I just tested my new ASI290MM mini guidecam and was "shocked" to see how good the sensitivity was. Where previously I had to move the finderguider around until I found a star now I have a choice of usually over 20 stars in any direction of the sky.
I thought it would be interesting to compare the 4 (guide)cams that I have here. I know that the comparison is not fair but still it is good to see how the technology improved over time. The image shows:
1. SPC900NC webcam
2. Long exposure modified SPC900NC webcam
3. ASI120MC (90% gain)
4. ASI290MM mini (only 50% gain)
As I said the comparison is not fair in any way and I was not trying to be scientific. I also may have bumped the guidescope while swapping the cameras but the images are still representative of the sensitivity increase that I can see.
Very happy with my purchase
edit: fixed typos