremely useful, thanks for your point of view. I will search our a 14bit cooled CCD camera. I noted Player One released the cooled IMX432 and that might be a good choice: I will try a lineariry test of the uncooled IMX432 to see how it performs (97Ke Full Well are attractive) and then I'll see to move to it in case. 

Affiliation
American Association of Variable Star Observers (AAVSO)
New Camera

Ricardo,

Beware: Always check the field of view of any camera before you buy it to make sure you have a sufficient FOV for photometry. Full well depth is only one factor. I see that the IMX432 camera offered by ZWO is a planetary camera. I would be very careful to check the FOV of that camera before you spend the money. Anything less than 15 arcseconds is problematic and should be avoided because it may be too small to include comparison stars needed for the photometry.

Ed