Focus for imaging when you use reading glasses..

[ChrisRichmond]

Hi

When it comes to imaging through a telescope what do you doabout focusing if you wear reading glasses to see things in focus close up?

The reason I ask is obviously it is easier to use the telescope without glasses on and focus using the telescope but this then means that when taking a photo the image is out of focus by what ever strength your glasses are.

So is there an easy way around the fact that its not as easy to use the telescope with glasses on.

PS I have a canon eos 300d which doesnt have live view.

Is there an easy way to do it or am I better off just getting a newer camera?

Cheers Chris

[Psychobilly]

I would shoot short exposures at high ISO and use a Bhatinov or the simpler Y mask to focus on a bright star,..

The diffraction pattern wouldn't be changed by your "prescription" ... you would need to review the images on the screen if you can runthe camera from a laptop or netbook then you could use eos_utils to control the camera (upto 30s exposure over USB on the older cams) and review the images on its screen...

A serial cable shutter release ( and USB/RS232 adaptor if the computer doesnt have a serial port) would alow you to take longer exposures in bulb mode using something like DSLRShutter to control the camera..

Peter...

[Zakalwe]

Hi

When it comes to imaging through a telescope what do you doabout focusing if you wear reading glasses to see things in focus close up?

The reason I ask is obviously it is easier to use the telescope without glasses on and focus using the telescope but this then means that when taking a photo the image is out of focus by what ever strength your glasses are.

So is there an easy way around the fact that its not as easy to use the telescope with glasses on.

PS I have a canon eos 300d which doesnt have live view.

Is there an easy way to do it or am I better off just getting a newer camera?

Cheers Chris

When you alter the focus for visual don't forget that you have an eyepiece in the optical train. When imaging, you remove the eyepiece (assuming that you are not doing afocal), and you focus the scope so the focused image falls onto the sensor in the camera.

Do as Psychbilly has suggested...use a Bhatinov or Y mask. It takes a lot of guess work out of it.

I see that you are in Morecambe (same as me). Do you go to the Lancaster and Morecambe Astro Society meetings in Torrisholme (first Wednesday of every month)? Feel free to PM me if you want more information.

[ChrisRichmond]

I would shoot short exposures at high ISO and use a Bhatinov or the simpler Y mask to focus on a bright star,.

Peter...

Thanks for Peter, I will have to get one of those looks easy to use.

I see that you are in Morecambe (same as me). Do you go to the Lancaster and Morecambe Astro Society meetings in Torrisholme (first Wednesday of every month)? Feel free to PM me if you want more information.

I havent been yet as I am only just starting up in this hobby, ive got a coronado pst for solar viewing and I am picking up an 8"celestron c8n-gt with nexstar goto mount on saturday for astronomical use.

I have two canon eos bodies so can modify one for astro and already have the t-ring stuff for prime focus and eyepiece projection.

So as a newbie I could take in any advice / tuition links or whatever as the last time I had a telescope was about 36 years ago and it was a cheapo tasco scope, and the one before that was a kaliedoscope...lol

Cheers Chris

[Gina]

I use a bright star (as bright as I can find) with Bahtinov mask on front of scope and live view with EOS Utility. Works well for me.