Dew on primary mirror of Mak-Newt (Skywatcher 190MN) or something else? Sky-Watcher Starlux 190MN / BK 190MN DS · Craig Dixon · ... · 3 · 103 · 2

3.01 Craig Dixon ... · view views · Share link
Attached is a screenshot of a 3 hour stack of 15 second subs (This is UV/IR data for the stars only to complete a project). Could this be dew on the primary mirror: I've also noticed that if I zoom in, the noise pattern is shockingly blotchy. This is a 1:1 view: Of could this be an issue with a process within WBPP? Edited ... Like

9.89 andrea tasselli ... · view views · Share link
There is no dew on primary in Maks, it just doesn't happen (well, unless you are at 100% saturation). And even if it were (which is exceedingly unlikely) it would show as a general dimming of the image, that's all. Dew on corrector would be far more easily occuring though. The grainy look is just due to the short subs you're using, which means loads of RON to deal with. Like

3.01 Craig Dixon Topic starter ... · view views · Share link
The morning after I shot this data, I looked down the tube and there was condensation in the middle of the primary mirror. I can't say for sure whether this formed during the night whilst data was being collected or in the morning but it was definitely there. Do you think this data is useable just for the stars? Like

9.89 andrea tasselli ... · view views · Share link
I guess you reached 100% humidity late in the night and given the very muggy day of yesterday that won't surprise me one bit. Chin up as at least you got clear skies while I get only clouds. Yes, the data is perfectly useable. Like

Register or login to create to post a reply.

Please note: The following tables are updated every 24 hours.

Distribution of astrophotographers

This table shows the number of distinct astrophotographers who have been assigned and IOTD/TP award compared to the total number of images awarded.
	Distinct awarded users	Total awarded images
Image of the day
Top picks
Top pick nominations

Distribution of subject types

This table shows the distribution of awards per subject type, compared to the popularity of images of that subject type.
	Image of the day	Top pick	Top pick nominations	Total submitted
Deep sky
Solar system
Extremely wide field
Star trails
Northern lights
Noctilucent clouds
Landscape
Artificial satellite

Distribution of data sources

This table shows the distribution of awards per data source, compared to the popularity of images acquired from that data source.
	Image of the day	Top pick	Top pick nominations	Total submitted
Backyard
Traveller
Own remote observatory
Amateur hosting facility
Public amaeteur data
Professional, scientific grade data
Mix of multiple sources
Other
Unknown