D5300 vs QHY294C Elephant’s Trunk

One of my best astrophotos with my Nikon D5300 was of the Elephant’s Trunk Nebula. I didn’t use any filters and I found that the small details were very interesting to study.

All of the major details in the Elephant’s trunk are present in both images. The L-eNhance filter seems to bring out even more interesting details. As the Elephant’s trunk stretches upwards you can see that the D5300 image without filters grows vague. The QHY294C+L-eNhance filter image maintains it’s details much further up the Elephant’s trunk. The stars were also easier to process and balance their brightness with this dim nebula with the L-eNhance filtered image.

The other interesting aspect about this comparison is that the D5300 was using ISO200 which is suppose to be it’s equivalent unity gain setting. For the QHY294C, this was one of the few images where I tried using GAIN=2500. I typically used GAIN=1600 which is just above unity gain and where this camera switches to it’s low noise HGC mode. Unfortunately the QHY294C has a problem with fullwell saturation at this setting.

My research tells me that the fullwell limitation affects GAINs from 1600 up to 2500. It may be that removing the fullwell limitation issue at GAIN=2500 contributed to the stars being easier to deal with. The other benefit of using a higher gain is that, for this camera, the read noise become less as the gain increases about GAIN=1600.


March 2021 The latest software release from QHY has fixed the fullwell limitation problem. More to look forward to in 2021.