Posts Made By: Ralph Encarnacion

Great picture! That 9.25 is a keeper.
Ralph

If you have a Gemini, you might want to put a new CMOS battery in it, or at least take it out and put it back in. Last week my Gemini refuse to turn on. I was ready to mail it back for repair, and then I decided to take the battery out and put it back in. That fixed it. It must have reset the processor or something. You might also check the gear box. I had a bad one of those too and was causing my autoguider to over correct when it was autoguiding and I was getting oblong stars. If you can wiggle the motor on the mount, you probably have a cracked gear box cover.
Ralph

Nice shot. Nice to see another 237 imager out there.
Ralph

I am not familiar with the MX5C type autoguider, but I do use an ST-4 and also an ST-237A autoguider. Each has there own advantages and disadvantages. The ST-4 is nice because it is stand alone and works really well. The disadvantage is that it is a lot harder to figure out how to learn how to use it. The way I learned how to use it was I hooked it up to my laptop, so I could see when the star was in focus. Once I learned how to use it with the laptop, I started using it stand alone. Now I use it stand alone all the time. The main thing that I don't like about it now is that it doesn't have a shutter, so the only way to take a dark frame is to cover up the front of the scope. My other autoguider is an ST-237A and my laptop. The ST-237 is a lot easier to use since you have a laptop screen to show you what the camera is doing. It is also a lot more sensitive and has a much bigger chip, so there are plenty of guide stars to choose from. It has a shutter, so it can take a dark frame all my itself. The main thing I dont like about it is that it takes longer to calibrate it, because of the long download times. The ST-4 calibrates fast because it doesn't have to download anything to the computer. The ST-237 is also a pretty nice camera to image with. I origanally bought the 237 to use as an autoguider for my Canon 10D. Then I started using it to image with, so I bought the ST4 to autoguide the 237. I first hated the ST4, but now that I know how to use it, I use it as my autoguider a lot more often than I use the 237.
Ralph

I think for an autoguider, the ST-237 will be your best bet. It is the same chip that Sbig puts in there STV and the guide chip they use on all their newer dual chip cameras. It is super sensitive. I normally do a one second exposur and there are usually plenty of stars to choose from to autoguide on. If you are patient, you can usually buy a used one with the filter wheel already in it. It makes a pretty good imager too. If you mount it on a fastar C-8, you can do unguided 30 second shots all night long at F/1.95. I have just started using it as an imager and have a few pictures that you can see here: http://www.pbase.com/panotaker/image/35082252 http://www.pbase.com/panotaker/image/33333243 http://www.pbase.com/panotaker/image/37369393 http://www.pbase.com/panotaker/image/36002081
Ralph

You need to make a parfocal eyepiece. That will make finding and focusing stars a lot easier. Set up your scope in the daytime with the webcam on it pointing at something far away. Adjust the focus until the webcam is in focus. Take out the webcam and put in an eyepiece, but don't touch the focus. Slide the eyepiece in and out of the barrel until it is in perfect focus. Now mark the barrel of the eyepiece with a sharpie or scribe a mark on it. Now you have a parfocal eyepiece. When you set up at night, put the parfocal eyepiece in the scope up to that scribe mark and focus the scope. Center the star in the scope, then take out the eyepiece and put the webcam in. Your star should be in the field of view of the webcam and pretty close to focus.
Ralph

Nice image Jose. You can see a nice tail on it.
Ralph

I have my little solar scope mounted on a Mini Giro mount. The Mini Giro is super smooth and it is easy to push around and keep the Sun centered. Attached, you will see an image I took today with that setup and a Nikon 990.
Ralph

For visual, a double stacked PST will be better than a single stacked MS 40. For photography, the SM 40 will be better because it has more focus travel than the PST. A PST will come to focus with a point and shoot digital, but not a DSLR.
Ralph

Who says the 237 is only good for a guide chip? Excellent image! I'm shooting the Running Man right now with my 237 and NP-101. Hopefully it will come out good enough to post. Do you have any more taken with the 237?
Ralph