Does QHY offer crop mode shooting?

[FrancoRodriguez]

Hi folks, just thinking about my eventual replacement of 16803 processor in the distant future with a QHY461 and wondering if these cameras or supporting software can be shot in crop mode. Even in 2x2 the files would be 25mb and wondering if for small targets I could get that down further. I can't seem to see any info online

Thanks,
Franco

[Peter Ward]

I use a STXL16803 and QHY600m.

Yes the QHY certainly have sub frame capability.
If you are using MaxIm just draw a box within the frame and select a subframe readout.

Also its CMOS binning does not work in the same way as the CCD. There is no QE improvement but the file size does become more manageable.

Lastly, for ultra dim objects I've found the CCD (when well calibrated) has a lower noise floor than CMOS which has an albeit very faint fixed pattern noise.

[FrancoRodriguez]

Thanks Peter. I use SGP and it doesn't have a crop mode as yet. I wonder if the QHY driver has an option for this? As for the CMOS binning, I'm aware about the lack of benefits with binning c.f CCDs but I was very surprised when I saw the published QE curves of these new BSI sensors. Less in the reds/NIR but still very impressive nonetheless. I'd bin a 102mp camera primarily to reduce the data, nothing else apart from increasing the already impressive well depth

[Peter Ward]

As Maxim can access crop mode, then the driver clearly supports it.

If you don't want to buy a copy of MaxIm , then maybe try NINA?

[gregbradley]

Sky X allows a crop. You click subframe and then draw a box. Or you can set it to half or quarter. I have done that before to get smaller files.

Greg.