Problems Using 2X APO Barlow with 350D

[jcm]

I have not been happy with the image quality using a 2X barlow and the 350D. It was the distance from the barlow to the sensor. I unscrewed the lens barrel from the barlow and after careful measurement made an adapter bringing the sensor much closer. I have probably got the gap ( from the closest lens surface to the sensor) down to about 58mm. Did a quick lunar shot which does seem to be clearer , I could take a bit more off the length but think I will do a star test first.

130mm APO , F12 using 2X APO barlow

John

[Grant]

which particular barlow were you using John? Was it 2" or 1 1/4?

I've been using a 2" revelation barlow with my 350d and have been very pleased with the quality and increased scale so would be interesting to compare.

Cheers,

Grant

[beamish]

To my untrained and amateur eye John I'd say you've done well, some nice definition in the crater shadows on the limb.

Karlo

[jcm]

which particular barlow were you using John? Was it 2" or 1 1/4?

I've been using a 2" revelation barlow with my 350d and have been very pleased with the quality and increased scale so would be interesting to compare.

Cheers,

Grant

Its a 2" APO

John

[jcm]

To my untrained and amateur eye John I'd say you've done well, some nice definition in the crater shadows on the limb.

Karlo

Its probably me being "picky" . With my TeleVue focal reducer , sensor to reducer distance is critical to get a full frame images with no distortion. So I thought reducing the barlow to sensor distance to give close to 2X ( it was more than this before) might improve the image quality.

John

[Jamie]

Hi John

That image of the moon is a good one but....

You have to realise that no matter what equipment you throw at an image the full moon

will never be perfect from edge to edge.

This is not down to you or the equipment but the full moon its self & seeing conditions.

The fact that there is little or no detail on one side is due to what side the sun i hitting it from.