Exposures for Transform coefficients

Technology VPhot
1

I asked the question of what exposures to use when imaging standard fields for transform coefficients a while ago with no response.
So last week I tried different exposures and would value comments and feedback. In order they were 60s, 30s, 10s and mean in yellow. Errors seem higher than last time I did this.
Thanks

NGC7790 BV TG results with average
NGC7790 BV TG results with average784×714 79.7 KB

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Kevin:

It obviously depends on the size of your scope and sensitivity of your camera. You want as many unsaturated comps as possible in the field (~100 with SNR >20(?), is reasonable). It is a bit of trial and error. Just use the 60 sec exposures and run the imaging/analysis over several nights. Often the B filter needs 2x longer exposures than V filter. Compare those results. They will be fine! There is nothing wrong with your errors.

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Thanks Ken, I’ll do that.