Quote:
Originally Posted by Paul Haese
This is similar to what I have been saying. So long as you can 3/4 fill your histogram with the magnification you are using, then you will get good results. So a 3x barlow with a good quality sensor will get the results you are trying to obtain. You will need several barlows to work with for varying conditions.
Even though mathematically what Ray has shown is correct; in practice frame rates to collect enough frames with low noise cameras is what you want. Each camera responds differently to this problem. Look for cameras with low read noise, deepish wells and good sensitivity. All the ones mentioned fill most of these requirements. To be honest I think the PGR cameras have the lowest noise of any camera and present very high frame rates. This comes at a cost though.
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Thanks Paul. I spoke with Bintel today on the phone, as the Black Diamond ED 120 I have was from them and they have never steered me wrong.
With all this great information and their advice, I have concluded that the DBK 618 with a 2.5x powermate will achieve the best focal length without serious loss of light reaching the sensor. I may or may not need an extension tube while imaging with the star-diagonal removed. My Starshoot Pro is on the end of the focus tube at full extension to reach focus so hopefully the DBK with powermate should be ok on there too. I have a 2 inch extension tube so I can experiment when the time comes. I also have a very nice 1.25", 2x Barlow, which I can also throw into the mix to experiment.
Thanks very much everyone for your wealth of knowledge and experience. It has all helped me to make an informed decision and at least allowed me to ask the right questions when it comes to finally purchasing today.
God bless ya's all!
Baz.
P.S. Hopefully in a year or two, (maybe less) I may be blessed with enough cash to get myself a nice 14" RC, so I think the DBK will really come into it's own on that. By then who knows, I may even upgrade the planetary camera too.