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Seeing Red
Gidday All,
this may have been seen before....
I have an EON80mm Orion and Canon 450d unmodded.
When I use this combo I get rather red backgrounds from my suburban back yard. At ISO 1600 for 45 sec's , always guaranteed.
So, I tried to resurrect an old MEADE ETX90 on my EQ6 and with the same camera. I don't see the red background, my be just a very little at ISO 1600 and 45 sec's subs. I took it upto 2 min's and the red back ground was still barely noticeable. A good option for me if i can lock it on to my rig correctly. May be to make it a spectrscope, with SA100.
The question is, What is changing the red character of the background?
Am I seeing warm air trapped in the EON80? Perhaps the glass characteristics? Or the cold mass of the ETX90 mirror?
If this change of optics rig makes for better backgrounds, then coolling a dslr seems a bit dramatic?
I'll added a few picture shortly.
regards, Alan.
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