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Recommended Canon lenses for use with a CCD?


wuthton

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Could anyone recommend a Canon EF fit prime lens in the 50mm (preferred)  to 100mm (will do)  range that will manually focus without a Canon body? Also I'd like to avoid needing a lay down in a darkened room after I've paid for it. 

I have a body to stop down the aperture but my 50mm will not focus once disconnected. 

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You know that the pixel scale scale with big CCD pixels and 50mm FL really isn't going to be that nice? I used a Samyang 85 lens in Geoptik adapter with Atik 4000 cameras and, for a mosaic, it was OK because the final mosaic could be presented with each individual panel being shown at a fraction of full size. I think I only did one picture with it, a six panel Orion.

Olly

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10 hours ago, ollypenrice said:

You know that the pixel scale scale with big CCD pixels and 50mm FL really isn't going to be that nice? I used a Samyang 85 lens in Geoptik adapter with Atik 4000 cameras and, for a mosaic, it was OK because the final mosaic could be presented with each individual panel being shown at a fraction of full size. I think I only did one picture with it, a six panel Orion.

Olly

It's somewhat of a trial at the moment, I've just treated myself to a G2-8300 and I was hoping to put my Atik 314L to service with a bit of piggyback widefield, it needs to be pretty wide as the main scope is dithering. I don't want to sell the Atik as I seem to regularly suffer from sellers remorse about a week later. I've taken some test shots with a borrowed 24mm which showed promise apart from some shocking reflections around the brighter stars which I believe would have been cured by stopping down.

I haven't quite got my head around the effect of the pixel scale being out off the ballpark other than maybe square stars and a loss of detail, would drizzle help or hinder do you think? It's going to be narrowband only, 10-20min subs.

I'm thinking of getting a Canon 50mm FD, with manual aperture and at £25 it's not the end of the world if it's a failure as I have all the other bits already. I am open to statements such as "What are you doing? It's a complete waste of time" or certainly "You'd be better off with THIS lens/focal length"

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Drizzle is intended precisely to diminish the consequences of undersampling so it might work well for you. The 'look' I found using 7.2 micron pixels and 85mm FL was 'blocky' or grainy and coarse. It looked fine if shown at a very small percentage of full size, which is why it was good for mosaics, and narrowband looked considerably better tha BB because of the smaller stars. I never tried stopping the Samyang 85 down with an aperture mask but I found it worked brilliantly on a Canon 200L. Might be worth a try. It's easy to make them.

APERTURE%20MASK-M.jpg

Olly

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21 minutes ago, ollypenrice said:

Drizzle is intended precisely to diminish the consequences of undersampling so it might work well for you. The 'look' I found using 7.2 micron pixels and 85mm FL was 'blocky' or grainy and coarse. It looked fine if shown at a very small percentage of full size, which is why it was good for mosaics, and narrowband looked considerably better tha BB because of the smaller stars. I never tried stopping the Samyang 85 down with an aperture mask but I found it worked brilliantly on a Canon 200L. Might be worth a try. It's easy to make them.

APERTURE%20MASK-M.jpg

Olly

Thanks for that, bottom line is suck it and see :binkybaby:.

I'll have a go with your aperture mask trick as the 5 element diaphragm is most likely not going to be pretty.

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