Tips For Dslr Focussing

[happy-kat]

Can't say I go that far when I use my tablet.

Why not see how you get on and make decisions on your use.

[Dazzyt66]

Thanks everyone for the advice (so far) on this thread. Here are a couple of images (single shots) I have done just by using live view and max mag on camera to get focus. The moon was done with my 150p and Orion with just my 50mm Yongnuo lens (a bargain at just over £30 new!). Both images have had s slight dabble in Canon pro image (mainly brightness)...

Comments welcome please.

ps on a super point my 16yo daughter looked through a telescope for the first time last night (first good night we've had when she's visited since I got my scopes). Her words on seeing the moon through my ST80 and 6mm Baader Ortho: "Wow.... OH WOW!". Priceless.... At 11pm freezing cold as well...

[SteveNickolls]

Thanks for your post Dazzyt66, I hope what ever method/equipment you use you have more success focusing.

My advice would be to adopt the KISS principle-try to minimise the amount of technology and number of cables as much as possible-if you are aligning your telescope say using a 2 star align, choose your second (bright) alignment star (that you have 'centered' first in a wide FOV eyepiece then in a narrower FOV eyepiece) such that it is close to your intended imaging object to improve slew accuracy. With the star in the centre of your FOV replace the diagonal and eyepiece with your camera and connector. Use this bright star to refocus on. A Bhatinov Mask needs no wires and can be your best friend when focusing. With the mask in place finely adjust focus until the two central lines run equidistant between the diagonal ones. You can use the camera's x5/x10 feature to bring up a bigger image to help focus as precisely as possible. If you are careful touching the focus knob this procedure need not produce too much wobble in the image. You could use an electric focuser but that's another wire plus a power lead. If your telescope has a screw to secure the focus point in position, secure it. If you mark the focus position on the focus tube with indelible pen or tape (if you have a focus tube with graduated divisions record the value), this will make future focusing much quicker. I have found this method works fine and my hands are left free to use. Some recent Canon DSLR's have a red colour theme option for the 'Live View' screen which is better than having to look at a bright screen and lose your night vision.

I would be concerned using a hand held device such as a Hudl to help focus as it is quite heavy to hold for long periods and you will need to keep the device connected to the camera by a relatively short usb cable all through the session as the telescope and mount rotates throughout the observing period. Additionally cold nights and devices relying on batteries are not friends. Do the apps have a 'night vision' option? If a device could control the camera wirelessly and have a 'night vision' mode this would be a better option but it's still another gizmo that could malfunction.

I'm not a Luddite (honest) but keeping things simple especially when working in the dark and cold can have their definite advantages.

However whatever you decide to do Dazzyt I wish you the best of luck and most importantly lots of clear, dark night skies.

Cheers,
Steve

 

[DorsetBlue]

13 hours ago, SteveNickolls said:

I would be concerned using a hand held device such as a Hudl to help focus as it is quite heavy to hold for long periods and you will need to keep the device connected to the camera by a relatively short usb cable all through the session as the telescope and mount rotates throughout the observing period.

I have a 1M USB cable and keep the Hudl on a music stand alongside my Star Adventurer, which worked fine.  Pity it was pointless with the Nikon, hohum.

[wornish]

I made my own Lords mask and it works pretty well.

The Bahtinov is even better though.