Funny Flats

[valleyman]

Just bought a 600D and hung it off the Telescope for the first time today to have a go at taking some FLATS. 

End result was not all that good.

Had a white T shirt over the front pulled right and pointed it up to the sky.

Had the Historgram showing a white area in the centre of the run as advised.

ISO was 400, shutter was 1/4000th. shooting RAW.

My gut tells me its a Camera problem, any advice before I start a return to MPB

You can see the dark band along the bottom of the Frame.

Then took a picture of the hills without White T shirt 

 

First Frame is using LV and 2nd is using the viewfinder

Edited September 20, 2020 by valleyman

[Davey-T]

Did you cover the viewfinder to take flats ?

Dave

[wimvb]

Before you put a t-shirt over the scope, make sure it points at the sky only, for example zenith. No trees in the foreground. You want a very even illumination to start with.

[valleyman]

2 tips received, thanks. Will have to get the ladder out if the scope is pointing at the sky before putting the T shirt on it 🤣

[Whirlwind]

1 hour ago, wimvb said:

Before you put a t-shirt over the scope, make sure it points at the sky only, for example zenith. No trees in the foreground. You want a very even illumination to start with.

Strictly speaking you want the telescope to point to the opposite side of the sun at about 30 -40 degrees altitude to minimise the sky gradient.  So in the evening you want to point east, and vice versa.