Quote:The difference between the SQM and DSM values is actually large in all cases as the values are powers
Tony Flanders First and foremost observing love: naked eye. Second, binoculars. Last but not least, telescopes. And I sometimes dabble with cameras.
Meade LS8 ACF Meade 2" Diagonal Apetura 10" Tweakers Package Meade ETX-125, ETX-90 for Solar Celestron 80mm APO PST Meade SWA - 34mm,28mm,24mm,20mm Brandon 32mm, 16mm Vernonscope 40mm Erfle 2" ES 14mm,11mm,6.7mm 8.8 Nagler 13mm T6, Pan 19mm Meade 12.4 Pl,9.7mm, 15mm SP Meade 2x Shorty Barlow Powermate 2.5x WO Bino Viewer, 20mm 66* pair Denkmier 2 Super System Meade Nebula Filters Meade 9x60 Bino Vivitar S1 8x42 Bino Canon T2i, 18-55mm, 50mm 1.8, 55-250mm
Quote:On the other hand, being within 0.3 of the correct value is very useful data. It's far more accurate than people rating their skies by saying "I can see second-magnitude stars" -- which tells me nothing except that they're not looking very carefully.
Phyllis K LangAuthor of Deep-Sky Planner/SQM Reader Prohttp://knightware.biz
Quote:Before 10:00 the DSM shows darker readings and afterwards the SQM reads darker.
Quote:SQM are factory calibrated using standardised light sources. How is the DSM calibrated?
The difference between the SQM and DSM values is actually large in all cases as the values are powers
Quote:Jim, any chance of plotting the readings you get? May help to spot some trends with regards to DSM.
Quote:However, with millions of iPhone 4S and 5's around and a 'lite' version aimed at a general audience we can put a SQM in the hands of thousands of users worldwide. That generates a lot of useful data for the IDA and scientists ...
"I do not feel obliged to believe that the same God who has endowed us with sense, reason and intellect has intended us to forgo their use." - Galileo Galilei Celestron CPC1100 GPS (w/Hyperstar) Celestron CeleStar 8" SCT (w/ Advanced Astro Master DSCs) - SOLD Orion XT6 Dob (my kids' scope, my grab-n-go and my outreach scope) - SOLD
Quote:Consider that the SQM costs $120 and the app costs $5, I'd say it's a pretty good deal. However, it would be extremely helpful to know its limitations.