SharpCap Forums

Hi Carlo,

Very nice photo. Is this your scope?
https://astromart.com/auctions/astromar ... m-f12-4506

Thanks,
Brian

Thanks, Robin. What's also amazing is that I am not using Periodic Error Correction (PEC). I am relying on PHD2 to "guide out" 60 arcsec p-p of PE. I am fortunate to have a rather large pixel scale of 2.3 arcsec per pixel. My camera's 4.65um pixels are a bit large for 418mm focal length. I...

Hi Robin, I am now able to achieve round stars using 600-second exposures. The 98% Moon was only 60 degrees away, so I used an Ha filter on a random star field, east of the meridian, +36 declination, about 45 degrees altitude. For polar alignment, I made sure that the USB cable was tied to the main ...

Perfect! I have some clear skies tonight.

Sometimes I do check PA, but I begin at the initial position again. Stupid me!

I have noticed that DEC drift subsides the closer I get to the meridian, and RA error increases.

Brian

Very nice, Dave!

Tycho is my favorite. Whenever I see an image, I compare it to these:
https://apod.nasa.gov/apod/ap130104.html
http://lroc.sese.asu.edu/posts/384

I keep looking for that boulder the size of a football field!

Brian

Robin, I should be able to solve it with Spherical Trigonometry, but I'm suffering from brain freeze this morning. I made this crude drawing: Unitron PA error.jpg This is what I think is happening. When performing PA, SharpCap is aligning my polar axis within several arc-seconds of the North Celesti...

Tim,

Yuck. There is firmware in the Mount and the Guide Camera. And then there is the electronics in each. Do you have another camera that you could try?

Brian

Hi Robin, What would be the impact of some flexure of the guide scope during the 90-degree rotation? Would it affect the alignment? I ask because PHD2 Guiding Assistant says that my PA is off by about 3 arc-minutes. I am not suggesting in any way that this is a problem with SC. There are many physic...

Gary,

I searched the net for "digital finder ASI290mmini" but came up empty. What is it?

Brian

Hi Tim, Referring to Figure 1, SharpCap and PHD2 run on the same laptop. SharpCap connects to the Imaging Camera via USB. PHD2 connects to the Guide Camera via USB. The Guide Camera's guide port connects to the Raspberry Pi via ST-4. PHD2 sends two types of commands to the guide camera. One command ...