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Message: <blockquote data-quote="Binastro" data-source="post: 3420470" data-attributes="member: 111403">I have observed delicate noctilucent clouds since the  late 1960s, and try to continue to spot them in summer.They are in the north and my horizon is roofs at 6 to 8 degree elevation.I need to observe from this horizon upwards, and the NLCs appear to drift with time depending on the solar angle.Normally they are seen with the Sun 6 to 16 degrees below the horizon. They are 82km high and can be hundreds of kms away, possibly over Scotland from southern England. Binoculars can show exquisite detail. They change form slowly with time.They are dependent on the 11 year solar cycle and are also thought to be changing with climate change.Unfortunately there is a street light just below these north facing roofs. The street light has a rear shield but the side light causes ghosting.Some NLCs are only spotted with binoculars. They can be faint, elusive and the observations are difficult.Contrails and cirrus can mimic them from towns.I have had to abandon using the 1987 HR/5 for this work, which has scientific value. I cannot be hampered by poor binoculars. The HR/5 is very good mostly, but in this context 5 out of 10. Inadequate and not usable.  8.26 deg field.8x30 EII, c.2005. I thought would work but marginal 6.5/10. 8.85 degrees.10x35 EII, 2006, also marginal 6.5/10. 7.0 degrees.10x30 Canon IS II 7.0/10 usable but I need better. 2016. 6.0 degrees, rather small field.However the Conquest 10x42 HD is superb. 8.5/10. Very little ghosting. 6.65 degrees.I don't know how the top Swaro/Zeiss/Leica would perform. I suspect the Leica would do well.I understand that these observations are very specialised.All the binoculars tested are very good in their own way, but only the Conquest 10x42 HD is up to the job so far. All the binoculars are as new or close to as new.I would prefer an 8 deg plus field, but have to make do with 6.65 degrees. Perhaps the Conquest 8x32 HD would work well for the NLCs.The four Porroprism binoculars are inadequate in this context.</blockquote>

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