ASI174 and ASI290 mini camera have very beautiful outlooks, small size, lighter weight, this is not a big deal.
We should consider much more…
How to choose a good guide camera?
Many people may say : it must be small, suitable for different equipments(guide scope, OAG), stable working.
Yes, I think thoes are basic demand for a good guide camera, and ASI mini camera can do them well.
So, what else we do care in the deep of our mind?
I think there will be three potential requests: high sensitivity, precisely guiding, big FOV.
Sensitivity is the first thing we considered. it is very important to look for a guide star. So at the beginning, we were considering to use mono sensor to design our guide camera only. Because mono sensor has much higher sensitivity than color ones. After that, we carefully compared the sensitivity of our sensors. At last, we decide to use 290 and 174 mono sensor. As we know, 290 and 174 mono sensor have about 80% QE peak, can detect more stars in view. Also, we can shorten the exposure time in guiding.
ASI290 mini is designed for precisely guiding. 2.9um pixel size can give you a higher arcsec/pixel than 224 or 120 camera. Which means in same guide scope, 290mini can detect slighter movement of stars. ASI290 mini can improve about 30% guide precision than 120mm.
ASI174 mini is designed for Big FOV guiding. This is very useful in OAG to looking for a guide star. When you using OAG guider to work with Ritchey-Chretien or Schmit-Cassegrain telescope, the hardest part is to looking for a guide star. ASI174 mini have 1/1.2″ big sensor which means you can have 4 times bigger Fov than 120mm.
The back of ASI mini camera is like a smiling face, it’s mouth is Type C USB port, which is widely used in mobile phones. And it’s nose is ST4 port, for guiding. Every time, you use mini camera, there will always a smile face stay with you in the dark nights.
ASI mini camera and eyepiece can reach focus at same position. You can focus with an eyepiece, and put ASI mini camera into 1.25″ holder.
Works on OAG
Mini camera is very suitable for OAG, it can have much biger focus range than normal ASI cameras. Never to worry about guide camera can not focus with main camera at same time.
Wish you all have clear skies!